drivers/net/can/cc770/cc770.c

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
intid2obj
enable_all_objs
disable_all_objs
set_reset_mode
set_normal_mode
chipset_init
cc770_probe_chip
cc770_start
cc770_set_mode
cc770_set_bittiming
cc770_get_berr_counter
cc770_tx
cc770_start_xmit
cc770_rx
cc770_err
cc770_status_interrupt
cc770_rx_interrupt
cc770_rtr_interrupt
cc770_tx_interrupt
cc770_interrupt
cc770_open
cc770_close
alloc_cc770dev
free_cc770dev
register_cc770dev
unregister_cc770dev
cc770_init
cc770_exit
   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Core driver for the CC770 and AN82527 CAN controllers
   4  *
   5  * Copyright (C) 2009, 2011 Wolfgang Grandegger <wg@grandegger.com>
   6  */
   7 
   8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9 
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/kernel.h>
  13 #include <linux/sched.h>
  14 #include <linux/types.h>
  15 #include <linux/fcntl.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/ptrace.h>
  18 #include <linux/string.h>
  19 #include <linux/errno.h>
  20 #include <linux/netdevice.h>
  21 #include <linux/if_arp.h>
  22 #include <linux/if_ether.h>
  23 #include <linux/skbuff.h>
  24 #include <linux/delay.h>
  25 
  26 #include <linux/can.h>
  27 #include <linux/can/dev.h>
  28 #include <linux/can/error.h>
  29 #include <linux/can/platform/cc770.h>
  30 
  31 #include "cc770.h"
  32 
  33 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
  34 MODULE_LICENSE("GPL v2");
  35 MODULE_DESCRIPTION(KBUILD_MODNAME "CAN netdevice driver");
  36 
  37 /*
  38  * The CC770 is a CAN controller from Bosch, which is 100% compatible
  39  * with the AN82527 from Intel, but with "bugs" being fixed and some
  40  * additional functionality, mainly:
  41  *
  42  * 1. RX and TX error counters are readable.
  43  * 2. Support of silent (listen-only) mode.
  44  * 3. Message object 15 can receive all types of frames, also RTR and EFF.
  45  *
  46  * Details are available from Bosch's "CC770_Product_Info_2007-01.pdf",
  47  * which explains in detail the compatibility between the CC770 and the
  48  * 82527. This driver use the additional functionality 3. on real CC770
  49  * devices. Unfortunately, the CC770 does still not store the message
  50  * identifier of received remote transmission request frames and
  51  * therefore it's set to 0.
  52  *
  53  * The message objects 1..14 can be used for TX and RX while the message
  54  * objects 15 is optimized for RX. It has a shadow register for reliable
  55  * data reception under heavy bus load. Therefore it makes sense to use
  56  * this message object for the needed use case. The frame type (EFF/SFF)
  57  * for the message object 15 can be defined via kernel module parameter
  58  * "msgobj15_eff". If not equal 0, it will receive 29-bit EFF frames,
  59  * otherwise 11 bit SFF messages.
  60  */
  61 static int msgobj15_eff;
  62 module_param(msgobj15_eff, int, 0444);
  63 MODULE_PARM_DESC(msgobj15_eff, "Extended 29-bit frames for message object 15 "
  64                  "(default: 11-bit standard frames)");
  65 
  66 static int i82527_compat;
  67 module_param(i82527_compat, int, 0444);
  68 MODULE_PARM_DESC(i82527_compat, "Strict Intel 82527 compatibility mode "
  69                  "without using additional functions");
  70 
  71 /*
  72  * This driver uses the last 5 message objects 11..15. The definitions
  73  * and structure below allows to configure and assign them to the real
  74  * message object.
  75  */
  76 static unsigned char cc770_obj_flags[CC770_OBJ_MAX] = {
  77         [CC770_OBJ_RX0] = CC770_OBJ_FLAG_RX,
  78         [CC770_OBJ_RX1] = CC770_OBJ_FLAG_RX | CC770_OBJ_FLAG_EFF,
  79         [CC770_OBJ_RX_RTR0] = CC770_OBJ_FLAG_RX | CC770_OBJ_FLAG_RTR,
  80         [CC770_OBJ_RX_RTR1] = CC770_OBJ_FLAG_RX | CC770_OBJ_FLAG_RTR |
  81                               CC770_OBJ_FLAG_EFF,
  82         [CC770_OBJ_TX] = 0,
  83 };
  84 
  85 static const struct can_bittiming_const cc770_bittiming_const = {
  86         .name = KBUILD_MODNAME,
  87         .tseg1_min = 1,
  88         .tseg1_max = 16,
  89         .tseg2_min = 1,
  90         .tseg2_max = 8,
  91         .sjw_max = 4,
  92         .brp_min = 1,
  93         .brp_max = 64,
  94         .brp_inc = 1,
  95 };
  96 
  97 static inline int intid2obj(unsigned int intid)
  98 {
  99         if (intid == 2)
 100                 return 0;
 101         else
 102                 return MSGOBJ_LAST + 2 - intid;
 103 }
 104 
 105 static void enable_all_objs(const struct net_device *dev)
 106 {
 107         struct cc770_priv *priv = netdev_priv(dev);
 108         u8 msgcfg;
 109         unsigned char obj_flags;
 110         unsigned int o, mo;
 111 
 112         for (o = 0; o < ARRAY_SIZE(priv->obj_flags); o++) {
 113                 obj_flags = priv->obj_flags[o];
 114                 mo = obj2msgobj(o);
 115 
 116                 if (obj_flags & CC770_OBJ_FLAG_RX) {
 117                         /*
 118                          * We don't need extra objects for RTR and EFF if
 119                          * the additional CC770 functions are enabled.
