1 /* 2 * sound/soc/samsung/idma.c 3 * 4 * Copyright (c) 2011 Samsung Electronics Co., Ltd. 5 * http://www.samsung.com 6 * 7 * I2S0's Internal DMA driver 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms of the GNU General Public License as published by the 11 * Free Software Foundation; either version 2 of the License, or (at your 12 * option) any later version. 13 */ 14 #include <linux/interrupt.h> 15 #include <linux/platform_device.h> 16 #include <linux/dma-mapping.h> 17 #include <linux/slab.h> 18 #include <linux/module.h> 19 #include <sound/pcm.h> 20 #include <sound/pcm_params.h> 21 #include <sound/soc.h> 22 23 #include "i2s.h" 24 #include "idma.h" 25 #include "dma.h" 26 #include "i2s-regs.h" 27 28 #define ST_RUNNING (1<<0) 29 #define ST_OPENED (1<<1) 30 31 static const struct snd_pcm_hardware idma_hardware = { 32 .info = SNDRV_PCM_INFO_INTERLEAVED | 33 SNDRV_PCM_INFO_BLOCK_TRANSFER | 34 SNDRV_PCM_INFO_MMAP | 35 SNDRV_PCM_INFO_MMAP_VALID | 36 SNDRV_PCM_INFO_PAUSE | 37 SNDRV_PCM_INFO_RESUME, 38 .buffer_bytes_max = MAX_IDMA_BUFFER, 39 .period_bytes_min = 128, 40 .period_bytes_max = MAX_IDMA_PERIOD, 41 .periods_min = 1, 42 .periods_max = 2, 43 }; 44 45 struct idma_ctrl { 46 spinlock_t lock; 47 int state; 48 dma_addr_t start; 49 dma_addr_t pos; 50 dma_addr_t end; 51 dma_addr_t period; 52 dma_addr_t periodsz; 53 void *token; 54 void (*cb)(void *dt, int bytes_xfer); 55 }; 56 57 static struct idma_info { 58 spinlock_t lock; 59 void __iomem *regs; 60 dma_addr_t lp_tx_addr; 61 } idma; 62 63 static int idma_irq; 64 65 static void idma_getpos(dma_addr_t *src) 66 { 67 *src = idma.lp_tx_addr + 68 (readl(idma.regs + I2STRNCNT) & 0xffffff) * 4; 69 } 70 71 static int idma_enqueue(struct snd_pcm_substream *substream) 72 { 73 struct snd_pcm_runtime *runtime = substream->runtime; 74 struct idma_ctrl *prtd = substream->runtime->private_data; 75 u32 val; 76 77 spin_lock(&prtd->lock); 78 prtd->token = (void *) substream; 79 spin_unlock(&prtd->lock); 80 81 /* Internal DMA Level0 Interrupt Address */ 82 val = idma.lp_tx_addr + prtd->periodsz; 83 writel(val, idma.regs + I2SLVL0ADDR); 84 85 /* Start address0 of I2S internal DMA operation. */ 86 val = idma.lp_tx_addr; 87 writel(val, idma.regs + I2SSTR0); 88 89 /* 90 * Transfer block size for I2S internal DMA. 91 * Should decide transfer size before start dma operation 92 */ 93 val = readl(idma.regs + I2SSIZE); 94 val &= ~(I2SSIZE_TRNMSK << I2SSIZE_SHIFT); 95 val |= (((runtime->dma_bytes >> 2) & 96 I2SSIZE_TRNMSK) << I2SSIZE_SHIFT); 97 writel(val, idma.regs + I2SSIZE); 98 99 val = readl(idma.regs + I2SAHB); 100 val |= AHB_INTENLVL0; 101 writel(val, idma.regs + I2SAHB); 102 103 return 0; 104 } 105 106 static void idma_setcallbk(struct snd_pcm_substream *substream, 107 void (*cb)(void *, int)) 108 { 109 struct idma_ctrl *prtd = substream->runtime->private_data; 110 111 spin_lock(&prtd->lock); 112 prtd->cb = cb; 113 spin_unlock(&prtd->lock); 114 } 115 116 static void idma_control(int op) 117 { 118 u32 val = readl(idma.regs + I2SAHB); 119 120 spin_lock(&idma.lock); 121 122 switch (op) { 123 case LPAM_DMA_START: 124 val |= (AHB_INTENLVL0 | AHB_DMAEN); 125 break; 126 case LPAM_DMA_STOP: 127 val &= ~(AHB_INTENLVL0 | AHB_DMAEN); 128 break; 129 default: 130 spin_unlock(&idma.lock); 131 return; 132 } 133 134 writel(val, idma.regs + I2SAHB); 135 spin_unlock(&idma.lock); 136 } 137 138 static void idma_done(void *id, int bytes_xfer) 139 { 140 struct snd_pcm_substream *substream = id; 141 struct idma_ctrl *prtd = substream->runtime->private_data; 142 143 if (prtd && (prtd->state & ST_RUNNING)) 144 snd_pcm_period_elapsed(substream); 145 } 146 