1/* 2 * Copyright © 2014 Red Hat 3 * 4 * Permission to use, copy, modify, distribute, and sell this software and its 5 * documentation for any purpose is hereby granted without fee, provided that 6 * the above copyright notice appear in all copies and that both that copyright 7 * notice and this permission notice appear in supporting documentation, and 8 * that the name of the copyright holders not be used in advertising or 9 * publicity pertaining to distribution of the software without specific, 10 * written prior permission. The copyright holders make no representations 11 * about the suitability of this software for any purpose. It is provided "as 12 * is" without express or implied warranty. 13 * 14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO 16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR 17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, 18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER 19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 20 * OF THIS SOFTWARE. 21 */ 22 23#include <linux/kernel.h> 24#include <linux/delay.h> 25#include <linux/init.h> 26#include <linux/errno.h> 27#include <linux/sched.h> 28#include <linux/seq_file.h> 29#include <linux/i2c.h> 30#include <drm/drm_dp_mst_helper.h> 31#include <drm/drmP.h> 32 33#include <drm/drm_fixed.h> 34 35/** 36 * DOC: dp mst helper 37 * 38 * These functions contain parts of the DisplayPort 1.2a MultiStream Transport 39 * protocol. The helpers contain a topology manager and bandwidth manager. 40 * The helpers encapsulate the sending and received of sideband msgs. 41 */ 42static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr, 43 char *buf); 44static int test_calc_pbn_mode(void); 45 46static void drm_dp_put_port(struct drm_dp_mst_port *port); 47 48static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr, 49 int id, 50 struct drm_dp_payload *payload); 51 52static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr, 53 struct drm_dp_mst_port *port, 54 int offset, int size, u8 *bytes); 55 56static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr, 57 struct drm_dp_mst_branch *mstb); 58static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr, 59 struct drm_dp_mst_branch *mstb, 60 struct drm_dp_mst_port *port); 61static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr, 62 u8 *guid); 63 64static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux); 65static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux); 66static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr); 67/* sideband msg handling */ 68static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles) 69{ 70 u8 bitmask = 0x80; 71 u8 bitshift = 7; 72 u8 array_index = 0; 73 int number_of_bits = num_nibbles * 4; 74 u8 remainder = 0; 75 76 while (number_of_bits != 0) { 77 number_of_bits--; 78 remainder <<= 1; 79 remainder |= (data[array_index] & bitmask) >> bitshift; 80 bitmask >>= 1; 81 bitshift--; 82 if (bitmask == 0) { 83 bitmask = 0x80; 84 bitshift = 7; 85 array_index++; 86 } 87 if ((remainder & 0x10) == 0x10) 88 remainder ^= 0x13; 89 } 90 91 number_of_bits = 4; 92 while (number_of_bits != 0) { 93 number_of_bits--; 94 remainder <<= 1; 95 if ((remainder & 0x10) != 0) 96 remainder ^= 0x13; 97 } 98 99 return remainder; 100} 101 102static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes) 103{ 104 u8 bitmask = 0x80; 105 u8 bitshift = 7; 106 u8 array_index = 0; 107 int number_of_bits = number_of_bytes * 8; 108 u16 remainder = 0; 109 110 while (number_of_bits != 0) { 111 number_of_bits--; 112 remainder <<= 1; 113 remainder |= (data[array_index] & bitmask) >> bitshift; 114 bitmask >>= 1; 115 bitshift--; 116 if (bitmask == 0) { 117 bitmask = 0x80; 118 bitshift = 7; 119 array_index++; 120 } 121 if ((remainder & 0x100) == 0x100) 122 remainder ^= 0xd5; 123 } 124 125 number_of_bits = 8; 126 while (number_of_bits != 0) { 127 number_of_bits--; 128 remainder <<= 1; 129 if ((remainder & 0x100) != 0) 130 remainder ^= 0xd5; 131 } 132 133 return remainder & 0xff; 134} 135static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr) 136{ 137 u8 size = 3; 138 size += (hdr->lct / 2); 139 return size; 140} 141 142static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr, 143 u8 *buf, int *len) 144{ 145 int idx = 0; 146 int i; 147 u8 crc4; 148 buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf); 149 for (i = 0; i < (hdr->lct / 2); i++) 150 buf[idx++] = hdr->rad[i]; 151 buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) | 152 (hdr->msg_len & 0x3f); 153 buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4); 154 155 crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1); 156 buf[idx - 1] |= (crc4 & 0xf); 157 158 *len = idx; 159} 160 161static bool drm_dp_decode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr, 162 u8 *buf, int buflen, u8 *hdrlen) 163{ 164 u8 crc4; 165 u8 len; 166 int i; 167 u8 idx; 168 if (buf[0] == 0) 169 return false; 170 len = 3; 171 len += ((buf[0] & 0xf0) >> 4) / 2; 172 if (len > buflen) 173 return false; 174 crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1); 175 176 if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) { 177 DRM_DEBUG_KMS("crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]); 178 return false; 179 } 180 181 hdr->lct = (buf[0] & 0xf0) >> 4; 182 hdr->lcr = (buf[0] & 0xf); 183 idx = 1; 184 for (i = 0; i < (hdr->lct / 2); i++) 185 hdr->rad[i] = buf[idx++]; 186 hdr->broadcast = (buf[idx] >> 7) & 0x1; 187 hdr->path_msg = (buf[idx] >> 6) & 0x1; 188 hdr->msg_len = buf[idx] & 0x3f; 189 idx++; 190 hdr->somt = (buf[idx] >> 7) & 0x1; 191 hdr->eomt = (buf[idx] >> 6) & 0x1; 192 hdr->seqno = (buf[idx] >> 4) & 0x1; 193 idx++; 194 *hdrlen = idx; 195 return true; 196} 197 198static void drm_dp_encode_sideband_req(struct drm_dp_sideband_msg_req_body *req, 199 struct drm_dp_sideband_msg_tx *raw) 200{ 201 int idx = 0; 202 int i; 203 u8 *buf = raw->msg; 204 buf[idx++] = req->req_type & 0x7f; 205 206 switch (req->req_type) { 207 case DP_ENUM_PATH_RESOURCES: 208 buf[idx] = (req->u.port_num.port_number & 0xf) << 4; 209 idx++; 210 break; 211 case DP_ALLOCATE_PAYLOAD: 212 buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 | 213 (req->u.allocate_payload.number_sdp_streams & 0xf); 214 idx++; 215 buf[idx] = (req->u.allocate_payload.vcpi & 0x7f); 216 idx++; 217 buf[idx] = (req->u.allocate_payload.pbn >> 8); 218 idx++; 219 buf[idx] = (req->u.allocate_payload.pbn & 0xff); 220 idx++; 221 for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) { 222 buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) | 223 (req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf); 224 idx++; 225 } 226 if (req->u.allocate_payload.number_sdp_streams & 1) { 227 i = req->u.allocate_payload.number_sdp_streams - 1; 228 buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4; 229 idx++; 230 } 231 break; 232 case DP_QUERY_PAYLOAD: 233 buf[idx] = (req->u.query_payload.port_number & 0xf) << 4; 234 idx++; 235 buf[idx] = (req->u.query_payload.vcpi & 0x7f); 236 idx++; 237 break; 238 case DP_REMOTE_DPCD_READ: 239 buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4; 240 buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf; 241 idx++; 242 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8; 243 idx++; 244 buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff); 245 idx++; 246 buf[idx] = (req->u.dpcd_read.num_bytes); 247 idx++; 248 break; 249 250 case DP_REMOTE_DPCD_WRITE: 251 buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4; 252 buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf; 253 idx++; 254 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8; 255 idx++; 256 buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff); 257 idx++; 258 buf[idx] = (req->u.dpcd_write.num_bytes); 259 idx++; 260 memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes); 261 idx += req->u.dpcd_write.num_bytes; 262 break; 263 case DP_REMOTE_I2C_READ: 264 buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4; 265 buf[idx] |= (req->u.i2c_read.num_transactions & 0x3); 266 idx++; 267 for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) { 268 buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f; 269 idx++; 270 buf[idx] = req->u.i2c_read.transactions[i].num_bytes; 271 idx++; 272 memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes); 273 idx += req->u.i2c_read.transactions[i].num_bytes; 274 275 buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5; 276 buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf); 277 idx++; 278 } 279 buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f; 280 idx++; 281 buf[idx] = (req->u.i2c_read.num_bytes_read); 282 idx++; 283 break; 284 285 case DP_REMOTE_I2C_WRITE: 286 buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4; 287 idx++; 288 buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f; 289 idx++; 290 buf[idx] = (req->u.i2c_write.num_bytes); 291 idx++; 292 memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes); 293 idx += req->u.i2c_write.num_bytes; 294 break; 295 } 296 raw->cur_len = idx; 297} 298 299static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len) 300{ 301 u8 crc4; 302 crc4 = drm_dp_msg_data_crc4(msg, len); 303 msg[len] = crc4; 304} 305 306static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep, 307 struct drm_dp_sideband_msg_tx *raw) 308{ 309 int idx = 0; 310 u8 *buf = raw->msg; 311 312 buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f); 313 314 raw->cur_len = idx; 315} 316 317/* this adds a chunk of msg to the builder to get the final msg */ 318static bool drm_dp_sideband_msg_build(struct drm_dp_sideband_msg_rx *msg, 319 u8 *replybuf, u8 replybuflen, bool hdr) 320{ 321 int ret; 322 u8 crc4; 323 324 if (hdr) { 325 u8 hdrlen; 326 struct drm_dp_sideband_msg_hdr recv_hdr; 327 ret = drm_dp_decode_sideband_msg_hdr(&recv_hdr, replybuf, replybuflen, &hdrlen); 328 if (ret == false) { 329 print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replybuf, replybuflen, false); 330 return false; 331 } 332 333 /* get length contained in this portion */ 334 msg->curchunk_len = recv_hdr.msg_len; 335 msg->curchunk_hdrlen = hdrlen; 336 337 /* we have already gotten an somt - don't bother parsing */ 338 if (recv_hdr.somt && msg->have_somt) 339 return false; 340 341 if (recv_hdr.somt) { 342 memcpy(&msg->initial_hdr, &recv_hdr, sizeof(struct drm_dp_sideband_msg_hdr)); 343 msg->have_somt = true; 344 } 345 if (recv_hdr.eomt) 346 msg->have_eomt = true; 347 348 /* copy the bytes for the remainder of this header chunk */ 349 msg->curchunk_idx = min(msg->curchunk_len, (u8)(replybuflen - hdrlen)); 350 memcpy(&msg->chunk[0], replybuf + hdrlen, msg->curchunk_idx); 351 } else { 352 memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen); 353 msg->curchunk_idx += replybuflen; 354 } 355 356 if (msg->curchunk_idx >= msg->curchunk_len) { 357 /* do CRC */ 358 crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1); 359 /* copy chunk into bigger msg */ 360 memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1); 361 msg->curlen += msg->curchunk_len - 1; 362 } 363 return true; 364} 365 366static bool drm_dp_sideband_parse_link_address(struct drm_dp_sideband_msg_rx *raw, 367 struct drm_dp_sideband_msg_reply_body *repmsg) 368{ 369 int idx = 1; 