 120                          */
 121                         if (priv->control_normal_mode & CTRL_EAF) {
 122                                 if (o > 0)
 123                                         continue;
 124                                 netdev_dbg(dev, "Message object %d for "
 125                                            "RX data, RTR, SFF and EFF\n", mo);
 126                         } else {
 127                                 netdev_dbg(dev,
 128                                            "Message object %d for RX %s %s\n",
 129                                            mo, obj_flags & CC770_OBJ_FLAG_RTR ?
 130                                            "RTR" : "data",
 131                                            obj_flags & CC770_OBJ_FLAG_EFF ?
 132                                            "EFF" : "SFF");
 133                         }
 134 
 135                         if (obj_flags & CC770_OBJ_FLAG_EFF)
 136                                 msgcfg = MSGCFG_XTD;
 137                         else
 138                                 msgcfg = 0;
 139                         if (obj_flags & CC770_OBJ_FLAG_RTR)
 140                                 msgcfg |= MSGCFG_DIR;
 141 
 142                         cc770_write_reg(priv, msgobj[mo].config, msgcfg);
 143                         cc770_write_reg(priv, msgobj[mo].ctrl0,
 144                                         MSGVAL_SET | TXIE_RES |
 145                                         RXIE_SET | INTPND_RES);
 146 
 147                         if (obj_flags & CC770_OBJ_FLAG_RTR)
 148                                 cc770_write_reg(priv, msgobj[mo].ctrl1,
 149                                                 NEWDAT_RES | CPUUPD_SET |
 150                                                 TXRQST_RES | RMTPND_RES);
 151                         else
 152                                 cc770_write_reg(priv, msgobj[mo].ctrl1,
 153                                                 NEWDAT_RES | MSGLST_RES |
 154                                                 TXRQST_RES | RMTPND_RES);
 155                 } else {
 156                         netdev_dbg(dev, "Message object %d for "
 157                                    "TX data, RTR, SFF and EFF\n", mo);
 158 
 159                         cc770_write_reg(priv, msgobj[mo].ctrl1,
 160                                         RMTPND_RES | TXRQST_RES |
 161                                         CPUUPD_RES | NEWDAT_RES);
 162                         cc770_write_reg(priv, msgobj[mo].ctrl0,
 163                                         MSGVAL_RES | TXIE_RES |
 164                                         RXIE_RES | INTPND_RES);
 165                 }
 166         }
 167 }
 168 
 169 static void disable_all_objs(const struct cc770_priv *priv)
 170 {
 171         int o, mo;
 172 
 173         for (o = 0; o <  ARRAY_SIZE(priv->obj_flags); o++) {
 174                 mo = obj2msgobj(o);
 175 
 176                 if (priv->obj_flags[o] & CC770_OBJ_FLAG_RX) {
 177                         if (o > 0 && priv->control_normal_mode & CTRL_EAF)
 178                                 continue;
 179 
 180                         cc770_write_reg(priv, msgobj[mo].ctrl1,
 181                                         NEWDAT_RES | MSGLST_RES |
 182                                         TXRQST_RES | RMTPND_RES);
 183                         cc770_write_reg(priv, msgobj[mo].ctrl0,
 184                                         MSGVAL_RES | TXIE_RES |
 185                                         RXIE_RES | INTPND_RES);
 186                 } else {
 187                         /* Clear message object for send */
 188                         cc770_write_reg(priv, msgobj[mo].ctrl1,
 189                                         RMTPND_RES | TXRQST_RES |
 190                                         CPUUPD_RES | NEWDAT_RES);
 191                         cc770_write_reg(priv, msgobj[mo].ctrl0,
 192                                         MSGVAL_RES | TXIE_RES |
 193                                         RXIE_RES | INTPND_RES);
 194                 }
 195         }
 196 }
 197 
 198 static void set_reset_mode(struct net_device *dev)
 199 {
 200         struct cc770_priv *priv = netdev_priv(dev);
 201 
 202         /* Enable configuration and puts chip in bus-off, disable interrupts */
 203         cc770_write_reg(priv, control, CTRL_CCE | CTRL_INI);
 204 
 205         priv->can.state = CAN_STATE_STOPPED;
