1 // SPDX-License-Identifier: GPL-2.0+ 2 // 3 // idma.c - I2S0 internal DMA driver 4 // 5 // Copyright (c) 2011 Samsung Electronics Co., Ltd. 6 // http://www.samsung.com 7 8 #include <linux/interrupt.h> 9 #include <linux/platform_device.h> 10 #include <linux/dma-mapping.h> 11 #include <linux/slab.h> 12 #include <linux/module.h> 13 #include <sound/pcm.h> 14 #include <sound/pcm_params.h> 15 #include <sound/soc.h> 16 17 #include "i2s.h" 18 #include "idma.h" 19 #include "i2s-regs.h" 20 21 #define ST_RUNNING (1<<0) 22 #define ST_OPENED (1<<1) 23 24 static const struct snd_pcm_hardware idma_hardware = { 25 .info = SNDRV_PCM_INFO_INTERLEAVED | 26 SNDRV_PCM_INFO_BLOCK_TRANSFER | 27 SNDRV_PCM_INFO_MMAP | 28 SNDRV_PCM_INFO_MMAP_VALID | 29 SNDRV_PCM_INFO_PAUSE | 30 SNDRV_PCM_INFO_RESUME, 31 .buffer_bytes_max = MAX_IDMA_BUFFER, 32 .period_bytes_min = 128, 33 .period_bytes_max = MAX_IDMA_PERIOD, 34 .periods_min = 1, 35 .periods_max = 2, 36 }; 37 38 struct idma_ctrl { 39 spinlock_t lock; 40 int state; 41 dma_addr_t start; 42 dma_addr_t pos; 43 dma_addr_t end; 44 dma_addr_t period; 45 dma_addr_t periodsz; 46 void *token; 47 void (*cb)(void *dt, int bytes_xfer); 48 }; 49 50 static struct idma_info { 51 spinlock_t lock; 52 void __iomem *regs; 53 dma_addr_t lp_tx_addr; 54 } idma; 55 56 static int idma_irq; 57 58 static void idma_getpos(dma_addr_t *src) 59 { 60 *src = idma.lp_tx_addr + 61 (readl(idma.regs + I2STRNCNT) & 0xffffff) * 4; 62 } 63 64 static int idma_enqueue(struct snd_pcm_substream *substream) 65 { 66 struct snd_pcm_runtime *runtime = substream->runtime; 67 struct idma_ctrl *prtd = substream->runtime->private_data; 68 u32 val; 69 70 spin_lock(&prtd->lock); 71 prtd->token = (void *) substream; 72 spin_unlock(&prtd->lock); 73 74 /* Internal DMA Level0 Interrupt Address */ 75 val = idma.lp_tx_addr + prtd->periodsz; 76 writel(val, idma.regs + I2SLVL0ADDR); 77 78 /* Start address0 of I2S internal DMA operation. */ 79 val = idma.lp_tx_addr; 80 writel(val, idma.regs + I2SSTR0); 81 82 /* 83 * Transfer block size for I2S internal DMA. 84 * Should decide transfer size before start dma operation 85 */ 86 val = readl(idma.regs + I2SSIZE); 87 val &= ~(I2SSIZE_TRNMSK << I2SSIZE_SHIFT); 88 val |= (((runtime->dma_bytes >> 2) & 89 I2SSIZE_TRNMSK) << I2SSIZE_SHIFT); 90 writel(val, idma.regs + I2SSIZE); 91 92 val = readl(idma.regs + I2SAHB); 93 val |= AHB_INTENLVL0; 94 writel(val, idma.regs + I2SAHB); 95 96 return 0; 97 } 98 99 static void idma_setcallbk(struct snd_pcm_substream *substream, 100 void (*cb)(void *, int)) 101 { 102 struct idma_ctrl *prtd = substream->runtime->private_data; 103 104 spin_lock(&prtd->lock); 105 prtd->cb = cb; 106 spin_unlock(&prtd->lock); 107 } 108 109 static void idma_control(int op) 110 { 111 u32 val = readl(idma.regs + I2SAHB); 112 113 spin_lock(&idma.lock); 114 115 switch (op) { 116 case LPAM_DMA_START: 117 val |= (AHB_INTENLVL0 | AHB_DMAEN); 118 break; 119 case LPAM_DMA_STOP: 120 val &= ~(AHB_INTENLVL0 | AHB_DMAEN); 121 break; 122 default: 123 spin_unlock(&idma.lock); 124 return; 125 } 126 127 writel(val, idma.regs + I2SAHB); 128 spin_unlock(&idma.lock); 129 } 130 131 static void idma_done(void *id, int bytes_xfer) 132 { 133 struct snd_pcm_substream *substream = id; 134 struct idma_ctrl *prtd = substream->runtime->private_data; 135 136 if (prtd && (prtd->state & ST_RUNNING)) 137 snd_pcm_period_elapsed(substream); 138 } 139 140 static int idma_hw_params(struct snd_pcm_substream *substream, 141 struct snd_pcm_hw_params *params) 142 { 143 struct snd_pcm_runtime *runtime = substream->runtime; 144 struct idma_ctrl *prtd = substream->runtime->private_data; 145 u32 mod = readl(idma.regs + I2SMOD); 146 u32 ahb = readl(idma.regs + I2SAHB); 147 148 ahb |= (AHB_DMARLD | AHB_INTMASK); 149 mod |= MOD_TXS_IDMA; 150 writel(ahb, idma.regs + I2SAHB); 151 writel(mod, idma.regs + I2SMOD); 152 153 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); 154 runtime->dma_bytes = params_buffer_bytes(params); 155 156 prtd->start = prtd->pos = runtime->dma_addr; 157 prtd->period = params_periods(params); 158 prtd->periodsz = params_period_bytes(params); 159 prtd->end = runtime->dma_addr + runtime->dma_bytes; 160 161 idma_setcallbk(substream, idma_done); 162 163 return 0; 164 } 165 166 static int idma_hw_free(struct snd_pcm_substream *substream) 167 { 168 snd_pcm_set_runtime_buffer(substream, NULL); 169 170 return 0; 171 } 172 173 static int idma_prepare(struct snd_pcm_substream *substream) 174 { 175 struct idma_ctrl *prtd = substream->runtime->private_data; 176 177 prtd->pos = prtd->start; 178 179 /* flush the DMA channel */ 180 idma_control(LPAM_DMA_STOP); 181 idma_enqueue(substream); 182 183 return 0; 184 } 185 186 static int idma_trigger(struct snd_pcm_substream *substream, int cmd) 187 { 188 struct idma_ctrl *prtd = substream->runtime->private_data; 189 int ret = 0; 190 191 spin_lock(&prtd->lock); 192 193 switch (cmd) { 194 case SNDRV_PCM_TRIGGER_RESUME: 195 case SNDRV_PCM_TRIGGER_START: 196 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: 197 prtd->state |= ST_RUNNING; 198 idma_control(LPAM_DMA_START); 199 break; 200 201 case SNDRV_PCM_TRIGGER_SUSPEND: 202 case SNDRV_PCM_TRIGGER_STOP: 203 case SNDRV_PCM_TRIGGER_PAUSE_PUSH: 204 prtd->state &= ~ST_RUNNING; 205 idma_control(LPAM_DMA_STOP); 206 break; 207 208 default: 209 ret = -EINVAL; 210 break; 211 } 212 213 spin_unlock(&prtd->lock); 214 215 return ret; 216 } 217 218 static snd_pcm_uframes_t 219 idma_pointer(struct snd_pcm_substream *substream) 220 { 221 struct snd_pcm_runtime *runtime = substream->runtime; 222 struct idma_ctrl *prtd = runtime->private_data; 223 dma_addr_t src; 224 unsigned long res; 225 226 spin_lock(&prtd->lock); 227 228 idma_getpos(&src); 229 res = src - prtd->start; 230 231 spin_unlock(&prtd->lock); 232 233 return bytes_to_frames(substream->runtime, res); 234 } 235 236 static int idma_mmap(struct snd_pcm_substream *substream, 237 struct vm_area_struct *vma) 238 { 239 struct snd_pcm_runtime *runtime = substream->runtime; 240 unsigned long size, offset; 241 int ret; 242 243 /* From snd_pcm_lib_mmap_iomem */ 244 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); 245 size = vma->vm_end - vma->vm_start; 246 offset = vma->vm_pgoff << PAGE_SHIFT; 247 ret = io_remap_pfn_range(vma, vma->vm_start, 248 (runtime->dma_addr + offset) >> PAGE_SHIFT, 249 size, vma->vm_page_prot); 250 251 return ret; 252 } 253 254 static irqreturn_t iis_irq(int irqno, void *dev_id) 255 { 256 struct idma_ctrl *prtd = (struct idma_ctrl *)dev_id; 257 u32 iisahb, val, addr; 258 259 iisahb = readl(idma.regs + I2SAHB); 260 261 val = (iisahb & AHB_LVL0INT) ? AHB_CLRLVL0INT : 0; 262 263 if (val) { 264 iisahb |= val; 265 writel(iisahb, idma.regs + I2SAHB); 266 267 addr = readl(idma.regs + I2SLVL0ADDR) - idma.lp_tx_addr; 268 addr += prtd->periodsz; 269 addr %= (u32)(prtd->end - prtd->start); 270 addr += idma.lp_tx_addr; 271 272 writel(addr, idma.regs + I2SLVL0ADDR); 273 274 if (prtd->cb) 275 prtd->cb(prtd->token, prtd->period); 276 } 277 278 return IRQ_HANDLED; 279 } 280 281 static int idma_open(struct snd_pcm_substream *substream) 282 { 