1/* 2 * kirkwood-dma.c 3 * 4 * (c) 2010 Arnaud Patard <apatard@mandriva.com> 5 * (c) 2010 Arnaud Patard <arnaud.patard@rtp-net.org> 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License as published by the 9 * Free Software Foundation; either version 2 of the License, or (at your 10 * option) any later version. 11 */ 12 13#include <linux/init.h> 14#include <linux/module.h> 15#include <linux/device.h> 16#include <linux/io.h> 17#include <linux/slab.h> 18#include <linux/interrupt.h> 19#include <linux/dma-mapping.h> 20#include <linux/mbus.h> 21#include <sound/soc.h> 22#include "kirkwood.h" 23 24static struct kirkwood_dma_data *kirkwood_priv(struct snd_pcm_substream *subs) 25{ 26 struct snd_soc_pcm_runtime *soc_runtime = subs->private_data; 27 return snd_soc_dai_get_drvdata(soc_runtime->cpu_dai); 28} 29 30static struct snd_pcm_hardware kirkwood_dma_snd_hw = { 31 .info = SNDRV_PCM_INFO_INTERLEAVED | 32 SNDRV_PCM_INFO_MMAP | 33 SNDRV_PCM_INFO_MMAP_VALID | 34 SNDRV_PCM_INFO_BLOCK_TRANSFER | 35 SNDRV_PCM_INFO_PAUSE | 36 SNDRV_PCM_INFO_NO_PERIOD_WAKEUP, 37 .buffer_bytes_max = KIRKWOOD_SND_MAX_BUFFER_BYTES, 38 .period_bytes_min = KIRKWOOD_SND_MIN_PERIOD_BYTES, 39 .period_bytes_max = KIRKWOOD_SND_MAX_PERIOD_BYTES, 40 .periods_min = KIRKWOOD_SND_MIN_PERIODS, 41 .periods_max = KIRKWOOD_SND_MAX_PERIODS, 42 .fifo_size = 0, 43}; 44 45static irqreturn_t kirkwood_dma_irq(int irq, void *dev_id) 46{ 47 struct kirkwood_dma_data *priv = dev_id; 48 unsigned long mask, status, cause; 49 50 mask = readl(priv->io + KIRKWOOD_INT_MASK); 51 status = readl(priv->io + KIRKWOOD_INT_CAUSE) & mask; 52 53 cause = readl(priv->io + KIRKWOOD_ERR_CAUSE); 54 if (unlikely(cause)) { 55 printk(KERN_WARNING "%s: got err interrupt 0x%lx\n", 56 __func__, cause); 57 writel(cause, priv->io + KIRKWOOD_ERR_CAUSE); 58 } 59 60 /* we've enabled only bytes interrupts ... */ 61 if (status & ~(KIRKWOOD_INT_CAUSE_PLAY_BYTES | \ 62 KIRKWOOD_INT_CAUSE_REC_BYTES)) { 63 printk(KERN_WARNING "%s: unexpected interrupt %lx\n", 64 __func__, status); 65 return IRQ_NONE; 66 } 67 68 /* ack int */ 69 writel(status, priv->io + KIRKWOOD_INT_CAUSE); 70 71 if (status & KIRKWOOD_INT_CAUSE_PLAY_BYTES) 72 snd_pcm_period_elapsed(priv->substream_play); 73 74 if (status & KIRKWOOD_INT_CAUSE_REC_BYTES) 75 snd_pcm_period_elapsed(priv->substream_rec); 76 77 return IRQ_HANDLED; 78} 79 80static void 81kirkwood_dma_conf_mbus_windows(void __iomem *base, int win, 82 unsigned long dma, 83 const struct mbus_dram_target_info *dram) 84{ 85 int i; 86 87 /* First disable and clear windows */ 88 writel(0, base + KIRKWOOD_AUDIO_WIN_CTRL_REG(win)); 89 writel(0, base + KIRKWOOD_AUDIO_WIN_BASE_REG(win)); 90 91 /* try to find matching cs for current dma address */ 92 for (i = 0; i < dram->num_cs; i++) { 93 const struct mbus_dram_window *cs = dram->cs + i; 94 if ((cs->base & 0xffff0000) < (dma & 0xffff0000)) { 95 writel(cs->base & 0xffff0000, 96 base + KIRKWOOD_AUDIO_WIN_BASE_REG(win)); 97 writel(((cs->size - 1) & 0xffff0000) | 98 (cs->mbus_attr << 8) | 99 (dram->mbus_dram_target_id << 4) | 1, 100 base + KIRKWOOD_AUDIO_WIN_CTRL_REG(win)); 101 } 102 } 103} 104 