 206 
 207         /* Clear interrupts */
 208         cc770_read_reg(priv, interrupt);
 209 
 210         /* Clear status register */
 211         cc770_write_reg(priv, status, 0);
 212 
 213         /* Disable all used message objects */
 214         disable_all_objs(priv);
 215 }
 216 
 217 static void set_normal_mode(struct net_device *dev)
 218 {
 219         struct cc770_priv *priv = netdev_priv(dev);
 220 
 221         /* Clear interrupts */
 222         cc770_read_reg(priv, interrupt);
 223 
 224         /* Clear status register and pre-set last error code */
 225         cc770_write_reg(priv, status, STAT_LEC_MASK);
 226 
 227         /* Enable all used message objects*/
 228         enable_all_objs(dev);
 229 
 230         /*
 231          * Clear bus-off, interrupts only for errors,
 232          * not for status change
 233          */
 234         cc770_write_reg(priv, control, priv->control_normal_mode);
 235 
 236         priv->can.state = CAN_STATE_ERROR_ACTIVE;
 237 }
 238 
 239 static void chipset_init(struct cc770_priv *priv)
 240 {
 241         int mo, id, data;
 242 
 243         /* Enable configuration and put chip in bus-off, disable interrupts */
 244         cc770_write_reg(priv, control, (CTRL_CCE | CTRL_INI));
 245 
 246         /* Set CLKOUT divider and slew rates */
 247         cc770_write_reg(priv, clkout, priv->clkout);
 248 
 249         /* Configure CPU interface / CLKOUT enable */
 250         cc770_write_reg(priv, cpu_interface, priv->cpu_interface);
 251 
 252         /* Set bus configuration  */
 253         cc770_write_reg(priv, bus_config, priv->bus_config);
 254 
 255         /* Clear interrupts */
 256         cc770_read_reg(priv, interrupt);
 257 
 258         /* Clear status register */
 259         cc770_write_reg(priv, status, 0);
 260 
 261         /* Clear and invalidate message objects */
 262         for (mo = MSGOBJ_FIRST; mo <= MSGOBJ_LAST; mo++) {
 263                 cc770_write_reg(priv, msgobj[mo].ctrl0,
 264                                 INTPND_UNC | RXIE_RES |
 265                                 TXIE_RES | MSGVAL_RES);
 266                 cc770_write_reg(priv, msgobj[mo].ctrl0,
 267                                 INTPND_RES | RXIE_RES |
 268                                 TXIE_RES | MSGVAL_RES);
 269                 cc770_write_reg(priv, msgobj[mo].ctrl1,
 270                                 NEWDAT_RES | MSGLST_RES |
 271                                 TXRQST_RES | RMTPND_RES);
 272                 for (data = 0; data < 8; data++)
 273                         cc770_write_reg(priv, msgobj[mo].data[data], 0);
 274                 for (id = 0; id < 4; id++)
 275                         cc770_write_reg(priv, msgobj[mo].id[id], 0);
 276                 cc770_write_reg(priv, msgobj[mo].config, 0);
 277         }
 278 
 279         /* Set all global ID masks to "don't care" */
 280         cc770_write_reg(priv, global_mask_std[0], 0);
 281         cc770_write_reg(priv, global_mask_std[1], 0);
 282         cc770_write_reg(priv, global_mask_ext[0], 0);
 283         cc770_write_reg(priv, global_mask_ext[1], 0);
 284         cc770_write_reg(priv, global_mask_ext[2], 0);
 285         cc770_write_reg(priv, global_mask_ext[3], 0);
 286 
 287 }
 288 
 289 static int cc770_probe_chip(struct net_device *dev)
 290 {
 291         struct cc770_priv *priv = netdev_priv(dev);
 292 
 293         /* Enable configuration, put chip in bus-off, disable ints */
 294         cc770_write_reg(priv, control, CTRL_CCE | CTRL_EAF | CTRL_INI);
 295         /* Configure cpu interface / CLKOUT disable */
 296         cc770_write_reg(priv, cpu_interface, priv->cpu_interface);
 297 
 298         /*
 299          * Check if hardware reset is still inactive or maybe there
 300          * is no chip in this address space
 301          */
 302         if (cc770_read_reg(priv, cpu_interface) & CPUIF_RST) {
 303                 netdev_info(dev, "probing @0x%p failed (reset)\n",
 304                             priv->reg_base);
 305                 return -ENODEV;
 306         }
 307 
 308         /* Write and read back test pattern (some arbitrary values) */
 309         cc770_write_reg(priv, msgobj[1].data[1], 0x25);
 310         cc770_write_reg(priv, msgobj[2].data[3], 0x52);
 311         cc770_write_reg(priv, msgobj[10].data[6], 0xc3);
 312         if ((cc770_read_reg(priv, msgobj[1].data[1]) != 0x25) ||