147 static int idma_hw_params(struct snd_pcm_substream *substream, 148 struct snd_pcm_hw_params *params) 149 { 150 struct snd_pcm_runtime *runtime = substream->runtime; 151 struct idma_ctrl *prtd = substream->runtime->private_data; 152 u32 mod = readl(idma.regs + I2SMOD); 153 u32 ahb = readl(idma.regs + I2SAHB); 154 155 ahb |= (AHB_DMARLD | AHB_INTMASK); 156 mod |= MOD_TXS_IDMA; 157 writel(ahb, idma.regs + I2SAHB); 158 writel(mod, idma.regs + I2SMOD); 159 160 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); 161 runtime->dma_bytes = params_buffer_bytes(params); 162 163 prtd->start = prtd->pos = runtime->dma_addr; 164 prtd->period = params_periods(params); 165 prtd->periodsz = params_period_bytes(params); 166 prtd->end = runtime->dma_addr + runtime->dma_bytes; 167 168 idma_setcallbk(substream, idma_done); 169 170 return 0; 171 } 172 173 static int idma_hw_free(struct snd_pcm_substream *substream) 174 { 175 snd_pcm_set_runtime_buffer(substream, NULL); 176 177 return 0; 178 } 179 180 static int idma_prepare(struct snd_pcm_substream *substream) 181 { 182 struct idma_ctrl *prtd = substream->runtime->private_data; 183 184 prtd->pos = prtd->start; 185 186 /* flush the DMA channel */ 187 idma_control(LPAM_DMA_STOP); 188 idma_enqueue(substream); 189 190 return 0; 191 } 192 193 static int idma_trigger(struct snd_pcm_substream *substream, int cmd) 194 { 195 struct idma_ctrl *prtd = substream->runtime->private_data; 196 int ret = 0; 197 198 spin_lock(&prtd->lock); 199 200 switch (cmd) { 201 case SNDRV_PCM_TRIGGER_RESUME: 202 case SNDRV_PCM_TRIGGER_START: 203 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: 204 prtd->state |= ST_RUNNING; 205 idma_control(LPAM_DMA_START); 206 break; 207 208 case SNDRV_PCM_TRIGGER_SUSPEND: 209 case SNDRV_PCM_TRIGGER_STOP: 210 case SNDRV_PCM_TRIGGER_PAUSE_PUSH: 211 prtd->state &= ~ST_RUNNING; 212 idma_control(LPAM_DMA_STOP); 213 break; 214 215 default: 216 ret = -EINVAL; 217 break; 218 } 219 220 spin_unlock(&prtd->lock); 221 222 return ret; 223 } 224 225 static snd_pcm_uframes_t 226 idma_pointer(struct snd_pcm_substream *substream) 227 { 228 struct snd_pcm_runtime *runtime = substream->runtime; 229 struct idma_ctrl *prtd = runtime->private_data; 230 dma_addr_t src; 231 unsigned long res; 232 233 spin_lock(&prtd->lock); 234 235 idma_getpos(&src); 236 res = src - prtd->start; 237 238 spin_unlock(&prtd->lock); 239 240 return bytes_to_frames(substream->runtime, res); 241 } 242 243 static int idma_mmap(struct snd_pcm_substream *substream, 244 struct vm_area_struct *vma) 245 { 246 struct snd_pcm_runtime *runtime = substream->runtime; 247 unsigned long size, offset; 248 int ret; 249 250 /* From snd_pcm_lib_mmap_iomem */ 251 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); 252 size = vma->vm_end - vma->vm_start; 253 offset = vma->vm_pgoff << PAGE_SHIFT; 254 ret = io_remap_pfn_range(vma, vma->vm_start, 255 (runtime->dma_addr + offset) >> PAGE_SHIFT, 256 size, vma->vm_page_prot); 257 258 return ret; 259 } 260 261 static irqreturn_t iis_irq(int irqno, void *dev_id) 262 { 263 struct idma_ctrl *prtd = (struct idma_ctrl *)dev_id; 264 u32 iisahb, val, addr; 265 266 iisahb = readl(idma.regs + I2SAHB); 267 268 val = (iisahb & AHB_LVL0INT) ? AHB_CLRLVL0INT : 0; 269 270 if (val) { 271 iisahb |= val; 272 writel(iisahb, idma.regs + I2SAHB); 273 274 addr = readl(idma.regs + I2SLVL0ADDR) - idma.lp_tx_addr; 275 addr += prtd->periodsz; 276 addr %= (u32)(prtd->end - prtd->start); 277 addr += idma.lp_tx_addr; 278 279 writel(addr, idma.regs + I2SLVL0ADDR); 280 281 if (prtd->cb) 282 prtd->cb(prtd->token, prtd->period); 283 } 284 285 return IRQ_HANDLED; 