105static int kirkwood_dma_open(struct snd_pcm_substream *substream) 106{ 107 int err; 108 struct snd_pcm_runtime *runtime = substream->runtime; 109 struct kirkwood_dma_data *priv = kirkwood_priv(substream); 110 const struct mbus_dram_target_info *dram; 111 unsigned long addr; 112 113 snd_soc_set_runtime_hwparams(substream, &kirkwood_dma_snd_hw); 114 115 /* Ensure that all constraints linked to dma burst are fulfilled */ 116 err = snd_pcm_hw_constraint_minmax(runtime, 117 SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 118 priv->burst * 2, 119 KIRKWOOD_AUDIO_BUF_MAX-1); 120 if (err < 0) 121 return err; 122 123 err = snd_pcm_hw_constraint_step(runtime, 0, 124 SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 125 priv->burst); 126 if (err < 0) 127 return err; 128 129 err = snd_pcm_hw_constraint_step(substream->runtime, 0, 130 SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 131 priv->burst); 132 if (err < 0) 133 return err; 134 135 if (!priv->substream_play && !priv->substream_rec) { 136 err = request_irq(priv->irq, kirkwood_dma_irq, IRQF_SHARED, 137 "kirkwood-i2s", priv); 138 if (err) 139 return -EBUSY; 140 141 /* 142 * Enable Error interrupts. We're only ack'ing them but 143 * it's useful for diagnostics 144 */ 145 writel((unsigned int)-1, priv->io + KIRKWOOD_ERR_MASK); 146 } 147 148 dram = mv_mbus_dram_info(); 149 addr = substream->dma_buffer.addr; 150 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { 151 priv->substream_play = substream; 152 kirkwood_dma_conf_mbus_windows(priv->io, 153 KIRKWOOD_PLAYBACK_WIN, addr, dram); 154 } else { 155 priv->substream_rec = substream; 156 kirkwood_dma_conf_mbus_windows(priv->io, 157 KIRKWOOD_RECORD_WIN, addr, dram); 158 } 159 160 return 0; 161} 162 163static int kirkwood_dma_close(struct snd_pcm_substream *substream) 164{ 165 struct kirkwood_dma_data *priv = kirkwood_priv(substream); 166 167 if (!priv) 168 return 0; 169 170 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) 171 priv->substream_play = NULL; 172 else 173 priv->substream_rec = NULL; 174 175 if (!priv->substream_play && !priv->substream_rec) { 176 writel(0, priv->io + KIRKWOOD_ERR_MASK); 177 free_irq(priv->irq, priv); 178 } 179 180 return 0; 181} 182 183static int kirkwood_dma_hw_params(struct snd_pcm_substream *substream, 184 struct snd_pcm_hw_params *params) 185{ 186 struct snd_pcm_runtime *runtime = substream->runtime; 187 188 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); 189 runtime->dma_bytes = params_buffer_bytes(params); 190 191 return 0; 192} 193 194static int kirkwood_dma_hw_free(struct snd_pcm_substream *substream) 195{ 196 snd_pcm_set_runtime_buffer(substream, NULL); 197 return 0; 198} 199 200static int kirkwood_dma_prepare(struct snd_pcm_substream *substream) 201{ 202 struct snd_pcm_runtime *runtime = substream->runtime; 203 struct kirkwood_dma_data *priv = kirkwood_priv(substream); 204 unsigned long size, count; 205 206 /* compute buffer size in term of "words" as requested in specs */ 207 size = frames_to_bytes(runtime, runtime->buffer_size); 208 size = (size>>2)-1; 209 count = snd_pcm_lib_period_bytes(substream); 210 211 