 313             (cc770_read_reg(priv, msgobj[2].data[3]) != 0x52) ||
 314             (cc770_read_reg(priv, msgobj[10].data[6]) != 0xc3)) {
 315                 netdev_info(dev, "probing @0x%p failed (pattern)\n",
 316                             priv->reg_base);
 317                 return -ENODEV;
 318         }
 319 
 320         /* Check if this chip is a CC770 supporting additional functions */
 321         if (cc770_read_reg(priv, control) & CTRL_EAF)
 322                 priv->control_normal_mode |= CTRL_EAF;
 323 
 324         return 0;
 325 }
 326 
 327 static void cc770_start(struct net_device *dev)
 328 {
 329         struct cc770_priv *priv = netdev_priv(dev);
 330 
 331         /* leave reset mode */
 332         if (priv->can.state != CAN_STATE_STOPPED)
 333                 set_reset_mode(dev);
 334 
 335         /* leave reset mode */
 336         set_normal_mode(dev);
 337 }
 338 
 339 static int cc770_set_mode(struct net_device *dev, enum can_mode mode)
 340 {
 341         switch (mode) {
 342         case CAN_MODE_START:
 343                 cc770_start(dev);
 344                 netif_wake_queue(dev);
 345                 break;
 346 
 347         default:
 348                 return -EOPNOTSUPP;
 349         }
 350 
 351         return 0;
 352 }
 353 
 354 static int cc770_set_bittiming(struct net_device *dev)
 355 {
 356         struct cc770_priv *priv = netdev_priv(dev);
 357         struct can_bittiming *bt = &priv->can.bittiming;
 358         u8 btr0, btr1;
 359 
 360         btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
 361         btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
 362                 (((bt->phase_seg2 - 1) & 0x7) << 4);
 363         if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
 364                 btr1 |= 0x80;
 365 
 366         netdev_info(dev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
 367 
 368         cc770_write_reg(priv, bit_timing_0, btr0);
 369         cc770_write_reg(priv, bit_timing_1, btr1);
 370 
 371         return 0;
 372 }
 373 
 374 static int cc770_get_berr_counter(const struct net_device *dev,
 375                                   struct can_berr_counter *bec)
 376 {
 377         struct cc770_priv *priv = netdev_priv(dev);
 378 
 379         bec->txerr = cc770_read_reg(priv, tx_error_counter);
 380         bec->rxerr = cc770_read_reg(priv, rx_error_counter);
 381 
 382         return 0;
 383 }
 384 
 385 static void cc770_tx(struct net_device *dev, int mo)
 386 {
 387         struct cc770_priv *priv = netdev_priv(dev);
 388         struct can_frame *cf = (struct can_frame *)priv->tx_skb->data;
 389         u8 dlc, rtr;
 390         u32 id;
 391         int i;
 392 
 393         dlc = cf->can_dlc;
 394         id = cf->can_id;
 395         rtr = cf->can_id & CAN_RTR_FLAG ? 0 : MSGCFG_DIR;
 396 
 397         cc770_write_reg(priv, msgobj[mo].ctrl0,
 398                         MSGVAL_RES | TXIE_RES | RXIE_RES | INTPND_RES);
 399         cc770_write_reg(priv, msgobj[mo].ctrl1,
 400                         RMTPND_RES | TXRQST_RES | CPUUPD_SET | NEWDAT_RES);
 401 
 402         if (id & CAN_EFF_FLAG) {
 403                 id &= CAN_EFF_MASK;
 404                 cc770_write_reg(priv, msgobj[mo].config,
 405                                 (dlc << 4) | rtr | MSGCFG_XTD);
 406                 cc770_write_reg(priv, msgobj[mo].id[3], id << 3);
 407                 cc770_write_reg(priv, msgobj[mo].id[2], id >> 5);
 408                 cc770_write_reg(priv, msgobj[mo].id[1], id >> 13);
 409                 cc770_write_reg(priv, msgobj[mo].id[0], id >> 21);
 410         } else {
 411                 id &= CAN_SFF_MASK;
 412                 cc770_write_reg(priv, msgobj[mo].config, (dlc << 4) | rtr);
 413                 cc770_write_reg(priv, msgobj[mo].id[0], id >> 3);
 414                 cc770_write_reg(priv, msgobj[mo].id[1], id << 5);
 415         }
 416 
 417         for (i = 0; i < dlc; i++)
 418                 cc770_write_reg(priv, msgobj[mo].data[i], cf->data[i]);
 419 
 420         cc770_write_reg(priv, msgobj[mo].ctrl1,
 421                         RMTPND_UNC | TXRQST_SET | CPUUPD_RES | NEWDAT_UNC);
 422         cc770_write_reg(priv, msgobj[mo].ctrl0,
 423                         MSGVAL_SET | TXIE_SET | RXIE_SET | INTPND_UNC);
 424 }
 425 
 426 static netdev_tx_t cc770_start_xmit(struct sk_buff *skb, struct net_device *dev)
 427 {
 428         struct cc770_priv *priv = netdev_priv(dev);
