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 24 static 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 30 static 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 45 static 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 80 static void 81 kirkwood_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 } 104 105 static 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 if (priv->substream_play) 152 return -EBUSY; 153 priv->substream_play = substream; 154 kirkwood_dma_conf_mbus_windows(priv->io, 155 KIRKWOOD_PLAYBACK_WIN, addr, dram); 156 } else { 157 if (priv->substream_rec) 158 return -EBUSY; 159 priv->substream_rec = substream; 160 kirkwood_dma_conf_mbus_windows(priv->io, 161 KIRKWOOD_RECORD_WIN, addr, dram); 162 } 163 164 return 0; 165 } 166 167 static int kirkwood_dma_close(struct snd_pcm_substream *substream) 168 { 169 struct kirkwood_dma_data *priv = kirkwood_priv(substream); 170 171 if (!priv) 172 return 0; 173 174 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) 175 priv->substream_play = NULL; 176 else 177 priv->substream_rec = NULL; 178 179 if (!priv->substream_play && !priv->substream_rec) { 180 writel(0, priv->io + KIRKWOOD_ERR_MASK); 181 free_irq(priv->irq, priv); 182 } 183 184 return 0; 185 } 186 187 static int kirkwood_dma_hw_params(struct snd_pcm_substream *substream, 188 struct snd_pcm_hw_params *params) 189 { 190 struct snd_pcm_runtime *runtime = substream->runtime; 191 192 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); 193 runtime->dma_bytes = params_buffer_bytes(params); 194 195 return 0; 196 } 197 198 static int kirkwood_dma_hw_free(struct snd_pcm_substream *substream) 199 { 200 snd_pcm_set_runtime_buffer(substream, NULL); 201 return 0; 202 } 203 204 static int kirkwood_dma_prepare(struct snd_pcm_substream *substream) 205 { 206 struct snd_pcm_runtime *runtime = substream->runtime; 207 struct kirkwood_dma_data *priv = kirkwood_priv(substream); 208 unsigned long size, count; 209 210 /* compute buffer size in term of "words" as requested in specs */ 211 size = frames_to_bytes(runtime, runtime->buffer_size); 212 size = (size>>2)-1; 213 count = snd_pcm_lib_period_bytes(substream); 214 215 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { 216 writel(count, priv->io + KIRKWOOD_PLAY_BYTE_INT_COUNT); 217 writel(runtime->dma_addr, priv->io + KIRKWOOD_PLAY_BUF_ADDR); 218 writel(size, priv->io + KIRKWOOD_PLAY_BUF_SIZE); 219 } else { 220 writel(count, priv->io + KIRKWOOD_REC_BYTE_INT_COUNT); 221 writel(runtime->dma_addr, priv->io + KIRKWOOD_REC_BUF_ADDR); 222 writel(size, priv->io + KIRKWOOD_REC_BUF_SIZE); 223 } 224 225 226 return 0; 227 } 228 229 static snd_pcm_uframes_t kirkwood_dma_pointer(struct snd_pcm_substream 230 *substream) 231 { 232 struct kirkwood_dma_data *priv = kirkwood_priv(substream); 233 snd_pcm_uframes_t count; 234 235 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) 236 count = bytes_to_frames(substream->runtime, 237 readl(priv->io + KIRKWOOD_PLAY_BYTE_COUNT)); 238 else 239 count = bytes_to_frames(substream->runtime, 240 readl(priv->io + KIRKWOOD_REC_BYTE_COUNT)); 241 242 return count; 243 } 244 245 static struct snd_pcm_ops kirkwood_dma_ops = { 246 .open = kirkwood_dma_open, 247 .close = kirkwood_dma_close, 248 .ioctl = snd_pcm_lib_ioctl, 249 .hw_params = kirkwood_dma_hw_params, 250 .hw_free = kirkwood_dma_hw_free, 251 .prepare = kirkwood_dma_prepare, 252 .pointer = kirkwood_dma_pointer, 253 }; 254 255 static int kirkwood_dma_preallocate_dma_buffer(struct snd_pcm *pcm, 256 int stream) 257 { 258 struct snd_pcm_substream *substream = pcm->streams[stream].substream; 259 struct snd_dma_buffer *buf = &substream->dma_buffer; 260 size_t size = kirkwood_dma_snd_hw.buffer_bytes_max; 261 262 buf->dev.type = SNDRV_DMA_TYPE_DEV; 263 buf->dev.dev = pcm->card->dev; 264 buf->area = dma_alloc_coherent(pcm->card->dev, size, 265 &buf->addr, GFP_KERNEL); 266 if (!buf->area) 267 return -ENOMEM; 268 buf->bytes = size; 269 buf->private_data = NULL; 270 271 return 0; 272 } 273 274 static int kirkwood_dma_new(struct snd_soc_pcm_runtime *rtd) 275 { 276 struct snd_card *card = rtd->card->snd_card; 277 struct snd_pcm *pcm = rtd->pcm; 278 int ret; 279 280 ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32)); 281 if (ret) 282 return ret; 283 284 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) { 285 ret = kirkwood_dma_preallocate_dma_buffer(pcm, 286 SNDRV_PCM_STREAM_PLAYBACK); 287 if (ret) 288 return ret; 289 } 290 291 if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) { 292 ret = kirkwood_dma_preallocate_dma_buffer(pcm, 293 SNDRV_PCM_STREAM_CAPTURE); 294 if (ret) 295 return ret; 296 } 297 298 return 0; 299 } 300 301 static void kirkwood_dma_free_dma_buffers(struct snd_pcm *pcm) 302 { 303 struct snd_pcm_substream *substream; 304 struct snd_dma_buffer *buf; 305 int stream; 306 307 for (stream = 0; stream < 2; stream++) { 308 substream = pcm->streams[stream].substream; 309 if (!substream) 310 continue; 311 buf = &substream->dma_buffer; 312 if (!buf->area) 313 continue; 314 315 dma_free_coherent(pcm->card->dev, buf->bytes, 316 buf->area, buf->addr); 317 buf->area = NULL; 318 } 319 } 320 321 struct snd_soc_platform_driver kirkwood_soc_platform = { 322 .ops = &kirkwood_dma_ops, 323 .pcm_new = kirkwood_dma_new, 324 .pcm_free = kirkwood_dma_free_dma_buffers, 325 }; 326