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { 212 writel(count, priv->io + KIRKWOOD_PLAY_BYTE_INT_COUNT); 213 writel(runtime->dma_addr, priv->io + KIRKWOOD_PLAY_BUF_ADDR); 214 writel(size, priv->io + KIRKWOOD_PLAY_BUF_SIZE); 215 } else { 216 writel(count, priv->io + KIRKWOOD_REC_BYTE_INT_COUNT); 217 writel(runtime->dma_addr, priv->io + KIRKWOOD_REC_BUF_ADDR); 218 writel(size, priv->io + KIRKWOOD_REC_BUF_SIZE); 219 } 220 221 222 return 0; 223} 224 225static snd_pcm_uframes_t kirkwood_dma_pointer(struct snd_pcm_substream 226 *substream) 227{ 228 struct kirkwood_dma_data *priv = kirkwood_priv(substream); 229 snd_pcm_uframes_t count; 230 231 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) 232 count = bytes_to_frames(substream->runtime, 233 readl(priv->io + KIRKWOOD_PLAY_BYTE_COUNT)); 234 else 235 count = bytes_to_frames(substream->runtime, 236 readl(priv->io + KIRKWOOD_REC_BYTE_COUNT)); 237 238 return count; 239} 240 241static struct snd_pcm_ops kirkwood_dma_ops = { 242 .open = kirkwood_dma_open, 243 .close = kirkwood_dma_close, 244 .ioctl = snd_pcm_lib_ioctl, 245 .hw_params = kirkwood_dma_hw_params, 246 .hw_free = kirkwood_dma_hw_free, 247 .prepare = kirkwood_dma_prepare, 248 .pointer = kirkwood_dma_pointer, 249}; 250 251static int kirkwood_dma_preallocate_dma_buffer(struct snd_pcm *pcm, 252 int stream) 253{ 254 struct snd_pcm_substream *substream = pcm->streams[stream].substream; 255 struct snd_dma_buffer *buf = &substream->dma_buffer; 256 size_t size = kirkwood_dma_snd_hw.buffer_bytes_max; 257 258 buf->dev.type = SNDRV_DMA_TYPE_DEV; 259 buf->dev.dev = pcm->card->dev; 260 buf->area = dma_alloc_coherent(pcm->card->dev, size, 261 &buf->addr, GFP_KERNEL); 262 if (!buf->area) 263 return -ENOMEM; 264 buf->bytes = size; 265 buf->private_data = NULL; 266 267 return 0; 268} 269 270static int kirkwood_dma_new(struct snd_soc_pcm_runtime *rtd) 271{ 272 struct snd_card *card = rtd->card->snd_card; 273 struct snd_pcm *pcm = rtd->pcm; 274 int ret; 275 276 ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32)); 277 if (ret) 278 return ret; 279 280 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) { 281 ret = kirkwood_dma_preallocate_dma_buffer(pcm, 282 SNDRV_PCM_STREAM_PLAYBACK); 283 if (ret) 284 return ret; 285 } 286 287 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) { 288 ret = kirkwood_dma_preallocate_dma_buffer(pcm, 289 SNDRV_PCM_STREAM_CAPTURE); 290 if (ret) 291 return ret; 292 } 293 294 return 0; 295} 296 297static void kirkwood_dma_free_dma_buffers(struct snd_pcm *pcm) 298{ 299 struct snd_pcm_substream *substream; 300 struct snd_dma_buffer *buf; 301 int stream; 302 303 for (stream = 0; stream < 2; stream++) { 304 substream = pcm->streams[stream].substream; 305 if (!substream) 306 continue; 307 buf = &substream->dma_buffer; 308 if (!buf->area) 309 continue; 310 311 dma_free_coherent(pcm->card->dev, buf->bytes, 312 buf->area, buf->addr); 313 buf->area = NULL; 314 } 315} 316 317struct snd_soc_platform_driver kirkwood_soc_platform = { 318 .ops = &kirkwood_dma_ops, 319 .pcm_new = kirkwood_dma_new, 320 .pcm_free = kirkwood_dma_free_dma_buffers, 321}; 322