 429         unsigned int mo = obj2msgobj(CC770_OBJ_TX);
 430 
 431         if (can_dropped_invalid_skb(dev, skb))
 432                 return NETDEV_TX_OK;
 433 
 434         netif_stop_queue(dev);
 435 
 436         if ((cc770_read_reg(priv,
 437                             msgobj[mo].ctrl1) & TXRQST_UNC) == TXRQST_SET) {
 438                 netdev_err(dev, "TX register is still occupied!\n");
 439                 return NETDEV_TX_BUSY;
 440         }
 441 
 442         priv->tx_skb = skb;
 443         cc770_tx(dev, mo);
 444 
 445         return NETDEV_TX_OK;
 446 }
 447 
 448 static void cc770_rx(struct net_device *dev, unsigned int mo, u8 ctrl1)
 449 {
 450         struct cc770_priv *priv = netdev_priv(dev);
 451         struct net_device_stats *stats = &dev->stats;
 452         struct can_frame *cf;
 453         struct sk_buff *skb;
 454         u8 config;
 455         u32 id;
 456         int i;
 457 
 458         skb = alloc_can_skb(dev, &cf);
 459         if (!skb)
 460                 return;
 461 
 462         config = cc770_read_reg(priv, msgobj[mo].config);
 463 
 464         if (ctrl1 & RMTPND_SET) {
 465                 /*
 466                  * Unfortunately, the chip does not store the real message
 467                  * identifier of the received remote transmission request
 468                  * frame. Therefore we set it to 0.
 469                  */
 470                 cf->can_id = CAN_RTR_FLAG;
 471                 if (config & MSGCFG_XTD)
 472                         cf->can_id |= CAN_EFF_FLAG;
 473                 cf->can_dlc = 0;
 474         } else {
 475                 if (config & MSGCFG_XTD) {
 476                         id = cc770_read_reg(priv, msgobj[mo].id[3]);
 477                         id |= cc770_read_reg(priv, msgobj[mo].id[2]) << 8;
 478                         id |= cc770_read_reg(priv, msgobj[mo].id[1]) << 16;
 479                         id |= cc770_read_reg(priv, msgobj[mo].id[0]) << 24;
 480                         id >>= 3;
 481                         id |= CAN_EFF_FLAG;
 482                 } else {
 483                         id = cc770_read_reg(priv, msgobj[mo].id[1]);
 484                         id |= cc770_read_reg(priv, msgobj[mo].id[0]) << 8;
 485                         id >>= 5;
 486                 }
 487 
 488                 cf->can_id = id;
 489                 cf->can_dlc = get_can_dlc((config & 0xf0) >> 4);
 490                 for (i = 0; i < cf->can_dlc; i++)
 491                         cf->data[i] = cc770_read_reg(priv, msgobj[mo].data[i]);
 492         }
 493 
 494         stats->rx_packets++;
 495         stats->rx_bytes += cf->can_dlc;
 496         netif_rx(skb);
 497 }
 498 
 499 static int cc770_err(struct net_device *dev, u8 status)
 500 {
 501         struct cc770_priv *priv = netdev_priv(dev);
 502         struct net_device_stats *stats = &dev->stats;
 503         struct can_frame *cf;
 504         struct sk_buff *skb;
 505         u8 lec;
 506 
 507         netdev_dbg(dev, "status interrupt (%#x)\n", status);
 508 
 509         skb = alloc_can_err_skb(dev, &cf);
 510         if (!skb)
 511                 return -ENOMEM;
 512 
 513         /* Use extended functions of the CC770 */
 514         if (priv->control_normal_mode & CTRL_EAF) {
 515                 cf->data[6] = cc770_read_reg(priv, tx_error_counter);
 516                 cf->data[7] = cc770_read_reg(priv, rx_error_counter);
 517         }
 518 
 519         if (status & STAT_BOFF) {
 520                 /* Disable interrupts */
 521                 cc770_write_reg(priv, control, CTRL_INI);
 522                 cf->can_id |= CAN_ERR_BUSOFF;
 523                 priv->can.state = CAN_STATE_BUS_OFF;
 524                 priv->can.can_stats.bus_off++;
 525                 can_bus_off(dev);
 526         } else if (status & STAT_WARN) {
 527                 cf->can_id |= CAN_ERR_CRTL;
 528                 /* Only the CC770 does show error passive */
 529                 if (cf->data[7] > 127) {
 530                         cf->data[1] = CAN_ERR_CRTL_RX_PASSIVE |
 531                                 CAN_ERR_CRTL_TX_PASSIVE;
 532                         priv->can.state = CAN_STATE_ERROR_PASSIVE;
 533                         priv->can.can_stats.error_passive++;
 534                 } else {
 535                         cf->data[1] = CAN_ERR_CRTL_RX_WARNING |
 536                                 CAN_ERR_CRTL_TX_WARNING;