370 int i; 371 memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16); 372 idx += 16; 373 repmsg->u.link_addr.nports = raw->msg[idx] & 0xf; 374 idx++; 375 if (idx > raw->curlen) 376 goto fail_len; 377 for (i = 0; i < repmsg->u.link_addr.nports; i++) { 378 if (raw->msg[idx] & 0x80) 379 repmsg->u.link_addr.ports[i].input_port = 1; 380 381 repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7; 382 repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf); 383 384 idx++; 385 if (idx > raw->curlen) 386 goto fail_len; 387 repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1; 388 repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1; 389 if (repmsg->u.link_addr.ports[i].input_port == 0) 390 repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1; 391 idx++; 392 if (idx > raw->curlen) 393 goto fail_len; 394 if (repmsg->u.link_addr.ports[i].input_port == 0) { 395 repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]); 396 idx++; 397 if (idx > raw->curlen) 398 goto fail_len; 399 memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16); 400 idx += 16; 401 if (idx > raw->curlen) 402 goto fail_len; 403 repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf; 404 repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf); 405 idx++; 406 407 } 408 if (idx > raw->curlen) 409 goto fail_len; 410 } 411 412 return true; 413fail_len: 414 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen); 415 return false; 416} 417 418static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw, 419 struct drm_dp_sideband_msg_reply_body *repmsg) 420{ 421 int idx = 1; 422 repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf; 423 idx++; 424 if (idx > raw->curlen) 425 goto fail_len; 426 repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx]; 427 if (idx > raw->curlen) 428 goto fail_len; 429 430 memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes); 431 return true; 432fail_len: 433 DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen); 434 return false; 435} 436 437static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw, 438 struct drm_dp_sideband_msg_reply_body *repmsg) 439{ 440 int idx = 1; 441 repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf; 442 idx++; 443 if (idx > raw->curlen) 444 goto fail_len; 445 return true; 446fail_len: 447 DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen); 448 return false; 449} 450 451static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw, 452 struct drm_dp_sideband_msg_reply_body *repmsg) 453{ 454 int idx = 1; 455 456 repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf); 457 idx++; 458 if (idx > raw->curlen) 459 goto fail_len; 460 repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx]; 461 idx++; 462 /* TODO check */ 463 memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes); 464 return true; 465fail_len: 466 DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen); 467 return false; 468} 469 470static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw, 471 struct drm_dp_sideband_msg_reply_body *repmsg) 472{ 473 int idx = 1; 474 repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf; 475 idx++; 476 if (idx > raw->curlen) 477 goto fail_len; 478 repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]); 479 idx += 2; 480 if (idx > raw->curlen) 481 goto fail_len; 482 repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]); 483 idx += 2; 484 if (idx > raw->curlen) 485 goto fail_len; 486 return true; 487fail_len: 488 DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen); 489 return false; 490} 491 492static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw, 493 struct drm_dp_sideband_msg_reply_body *repmsg) 494{ 495 int idx = 1; 496 repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf; 497 idx++; 498 if (idx > raw->curlen) 499 goto fail_len; 500 repmsg->u.allocate_payload.vcpi = raw->msg[idx]; 501 idx++; 502 if (idx > raw->curlen) 503 goto fail_len; 504 repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]); 505 idx += 2; 506 if (idx > raw->curlen) 507 goto fail_len; 508 return true; 509fail_len: 510 DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen); 511 return false; 512} 513 514static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw, 515 struct drm_dp_sideband_msg_reply_body *repmsg) 516{ 517 int idx = 1; 518 repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf; 519 idx++; 520 if (idx > raw->curlen) 521 goto fail_len; 522 repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]); 523 idx += 2; 524 if (idx > raw->curlen) 525 goto fail_len; 526 return true; 527fail_len: 528 DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen); 529 return false; 530} 531 532static bool drm_dp_sideband_parse_reply(struct drm_dp_sideband_msg_rx *raw, 533 struct drm_dp_sideband_msg_reply_body *msg) 534{ 535 memset(msg, 0, sizeof(*msg)); 536 msg->reply_type = (raw->msg[0] & 0x80) >> 7; 537 msg->req_type = (raw->msg[0] & 0x7f); 538 539 if (msg->reply_type) { 540 memcpy(msg->u.nak.guid, &raw->msg[1], 16); 541 msg->u.nak.reason = raw->msg[17]; 542 msg->u.nak.nak_data = raw->msg[18]; 543 return false; 544 } 545 546 switch (msg->req_type) { 547 case DP_LINK_ADDRESS: 548 return drm_dp_sideband_parse_link_address(raw, msg); 549 case DP_QUERY_PAYLOAD: 550 return drm_dp_sideband_parse_query_payload_ack(raw, msg); 551 case DP_REMOTE_DPCD_READ: 552 return drm_dp_sideband_parse_remote_dpcd_read(raw, msg); 553 case DP_REMOTE_DPCD_WRITE: 554 return drm_dp_sideband_parse_remote_dpcd_write(raw, msg); 555 case DP_REMOTE_I2C_READ: 556 return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg); 557 case DP_ENUM_PATH_RESOURCES: 558 return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg); 559 case DP_ALLOCATE_PAYLOAD: 560 return drm_dp_sideband_parse_allocate_payload_ack(raw, msg); 561 default: 562 DRM_ERROR("Got unknown reply 0x%02x\n", msg->req_type); 563 return false; 564 } 565} 566 567static bool drm_dp_sideband_parse_connection_status_notify(struct drm_dp_sideband_msg_rx *raw, 568 struct drm_dp_sideband_msg_req_body *msg) 569{ 570 int idx = 1; 571 572 msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4; 573 idx++; 574 if (idx > raw->curlen) 575 goto fail_len; 576 577 memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16); 578 idx += 16; 579 if (idx > raw->curlen) 580 goto fail_len; 581 582 msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1; 583 msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1; 584 msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1; 585 msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1; 586 msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7); 587 idx++; 588 return true; 589fail_len: 590 DRM_DEBUG_KMS("connection status reply parse length fail %d %d\n", idx, raw->curlen); 591 return false; 592} 593 594static bool drm_dp_sideband_parse_resource_status_notify(struct drm_dp_sideband_msg_rx *raw, 595 struct drm_dp_sideband_msg_req_body *msg) 596{ 597 int idx = 1; 598 599 msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4; 600 idx++; 601 if (idx > raw->curlen) 602 goto fail_len; 603 604 memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16); 605 idx += 16; 606 if (idx > raw->curlen) 607 goto fail_len; 608 609 msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]); 610 idx++; 611 return true; 612fail_len: 613 DRM_DEBUG_KMS("resource status reply parse length fail %d %d\n", idx, raw->curlen); 614 return false; 615} 616 617static bool drm_dp_sideband_parse_req(struct drm_dp_sideband_msg_rx *raw, 618 struct drm_dp_sideband_msg_req_body *msg) 619{ 620 memset(msg, 0, sizeof(*msg)); 621 msg->req_type = (raw->msg[0] & 0x7f); 622 623 switch (msg->req_type) { 624 case DP_CONNECTION_STATUS_NOTIFY: 625 return drm_dp_sideband_parse_connection_status_notify(raw, msg); 626 case DP_RESOURCE_STATUS_NOTIFY: 627 return drm_dp_sideband_parse_resource_status_notify(raw, msg); 628 default: 629 DRM_ERROR("Got unknown request 0x%02x\n", msg->req_type); 630 return false; 631 } 632} 633 634static int build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes) 635{ 636 struct drm_dp_sideband_msg_req_body req; 637 638 req.req_type = DP_REMOTE_DPCD_WRITE; 639 req.u.dpcd_write.port_number = port_num; 640 req.u.dpcd_write.dpcd_address = offset; 641 req.u.dpcd_write.num_bytes = num_bytes; 642 req.u.dpcd_write.bytes = bytes; 643 drm_dp_encode_sideband_req(&req, msg); 644 645 return 0; 646} 647 648static int build_link_address(struct drm_dp_sideband_msg_tx *msg) 649{ 650 struct drm_dp_sideband_msg_req_body req; 651 652 req.req_type = DP_LINK_ADDRESS; 653 drm_dp_encode_sideband_req(&req, msg); 654 return 0; 655} 656 657static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num) 658{ 659 struct drm_dp_sideband_msg_req_body req; 660 661 req.req_type = DP_ENUM_PATH_RESOURCES; 662 req.u.port_num.port_number = port_num; 663 drm_dp_encode_sideband_req(&req, msg); 664 msg->path_msg = true; 665 return 0; 666} 667 668static int build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num, 669 u8 vcpi, uint16_t pbn) 670{ 671 struct drm_dp_sideband_msg_req_body req; 672 memset(&req, 0, sizeof(req)); 673 req.req_type = DP_ALLOCATE_PAYLOAD; 674 req.u.allocate_payload.port_number = port_num; 675 req.u.allocate_payload.vcpi = vcpi; 676 req.u.allocate_payload.pbn = pbn; 677 drm_dp_encode_sideband_req(&req, msg); 678 msg->path_msg = true; 679 return 0; 680} 681 682static int drm_dp_mst_assign_payload_id(struct drm_dp_mst_topology_mgr *mgr, 683 struct drm_dp_vcpi *vcpi) 684{ 685 int ret, vcpi_ret; 686 687 mutex_lock(&mgr->payload_lock); 688 ret = find_first_zero_bit(&mgr->payload_mask, mgr->max_payloads + 1); 689 if (ret > mgr->max_payloads) { 690 ret = -EINVAL; 691 DRM_DEBUG_KMS("out of payload ids %d\n", ret); 692 goto out_unlock; 693 } 694 695 vcpi_ret = find_first_zero_bit(&mgr->vcpi_mask, mgr->max_payloads + 1); 696 if (vcpi_ret > mgr->max_payloads) { 697 ret = -EINVAL; 698 DRM_DEBUG_KMS("out of vcpi ids %d\n", ret); 699 goto out_unlock; 700 } 701 702 set_bit(ret, &mgr->payload_mask); 703 set_bit(vcpi_ret, &mgr->vcpi_mask); 704 vcpi->vcpi = vcpi_ret + 1; 705 mgr->proposed_vcpis[ret - 1] = vcpi; 706out_unlock: 707 mutex_unlock(&mgr->payload_lock); 708 return ret; 709} 710 711static void drm_dp_mst_put_payload_id(struct drm_dp_mst_topology_mgr *mgr, 712 int vcpi) 713{ 714 int i; 715 if (vcpi == 0) 716 return; 717 718 mutex_lock(&mgr->payload_lock); 719 DRM_DEBUG_KMS("putting payload %d\n", vcpi); 720 clear_bit(vcpi - 1, &mgr->vcpi_mask); 721 722 for (i = 0; i < mgr->max_payloads; i++) { 723 if (mgr->proposed_vcpis[i]) 724 if (mgr->proposed_vcpis[i]->vcpi == vcpi) { 725 mgr->proposed_vcpis[i] = NULL; 726 clear_bit(i + 1, &mgr->payload_mask); 727 } 728 } 729 mutex_unlock(&mgr->payload_lock); 730} 731 732static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr, 733 struct drm_dp_sideband_msg_tx *txmsg) 734{ 735 bool ret; 736 737 /* 738 * All updates to txmsg->state are protected by mgr->qlock, and the two 739 * cases we check here are terminal states. For those the barriers 740 * provided by the wake_up/wait_event pair are enough. 