286 } 287 288 static int idma_open(struct snd_pcm_substream *substream) 289 { 290 struct snd_pcm_runtime *runtime = substream->runtime; 291 struct idma_ctrl *prtd; 292 int ret; 293 294 snd_soc_set_runtime_hwparams(substream, &idma_hardware); 295 296 prtd = kzalloc(sizeof(struct idma_ctrl), GFP_KERNEL); 297 if (prtd == NULL) 298 return -ENOMEM; 299 300 ret = request_irq(idma_irq, iis_irq, 0, "i2s", prtd); 301 if (ret < 0) { 302 pr_err("fail to claim i2s irq , ret = %d\n", ret); 303 kfree(prtd); 304 return ret; 305 } 306 307 spin_lock_init(&prtd->lock); 308 309 runtime->private_data = prtd; 310 311 return 0; 312 } 313 314 static int idma_close(struct snd_pcm_substream *substream) 315 { 316 struct snd_pcm_runtime *runtime = substream->runtime; 317 struct idma_ctrl *prtd = runtime->private_data; 318 319 free_irq(idma_irq, prtd); 320 321 if (!prtd) 322 pr_err("idma_close called with prtd == NULL\n"); 323 324 kfree(prtd); 325 326 return 0; 327 } 328 329 static struct snd_pcm_ops idma_ops = { 330 .open = idma_open, 331 .close = idma_close, 332 .ioctl = snd_pcm_lib_ioctl, 333 .trigger = idma_trigger, 334 .pointer = idma_pointer, 335 .mmap = idma_mmap, 336 .hw_params = idma_hw_params, 337 .hw_free = idma_hw_free, 338 .prepare = idma_prepare, 339 }; 340 341 static void idma_free(struct snd_pcm *pcm) 342 { 343 struct snd_pcm_substream *substream; 344 struct snd_dma_buffer *buf; 345 346 substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; 347 if (!substream) 348 return; 349 350 buf = &substream->dma_buffer; 351 if (!buf->area) 352 return; 353 354 iounmap((void __iomem *)buf->area); 355 356 buf->area = NULL; 357 buf->addr = 0; 358 } 359 360 static int preallocate_idma_buffer(struct snd_pcm *pcm, int stream) 361 { 362 struct snd_pcm_substream *substream = pcm->streams[stream].substream; 363 struct snd_dma_buffer *buf = &substream->dma_buffer; 364 365 buf->dev.dev = pcm->card->dev; 366 buf->private_data = NULL; 367 368 /* Assign PCM buffer pointers */ 369 buf->dev.type = SNDRV_DMA_TYPE_CONTINUOUS; 370 buf->addr = idma.lp_tx_addr; 371 buf->bytes = idma_hardware.buffer_bytes_max; 372 buf->area = (unsigned char * __force)ioremap(buf->addr, buf->bytes); 373 374 return 0; 375 } 376 377 static int idma_new(struct snd_soc_pcm_runtime *rtd) 378 { 379 struct snd_card *card = rtd->card->snd_card; 380 struct snd_pcm *pcm = rtd->pcm; 381 int ret; 382 383 ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32)); 384 if (ret) 385 return ret; 386 387 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) { 388 ret = preallocate_idma_buffer(pcm, 389 SNDRV_PCM_STREAM_PLAYBACK); 390 } 391 392 return ret; 393 } 394 395 void idma_reg_addr_init(void __iomem *regs, dma_addr_t addr) 396 { 397 spin_lock_init(&idma.lock); 398 idma.regs = regs; 399 idma.lp_tx_addr = addr; 400 } 401 EXPORT_SYMBOL_GPL(idma_reg_addr_init); 402 403 static struct snd_soc_platform_driver asoc_idma_platform = { 404 .ops = &idma_ops, 405 .pcm_new = idma_new, 406 .pcm_free = idma_free, 407 }; 408 409 static int asoc_idma_platform_probe(struct platform_device *pdev) 410 { 411 idma_irq = platform_get_irq(pdev, 0); 412 if (idma_irq < 0) 413 return idma_irq; 414 415 return devm_snd_soc_register_platform(&pdev->dev, &asoc_idma_platform); 416 } 417 418 static struct platform_driver asoc_idma_driver = { 419 .driver = { 420 .name = "samsung-idma", 421 .owner = THIS_MODULE, 422 }, 423 424 .probe = asoc_idma_platform_probe, 425 }; 426 427 module_platform_driver(asoc_idma_driver); 428 429 MODULE_AUTHOR("Jaswinder Singh, <jassisinghbrar@gmail.com>"); 430 MODULE_DESCRIPTION("Samsung ASoC IDMA Driver"); 431 MODULE_LICENSE("GPL"); 432