 537                         priv->can.state = CAN_STATE_ERROR_WARNING;
 538                         priv->can.can_stats.error_warning++;
 539                 }
 540         } else {
 541                 /* Back to error avtive */
 542                 cf->can_id |= CAN_ERR_PROT;
 543                 cf->data[2] = CAN_ERR_PROT_ACTIVE;
 544                 priv->can.state = CAN_STATE_ERROR_ACTIVE;
 545         }
 546 
 547         lec = status & STAT_LEC_MASK;
 548         if (lec < 7 && lec > 0) {
 549                 if (lec == STAT_LEC_ACK) {
 550                         cf->can_id |= CAN_ERR_ACK;
 551                 } else {
 552                         cf->can_id |= CAN_ERR_PROT;
 553                         switch (lec) {
 554                         case STAT_LEC_STUFF:
 555                                 cf->data[2] |= CAN_ERR_PROT_STUFF;
 556                                 break;
 557                         case STAT_LEC_FORM:
 558                                 cf->data[2] |= CAN_ERR_PROT_FORM;
 559                                 break;
 560                         case STAT_LEC_BIT1:
 561                                 cf->data[2] |= CAN_ERR_PROT_BIT1;
 562                                 break;
 563                         case STAT_LEC_BIT0:
 564                                 cf->data[2] |= CAN_ERR_PROT_BIT0;
 565                                 break;
 566                         case STAT_LEC_CRC:
 567                                 cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
 568                                 break;
 569                         }
 570                 }
 571         }
 572 
 573 
 574         stats->rx_packets++;
 575         stats->rx_bytes += cf->can_dlc;
 576         netif_rx(skb);
 577 
 578         return 0;
 579 }
 580 
 581 static int cc770_status_interrupt(struct net_device *dev)
 582 {
 583         struct cc770_priv *priv = netdev_priv(dev);
 584         u8 status;
 585 
 586         status = cc770_read_reg(priv, status);
 587         /* Reset the status register including RXOK and TXOK */
 588         cc770_write_reg(priv, status, STAT_LEC_MASK);
 589 
 590         if (status & (STAT_WARN | STAT_BOFF) ||
 591             (status & STAT_LEC_MASK) != STAT_LEC_MASK) {
 592                 cc770_err(dev, status);
 593                 return status & STAT_BOFF;
 594         }
 595 
 596         return 0;
 597 }
 598 
 599 static void cc770_rx_interrupt(struct net_device *dev, unsigned int o)
 600 {
 601         struct cc770_priv *priv = netdev_priv(dev);
 602         struct net_device_stats *stats = &dev->stats;
 603         unsigned int mo = obj2msgobj(o);
 604         u8 ctrl1;
 605         int n = CC770_MAX_MSG;
 606 
 607         while (n--) {
 608                 ctrl1 = cc770_read_reg(priv, msgobj[mo].ctrl1);
 609 
 610                 if (!(ctrl1 & NEWDAT_SET))  {
 611                         /* Check for RTR if additional functions are enabled */
 612                         if (priv->control_normal_mode & CTRL_EAF) {
 613                                 if (!(cc770_read_reg(priv, msgobj[mo].ctrl0) &
 614                                       INTPND_SET))
 615                                         break;
 616                         } else {
 617                                 break;
 618                         }
 619                 }
 620 
 621                 if (ctrl1 & MSGLST_SET) {
 622                         stats->rx_over_errors++;
 623                         stats->rx_errors++;
 624                 }
 625                 if (mo < MSGOBJ_LAST)
 626                         cc770_write_reg(priv, msgobj[mo].ctrl1,
 627                                         NEWDAT_RES | MSGLST_RES |
 628                                         TXRQST_UNC | RMTPND_UNC);
 629                 cc770_rx(dev, mo, ctrl1);
 630 
 631                 cc770_write_reg(priv, msgobj[mo].ctrl0,
 632                                 MSGVAL_SET | TXIE_RES |
 633                                 RXIE_SET | INTPND_RES);
 634                 cc770_write_reg(priv, msgobj[mo].ctrl1,
 635                                 NEWDAT_RES | MSGLST_RES |
 636                                 TXRQST_RES | RMTPND_RES);
 637         }
 638 }
 639 
 640 static void cc770_rtr_interrupt(struct net_device *dev, unsigned int o)
 641 {
 642         struct cc770_priv *priv = netdev_priv(dev);
 643         unsigned int mo = obj2msgobj(o);