741 */ 742 ret = (txmsg->state == DRM_DP_SIDEBAND_TX_RX || 743 txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT); 744 return ret; 745} 746 747static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb, 748 struct drm_dp_sideband_msg_tx *txmsg) 749{ 750 struct drm_dp_mst_topology_mgr *mgr = mstb->mgr; 751 int ret; 752 753 ret = wait_event_timeout(mgr->tx_waitq, 754 check_txmsg_state(mgr, txmsg), 755 (4 * HZ)); 756 mutex_lock(&mstb->mgr->qlock); 757 if (ret > 0) { 758 if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) { 759 ret = -EIO; 760 goto out; 761 } 762 } else { 763 DRM_DEBUG_KMS("timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno); 764 765 /* dump some state */ 766 ret = -EIO; 767 768 /* remove from q */ 769 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED || 770 txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) { 771 list_del(&txmsg->next); 772 } 773 774 if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND || 775 txmsg->state == DRM_DP_SIDEBAND_TX_SENT) { 776 mstb->tx_slots[txmsg->seqno] = NULL; 777 } 778 } 779out: 780 mutex_unlock(&mgr->qlock); 781 782 return ret; 783} 784 785static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad) 786{ 787 struct drm_dp_mst_branch *mstb; 788 789 mstb = kzalloc(sizeof(*mstb), GFP_KERNEL); 790 if (!mstb) 791 return NULL; 792 793 mstb->lct = lct; 794 if (lct > 1) 795 memcpy(mstb->rad, rad, lct / 2); 796 INIT_LIST_HEAD(&mstb->ports); 797 kref_init(&mstb->kref); 798 return mstb; 799} 800 801static void drm_dp_free_mst_port(struct kref *kref); 802 803static void drm_dp_free_mst_branch_device(struct kref *kref) 804{ 805 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref); 806 if (mstb->port_parent) { 807 if (list_empty(&mstb->port_parent->next)) 808 kref_put(&mstb->port_parent->kref, drm_dp_free_mst_port); 809 } 810 kfree(mstb); 811} 812 813static void drm_dp_destroy_mst_branch_device(struct kref *kref) 814{ 815 struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref); 816 struct drm_dp_mst_port *port, *tmp; 817 bool wake_tx = false; 818 819 /* 820 * init kref again to be used by ports to remove mst branch when it is 821 * not needed anymore 822 */ 823 kref_init(kref); 824 825 if (mstb->port_parent && list_empty(&mstb->port_parent->next)) 826 kref_get(&mstb->port_parent->kref); 827 828 /* 829 * destroy all ports - don't need lock 830 * as there are no more references to the mst branch 831 * device at this point. 832 */ 833 list_for_each_entry_safe(port, tmp, &mstb->ports, next) { 834 list_del(&port->next); 835 drm_dp_put_port(port); 836 } 837 838 /* drop any tx slots msg */ 839 mutex_lock(&mstb->mgr->qlock); 840 if (mstb->tx_slots[0]) { 841 mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT; 842 mstb->tx_slots[0] = NULL; 843 wake_tx = true; 844 } 845 if (mstb->tx_slots[1]) { 846 mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT; 847 mstb->tx_slots[1] = NULL; 848 wake_tx = true; 849 } 850 mutex_unlock(&mstb->mgr->qlock); 851 852 if (wake_tx) 853 wake_up(&mstb->mgr->tx_waitq); 854 855 kref_put(kref, drm_dp_free_mst_branch_device); 856} 857 858static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb) 859{ 860 kref_put(&mstb->kref, drm_dp_destroy_mst_branch_device); 861} 862 863 864static void drm_dp_port_teardown_pdt(struct drm_dp_mst_port *port, int old_pdt) 865{ 866 struct drm_dp_mst_branch *mstb; 867 868 switch (old_pdt) { 869 case DP_PEER_DEVICE_DP_LEGACY_CONV: 870 case DP_PEER_DEVICE_SST_SINK: 871 /* remove i2c over sideband */ 872 drm_dp_mst_unregister_i2c_bus(&port->aux); 873 break; 874 case DP_PEER_DEVICE_MST_BRANCHING: 875 mstb = port->mstb; 876 port->mstb = NULL; 877 drm_dp_put_mst_branch_device(mstb); 878 break; 879 } 880} 881 882static void drm_dp_destroy_port(struct kref *kref) 883{ 884 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref); 885 struct drm_dp_mst_topology_mgr *mgr = port->mgr; 886 887 if (!port->input) { 888 port->vcpi.num_slots = 0; 889 890 kfree(port->cached_edid); 891 892 /* 893 * The only time we don't have a connector 894 * on an output port is if the connector init 895 * fails. 896 */ 897 if (port->connector) { 898 /* we can't destroy the connector here, as 899 * we might be holding the mode_config.mutex 900 * from an EDID retrieval */ 901 902 mutex_lock(&mgr->destroy_connector_lock); 903 kref_get(&port->parent->kref); 904 list_add(&port->next, &mgr->destroy_connector_list); 905 mutex_unlock(&mgr->destroy_connector_lock); 906 schedule_work(&mgr->destroy_connector_work); 907 return; 908 } 909 /* no need to clean up vcpi 910 * as if we have no connector we never setup a vcpi */ 911 drm_dp_port_teardown_pdt(port, port->pdt); 912 } 913 kfree(port); 914} 915 916static void drm_dp_put_port(struct drm_dp_mst_port *port) 917{ 918 kref_put(&port->kref, drm_dp_destroy_port); 919} 920 921static struct drm_dp_mst_branch *drm_dp_mst_get_validated_mstb_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_branch *to_find) 922{ 923 struct drm_dp_mst_port *port; 924 struct drm_dp_mst_branch *rmstb; 925 if (to_find == mstb) { 926 kref_get(&mstb->kref); 927 return mstb; 928 } 929 list_for_each_entry(port, &mstb->ports, next) { 930 if (port->mstb) { 931 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(port->mstb, to_find); 932 if (rmstb) 933 return rmstb; 934 } 935 } 936 return NULL; 937} 938 939static struct drm_dp_mst_branch *drm_dp_get_validated_mstb_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb) 940{ 941 struct drm_dp_mst_branch *rmstb = NULL; 942 mutex_lock(&mgr->lock); 943 if (mgr->mst_primary) 944 rmstb = drm_dp_mst_get_validated_mstb_ref_locked(mgr->mst_primary, mstb); 945 mutex_unlock(&mgr->lock); 946 return rmstb; 947} 948 949static struct drm_dp_mst_port *drm_dp_mst_get_port_ref_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *to_find) 950{ 951 struct drm_dp_mst_port *port, *mport; 952 953 list_for_each_entry(port, &mstb->ports, next) { 954 if (port == to_find) { 955 kref_get(&port->kref); 956 return port; 957 } 958 if (port->mstb) { 959 mport = drm_dp_mst_get_port_ref_locked(port->mstb, to_find); 960 if (mport) 961 return mport; 962 } 963 } 964 return NULL; 965} 966 967static struct drm_dp_mst_port *drm_dp_get_validated_port_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 968{ 969 struct drm_dp_mst_port *rport = NULL; 970 mutex_lock(&mgr->lock); 971 if (mgr->mst_primary) 972 rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port); 973 mutex_unlock(&mgr->lock); 974 return rport; 975} 976 977static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num) 978{ 979 struct drm_dp_mst_port *port; 980 981 list_for_each_entry(port, &mstb->ports, next) { 982 if (port->port_num == port_num) { 983 kref_get(&port->kref); 984 return port; 985 } 986 } 987 988 return NULL; 989} 990 991/* 992 * calculate a new RAD for this MST branch device 993 * if parent has an LCT of 2 then it has 1 nibble of RAD, 994 * if parent has an LCT of 3 then it has 2 nibbles of RAD, 995 */ 996static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port, 997 u8 *rad) 998{ 999 int parent_lct = port->parent->lct; 1000 int shift = 4; 1001 int idx = (parent_lct - 1) / 2; 1002 if (parent_lct > 1) { 1003 memcpy(rad, port->parent->rad, idx + 1); 1004 shift = (parent_lct % 2) ? 4 : 0; 1005 } else 1006 rad[0] = 0; 1007 1008 rad[idx] |= port->port_num << shift; 1009 return parent_lct + 1; 1010} 1011 1012/* 1013 * return sends link address for new mstb 1014 */ 1015static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port) 1016{ 1017 int ret; 1018 u8 rad[6], lct; 1019 bool send_link = false; 1020 switch (port->pdt) { 1021 case DP_PEER_DEVICE_DP_LEGACY_CONV: 1022 case DP_PEER_DEVICE_SST_SINK: 1023 /* add i2c over sideband */ 1024 ret = drm_dp_mst_register_i2c_bus(&port->aux); 1025 break; 1026 case DP_PEER_DEVICE_MST_BRANCHING: 1027 lct = drm_dp_calculate_rad(port, rad); 1028 1029 port->mstb = drm_dp_add_mst_branch_device(lct, rad); 1030 port->mstb->mgr = port->mgr; 1031 port->mstb->port_parent = port; 1032 1033 send_link = true; 1034 break; 1035 } 1036 return send_link; 1037} 1038 1039static void drm_dp_check_mstb_guid(struct drm_dp_mst_branch *mstb, u8 *guid) 1040{ 1041 int ret; 1042 1043 memcpy(mstb->guid, guid, 16); 1044 1045 if (!drm_dp_validate_guid(mstb->mgr, mstb->guid)) { 1046 if (mstb->port_parent) { 1047 ret = drm_dp_send_dpcd_write( 1048 mstb->mgr, 1049 mstb->port_parent, 1050 DP_GUID, 1051 16, 1052 mstb->guid); 1053 } else { 1054 1055 ret = drm_dp_dpcd_write( 1056 mstb->mgr->aux, 1057 DP_GUID, 1058 mstb->guid, 1059 16); 1060 } 1061 } 1062} 1063 1064static void build_mst_prop_path(struct drm_dp_mst_port *port, 1065 struct drm_dp_mst_branch *mstb, 1066 char *proppath, 1067 size_t proppath_size) 1068{ 1069 int i; 1070 char temp[8]; 1071 snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id); 1072 for (i = 0; i < (mstb->lct - 1); i++) { 1073 int shift = (i % 2) ? 0 : 4; 1074 int port_num = (mstb->rad[i / 2] >> shift) & 0xf; 1075 snprintf(temp, sizeof(temp), "-%d", port_num); 1076 strlcat(proppath, temp, proppath_size); 1077 } 1078 snprintf(temp, sizeof(temp), "-%d", port->port_num); 1079 strlcat(proppath, temp, proppath_size); 1080} 1081 1082static void drm_dp_add_port(struct drm_dp_mst_branch *mstb, 1083 struct device *dev, 1084 struct drm_dp_link_addr_reply_port *port_msg) 1085{ 1086 struct drm_dp_mst_port *port; 1087 bool ret; 1088 bool created = false; 1089 int old_pdt = 0; 1090 int old_ddps = 0; 1091 port = drm_dp_get_port(mstb, port_msg->port_number); 1092 if (!port) { 1093 port = kzalloc(sizeof(*port), GFP_KERNEL); 1094 if (!port) 1095 return; 1096 kref_init(&port->kref); 1097 port->parent = mstb; 1098 port->port_num = port_msg->port_number; 1099 port->mgr = mstb->mgr; 1100 port->aux.name = "DPMST"; 1101 port->aux.dev = dev; 1102 created = true; 1103 } else { 1104 old_pdt = port->pdt; 1105 old_ddps = port->ddps; 1106 } 1107 1108 port->pdt = port_msg->peer_device_type; 1109 port->input = port_msg->input_port; 1110 port->mcs = port_msg->mcs; 1111 port->ddps = port_msg->ddps; 1112 port->ldps = port_msg->legacy_device_plug_status; 1113 port->dpcd_rev = port_msg->dpcd_revision; 1114 port->num_sdp_streams = port_msg->num_sdp_streams; 1115 port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks; 1116 1117 /* manage mstb port lists with mgr lock - take a reference 1118 for this list */ 1119 if (created) { 1120 mutex_lock(&mstb->mgr->lock); 1121 kref_get(&port->kref); 1122 list_add(&port->next, &mstb->ports); 1123 mutex_unlock(&mstb->mgr->lock); 1124 } 1125 1126 if (old_ddps != port->ddps) { 1127 if (port->ddps) { 1128 if (!port->input) 1129 drm_dp_send_enum_path_resources(mstb->mgr, mstb, port); 1130 } else { 1131 port->available_pbn = 0; 1132 } 1133 } 1134 1135 if (old_pdt != port->pdt && !port->input) { 1136 drm_dp_port_teardown_pdt(port, old_pdt); 1137 1138 ret = drm_dp_port_setup_pdt(port); 1139 if (ret == true) { 1140 drm_dp_send_link_address(mstb->mgr, port->mstb); 1141 port->mstb->link_address_sent = true; 1142 } 1143 } 1144 1145 if (created && !port->input) { 1146 char proppath[255]; 1147 build_mst_prop_path(port, mstb, proppath, sizeof(proppath)); 1148 port->connector = (*mstb->mgr->cbs->add_connector)(mstb->mgr, port, proppath); 1149 if (!port->connector) { 1150 /* remove it from the port list */ 1151 mutex_lock(&mstb->mgr->lock); 1152 list_del(&port->next); 1153 mutex_unlock(&mstb->mgr->lock); 1154 /* drop port list reference */ 1155 drm_dp_put_port(port); 1156 goto out; 1157 } 1158 if (port->port_num >= 8) { 1159 port->cached_edid = drm_get_edid(port->connector, &port->aux.ddc); 1160 } 1161 } 1162 1163out: 1164 /* put reference to this port */ 1165 drm_dp_put_port(port); 1166} 1167 1168static void drm_dp_update_port(struct drm_dp_mst_branch *mstb, 1169 struct drm_dp_connection_status_notify *conn_stat) 1170{ 1171 struct drm_dp_mst_port *port; 1172 int old_pdt; 1173 int old_ddps; 1174 bool dowork = false; 1175 port = drm_dp_get_port(mstb, conn_stat->port_number); 1176 if (!port) 1177 return; 1178 1179 old_ddps = port->ddps; 1180 old_pdt = port->pdt; 1181 port->pdt = conn_stat->peer_device_type; 1182 port->mcs = conn_stat->message_capability_status; 1183 port->ldps = conn_stat->legacy_device_plug_status; 1184 port->ddps = conn_stat->displayport_device_plug_status; 1185 1186 if (old_ddps != port->ddps) { 1187 if (port->ddps) { 1188 dowork = true; 1189 } else { 1190 port->available_pbn = 0; 1191 } 1192 } 1193 if (old_pdt != port->pdt && !port->input) { 1194 drm_dp_port_teardown_pdt(port, old_pdt); 1195 1196 if (drm_dp_port_setup_pdt(port)) 1197 dowork = true; 1198 } 1199 1200 drm_dp_put_port(port); 1201 if (dowork) 1202 queue_work(system_long_wq, &mstb->mgr->work); 1203 1204} 1205 1206static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr, 1207 u8 lct, u8 *rad) 1208{ 1209 struct drm_dp_mst_branch *mstb; 1210 struct drm_dp_mst_port *port; 1211 int i; 1212 /* find the port by iterating down */ 1213 1214 mutex_lock(&mgr->lock); 1215 mstb = mgr->mst_primary; 1216 1217 for (i = 0; i < lct - 1; i++) { 1218 int shift = (i % 2) ? 