1 /* 2 * Au12x0/Au1550 PSC ALSA ASoC audio support. 3 * 4 * (c) 2007-2008 MSC Vertriebsges.m.b.H., 5 * Manuel Lauss <manuel.lauss@gmail.com> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * DMA glue for Au1x-PSC audio. 12 * 13 */ 14 15 16 #include <linux/module.h> 17 #include <linux/init.h> 18 #include <linux/platform_device.h> 19 #include <linux/slab.h> 20 #include <linux/dma-mapping.h> 21 22 #include <sound/core.h> 23 #include <sound/pcm.h> 24 #include <sound/pcm_params.h> 25 #include <sound/soc.h> 26 27 #include <asm/mach-au1x00/au1000.h> 28 #include <asm/mach-au1x00/au1xxx_dbdma.h> 29 #include <asm/mach-au1x00/au1xxx_psc.h> 30 31 #include "psc.h" 32 33 /*#define PCM_DEBUG*/ 34 35 #define DRV_NAME "dbdma2" 36 37 #define MSG(x...) printk(KERN_INFO "au1xpsc_pcm: " x) 38 #ifdef PCM_DEBUG 39 #define DBG MSG 40 #else 41 #define DBG(x...) do {} while (0) 42 #endif 43 44 struct au1xpsc_audio_dmadata { 45 /* DDMA control data */ 46 unsigned int ddma_id; /* DDMA direction ID for this PSC */ 47 u32 ddma_chan; /* DDMA context */ 48 49 /* PCM context (for irq handlers) */ 50 struct snd_pcm_substream *substream; 51 unsigned long curr_period; /* current segment DDMA is working on */ 52 unsigned long q_period; /* queue period(s) */ 53 dma_addr_t dma_area; /* address of queued DMA area */ 54 dma_addr_t dma_area_s; /* start address of DMA area */ 55 unsigned long pos; /* current byte position being played */ 56 unsigned long periods; /* number of SG segments in total */ 57 unsigned long period_bytes; /* size in bytes of one SG segment */ 58 59 /* runtime data */ 60 int msbits; 61 }; 62 63 /* 64 * These settings are somewhat okay, at least on my machine audio plays 65 * almost skip-free. Especially the 64kB buffer seems to help a LOT. 66 */ 67 #define AU1XPSC_PERIOD_MIN_BYTES 1024 68 #define AU1XPSC_BUFFER_MIN_BYTES 65536 69 70 /* PCM hardware DMA capabilities - platform specific */ 71 static const struct snd_pcm_hardware au1xpsc_pcm_hardware = { 72 .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID | 73 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BATCH, 74 .period_bytes_min = AU1XPSC_PERIOD_MIN_BYTES, 75 .period_bytes_max = 4096 * 1024 - 1, 76 .periods_min = 2, 77 .periods_max = 4096, /* 2 to as-much-as-you-like */ 78 .buffer_bytes_max = 4096 * 1024 - 1, 79 .fifo_size = 16, /* fifo entries of AC97/I2S PSC */ 80 }; 81 82 static void au1x_pcm_queue_tx(struct au1xpsc_audio_dmadata *cd) 83 { 84 au1xxx_dbdma_put_source(cd->ddma_chan, cd->dma_area, 85 cd->period_bytes, DDMA_FLAGS_IE); 86 87 /* update next-to-queue period */ 88 ++cd->q_period; 89 cd->dma_area += cd->period_bytes; 90 if (cd->q_period >= cd->periods) { 91 cd->q_period = 0; 92 cd->dma_area = cd->dma_area_s; 93 } 94 } 95 96 static void au1x_pcm_queue_rx(struct au1xpsc_audio_dmadata *cd) 97 { 98 au1xxx_dbdma_put_dest(cd->ddma_chan, cd->dma_area, 99 cd->period_bytes, DDMA_FLAGS_IE); 100 101 /* update next-to-queue period */ 102 ++cd->q_period; 103 cd->dma_area += cd->period_bytes; 104 if (cd->q_period >= cd->periods) { 105 cd->q_period = 0; 106 cd->dma_area = cd->dma_area_s; 107 } 108 } 109 110 static void au1x_pcm_dmatx_cb(int irq, void *dev_id) 111 { 112 struct au1xpsc_audio_dmadata *cd = dev_id; 113 114 cd->pos += cd->period_bytes; 115 if (++cd->curr_period >= cd->periods) { 116 cd->pos = 0; 117 cd->curr_period = 0; 118 } 119 snd_pcm_period_elapsed(cd->substream); 120 au1x_pcm_queue_tx(cd); 121 } 122 123 static void