 644         u8 ctrl0, ctrl1;
 645         int n = CC770_MAX_MSG;
 646 
 647         while (n--) {
 648                 ctrl0 = cc770_read_reg(priv, msgobj[mo].ctrl0);
 649                 if (!(ctrl0 & INTPND_SET))
 650                         break;
 651 
 652                 ctrl1 = cc770_read_reg(priv, msgobj[mo].ctrl1);
 653                 cc770_rx(dev, mo, ctrl1);
 654 
 655                 cc770_write_reg(priv, msgobj[mo].ctrl0,
 656                                 MSGVAL_SET | TXIE_RES |
 657                                 RXIE_SET | INTPND_RES);
 658                 cc770_write_reg(priv, msgobj[mo].ctrl1,
 659                                 NEWDAT_RES | CPUUPD_SET |
 660                                 TXRQST_RES | RMTPND_RES);
 661         }
 662 }
 663 
 664 static void cc770_tx_interrupt(struct net_device *dev, unsigned int o)
 665 {
 666         struct cc770_priv *priv = netdev_priv(dev);
 667         struct net_device_stats *stats = &dev->stats;
 668         unsigned int mo = obj2msgobj(o);
 669         struct can_frame *cf;
 670         u8 ctrl1;
 671 
 672         ctrl1 = cc770_read_reg(priv, msgobj[mo].ctrl1);
 673 
 674         cc770_write_reg(priv, msgobj[mo].ctrl0,
 675                         MSGVAL_RES | TXIE_RES | RXIE_RES | INTPND_RES);
 676         cc770_write_reg(priv, msgobj[mo].ctrl1,
 677                         RMTPND_RES | TXRQST_RES | MSGLST_RES | NEWDAT_RES);
 678 
 679         if (unlikely(!priv->tx_skb)) {
 680                 netdev_err(dev, "missing tx skb in tx interrupt\n");
 681                 return;
 682         }
 683 
 684         if (unlikely(ctrl1 & MSGLST_SET)) {
 685                 stats->rx_over_errors++;
 686                 stats->rx_errors++;
 687         }
 688 
 689         /* When the CC770 is sending an RTR message and it receives a regular
 690          * message that matches the id of the RTR message, it will overwrite the
 691          * outgoing message in the TX register. When this happens we must
 692          * process the received message and try to transmit the outgoing skb
 693          * again.
 694          */
 695         if (unlikely(ctrl1 & NEWDAT_SET)) {
 696                 cc770_rx(dev, mo, ctrl1);
 697                 cc770_tx(dev, mo);
 698                 return;
 699         }
 700 
 701         cf = (struct can_frame *)priv->tx_skb->data;
 702         stats->tx_bytes += cf->can_dlc;
 703         stats->tx_packets++;
 704 
 705         can_put_echo_skb(priv->tx_skb, dev, 0);
 706         can_get_echo_skb(dev, 0);
 707         priv->tx_skb = NULL;
 708 
 709         netif_wake_queue(dev);
 710 }
 711 
 712 static irqreturn_t cc770_interrupt(int irq, void *dev_id)
 713 {
 714         struct net_device *dev = (struct net_device *)dev_id;
 715         struct cc770_priv *priv = netdev_priv(dev);
 716         u8 intid;
 717         int o, n = 0;
 718 
 719         /* Shared interrupts and IRQ off? */
 720         if (priv->can.state == CAN_STATE_STOPPED)
 721                 return IRQ_NONE;
 722 
 723         if (priv->pre_irq)
 724                 priv->pre_irq(priv);
 725 
 726         while (n < CC770_MAX_IRQ) {
 727                 /* Read the highest pending interrupt request */
 728                 intid = cc770_read_reg(priv, interrupt);
 729                 if (!intid)
 730                         break;
 731                 n++;
 732 
 733                 if (intid == 1) {
 734                         /* Exit in case of bus-off */
 735                         if (cc770_status_interrupt(dev))
 736                                 break;
 737                 } else {
 738                         o = intid2obj(intid);
 739 
 740                         if (o >= CC770_OBJ_MAX) {
 741                                 netdev_err(dev, "Unexpected interrupt id %d\n",
 742                                            intid);
 743                                 continue;
 744                         }
 745 
 746                         if (priv->obj_flags[o] & CC770_OBJ_FLAG_RTR)
 747                                 cc770_rtr_interrupt(dev, o);
 748                         else if (priv->obj_flags[o] & CC770_OBJ_FLAG_RX)
 749                                 cc770_rx_interrupt(dev, o);
 750                         else
 751                                 cc770_tx_interrupt(dev, o);
 752                 }
 753         }
 754 
 755         if (priv->post_irq)
 756                 priv->post_irq(priv);