0 : 4; 1219 int port_num = (rad[i / 2] >> shift) & 0xf; 1220 1221 list_for_each_entry(port, &mstb->ports, next) { 1222 if (port->port_num == port_num) { 1223 mstb = port->mstb; 1224 if (!mstb) { 1225 DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]); 1226 goto out; 1227 } 1228 1229 break; 1230 } 1231 } 1232 } 1233 kref_get(&mstb->kref); 1234out: 1235 mutex_unlock(&mgr->lock); 1236 return mstb; 1237} 1238 1239static struct drm_dp_mst_branch *get_mst_branch_device_by_guid_helper( 1240 struct drm_dp_mst_branch *mstb, 1241 uint8_t *guid) 1242{ 1243 struct drm_dp_mst_branch *found_mstb; 1244 struct drm_dp_mst_port *port; 1245 1246 if (memcmp(mstb->guid, guid, 16) == 0) 1247 return mstb; 1248 1249 1250 list_for_each_entry(port, &mstb->ports, next) { 1251 if (!port->mstb) 1252 continue; 1253 1254 found_mstb = get_mst_branch_device_by_guid_helper(port->mstb, guid); 1255 1256 if (found_mstb) 1257 return found_mstb; 1258 } 1259 1260 return NULL; 1261} 1262 1263static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device_by_guid( 1264 struct drm_dp_mst_topology_mgr *mgr, 1265 uint8_t *guid) 1266{ 1267 struct drm_dp_mst_branch *mstb; 1268 1269 /* find the port by iterating down */ 1270 mutex_lock(&mgr->lock); 1271 1272 mstb = get_mst_branch_device_by_guid_helper(mgr->mst_primary, guid); 1273 1274 if (mstb) 1275 kref_get(&mstb->kref); 1276 1277 mutex_unlock(&mgr->lock); 1278 return mstb; 1279} 1280 1281static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr, 1282 struct drm_dp_mst_branch *mstb) 1283{ 1284 struct drm_dp_mst_port *port; 1285 struct drm_dp_mst_branch *mstb_child; 1286 if (!mstb->link_address_sent) { 1287 drm_dp_send_link_address(mgr, mstb); 1288 mstb->link_address_sent = true; 1289 } 1290 list_for_each_entry(port, &mstb->ports, next) { 1291 if (port->input) 1292 continue; 1293 1294 if (!port->ddps) 1295 continue; 1296 1297 if (!port->available_pbn) 1298 drm_dp_send_enum_path_resources(mgr, mstb, port); 1299 1300 if (port->mstb) { 1301 mstb_child = drm_dp_get_validated_mstb_ref(mgr, port->mstb); 1302 if (mstb_child) { 1303 drm_dp_check_and_send_link_address(mgr, mstb_child); 1304 drm_dp_put_mst_branch_device(mstb_child); 1305 } 1306 } 1307 } 1308} 1309 1310static void drm_dp_mst_link_probe_work(struct work_struct *work) 1311{ 1312 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work); 1313 struct drm_dp_mst_branch *mstb; 1314 1315 mutex_lock(&mgr->lock); 1316 mstb = mgr->mst_primary; 1317 if (mstb) { 1318 kref_get(&mstb->kref); 1319 } 1320 mutex_unlock(&mgr->lock); 1321 if (mstb) { 1322 drm_dp_check_and_send_link_address(mgr, mstb); 1323 drm_dp_put_mst_branch_device(mstb); 1324 } 1325} 1326 1327static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr, 1328 u8 *guid) 1329{ 1330 static u8 zero_guid[16]; 1331 1332 if (!memcmp(guid, zero_guid, 16)) { 1333 u64 salt = get_jiffies_64(); 1334 memcpy(&guid[0], &salt, sizeof(u64)); 1335 memcpy(&guid[8], &salt, sizeof(u64)); 1336 return false; 1337 } 1338 return true; 1339} 1340 1341#if 0 1342static int build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes) 1343{ 1344 struct drm_dp_sideband_msg_req_body req; 1345 1346 req.req_type = DP_REMOTE_DPCD_READ; 1347 req.u.dpcd_read.port_number = port_num; 1348 req.u.dpcd_read.dpcd_address = offset; 1349 req.u.dpcd_read.num_bytes = num_bytes; 1350 drm_dp_encode_sideband_req(&req, msg); 1351 1352 return 0; 1353} 1354#endif 1355 1356static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr, 1357 bool up, u8 *msg, int len) 1358{ 1359 int ret; 1360 int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE; 1361 int tosend, total, offset; 1362 int retries = 0; 1363 1364retry: 1365 total = len; 1366 offset = 0; 1367 do { 1368 tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total); 1369 1370 ret = drm_dp_dpcd_write(mgr->aux, regbase + offset, 1371 &msg[offset], 1372 tosend); 1373 if (ret != tosend) { 1374 if (ret == -EIO && retries < 5) { 1375 retries++; 1376 goto retry; 1377 } 1378 DRM_DEBUG_KMS("failed to dpcd write %d %d\n", tosend, ret); 1379 1380 return -EIO; 1381 } 1382 offset += tosend; 1383 total -= tosend; 1384 } while (total > 0); 1385 return 0; 1386} 1387 1388static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr, 1389 struct drm_dp_sideband_msg_tx *txmsg) 1390{ 1391 struct drm_dp_mst_branch *mstb = txmsg->dst; 1392 u8 req_type; 1393 1394 /* both msg slots are full */ 1395 if (txmsg->seqno == -1) { 1396 if (mstb->tx_slots[0] && mstb->tx_slots[1]) { 1397 DRM_DEBUG_KMS("%s: failed to find slot\n", __func__); 1398 return -EAGAIN; 1399 } 1400 if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) { 1401 txmsg->seqno = mstb->last_seqno; 1402 mstb->last_seqno ^= 1; 1403 } else if (mstb->tx_slots[0] == NULL) 1404 txmsg->seqno = 0; 1405 else 1406 txmsg->seqno = 1; 1407 mstb->tx_slots[txmsg->seqno] = txmsg; 1408 } 1409 1410 req_type = txmsg->msg[0] & 0x7f; 1411 if (req_type == DP_CONNECTION_STATUS_NOTIFY || 1412 req_type == DP_RESOURCE_STATUS_NOTIFY) 1413 hdr->broadcast = 1; 1414 else 1415 hdr->broadcast = 0; 1416 hdr->path_msg = txmsg->path_msg; 1417 hdr->lct = mstb->lct; 1418 hdr->lcr = mstb->lct - 1; 1419 if (mstb->lct > 1) 1420 memcpy(hdr->rad, mstb->rad, mstb->lct / 2); 1421 hdr->seqno = txmsg->seqno; 1422 return 0; 1423} 1424/* 1425 * process a single block of the next message in the sideband queue 1426 */ 1427static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr, 1428 struct drm_dp_sideband_msg_tx *txmsg, 1429 bool up) 1430{ 1431 u8 chunk[48]; 1432 struct drm_dp_sideband_msg_hdr hdr; 1433 int len, space, idx, tosend; 1434 int ret; 1435 1436 memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr)); 1437 1438 if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) { 1439 txmsg->seqno = -1; 1440 txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND; 1441 } 1442 1443 /* make hdr from dst mst - for replies use seqno 1444 otherwise assign one */ 1445 ret = set_hdr_from_dst_qlock(&hdr, txmsg); 1446 if (ret < 0) 1447 return ret; 1448 1449 /* amount left to send in this message */ 1450 len = txmsg->cur_len - txmsg->cur_offset; 1451 1452 /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */ 1453 space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr); 1454 1455 tosend = min(len, space); 1456 if (len == txmsg->cur_len) 1457 hdr.somt = 1; 1458 if (space >= len) 1459 hdr.eomt = 1; 1460 1461 1462 hdr.msg_len = tosend + 1; 1463 drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx); 1464 memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend); 1465 /* add crc at end */ 1466 drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend); 1467 idx += tosend + 1; 1468 1469 ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx); 1470 if (ret) { 1471 DRM_DEBUG_KMS("sideband msg failed to send\n"); 1472 return ret; 1473 } 1474 1475 txmsg->cur_offset += tosend; 1476 if (txmsg->cur_offset == txmsg->cur_len) { 1477 txmsg->state = DRM_DP_SIDEBAND_TX_SENT; 1478 return 1; 1479 } 1480 return 0; 1481} 1482 1483static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr) 1484{ 1485 struct drm_dp_sideband_msg_tx *txmsg; 1486 int ret; 1487 1488 WARN_ON(!mutex_is_locked(&mgr->qlock)); 1489 1490 /* construct a chunk from the first msg in the tx_msg queue */ 1491 if (list_empty(&mgr->tx_msg_downq)) { 1492 mgr->tx_down_in_progress = false; 1493 return; 1494 } 1495 mgr->tx_down_in_progress = true; 1496 1497 txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next); 1498 ret = process_single_tx_qlock(mgr, txmsg, false); 1499 if (ret == 1) { 1500 /* txmsg is sent it should be in the slots now */ 1501 list_del(&txmsg->next); 1502 } else if (ret) { 1503 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret); 1504 list_del(&txmsg->next); 1505 if (txmsg->seqno != -1) 1506 txmsg->dst->tx_slots[txmsg->seqno] = NULL; 1507 txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT; 1508 wake_up(&mgr->tx_waitq); 1509 } 1510 if (list_empty(&mgr->tx_msg_downq)) { 1511 mgr->tx_down_in_progress = false; 1512 return; 1513 } 1514} 1515 1516/* called holding qlock */ 1517static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr, 1518 struct drm_dp_sideband_msg_tx *txmsg) 1519{ 1520 int ret; 1521 1522 /* construct a chunk from the first msg in the tx_msg queue */ 1523 ret = process_single_tx_qlock(mgr, txmsg, true); 1524 1525 if (ret != 1) 1526 DRM_DEBUG_KMS("failed to send msg in q %d\n", ret); 1527 1528 txmsg->dst->tx_slots[txmsg->seqno] = NULL; 1529} 1530 1531static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr, 1532 struct drm_dp_sideband_msg_tx *txmsg) 1533{ 1534 mutex_lock(&mgr->qlock); 1535 list_add_tail(&txmsg->next, &mgr->tx_msg_downq); 1536 if (!mgr->tx_down_in_progress) 1537 process_single_down_tx_qlock(mgr); 1538 mutex_unlock(&mgr->qlock); 1539} 1540 1541static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr, 1542 struct drm_dp_mst_branch *mstb) 1543{ 1544 int len; 1545 struct drm_dp_sideband_msg_tx *txmsg; 1546 int ret; 1547 1548 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1549 if (!txmsg) 1550 return -ENOMEM; 1551 1552 txmsg->dst = mstb; 1553 len = build_link_address(txmsg); 1554 1555 drm_dp_queue_down_tx(mgr, txmsg); 1556 1557 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1558 if (ret > 0) { 1559 int i; 1560 1561 if (txmsg->reply.reply_type == 1) 1562 DRM_DEBUG_KMS("link address nak received\n"); 1563 else { 1564 DRM_DEBUG_KMS("link address reply: %d\n", txmsg->reply.u.link_addr.nports); 1565 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) { 1566 DRM_DEBUG_KMS("port %d: input %d, pdt: %d, pn: %d, dpcd_rev: %02x, mcs: %d, ddps: %d, ldps %d, sdp %d/%d\n", i, 1567 txmsg->reply.u.link_addr.ports[i].input_port, 1568 txmsg->reply.u.link_addr.ports[i].peer_device_type, 1569 txmsg->reply.u.link_addr.ports[i].port_number, 1570 txmsg->reply.u.link_addr.ports[i].dpcd_revision, 1571 txmsg->reply.u.link_addr.ports[i].mcs, 1572 txmsg->reply.u.link_addr.ports[i].ddps, 1573 txmsg->reply.u.link_addr.ports[i].legacy_device_plug_status, 1574 txmsg->reply.u.link_addr.ports[i].num_sdp_streams, 1575 txmsg->reply.u.link_addr.ports[i].num_sdp_stream_sinks); 1576 } 1577 1578 drm_dp_check_mstb_guid(mstb, txmsg->reply.u.link_addr.guid); 1579 1580 for (i = 0; i < txmsg->reply.u.link_addr.nports; i++) { 1581 drm_dp_add_port(mstb, mgr->dev, &txmsg->reply.u.link_addr.ports[i]); 1582 } 1583 (*mgr->cbs->hotplug)(mgr); 1584 } 1585 } else 1586 DRM_DEBUG_KMS("link address failed %d\n", ret); 1587 1588 kfree(txmsg); 1589 return 0; 1590} 1591 1592static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr, 1593 struct drm_dp_mst_branch *mstb, 1594 struct drm_dp_mst_port *port) 1595{ 1596 int len; 1597 struct drm_dp_sideband_msg_tx *txmsg; 1598 int ret; 1599 1600 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1601 if (!txmsg) 1602 return -ENOMEM; 1603 1604 txmsg->dst = mstb; 1605 len = build_enum_path_resources(txmsg, port->port_num); 1606 1607 drm_dp_queue_down_tx(mgr, txmsg); 1608 1609 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1610 if (ret > 0) { 1611 if (txmsg->reply.reply_type == 1) 1612 DRM_DEBUG_KMS("enum path resources nak received\n"); 1613 else { 1614 if (port->port_num != txmsg->reply.u.path_resources.port_number) 1615 DRM_ERROR("got incorrect port in response\n"); 1616 DRM_DEBUG_KMS("enum path resources %d: %d %d\n", txmsg->reply.u.path_resources.port_number, txmsg->reply.u.path_resources.full_payload_bw_number, 1617 txmsg->reply.u.path_resources.avail_payload_bw_number); 1618 port->available_pbn = txmsg->reply.u.path_resources.avail_payload_bw_number; 1619 } 1620 } 1621 1622 kfree(txmsg); 1623 return 0; 1624} 1625 1626static struct drm_dp_mst_port *drm_dp_get_last_connected_port_to_mstb(struct drm_dp_mst_branch *mstb) 1627{ 1628 if (!mstb->port_parent) 1629 return NULL; 1630 1631 if (mstb->port_parent->mstb != mstb) 1632 return mstb->port_parent; 1633 1634 return drm_dp_get_last_connected_port_to_mstb(mstb->port_parent->parent); 1635} 1636 1637static struct drm_dp_mst_branch *drm_dp_get_last_connected_port_and_mstb(struct drm_dp_mst_topology_mgr *mgr, 1638 struct drm_dp_mst_branch *mstb, 1639 int *port_num) 1640{ 1641 struct drm_dp_mst_branch *rmstb = NULL; 1642 struct drm_dp_mst_port *found_port; 1643 mutex_lock(&mgr->lock); 1644 if (mgr->mst_primary) { 1645 found_port = drm_dp_get_last_connected_port_to_mstb(mstb); 1646 1647 if (found_port) { 1648 rmstb = found_port->parent; 1649 kref_get(&rmstb->kref); 1650 *port_num = found_port->port_num; 1651 } 1652 } 1653 mutex_unlock(&mgr->lock); 1654 return rmstb; 1655} 1656 1657static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr, 1658 struct drm_dp_mst_port *port, 1659 int id, 1660 int pbn) 1661{ 1662 struct drm_dp_sideband_msg_tx *txmsg; 1663 struct drm_dp_mst_branch *mstb; 1664 int len, ret, port_num; 1665 1666 port = drm_dp_get_validated_port_ref(mgr, port); 1667 if (!port) 1668 return -EINVAL; 1669 1670 port_num = port->port_num; 1671 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent); 1672 if (!mstb) { 1673 mstb = drm_dp_get_last_connected_port_and_mstb(mgr, port->parent, &port_num); 1674 1675 if (!mstb) { 1676 drm_dp_put_port(port); 1677 return -EINVAL; 1678 } 1679 } 1680 1681 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1682 if (!txmsg) { 1683 ret = -ENOMEM; 1684 goto fail_put; 1685 } 1686 1687 txmsg->dst = mstb; 1688 len = build_allocate_payload(txmsg, port_num, 1689 id, 1690 pbn); 1691 1692 drm_dp_queue_down_tx(mgr, txmsg); 1693 1694 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1695 if (ret > 0) { 1696 if (txmsg->reply.reply_type == 1) { 1697 ret = -EINVAL; 1698 } else 1699 ret = 0; 1700 } 1701 kfree(txmsg); 1702fail_put: 1703 drm_dp_put_mst_branch_device(mstb); 1704 drm_dp_put_port(port); 1705 return ret; 1706} 1707 1708static int drm_dp_create_payload_step1(struct drm_dp_mst_topology_mgr *mgr, 1709 int id, 1710 struct drm_dp_payload *payload) 1711{ 1712 int ret; 1713 1714 ret = drm_dp_dpcd_write_payload(mgr, id, payload); 1715 if (ret < 0) { 1716 payload->payload_state = 0; 1717 return ret; 1718 } 1719 payload->payload_state = DP_PAYLOAD_LOCAL; 1720 return 0; 1721} 1722 1723static int drm_dp_create_payload_step2(struct drm_dp_mst_topology_mgr *mgr, 1724 struct drm_dp_mst_port *port, 1725 int id, 1726 struct drm_dp_payload *payload) 1727{ 1728 int ret; 1729 ret = drm_dp_payload_send_msg(mgr, port, id, port->vcpi.pbn); 1730 if (ret < 0) 1731 return ret; 1732 payload->payload_state = DP_PAYLOAD_REMOTE; 1733 return ret; 1734} 1735 1736static int drm_dp_destroy_payload_step1(struct drm_dp_mst_topology_mgr *mgr, 1737 struct drm_dp_mst_port *port, 1738 int id, 1739 struct drm_dp_payload *payload) 1740{ 1741 DRM_DEBUG_KMS("\n"); 1742 /* its okay for these to fail */ 1743 if (port) { 1744 drm_dp_payload_send_msg(mgr, port, id, 0); 1745 } 1746 1747 drm_dp_dpcd_write_payload(mgr, id, payload); 1748 payload->payload_state = DP_PAYLOAD_DELETE_LOCAL; 1749 return 0; 1750} 1751 1752static int drm_dp_destroy_payload_step2(struct drm_dp_mst_topology_mgr *mgr, 1753 int id, 1754 struct drm_dp_payload *payload) 1755{ 1756 payload->payload_state = 0; 1757 return 0; 1758} 1759 1760/** 1761 * drm_dp_update_payload_part1() - Execute payload update part 1 1762 * @mgr: manager to use. 1763 * 1764 * This iterates over all proposed virtual channels, and tries to 1765 * allocate space in the link for them. For 0->slots transitions, 1766 * this step just writes the VCPI to the MST device. For slots->0 1767 * transitions, this writes the updated VCPIs and removes the 1768 * remote VC payloads. 1769 * 1770 * after calling this the driver should generate ACT and payload 1771 * packets. 1772 */ 1773int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr) 1774{ 1775 int i, j; 1776 int cur_slots = 1; 1777 struct drm_dp_payload req_payload; 1778 struct drm_dp_mst_port *port; 1779 1780 mutex_lock(&mgr->payload_lock); 1781 for (i = 0; i < mgr->max_payloads; i++) { 1782 /* solve the current payloads - compare to the hw ones 1783 - update the hw view */ 1784 req_payload.start_slot = cur_slots; 1785 if (mgr->proposed_vcpis[i]) { 1786 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi); 1787 port = drm_dp_get_validated_port_ref(mgr, port); 1788 if (!port) { 1789 mutex_unlock(&mgr->payload_lock); 1790 return -EINVAL; 1791 } 1792 req_payload.num_slots = mgr->proposed_vcpis[i]->num_slots; 1793 } else { 1794 port = NULL; 1795 req_payload.num_slots = 0; 1796 } 1797 1798 if (mgr->payloads[i].start_slot != req_payload.start_slot) { 1799 mgr->payloads[i].start_slot = req_payload.start_slot; 1800 } 1801 /* work out what is required to happen with this payload */ 1802 if (mgr->payloads[i].num_slots != req_payload.num_slots) { 1803 1804 /* need to push an update for this payload */ 1805 if (req_payload.num_slots) { 1806 drm_dp_create_payload_step1(mgr, mgr->proposed_vcpis[i]->vcpi, &req_payload); 1807 mgr->payloads[i].num_slots = req_payload.num_slots; 1808 } else if (mgr->payloads[i].num_slots) { 1809 mgr->payloads[i].num_slots = 0; 1810 drm_dp_destroy_payload_step1(mgr, port, port->vcpi.vcpi, &mgr->payloads[i]); 1811 req_payload.payload_state = mgr->payloads[i].payload_state; 1812 mgr->payloads[i].start_slot = 0; 1813 } 1814 mgr->payloads[i].payload_state = req_payload.payload_state; 1815 } 1816 cur_slots += req_payload.num_slots; 1817 1818 if (port) 1819 drm_dp_put_port(port); 1820 } 1821 1822 for (i = 0; i < mgr->max_payloads; i++) { 1823 if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) { 1824 DRM_DEBUG_KMS("removing payload %d\n", i); 1825 for (j = i; j < mgr->max_payloads - 1; j++) { 1826 memcpy(&mgr->payloads[j], &mgr->payloads[j + 1], sizeof(struct drm_dp_payload)); 1827 mgr->proposed_vcpis[j] = mgr->proposed_vcpis[j + 1]; 1828 if (mgr->proposed_vcpis[j] && mgr->proposed_vcpis[j]->num_slots) { 1829 set_bit(j + 1, &mgr->payload_mask); 1830 } else { 1831 clear_bit(j + 1, &mgr->payload_mask); 1832 } 1833 } 1834 memset(&mgr->payloads[mgr->max_payloads - 1], 0, sizeof(struct drm_dp_payload)); 1835 mgr->proposed_vcpis[mgr->max_payloads - 1] = NULL; 1836 clear_bit(mgr->max_payloads, &mgr->payload_mask); 1837 1838 } 1839 } 1840 mutex_unlock(&mgr->payload_lock); 1841 1842 return 0; 1843} 1844EXPORT_SYMBOL(drm_dp_update_payload_part1); 1845 1846/** 1847 * drm_dp_update_payload_part2() - Execute payload update part 2 1848 * @mgr: manager to use. 1849 * 1850 * This iterates over all proposed virtual channels, and tries to 1851 * allocate space in the link for them. For 0->slots transitions, 1852 * this step writes the remote VC payload commands. For slots->0 1853 * this just resets some internal state. 1854 */ 1855int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr) 1856{ 1857 struct drm_dp_mst_port *port; 1858 int i; 1859 int ret = 0; 1860 mutex_lock(&mgr->payload_lock); 1861 for (i = 0; i < mgr->max_payloads; i++) { 1862 1863 if (!mgr->proposed_vcpis[i]) 1864 continue; 1865 1866 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi); 1867 1868 DRM_DEBUG_KMS("payload %d %d\n", i, mgr->payloads[i].payload_state); 1869 if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) { 1870 ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]); 1871 } else if (mgr->payloads[i].payload_state == DP_PAYLOAD_DELETE_LOCAL) { 1872 ret = drm_dp_destroy_payload_step2(mgr, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]); 1873 } 1874 if (ret) { 1875 mutex_unlock(&mgr->payload_lock); 1876 return ret; 1877 } 1878 } 1879 mutex_unlock(&mgr->payload_lock); 1880 return 0; 1881} 1882EXPORT_SYMBOL(drm_dp_update_payload_part2); 1883 1884#if 0 /* unused as of yet */ 1885static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr, 1886 struct drm_dp_mst_port *port, 1887 int offset, int size) 1888{ 1889 int len; 1890 struct drm_dp_sideband_msg_tx *txmsg; 1891 1892 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1893 if (!txmsg) 1894 return -ENOMEM; 1895 1896 len = build_dpcd_read(txmsg, port->port_num, 0, 8); 1897 txmsg->dst = port->parent; 1898 1899 drm_dp_queue_down_tx(mgr, txmsg); 1900 1901 return 0; 1902} 1903#endif 1904 1905static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr, 1906 struct drm_dp_mst_port *port, 1907 int offset, int size, u8 *bytes) 1908{ 1909 int len; 1910 int ret; 1911 struct drm_dp_sideband_msg_tx *txmsg; 1912 struct drm_dp_mst_branch *mstb; 1913 1914 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent); 1915 if (!mstb) 1916 return -EINVAL; 1917 1918 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1919 if (!txmsg) { 1920 ret = -ENOMEM; 1921 goto fail_put; 1922 } 1923 1924 len = build_dpcd_write(txmsg, port->port_num, offset, size, bytes); 1925 txmsg->dst = mstb; 1926 1927 drm_dp_queue_down_tx(mgr, txmsg); 1928 1929 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 1930 if (ret > 0) { 1931 if (txmsg->reply.reply_type == 1) { 1932 ret = -EINVAL; 1933 } else 1934 ret = 0; 1935 } 1936 kfree(txmsg); 1937fail_put: 1938 drm_dp_put_mst_branch_device(mstb); 1939 return ret; 1940} 1941 1942static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type) 1943{ 1944 struct drm_dp_sideband_msg_reply_body reply; 1945 1946 reply.reply_type = 1; 1947 reply.req_type = req_type; 1948 drm_dp_encode_sideband_reply(&reply, msg); 1949 return 0; 1950} 1951 1952static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr, 1953 struct drm_dp_mst_branch *mstb, 1954 int req_type, int seqno, bool broadcast) 1955{ 1956 struct drm_dp_sideband_msg_tx *txmsg; 1957 1958 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 1959 if (!txmsg) 1960 return -ENOMEM; 1961 1962 txmsg->dst = mstb; 1963 txmsg->seqno = seqno; 1964 drm_dp_encode_up_ack_reply(txmsg, req_type); 1965 1966 mutex_lock(&mgr->qlock); 1967 1968 process_single_up_tx_qlock(mgr, txmsg); 1969 1970 mutex_unlock(&mgr->qlock); 1971 1972 kfree(txmsg); 1973 return 0; 1974} 1975 1976static bool drm_dp_get_vc_payload_bw(int dp_link_bw, 1977 int dp_link_count, 1978 int *out) 1979{ 1980 switch (dp_link_bw) { 1981 default: 1982 DRM_DEBUG_KMS("invalid link bandwidth in DPCD: %x (link count: %d)\n", 1983 dp_link_bw, dp_link_count); 1984 return false; 1985 1986 case DP_LINK_BW_1_62: 1987 *out = 3 * dp_link_count; 1988 break; 1989 case DP_LINK_BW_2_7: 1990 *out = 5 * dp_link_count; 1991 break; 1992 case DP_LINK_BW_5_4: 1993 *out = 10 * dp_link_count; 1994 break; 1995 } 1996 return true; 1997} 1998 1999/** 2000 * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager 2001 * @mgr: manager to set state for 2002 * @mst_state: true to enable MST on this connector - false to disable. 