283 struct snd_pcm_runtime *runtime = substream->runtime; 284 struct idma_ctrl *prtd; 285 int ret; 286 287 snd_soc_set_runtime_hwparams(substream, &idma_hardware); 288 289 prtd = kzalloc(sizeof(struct idma_ctrl), GFP_KERNEL); 290 if (prtd == NULL) 291 return -ENOMEM; 292 293 ret = request_irq(idma_irq, iis_irq, 0, "i2s", prtd); 294 if (ret < 0) { 295 pr_err("fail to claim i2s irq , ret = %d\n", ret); 296 kfree(prtd); 297 return ret; 298 } 299 300 spin_lock_init(&prtd->lock); 301 302 runtime->private_data = prtd; 303 304 return 0; 305 } 306 307 static int idma_close(struct snd_pcm_substream *substream) 308 { 309 struct snd_pcm_runtime *runtime = substream->runtime; 310 struct idma_ctrl *prtd = runtime->private_data; 311 312 free_irq(idma_irq, prtd); 313 314 if (!prtd) 315 pr_err("idma_close called with prtd == NULL\n"); 316 317 kfree(prtd); 318 319 return 0; 320 } 321 322 static const struct snd_pcm_ops idma_ops = { 323 .open = idma_open, 324 .close = idma_close, 325 .ioctl = snd_pcm_lib_ioctl, 326 .trigger = idma_trigger, 327 .pointer = idma_pointer, 328 .mmap = idma_mmap, 329 .hw_params = idma_hw_params, 330 .hw_free = idma_hw_free, 331 .prepare = idma_prepare, 332 }; 333 334 static void idma_free(struct snd_pcm *pcm) 335 { 336 struct snd_pcm_substream *substream; 337 struct snd_dma_buffer *buf; 338 339 substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; 340 if (!substream) 341 return; 342 343 buf = &substream->dma_buffer; 344 if (!buf->area) 345 return; 346 347 iounmap((void __iomem *)buf->area); 348 349 buf->area = NULL; 350 buf->addr = 0; 351 } 352 353 static int preallocate_idma_buffer(struct snd_pcm *pcm, int stream) 354 { 355 struct snd_pcm_substream *substream = pcm->streams[stream].substream; 356 struct snd_dma_buffer *buf = &substream->dma_buffer; 357 358 buf->dev.dev = pcm->card->dev; 359 buf->private_data = NULL; 360 361 /* Assign PCM buffer pointers */ 362 buf->dev.type = SNDRV_DMA_TYPE_CONTINUOUS; 363 buf->addr = idma.lp_tx_addr; 364 buf->bytes = idma_hardware.buffer_bytes_max; 365 buf->area = (unsigned char * __force)ioremap(buf->addr, buf->bytes); 366 367 return 0; 368 } 369 370 static int idma_new(struct snd_soc_pcm_runtime *rtd) 371 { 372 struct snd_card *card = rtd->card->snd_card; 373 struct snd_pcm *pcm = rtd->pcm; 374 int ret; 375 376 ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32)); 377 if (ret) 378 return ret; 379 380 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) { 381 ret = preallocate_idma_buffer(pcm, 382 SNDRV_PCM_STREAM_PLAYBACK); 383 } 384 385 return ret; 386 } 387 388 void idma_reg_addr_init(void __iomem *regs, dma_addr_t addr) 389 { 390 spin_lock_init(&idma.lock); 391 idma.regs = regs; 392 idma.lp_tx_addr = addr; 393 } 394 EXPORT_SYMBOL_GPL(idma_reg_addr_init); 395 396 static const struct snd_soc_component_driver asoc_idma_platform = { 397 .ops = &idma_ops, 398 .pcm_new = idma_new, 399 .pcm_free = idma_free, 400 }; 401 402 static int asoc_idma_platform_probe(struct platform_device *pdev) 403 { 404 idma_irq = platform_get_irq(pdev, 0); 405 if (idma_irq < 0) 406 return idma_irq; 407 408 return devm_snd_soc_register_component(&pdev->dev, &asoc_idma_platform, 409 NULL, 0); 410 } 411 412 static struct platform_driver asoc_idma_driver = { 413 .driver = { 414 .name = "samsung-idma", 415 }, 416 417 .probe = asoc_idma_platform_probe, 418 }; 419 420 module_platform_driver(asoc_idma_driver); 421 422 MODULE_AUTHOR("Jaswinder Singh, <jassisinghbrar@gmail.com>"); 423 MODULE_DESCRIPTION("Samsung ASoC IDMA Driver"); 424 MODULE_LICENSE("GPL"); 425