 757 
 758         if (n >= CC770_MAX_IRQ)
 759                 netdev_dbg(dev, "%d messages handled in ISR", n);
 760 
 761         return (n) ? IRQ_HANDLED : IRQ_NONE;
 762 }
 763 
 764 static int cc770_open(struct net_device *dev)
 765 {
 766         struct cc770_priv *priv = netdev_priv(dev);
 767         int err;
 768 
 769         /* set chip into reset mode */
 770         set_reset_mode(dev);
 771 
 772         /* common open */
 773         err = open_candev(dev);
 774         if (err)
 775                 return err;
 776 
 777         err = request_irq(dev->irq, &cc770_interrupt, priv->irq_flags,
 778                           dev->name, dev);
 779         if (err) {
 780                 close_candev(dev);
 781                 return -EAGAIN;
 782         }
 783 
 784         /* init and start chip */
 785         cc770_start(dev);
 786 
 787         netif_start_queue(dev);
 788 
 789         return 0;
 790 }
 791 
 792 static int cc770_close(struct net_device *dev)
 793 {
 794         netif_stop_queue(dev);
 795         set_reset_mode(dev);
 796 
 797         free_irq(dev->irq, dev);
 798         close_candev(dev);
 799 
 800         return 0;
 801 }
 802 
 803 struct net_device *alloc_cc770dev(int sizeof_priv)
 804 {
 805         struct net_device *dev;
 806         struct cc770_priv *priv;
 807 
 808         dev = alloc_candev(sizeof(struct cc770_priv) + sizeof_priv,
 809                            CC770_ECHO_SKB_MAX);
 810         if (!dev)
 811                 return NULL;
 812 
 813         priv = netdev_priv(dev);
 814 
 815         priv->dev = dev;
 816         priv->can.bittiming_const = &cc770_bittiming_const;
 817         priv->can.do_set_bittiming = cc770_set_bittiming;
 818         priv->can.do_set_mode = cc770_set_mode;
 819         priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
 820         priv->tx_skb = NULL;
 821 
 822         memcpy(priv->obj_flags, cc770_obj_flags, sizeof(cc770_obj_flags));
 823 
 824         if (sizeof_priv)
 825                 priv->priv = (void *)priv + sizeof(struct cc770_priv);
 826 
 827         return dev;
 828 }
 829 EXPORT_SYMBOL_GPL(alloc_cc770dev);
 830 
 831 void free_cc770dev(struct net_device *dev)
 832 {
 833         free_candev(dev);
 834 }
 835 EXPORT_SYMBOL_GPL(free_cc770dev);
 836 
 837 static const struct net_device_ops cc770_netdev_ops = {
 838         .ndo_open = cc770_open,
 839         .ndo_stop = cc770_close,
 840         .ndo_start_xmit = cc770_start_xmit,
 841         .ndo_change_mtu = can_change_mtu,
 842 };
 843 
 844 int register_cc770dev(struct net_device *dev)
 845 {
 846         struct cc770_priv *priv = netdev_priv(dev);
 847         int err;
 848 
 849         err = cc770_probe_chip(dev);
 850         if (err)
 851                 return err;
 852 
 853         dev->netdev_ops = &cc770_netdev_ops;
 854 
 855         dev->flags |= IFF_ECHO; /* we support local echo */
 856 
 857         /* Should we use additional functions? */
 858         if (!i82527_compat && priv->control_normal_mode & CTRL_EAF) {
 859                 priv->can.do_get_berr_counter = cc770_get_berr_counter;
 860                 priv->control_normal_mode = CTRL_IE | CTRL_EAF | CTRL_EIE;
 861                 netdev_dbg(dev, "i82527 mode with additional functions\n");
 862         } else {
 863                 priv->control_normal_mode = CTRL_IE | CTRL_EIE;
 864                 netdev_dbg(dev, "strict i82527 compatibility mode\n");
 865         }
 866 
 867         chipset_init(priv);
 868         set_reset_mode(dev);
 869 
 870         return register_candev(dev);
 871 }
 872 EXPORT_SYMBOL_GPL(register_cc770dev);
 873 
 874 void unregister_cc770dev(struct net_device *dev)
 875 {
 876         set_reset_mode(dev);
 877         unregister_candev(dev);
 878 }
 879 EXPORT_SYMBOL_GPL(unregister_cc770dev);
 880 
 881 static __init int cc770_init(void)
 882 {
 883         if (msgobj15_eff) {
 884                 cc770_obj_flags[CC770_OBJ_RX0] |= CC770_OBJ_FLAG_EFF;
 885                 cc770_obj_flags[CC770_OBJ_RX1] &= ~CC770_OBJ_FLAG_EFF;
 886         }
 887 
 888         pr_info("CAN netdevice driver\n");
 889 
 890         return 0;
 891 }
 892 module_init(cc770_init);
 893 
 894 static __exit void cc770_exit(void)
 895 {
 896         pr_info("driver removed\n");
 897 }
 898 module_exit(cc770_exit);
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/net/can/cc770/cc770.c

DEFINITIONS