2003 * 2004 * This is called by the driver when it detects an MST capable device plugged 2005 * into a DP MST capable port, or when a DP MST capable device is unplugged. 2006 */ 2007int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state) 2008{ 2009 int ret = 0; 2010 struct drm_dp_mst_branch *mstb = NULL; 2011 2012 mutex_lock(&mgr->lock); 2013 if (mst_state == mgr->mst_state) 2014 goto out_unlock; 2015 2016 mgr->mst_state = mst_state; 2017 /* set the device into MST mode */ 2018 if (mst_state) { 2019 WARN_ON(mgr->mst_primary); 2020 2021 /* get dpcd info */ 2022 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE); 2023 if (ret != DP_RECEIVER_CAP_SIZE) { 2024 DRM_DEBUG_KMS("failed to read DPCD\n"); 2025 goto out_unlock; 2026 } 2027 2028 if (!drm_dp_get_vc_payload_bw(mgr->dpcd[1], 2029 mgr->dpcd[2] & DP_MAX_LANE_COUNT_MASK, 2030 &mgr->pbn_div)) { 2031 ret = -EINVAL; 2032 goto out_unlock; 2033 } 2034 2035 mgr->total_pbn = 2560; 2036 mgr->total_slots = DIV_ROUND_UP(mgr->total_pbn, mgr->pbn_div); 2037 mgr->avail_slots = mgr->total_slots; 2038 2039 /* add initial branch device at LCT 1 */ 2040 mstb = drm_dp_add_mst_branch_device(1, NULL); 2041 if (mstb == NULL) { 2042 ret = -ENOMEM; 2043 goto out_unlock; 2044 } 2045 mstb->mgr = mgr; 2046 2047 /* give this the main reference */ 2048 mgr->mst_primary = mstb; 2049 kref_get(&mgr->mst_primary->kref); 2050 2051 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 2052 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); 2053 if (ret < 0) { 2054 goto out_unlock; 2055 } 2056 2057 { 2058 struct drm_dp_payload reset_pay; 2059 reset_pay.start_slot = 0; 2060 reset_pay.num_slots = 0x3f; 2061 drm_dp_dpcd_write_payload(mgr, 0, &reset_pay); 2062 } 2063 2064 queue_work(system_long_wq, &mgr->work); 2065 2066 ret = 0; 2067 } else { 2068 /* disable MST on the device */ 2069 mstb = mgr->mst_primary; 2070 mgr->mst_primary = NULL; 2071 /* this can fail if the device is gone */ 2072 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0); 2073 ret = 0; 2074 memset(mgr->payloads, 0, mgr->max_payloads * sizeof(struct drm_dp_payload)); 2075 mgr->payload_mask = 0; 2076 set_bit(0, &mgr->payload_mask); 2077 mgr->vcpi_mask = 0; 2078 } 2079 2080out_unlock: 2081 mutex_unlock(&mgr->lock); 2082 if (mstb) 2083 drm_dp_put_mst_branch_device(mstb); 2084 return ret; 2085 2086} 2087EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst); 2088 2089/** 2090 * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager 2091 * @mgr: manager to suspend 2092 * 2093 * This function tells the MST device that we can't handle UP messages 2094 * anymore. This should stop it from sending any since we are suspended. 2095 */ 2096void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr) 2097{ 2098 mutex_lock(&mgr->lock); 2099 drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 2100 DP_MST_EN | DP_UPSTREAM_IS_SRC); 2101 mutex_unlock(&mgr->lock); 2102 flush_work(&mgr->work); 2103 flush_work(&mgr->destroy_connector_work); 2104} 2105EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend); 2106 2107/** 2108 * drm_dp_mst_topology_mgr_resume() - resume the MST manager 2109 * @mgr: manager to resume 2110 * 2111 * This will fetch DPCD and see if the device is still there, 2112 * if it is, it will rewrite the MSTM control bits, and return. 2113 * 2114 * if the device fails this returns -1, and the driver should do 2115 * a full MST reprobe, in case we were undocked. 2116 */ 2117int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr) 2118{ 2119 int ret = 0; 2120 2121 mutex_lock(&mgr->lock); 2122 2123 if (mgr->mst_primary) { 2124 int sret; 2125 u8 guid[16]; 2126 2127 sret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, mgr->dpcd, DP_RECEIVER_CAP_SIZE); 2128 if (sret != DP_RECEIVER_CAP_SIZE) { 2129 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n"); 2130 ret = -1; 2131 goto out_unlock; 2132 } 2133 2134 ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 2135 DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); 2136 if (ret < 0) { 2137 DRM_DEBUG_KMS("mst write failed - undocked during suspend?\n"); 2138 ret = -1; 2139 goto out_unlock; 2140 } 2141 2142 /* Some hubs forget their guids after they resume */ 2143 sret = drm_dp_dpcd_read(mgr->aux, DP_GUID, guid, 16); 2144 if (sret != 16) { 2145 DRM_DEBUG_KMS("dpcd read failed - undocked during suspend?\n"); 2146 ret = -1; 2147 goto out_unlock; 2148 } 2149 drm_dp_check_mstb_guid(mgr->mst_primary, guid); 2150 2151 ret = 0; 2152 } else 2153 ret = -1; 2154 2155out_unlock: 2156 mutex_unlock(&mgr->lock); 2157 return ret; 2158} 2159EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume); 2160 2161static void drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up) 2162{ 2163 int len; 2164 u8 replyblock[32]; 2165 int replylen, origlen, curreply; 2166 int ret; 2167 struct drm_dp_sideband_msg_rx *msg; 2168 int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE; 2169 msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv; 2170 2171 len = min(mgr->max_dpcd_transaction_bytes, 16); 2172 ret = drm_dp_dpcd_read(mgr->aux, basereg, 2173 replyblock, len); 2174 if (ret != len) { 2175 DRM_DEBUG_KMS("failed to read DPCD down rep %d %d\n", len, ret); 2176 return; 2177 } 2178 ret = drm_dp_sideband_msg_build(msg, replyblock, len, true); 2179 if (!ret) { 2180 DRM_DEBUG_KMS("sideband msg build failed %d\n", replyblock[0]); 2181 return; 2182 } 2183 replylen = msg->curchunk_len + msg->curchunk_hdrlen; 2184 2185 origlen = replylen; 2186 replylen -= len; 2187 curreply = len; 2188 while (replylen > 0) { 2189 len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16); 2190 ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply, 2191 replyblock, len); 2192 if (ret != len) { 2193 DRM_DEBUG_KMS("failed to read a chunk\n"); 2194 } 2195 ret = drm_dp_sideband_msg_build(msg, replyblock, len, false); 2196 if (ret == false) 2197 DRM_DEBUG_KMS("failed to build sideband msg\n"); 2198 curreply += len; 2199 replylen -= len; 2200 } 2201} 2202 2203static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr) 2204{ 2205 int ret = 0; 2206 2207 drm_dp_get_one_sb_msg(mgr, false); 2208 2209 if (mgr->down_rep_recv.have_eomt) { 2210 struct drm_dp_sideband_msg_tx *txmsg; 2211 struct drm_dp_mst_branch *mstb; 2212 int slot = -1; 2213 mstb = drm_dp_get_mst_branch_device(mgr, 2214 mgr->down_rep_recv.initial_hdr.lct, 2215 mgr->down_rep_recv.initial_hdr.rad); 2216 2217 if (!mstb) { 2218 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->down_rep_recv.initial_hdr.lct); 2219 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2220 return 0; 2221 } 2222 2223 /* find the message */ 2224 slot = mgr->down_rep_recv.initial_hdr.seqno; 2225 mutex_lock(&mgr->qlock); 2226 txmsg = mstb->tx_slots[slot]; 2227 /* remove from slots */ 2228 mutex_unlock(&mgr->qlock); 2229 2230 if (!txmsg) { 2231 DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n", 2232 mstb, 2233 mgr->down_rep_recv.initial_hdr.seqno, 2234 mgr->down_rep_recv.initial_hdr.lct, 2235 mgr->down_rep_recv.initial_hdr.rad[0], 2236 mgr->down_rep_recv.msg[0]); 2237 drm_dp_put_mst_branch_device(mstb); 2238 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2239 return 0; 2240 } 2241 2242 drm_dp_sideband_parse_reply(&mgr->down_rep_recv, &txmsg->reply); 2243 if (txmsg->reply.reply_type == 1) { 2244 DRM_DEBUG_KMS("Got NAK reply: req 0x%02x, reason 0x%02x, nak data 0x%02x\n", txmsg->reply.req_type, txmsg->reply.u.nak.reason, txmsg->reply.u.nak.nak_data); 2245 } 2246 2247 memset(&mgr->down_rep_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2248 drm_dp_put_mst_branch_device(mstb); 2249 2250 mutex_lock(&mgr->qlock); 2251 txmsg->state = DRM_DP_SIDEBAND_TX_RX; 2252 mstb->tx_slots[slot] = NULL; 2253 mutex_unlock(&mgr->qlock); 2254 2255 wake_up(&mgr->tx_waitq); 2256 } 2257 return ret; 2258} 2259 2260static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr) 2261{ 2262 int ret = 0; 2263 drm_dp_get_one_sb_msg(mgr, true); 2264 2265 if (mgr->up_req_recv.have_eomt) { 2266 struct drm_dp_sideband_msg_req_body msg; 2267 struct drm_dp_mst_branch *mstb = NULL; 2268 bool seqno; 2269 2270 if (!mgr->up_req_recv.initial_hdr.broadcast) { 2271 mstb = drm_dp_get_mst_branch_device(mgr, 2272 mgr->up_req_recv.initial_hdr.lct, 2273 mgr->up_req_recv.initial_hdr.rad); 2274 if (!mstb) { 2275 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct); 2276 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2277 return 0; 2278 } 2279 } 2280 2281 seqno = mgr->up_req_recv.initial_hdr.seqno; 2282 drm_dp_sideband_parse_req(&mgr->up_req_recv, &msg); 2283 2284 if (msg.req_type == DP_CONNECTION_STATUS_NOTIFY) { 2285 drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false); 2286 2287 if (!mstb) 2288 mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.conn_stat.guid); 2289 2290 if (!mstb) { 2291 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct); 2292 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2293 return 0; 2294 } 2295 2296 drm_dp_update_port(mstb, &msg.u.conn_stat); 2297 2298 DRM_DEBUG_KMS("Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n", msg.u.conn_stat.port_number, msg.u.conn_stat.legacy_device_plug_status, msg.u.conn_stat.displayport_device_plug_status, msg.u.conn_stat.message_capability_status, msg.u.conn_stat.input_port, msg.u.conn_stat.peer_device_type); 2299 (*mgr->cbs->hotplug)(mgr); 2300 2301 } else if (msg.req_type == DP_RESOURCE_STATUS_NOTIFY) { 2302 drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, msg.req_type, seqno, false); 2303 if (!mstb) 2304 mstb = drm_dp_get_mst_branch_device_by_guid(mgr, msg.u.resource_stat.guid); 