au1x_pcm_dmarx_cb(int irq, void *dev_id) 124 { 125 struct au1xpsc_audio_dmadata *cd = dev_id; 126 127 cd->pos += cd->period_bytes; 128 if (++cd->curr_period >= cd->periods) { 129 cd->pos = 0; 130 cd->curr_period = 0; 131 } 132 snd_pcm_period_elapsed(cd->substream); 133 au1x_pcm_queue_rx(cd); 134 } 135 136 static void au1x_pcm_dbdma_free(struct au1xpsc_audio_dmadata *pcd) 137 { 138 if (pcd->ddma_chan) { 139 au1xxx_dbdma_stop(pcd->ddma_chan); 140 au1xxx_dbdma_reset(pcd->ddma_chan); 141 au1xxx_dbdma_chan_free(pcd->ddma_chan); 142 pcd->ddma_chan = 0; 143 pcd->msbits = 0; 144 } 145 } 146 147 /* in case of missing DMA ring or changed TX-source / RX-dest bit widths, 148 * allocate (or reallocate) a 2-descriptor DMA ring with bit depth according 149 * to ALSA-supplied sample depth. This is due to limitations in the dbdma api 150 * (cannot adjust source/dest widths of already allocated descriptor ring). 151 */ 152 static int au1x_pcm_dbdma_realloc(struct au1xpsc_audio_dmadata *pcd, 153 int stype, int msbits) 154 { 155 /* DMA only in 8/16/32 bit widths */ 156 if (msbits == 24) 157 msbits = 32; 158 159 /* check current config: correct bits and descriptors allocated? */ 160 if ((pcd->ddma_chan) && (msbits == pcd->msbits)) 161 goto out; /* all ok! */ 162 163 au1x_pcm_dbdma_free(pcd); 164 165 if (stype == SNDRV_PCM_STREAM_CAPTURE) 166 pcd->ddma_chan = au1xxx_dbdma_chan_alloc(pcd->ddma_id, 167 DSCR_CMD0_ALWAYS, 168 au1x_pcm_dmarx_cb, (void *)pcd); 169 else 170 pcd->ddma_chan = au1xxx_dbdma_chan_alloc(DSCR_CMD0_ALWAYS, 171 pcd->ddma_id, 172 au1x_pcm_dmatx_cb, (void *)pcd); 173 174 if (!pcd->ddma_chan) 175 return -ENOMEM; 176 177 au1xxx_dbdma_set_devwidth(pcd->ddma_chan, msbits); 178 au1xxx_dbdma_ring_alloc(pcd->ddma_chan, 2); 179 180 pcd->msbits = msbits; 181 182 au1xxx_dbdma_stop(pcd->ddma_chan); 183 au1xxx_dbdma_reset(pcd->ddma_chan); 184 185 out: 186 return 0; 187 } 188 189 static inline struct au1xpsc_audio_dmadata *to_dmadata(struct snd_pcm_substream *ss) 190 { 191 struct snd_soc_pcm_runtime *rtd = ss->private_data; 192 struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd, DRV_NAME); 193 struct au1xpsc_audio_dmadata *pcd = snd_soc_component_get_drvdata(component); 194 return &pcd[ss->stream]; 195 } 196 197 static int au1xpsc_pcm_hw_params(struct snd_pcm_substream *substream, 198 struct snd_pcm_hw_params *params) 199 { 200 struct snd_pcm_runtime *runtime = substream->runtime; 201 struct au1xpsc_audio_dmadata *pcd; 202 int stype, ret; 203 204 ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params)); 205 if (ret < 0) 206 goto out; 207 208 stype = substream->stream; 209 pcd = to_dmadata(substream); 210 211 DBG("runtime->dma_area = 0x%08lx dma_addr_t = 0x%08lx dma_size = %zu " 212 "runtime->min_align %lu\n", 213 (unsigned long)runtime->dma_area, 214 (unsigned long)runtime->dma_addr, runtime->dma_bytes, 215 runtime->min_align); 216 217 DBG("bits %d frags %d frag_bytes %d is_rx %d\n", params->msbits, 218 params_periods(params), params_period_bytes(params), stype); 219 220 ret = au1x_pcm_dbdma_realloc(pcd, stype, params->msbits); 221 if (ret) { 222 MSG("DDMA channel (re)alloc failed!