2305 2306 if (!mstb) { 2307 DRM_DEBUG_KMS("Got MST reply from unknown device %d\n", mgr->up_req_recv.initial_hdr.lct); 2308 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2309 return 0; 2310 } 2311 2312 DRM_DEBUG_KMS("Got RSN: pn: %d avail_pbn %d\n", msg.u.resource_stat.port_number, msg.u.resource_stat.available_pbn); 2313 } 2314 2315 drm_dp_put_mst_branch_device(mstb); 2316 memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); 2317 } 2318 return ret; 2319} 2320 2321/** 2322 * drm_dp_mst_hpd_irq() - MST hotplug IRQ notify 2323 * @mgr: manager to notify irq for. 2324 * @esi: 4 bytes from SINK_COUNT_ESI 2325 * @handled: whether the hpd interrupt was consumed or not 2326 * 2327 * This should be called from the driver when it detects a short IRQ, 2328 * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The 2329 * topology manager will process the sideband messages received as a result 2330 * of this. 2331 */ 2332int drm_dp_mst_hpd_irq(struct drm_dp_mst_topology_mgr *mgr, u8 *esi, bool *handled) 2333{ 2334 int ret = 0; 2335 int sc; 2336 *handled = false; 2337 sc = esi[0] & 0x3f; 2338 2339 if (sc != mgr->sink_count) { 2340 mgr->sink_count = sc; 2341 *handled = true; 2342 } 2343 2344 if (esi[1] & DP_DOWN_REP_MSG_RDY) { 2345 ret = drm_dp_mst_handle_down_rep(mgr); 2346 *handled = true; 2347 } 2348 2349 if (esi[1] & DP_UP_REQ_MSG_RDY) { 2350 ret |= drm_dp_mst_handle_up_req(mgr); 2351 *handled = true; 2352 } 2353 2354 drm_dp_mst_kick_tx(mgr); 2355 return ret; 2356} 2357EXPORT_SYMBOL(drm_dp_mst_hpd_irq); 2358 2359/** 2360 * drm_dp_mst_detect_port() - get connection status for an MST port 2361 * @mgr: manager for this port 2362 * @port: unverified pointer to a port 2363 * 2364 * This returns the current connection state for a port. It validates the 2365 * port pointer still exists so the caller doesn't require a reference 2366 */ 2367enum drm_connector_status drm_dp_mst_detect_port(struct drm_connector *connector, 2368 struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2369{ 2370 enum drm_connector_status status = connector_status_disconnected; 2371 2372 /* we need to search for the port in the mgr in case its gone */ 2373 port = drm_dp_get_validated_port_ref(mgr, port); 2374 if (!port) 2375 return connector_status_disconnected; 2376 2377 if (!port->ddps) 2378 goto out; 2379 2380 switch (port->pdt) { 2381 case DP_PEER_DEVICE_NONE: 2382 case DP_PEER_DEVICE_MST_BRANCHING: 2383 break; 2384 2385 case DP_PEER_DEVICE_SST_SINK: 2386 status = connector_status_connected; 2387 /* for logical ports - cache the EDID */ 2388 if (port->port_num >= 8 && !port->cached_edid) { 2389 port->cached_edid = drm_get_edid(connector, &port->aux.ddc); 2390 } 2391 break; 2392 case DP_PEER_DEVICE_DP_LEGACY_CONV: 2393 if (port->ldps) 2394 status = connector_status_connected; 2395 break; 2396 } 2397out: 2398 drm_dp_put_port(port); 2399 return status; 2400} 2401EXPORT_SYMBOL(drm_dp_mst_detect_port); 2402 2403/** 2404 * drm_dp_mst_get_edid() - get EDID for an MST port 2405 * @connector: toplevel connector to get EDID for 2406 * @mgr: manager for this port 2407 * @port: unverified pointer to a port. 2408 * 2409 * This returns an EDID for the port connected to a connector, 2410 * It validates the pointer still exists so the caller doesn't require a 2411 * reference. 2412 */ 2413struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2414{ 2415 struct edid *edid = NULL; 2416 2417 /* we need to search for the port in the mgr in case its gone */ 2418 port = drm_dp_get_validated_port_ref(mgr, port); 2419 if (!port) 2420 return NULL; 2421 2422 if (port->cached_edid) 2423 edid = drm_edid_duplicate(port->cached_edid); 2424 else 2425 edid = drm_get_edid(connector, &port->aux.ddc); 2426 2427 drm_mode_connector_set_tile_property(connector); 2428 drm_dp_put_port(port); 2429 return edid; 2430} 2431EXPORT_SYMBOL(drm_dp_mst_get_edid); 2432 2433/** 2434 * drm_dp_find_vcpi_slots() - find slots for this PBN value 2435 * @mgr: manager to use 2436 * @pbn: payload bandwidth to convert into slots. 2437 */ 2438int drm_dp_find_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, 2439 int pbn) 2440{ 2441 int num_slots; 2442 2443 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div); 2444 2445 if (num_slots > mgr->avail_slots) 2446 return -ENOSPC; 2447 return num_slots; 2448} 2449EXPORT_SYMBOL(drm_dp_find_vcpi_slots); 2450 2451static int drm_dp_init_vcpi(struct drm_dp_mst_topology_mgr *mgr, 2452 struct drm_dp_vcpi *vcpi, int pbn) 2453{ 2454 int num_slots; 2455 int ret; 2456 2457 num_slots = DIV_ROUND_UP(pbn, mgr->pbn_div); 2458 2459 if (num_slots > mgr->avail_slots) 2460 return -ENOSPC; 2461 2462 vcpi->pbn = pbn; 2463 vcpi->aligned_pbn = num_slots * mgr->pbn_div; 2464 vcpi->num_slots = num_slots; 2465 2466 ret = drm_dp_mst_assign_payload_id(mgr, vcpi); 2467 if (ret < 0) 2468 return ret; 2469 return 0; 2470} 2471 2472/** 2473 * drm_dp_mst_allocate_vcpi() - Allocate a virtual channel 2474 * @mgr: manager for this port 2475 * @port: port to allocate a virtual channel for. 2476 * @pbn: payload bandwidth number to request 2477 * @slots: returned number of slots for this PBN. 2478 */ 2479bool drm_dp_mst_allocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn, int *slots) 2480{ 2481 int ret; 2482 2483 port = drm_dp_get_validated_port_ref(mgr, port); 2484 if (!port) 2485 return false; 2486 2487 if (port->vcpi.vcpi > 0) { 2488 DRM_DEBUG_KMS("payload: vcpi %d already allocated for pbn %d - requested pbn %d\n", port->vcpi.vcpi, port->vcpi.pbn, pbn); 2489 if (pbn == port->vcpi.pbn) { 2490 *slots = port->vcpi.num_slots; 2491 drm_dp_put_port(port); 2492 return true; 2493 } 2494 } 2495 2496 ret = drm_dp_init_vcpi(mgr, &port->vcpi, pbn); 2497 if (ret) { 2498 DRM_DEBUG_KMS("failed to init vcpi %d %d %d\n", DIV_ROUND_UP(pbn, mgr->pbn_div), mgr->avail_slots, ret); 2499 goto out; 2500 } 2501 DRM_DEBUG_KMS("initing vcpi for %d %d\n", pbn, port->vcpi.num_slots); 2502 *slots = port->vcpi.num_slots; 2503 2504 drm_dp_put_port(port); 2505 return true; 2506out: 2507 return false; 2508} 2509EXPORT_SYMBOL(drm_dp_mst_allocate_vcpi); 2510 2511int drm_dp_mst_get_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2512{ 2513 int slots = 0; 2514 port = drm_dp_get_validated_port_ref(mgr, port); 2515 if (!port) 2516 return slots; 2517 2518 slots = port->vcpi.num_slots; 2519 drm_dp_put_port(port); 2520 return slots; 2521} 2522EXPORT_SYMBOL(drm_dp_mst_get_vcpi_slots); 2523 2524/** 2525 * drm_dp_mst_reset_vcpi_slots() - Reset number of slots to 0 for VCPI 2526 * @mgr: manager for this port 2527 * @port: unverified pointer to a port. 2528 * 2529 * This just resets the number of slots for the ports VCPI for later programming. 2530 */ 2531void drm_dp_mst_reset_vcpi_slots(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2532{ 2533 port = drm_dp_get_validated_port_ref(mgr, port); 2534 if (!port) 2535 return; 2536 port->vcpi.num_slots = 0; 2537 drm_dp_put_port(port); 2538} 2539EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots); 2540 2541/** 2542 * drm_dp_mst_deallocate_vcpi() - deallocate a VCPI 2543 * @mgr: manager for this port 2544 * @port: unverified port to deallocate vcpi for 2545 */ 2546void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) 2547{ 2548 port = drm_dp_get_validated_port_ref(mgr, port); 2549 if (!port) 2550 return; 2551 2552 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi); 2553 port->vcpi.num_slots = 0; 2554 port->vcpi.pbn = 0; 2555 port->vcpi.aligned_pbn = 0; 2556 port->vcpi.vcpi = 0; 2557 drm_dp_put_port(port); 2558} 2559EXPORT_SYMBOL(drm_dp_mst_deallocate_vcpi); 2560 2561static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr, 2562 int id, struct drm_dp_payload *payload) 2563{ 2564 u8 payload_alloc[3], status; 2565 int ret; 2566 int retries = 0; 2567 2568 drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, 2569 DP_PAYLOAD_TABLE_UPDATED); 2570 2571 payload_alloc[0] = id; 2572 payload_alloc[1] = payload->start_slot; 2573 payload_alloc[2] = payload->num_slots; 2574 2575 ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3); 2576 if (ret != 3) { 2577 DRM_DEBUG_KMS("failed to write payload allocation %d\n", ret); 2578 goto fail; 2579 } 2580 2581retry: 2582 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status); 2583 if (ret < 0) { 2584 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret); 2585 goto fail; 2586 } 2587 2588 if (!(status & DP_PAYLOAD_TABLE_UPDATED)) { 2589 retries++; 2590 if (retries < 20) { 2591 usleep_range(10000, 20000); 2592 goto retry; 2593 } 2594 DRM_DEBUG_KMS("status not set after read payload table status %d\n", status); 2595 ret = -EINVAL; 2596 goto fail; 2597 } 2598 ret = 0; 2599fail: 2600 return ret; 2601} 2602 2603 2604/** 2605 * drm_dp_check_act_status() - Check ACT handled status. 2606 * @mgr: manager to use 2607 * 2608 * Check the payload status bits in the DPCD for ACT handled completion. 2609 */ 2610int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr) 2611{ 2612 u8 status; 2613 int ret; 2614 int count = 0; 2615 2616 do { 2617 ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status); 2618 2619 if (ret < 0) { 2620 DRM_DEBUG_KMS("failed to read payload table status %d\n", ret); 2621 goto fail; 2622 } 2623 2624 if (status & DP_PAYLOAD_ACT_HANDLED) 2625 break; 2626 count++; 2627 udelay(100); 2628 2629 } while (count < 30); 2630 2631 if (!(status & DP_PAYLOAD_ACT_HANDLED)) { 2632 DRM_DEBUG_KMS("failed to get ACT bit %d after %d retries\n", status, count); 2633 ret = -EINVAL; 2634 goto fail; 2635 } 2636 return 0; 2637fail: 2638 return ret; 2639} 2640EXPORT_SYMBOL(drm_dp_check_act_status); 2641 2642/** 2643 * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode. 2644 * @clock: dot clock for the mode 2645 * @bpp: bpp for the mode. 2646 * 2647 * This uses the formula in the spec to calculate the PBN value for a mode. 2648 */ 2649int drm_dp_calc_pbn_mode(int clock, int bpp) 2650{ 2651 u64 kbps; 2652 s64 peak_kbps; 2653 u32 numerator; 2654 u32 denominator; 2655 2656 kbps = clock * bpp; 2657 2658 /* 2659 * margin 5300ppm + 300ppm ~ 0.6% as per spec, factor is 1.006 2660 * The unit of 54/64Mbytes/sec is an arbitrary unit chosen based on 2661 * common multiplier to render an integer PBN for all link rate/lane 2662 * counts combinations 2663 * calculate 2664 * peak_kbps *= (1006/1000) 2665 * peak_kbps *= (64/54) 2666 * peak_kbps *= 8 convert to bytes 2667 */ 2668 2669 numerator = 64 * 1006; 2670 denominator = 54 * 8 * 1000 * 1000; 2671 2672 kbps *= numerator; 2673 peak_kbps = drm_fixp_from_fraction(kbps, denominator); 2674 2675 return drm_fixp2int_ceil(peak_kbps); 2676} 2677EXPORT_SYMBOL(drm_dp_calc_pbn_mode); 2678 2679static int test_calc_pbn_mode(void) 2680{ 2681 int ret; 2682 ret = drm_dp_calc_pbn_mode(154000, 30); 2683 if (ret != 689) { 2684 DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n", 2685 154000, 30, 689, ret); 2686 return -EINVAL; 2687 } 2688 ret = drm_dp_calc_pbn_mode(234000, 30); 2689 if (ret != 1047) { 2690 DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n", 2691 234000, 30, 1047, ret); 2692 return -EINVAL; 2693 } 2694 ret = drm_dp_calc_pbn_mode(297000, 24); 2695 if (ret != 1063) { 2696 DRM_ERROR("PBN calculation test failed - clock %d, bpp %d, expected PBN %d, actual PBN %d.\n", 2697 297000, 24, 1063, ret); 2698 return -EINVAL; 2699 } 2700 return 0; 2701} 2702 2703/* we want to kick the TX after we've ack the up/down IRQs. */ 2704static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr) 2705{ 2706 queue_work(system_long_wq, &mgr->tx_work); 2707} 2708 2709static void drm_dp_mst_dump_mstb(struct seq_file *m, 2710 struct drm_dp_mst_branch *mstb) 2711{ 2712 struct drm_dp_mst_port *port; 2713 int tabs = mstb->lct; 2714 char prefix[10]; 2715 int i; 2716 2717 for (i = 0; i < tabs; i++) 2718 prefix[i] = '\t'; 2719 prefix[i] = '\0'; 2720 2721 seq_printf(m, "%smst: %p, %d\n", prefix, mstb, mstb->num_ports); 2722 list_for_each_entry(port, &mstb->ports, next) { 2723 seq_printf(m, "%sport: %d: ddps: %d ldps: %d, %p, conn: %p\n", prefix, port->port_num, port->ddps, port->ldps, port, port->connector); 2724 if (port->mstb) 2725 drm_dp_mst_dump_mstb(m, port->mstb); 2726 } 2727} 2728 2729static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr, 2730 char *buf) 2731{ 2732 int ret; 2733 int i; 2734 for (i = 0; i < 4; i++) { 2735 ret = drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + (i * 16), &buf[i * 16], 16); 2736 if (ret != 16) 2737 break; 2738 } 2739 if (i == 4) 2740 return true; 2741 return false; 2742} 2743 2744/** 2745 * drm_dp_mst_dump_topology(): dump topology to seq file. 2746 * @m: seq_file to dump output to 2747 * @mgr: manager to dump current topology for. 2748 * 2749 * helper to dump MST topology to a seq file for debugfs. 2750 */ 2751void drm_dp_mst_dump_topology(struct seq_file *m, 2752 struct drm_dp_mst_topology_mgr *mgr) 2753{ 2754 int i; 2755 struct drm_dp_mst_port *port; 2756 mutex_lock(&mgr->lock); 2757 if (mgr->mst_primary) 2758 drm_dp_mst_dump_mstb(m, mgr->mst_primary); 2759 2760 /* dump VCPIs */ 2761 mutex_unlock(&mgr->lock); 2762 2763 mutex_lock(&mgr->payload_lock); 2764 seq_printf(m, "vcpi: %lx %lx\n", mgr->payload_mask, mgr->vcpi_mask); 2765 2766 for (i = 0; i < mgr->max_payloads; i++) { 2767 if (mgr->proposed_vcpis[i]) { 2768 port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi); 2769 seq_printf(m, "vcpi %d: %d %d %d\n", i, port->port_num, port->vcpi.vcpi, port->vcpi.num_slots); 2770 } else 2771 seq_printf(m, "vcpi %d:unsed\n", i); 2772 } 2773 for (i = 0; i < mgr->max_payloads; i++) { 2774 seq_printf(m, "payload %d: %d, %d, %d\n", 2775 i, 2776 mgr->payloads[i].payload_state, 2777 mgr->payloads[i].start_slot, 2778 mgr->payloads[i].num_slots); 2779 2780 2781 } 2782 mutex_unlock(&mgr->payload_lock); 2783 2784 mutex_lock(&mgr->lock); 2785 if (mgr->mst_primary) { 2786 u8 buf[64]; 2787 bool bret; 2788 int ret; 2789 ret = drm_dp_dpcd_read(mgr->aux, DP_DPCD_REV, buf, DP_RECEIVER_CAP_SIZE); 2790 seq_printf(m, "dpcd: "); 2791 for (i = 0; i < DP_RECEIVER_CAP_SIZE; i++) 2792 seq_printf(m, "%02x ", buf[i]); 2793 seq_printf(m, "\n"); 2794 ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2); 2795 seq_printf(m, "faux/mst: "); 2796 for (i = 0; i < 2; i++) 2797 seq_printf(m, "%02x ", buf[i]); 2798 seq_printf(m, "\n"); 2799 ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1); 2800 seq_printf(m, "mst ctrl: "); 2801 for (i = 0; i < 1; i++) 2802 seq_printf(m, "%02x ", buf[i]); 2803 seq_printf(m, "\n"); 2804 2805 bret = dump_dp_payload_table(mgr, buf); 2806 if (bret == true) { 2807 seq_printf(m, "payload table: "); 2808 for (i = 0; i < 63; i++) 2809 seq_printf(m, "%02x ", buf[i]); 2810 seq_printf(m, "\n"); 2811 } 2812 2813 } 2814 2815 mutex_unlock(&mgr->lock); 2816 2817} 2818EXPORT_SYMBOL(drm_dp_mst_dump_topology); 2819 2820static void drm_dp_tx_work(struct work_struct *work) 2821{ 2822 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work); 2823 2824 mutex_lock(&mgr->qlock); 2825 if (mgr->tx_down_in_progress) 2826 process_single_down_tx_qlock(mgr); 2827 mutex_unlock(&mgr->qlock); 2828} 2829 2830static void drm_dp_free_mst_port(struct kref *kref) 2831{ 2832 struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref); 2833 kref_put(&port->parent->kref, drm_dp_free_mst_branch_device); 2834 kfree(port); 2835} 2836 2837static void drm_dp_destroy_connector_work(struct work_struct *work) 2838{ 2839 struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, destroy_connector_work); 2840 struct drm_dp_mst_port *port; 2841 bool send_hotplug = false; 2842 /* 2843 * Not a regular list traverse as we have to drop the destroy 2844 * connector lock before destroying the connector, to avoid AB->BA 2845 * ordering between this lock and the config mutex. 2846 */ 2847 for (;;) { 2848 mutex_lock(&mgr->destroy_connector_lock); 2849 port = list_first_entry_or_null(&mgr->destroy_connector_list, struct drm_dp_mst_port, next); 2850 if (!port) { 2851 mutex_unlock(&mgr->destroy_connector_lock); 2852 break; 2853 } 2854 list_del(&port->next); 2855 mutex_unlock(&mgr->destroy_connector_lock); 2856 2857 kref_init(&port->kref); 2858 INIT_LIST_HEAD(&port->next); 2859 2860 mgr->cbs->destroy_connector(mgr, port->connector); 2861 2862 drm_dp_port_teardown_pdt(port, port->pdt); 2863 2864 if (!port->input && port->vcpi.vcpi > 0) { 2865 if (mgr->mst_state) { 2866 drm_dp_mst_reset_vcpi_slots(mgr, port); 2867 drm_dp_update_payload_part1(mgr); 2868 drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi); 2869 } 2870 } 2871 2872 kref_put(&port->kref, drm_dp_free_mst_port); 2873 send_hotplug = true; 2874 } 2875 if (send_hotplug) 2876 (*mgr->cbs->hotplug)(mgr); 2877} 2878 2879/** 2880 * drm_dp_mst_topology_mgr_init - initialise a topology manager 2881 * @mgr: manager struct to initialise 2882 * @dev: device providing this structure - for i2c addition. 2883 * @aux: DP helper aux channel to talk to this device 2884 * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit 2885 * @max_payloads: maximum number of payloads this GPU can source 2886 * @conn_base_id: the connector object ID the MST device is connected to. 2887 * 2888 * Return 0 for success, or negative error code on failure 2889 */ 2890int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, 2891 struct device *dev, struct drm_dp_aux *aux, 2892 int max_dpcd_transaction_bytes, 2893 int max_payloads, int conn_base_id) 2894{ 2895 mutex_init(&mgr->lock); 2896 mutex_init(&mgr->qlock); 2897 mutex_init(&mgr->payload_lock); 2898 mutex_init(&mgr->destroy_connector_lock); 2899 INIT_LIST_HEAD(&mgr->tx_msg_downq); 2900 INIT_LIST_HEAD(&mgr->destroy_connector_list); 2901 INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work); 2902 INIT_WORK(&mgr->tx_work, drm_dp_tx_work); 2903 INIT_WORK(&mgr->destroy_connector_work, drm_dp_destroy_connector_work); 2904 init_waitqueue_head(&mgr->tx_waitq); 2905 mgr->dev = dev; 2906 mgr->aux = aux; 2907 mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes; 2908 mgr->max_payloads = max_payloads; 2909 mgr->conn_base_id = conn_base_id; 2910 mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL); 2911 if (!mgr->payloads) 2912 return -ENOMEM; 2913 mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL); 2914 if (!mgr->proposed_vcpis) 2915 return -ENOMEM; 2916 set_bit(0, &mgr->payload_mask); 2917 test_calc_pbn_mode(); 2918 return 0; 2919} 2920EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init); 2921 2922/** 2923 * drm_dp_mst_topology_mgr_destroy() - destroy topology manager. 2924 * @mgr: manager to destroy 2925 */ 2926void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr) 2927{ 2928 flush_work(&mgr->work); 2929 flush_work(&mgr->destroy_connector_work); 2930 mutex_lock(&mgr->payload_lock); 2931 kfree(mgr->payloads); 2932 mgr->payloads = NULL; 2933 kfree(mgr->proposed_vcpis); 2934 mgr->proposed_vcpis = NULL; 2935 mutex_unlock(&mgr->payload_lock); 2936 mgr->dev = NULL; 2937 mgr->aux = NULL; 2938} 2939EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy); 2940 2941/* I2C device */ 2942static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, 2943 int num) 2944{ 2945 struct drm_dp_aux *aux = adapter->algo_data; 2946 struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux); 2947 struct drm_dp_mst_branch *mstb; 2948 struct drm_dp_mst_topology_mgr *mgr = port->mgr; 2949 unsigned int i; 2950 bool reading = false; 2951 struct drm_dp_sideband_msg_req_body msg; 2952 struct drm_dp_sideband_msg_tx *txmsg = NULL; 2953 int ret; 2954 2955 mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent); 2956 if (!mstb) 2957 return -EREMOTEIO; 2958 2959 /* construct i2c msg */ 2960 /* see if last msg is a read */ 2961 if (msgs[num - 1].flags & I2C_M_RD) 2962 reading = true; 2963 2964 if (!reading || (num - 1 > DP_REMOTE_I2C_READ_MAX_TRANSACTIONS)) { 2965 DRM_DEBUG_KMS("Unsupported I2C transaction for MST device\n"); 2966 ret = -EIO; 2967 goto out; 2968 } 2969 2970 memset(&msg, 0, sizeof(msg)); 2971 msg.req_type = DP_REMOTE_I2C_READ; 2972 msg.u.i2c_read.num_transactions = num - 1; 2973 msg.u.i2c_read.port_number = port->port_num; 2974 for (i = 0; i < num - 1; i++) { 2975 msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr; 2976 msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len; 2977 msg.u.i2c_read.transactions[i].bytes = msgs[i].buf; 2978 } 2979 msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr; 2980 msg.u.i2c_read.num_bytes_read = msgs[num - 1].len; 2981 2982 txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); 2983 if (!txmsg) { 2984 ret = -ENOMEM; 2985 goto out; 2986 } 2987 2988 txmsg->dst = mstb; 2989 drm_dp_encode_sideband_req(&msg, txmsg); 2990 2991 drm_dp_queue_down_tx(mgr, txmsg); 2992 2993 ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); 2994 if (ret > 0) { 2995 2996 if (txmsg->reply.reply_type == 1) { /* got a NAK back */ 2997 ret = -EREMOTEIO; 2998 goto out; 2999 } 3000 if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) { 3001 ret = -EIO; 3002 goto out; 3003 } 3004 memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len); 3005 ret = num; 3006 } 3007out: 3008 kfree(txmsg); 3009 drm_dp_put_mst_branch_device(mstb); 3010 return ret; 3011} 3012 3013static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter) 3014{ 3015 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | 3016 I2C_FUNC_SMBUS_READ_BLOCK_DATA | 3017 I2C_FUNC_SMBUS_BLOCK_PROC_CALL | 3018 I2C_FUNC_10BIT_ADDR; 3019} 3020 3021static const struct i2c_algorithm drm_dp_mst_i2c_algo = { 3022 .functionality = drm_dp_mst_i2c_functionality, 3023 .master_xfer = drm_dp_mst_i2c_xfer, 3024}; 3025 3026/** 3027 * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX 3028 * @aux: DisplayPort AUX channel 3029 * 3030 * Returns 0 on success or a negative error code on failure. 3031 */ 3032static int drm_dp_mst_register_i2c_bus(struct drm_dp_aux *aux) 3033{ 3034 aux->ddc.algo = &drm_dp_mst_i2c_algo; 3035 aux->ddc.algo_data = aux; 3036 aux->ddc.retries = 3; 3037 3038 aux->ddc.class = I2C_CLASS_DDC; 3039 aux->ddc.owner = THIS_MODULE; 3040 aux->ddc.dev.parent = aux->dev; 3041 aux->ddc.dev.of_node = aux->dev->of_node; 3042 3043 strlcpy(aux->ddc.name, aux->name ? aux->name : dev_name(aux->dev), 3044 sizeof(aux->ddc.name)); 3045 3046 return i2c_add_adapter(&aux->ddc); 3047} 3048 3049/** 3050 * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter 3051 * @aux: DisplayPort AUX channel 3052 */ 3053static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_aux *aux) 3054{ 3055 i2c_del_adapter(&aux->ddc); 3056} 3057