\n"); 223 goto out; 224 } 225 226 pcd->substream = substream; 227 pcd->period_bytes = params_period_bytes(params); 228 pcd->periods = params_periods(params); 229 pcd->dma_area_s = pcd->dma_area = runtime->dma_addr; 230 pcd->q_period = 0; 231 pcd->curr_period = 0; 232 pcd->pos = 0; 233 234 ret = 0; 235 out: 236 return ret; 237 } 238 239 static int au1xpsc_pcm_hw_free(struct snd_pcm_substream *substream) 240 { 241 snd_pcm_lib_free_pages(substream); 242 return 0; 243 } 244 245 static int au1xpsc_pcm_prepare(struct snd_pcm_substream *substream) 246 { 247 struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream); 248 249 au1xxx_dbdma_reset(pcd->ddma_chan); 250 251 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) { 252 au1x_pcm_queue_rx(pcd); 253 au1x_pcm_queue_rx(pcd); 254 } else { 255 au1x_pcm_queue_tx(pcd); 256 au1x_pcm_queue_tx(pcd); 257 } 258 259 return 0; 260 } 261 262 static int au1xpsc_pcm_trigger(struct snd_pcm_substream *substream, int cmd) 263 { 264 u32 c = to_dmadata(substream)->ddma_chan; 265 266 switch (cmd) { 267 case SNDRV_PCM_TRIGGER_START: 268 case SNDRV_PCM_TRIGGER_RESUME: 269 au1xxx_dbdma_start(c); 270 break; 271 case SNDRV_PCM_TRIGGER_STOP: 272 case SNDRV_PCM_TRIGGER_SUSPEND: 273 au1xxx_dbdma_stop(c); 274 break; 275 default: 276 return -EINVAL; 277 } 278 return 0; 279 } 280 281 static snd_pcm_uframes_t 282 au1xpsc_pcm_pointer(struct snd_pcm_substream *substream) 283 { 284 return bytes_to_frames(substream->runtime, to_dmadata(substream)->pos); 285 } 286 287 static int au1xpsc_pcm_open(struct snd_pcm_substream *substream) 288 { 289 struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream); 290 struct snd_soc_pcm_runtime *rtd = substream->private_data; 291 int stype = substream->stream, *dmaids; 292 293 dmaids = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); 294 if (!dmaids) 295 return -ENODEV; /* whoa, has ordering changed? */ 296 297 pcd->ddma_id = dmaids[stype]; 298 299 snd_soc_set_runtime_hwparams(substream, &au1xpsc_pcm_hardware); 300 return 0; 301 } 302 303 static int au1xpsc_pcm_close(struct snd_pcm_substream *substream) 304 { 305 au1x_pcm_dbdma_free(to_dmadata(substream)); 306 return 0; 307 } 308 309 static const struct snd_pcm_ops au1xpsc_pcm_ops = { 310 .open = au1xpsc_pcm_open, 311 .close = au1xpsc_pcm_close, 312 .ioctl = snd_pcm_lib_ioctl, 313 .hw_params = au1xpsc_pcm_hw_params, 314 .hw_free = au1xpsc_pcm_hw_free, 315 .prepare = au1xpsc_pcm_prepare, 316 .trigger = au1xpsc_pcm_trigger, 317 .pointer = au1xpsc_pcm_pointer, 318 }; 319 320 static int au1xpsc_pcm_new(struct snd_soc_pcm_runtime *rtd) 321 { 322 struct snd_card *card = rtd->card->snd_card; 323 struct snd_pcm *pcm = rtd->pcm; 324 325 snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV, 326 card->dev, AU1XPSC_BUFFER_MIN_BYTES, (4096 * 1024) - 1); 327 328 return 0; 329 } 330 331 /* au1xpsc audio platform */ 332 static struct snd_soc_component_driver au1xpsc_soc_component = { 333 .name = DRV_NAME, 334 .ops = &au1xpsc_pcm_ops, 335 .pcm_new = au1xpsc_pcm_new, 336 }; 337 338 static int au1xpsc_pcm_drvprobe(struct platform_device *pdev) 339 { 340 struct au1xpsc_audio_dmadata *dmadata; 341 342 dmadata = devm_kzalloc(&pdev->dev, 343 2 * sizeof(struct au1xpsc_audio_dmadata), 344 GFP_KERNEL); 345 if (!dmadata) 346 return -ENOMEM; 347 348 platform_set_drvdata(pdev, dmadata); 349 350 return devm_snd_soc_register_component(&pdev->dev, 351 &au1xpsc_soc_component, NULL, 0); 352 } 353 354 static struct platform_driver au1xpsc_pcm_driver = { 355 .driver = { 356 .name = "au1xpsc-pcm", 357 }, 358 .probe = au1xpsc_pcm_drvprobe, 359 }; 360 361 module_platform_driver(au1xpsc_pcm_driver); 362 363 MODULE_LICENSE("GPL"); 364 MODULE_DESCRIPTION("Au12x0/Au1550 PSC Audio DMA driver"); 365 MODULE_AUTHOR("Manuel Lauss"); 366