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 scoped_guard(spinlock, &prtd->lock) 71 prtd->token = (void *) substream; 72 73 /* Internal DMA Level0 Interrupt Address */ 74 val = idma.lp_tx_addr + prtd->periodsz; 75 writel(val, idma.regs + I2SLVL0ADDR); 76 77 /* Start address0 of I2S internal DMA operation. */ 78 val = idma.lp_tx_addr; 79 writel(val, idma.regs + I2SSTR0); 80 81 /* 82 * Transfer block size for I2S internal DMA. 83 * Should decide transfer size before start dma operation 84 */ 85 val = readl(idma.regs + I2SSIZE); 86 val &= ~(I2SSIZE_TRNMSK << I2SSIZE_SHIFT); 87 val |= (((runtime->dma_bytes >> 2) & 88 I2SSIZE_TRNMSK) << I2SSIZE_SHIFT); 89 writel(val, idma.regs + I2SSIZE); 90 91 val = readl(idma.regs + I2SAHB); 92 val |= AHB_INTENLVL0; 93 writel(val, idma.regs + I2SAHB); 94 95 return 0; 96 } 97 98 static void idma_setcallbk(struct snd_pcm_substream *substream, 99 void (*cb)(void *, int)) 100 { 101 struct idma_ctrl *prtd = substream->runtime->private_data; 102 103 guard(spinlock)(&prtd->lock); 104 prtd->cb = cb; 105 } 106 107 static void idma_control(int op) 108 { 109 u32 val = readl(idma.regs + I2SAHB); 110 111 guard(spinlock)(&idma.lock); 112 113 switch (op) { 114 case LPAM_DMA_START: 115 val |= (AHB_INTENLVL0 | AHB_DMAEN); 116 break; 117 case LPAM_DMA_STOP: 118 val &= ~(AHB_INTENLVL0 | AHB_DMAEN); 119 break; 120 default: 121 return; 122 } 123 124 writel(val, idma.regs + I2SAHB); 125 } 126 127 static void idma_done(void *id, int bytes_xfer) 128 { 129 struct snd_pcm_substream *substream = id; 130 struct idma_ctrl *prtd = substream->runtime->private_data; 131 132 if (prtd && (prtd->state & ST_RUNNING)) 133 snd_pcm_period_elapsed(substream); 134 } 135 136 static int idma_hw_params(struct snd_soc_component *component, 137 struct snd_pcm_substream *substream, 138 struct snd_pcm_hw_params *params) 139 { 140 struct snd_pcm_runtime *runtime = substream->runtime; 141 struct idma_ctrl *prtd = substream->runtime->private_data; 142 u32 mod = readl(idma.regs + I2SMOD); 143 u32 ahb = readl(idma.regs + I2SAHB); 144 145 ahb |= (AHB_DMARLD | AHB_INTMASK); 146 mod |= MOD_TXS_IDMA; 147 writel(ahb, idma.regs + I2SAHB); 148 writel(mod, idma.regs + I2SMOD); 149 150 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); 151 runtime->dma_bytes = params_buffer_bytes(params); 152 153 prtd->start = prtd->pos = runtime->dma_addr; 154 prtd->period = params_periods(params); 155 prtd->periodsz = params_period_bytes(params); 156 prtd->end = runtime->dma_addr + runtime->dma_bytes; 157 158 idma_setcallbk(substream, idma_done); 159 160 return 0; 161 } 162 163 static int idma_hw_free(struct snd_soc_component *component, 164 struct snd_pcm_substream *substream) 165 { 166 snd_pcm_set_runtime_buffer(substream, NULL); 167 168 return 0; 169 } 170 171 static int idma_prepare(struct snd_soc_component *component, 172 struct snd_pcm_substream *substream) 173 { 174 struct idma_ctrl *prtd = substream->runtime->private_data; 175 176 prtd->pos = prtd->start; 177 178 /* flush the DMA channel */ 179 idma_control(LPAM_DMA_STOP); 180 idma_enqueue(substream); 181 182 return 0; 183 } 184 185 static int idma_trigger(struct snd_soc_component *component, 186 struct snd_pcm_substream *substream, int cmd) 187 { 188 struct idma_ctrl *prtd = substream->runtime->private_data; 189 int ret = 0; 190 191 guard(spinlock)(&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 return ret; 214 } 215 216 static snd_pcm_uframes_t 217 idma_pointer(struct snd_soc_component *component, 218 struct snd_pcm_substream *substream) 219 { 220 struct snd_pcm_runtime *runtime = substream->runtime; 221 struct idma_ctrl *prtd = runtime->private_data; 222 dma_addr_t src; 223 unsigned long res; 224 225 scoped_guard(spinlock, &prtd->lock) { 226 idma_getpos(&src); 227 res = src - prtd->start; 228 } 229 230 return bytes_to_frames(substream->runtime, res); 231 } 232 233 static int idma_mmap(struct snd_soc_component *component, 234 struct snd_pcm_substream *substream, 235 struct vm_area_struct *vma) 236 { 237 struct snd_pcm_runtime *runtime = substream->runtime; 238 unsigned long size, offset; 239 240 /* From snd_pcm_lib_mmap_iomem */ 241 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); 242 size = vma->vm_end - vma->vm_start; 243 offset = vma->vm_pgoff << PAGE_SHIFT; 244 return io_remap_pfn_range(vma, vma->vm_start, 245 (runtime->dma_addr + offset) >> PAGE_SHIFT, 246 size, vma->vm_page_prot); 247 } 248 249 static irqreturn_t iis_irq(int irqno, void *dev_id) 250 { 251 struct idma_ctrl *prtd = (struct idma_ctrl *)dev_id; 252 u32 iisahb, val, addr; 253 254 iisahb = readl(idma.regs + I2SAHB); 255 256 val = (iisahb & AHB_LVL0INT) ? AHB_CLRLVL0INT : 0; 257 258 if (val) { 259 iisahb |= val; 260 writel(iisahb, idma.regs + I2SAHB); 261 262 addr = readl(idma.regs + I2SLVL0ADDR) - idma.lp_tx_addr; 263 addr += prtd->periodsz; 264 addr %= (u32)(prtd->end - prtd->start); 265 addr += idma.lp_tx_addr; 266 267 writel(addr, idma.regs + I2SLVL0ADDR); 268 269 if (prtd->cb) 270 prtd->cb(prtd->token, prtd->period); 271 } 272 273 return IRQ_HANDLED; 274 } 275 276 static int idma_open(struct snd_soc_component *component, 277 struct snd_pcm_substream *substream) 278 { 279 struct snd_pcm_runtime *runtime = substream->runtime; 280 struct idma_ctrl *prtd; 281 int ret; 282 283 snd_soc_set_runtime_hwparams(substream, &idma_hardware); 284 285 prtd = kzalloc_obj(struct idma_ctrl); 286 if (prtd == NULL) 287 return -ENOMEM; 288 289 ret = request_irq(idma_irq, iis_irq, 0, "i2s", prtd); 290 if (ret < 0) { 291 pr_err("fail to claim i2s irq , ret = %d\n", ret); 292 kfree(prtd); 293 return ret; 294 } 295 296 spin_lock_init(&prtd->lock); 297 298 runtime->private_data = prtd; 299 300 return 0; 301 } 302 303 static int idma_close(struct snd_soc_component *component, 304 struct snd_pcm_substream *substream) 305 { 306 struct snd_pcm_runtime *runtime = substream->runtime; 307 struct idma_ctrl *prtd = runtime->private_data; 308 309 free_irq(idma_irq, prtd); 310 311 if (!prtd) 312 pr_err("idma_close called with prtd == NULL\n"); 313 314 kfree(prtd); 315 316 return 0; 317 } 318 319 static void idma_free(struct snd_soc_component *component, 320 struct snd_pcm *pcm) 321 { 322 struct snd_pcm_substream *substream; 323 struct snd_dma_buffer *buf; 324 325 substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream; 326 if (!substream) 327 return; 328 329 buf = &substream->dma_buffer; 330 if (!buf->area) 331 return; 332 333 iounmap((void __iomem *)buf->area); 334 335 buf->area = NULL; 336 buf->addr = 0; 337 } 338 339 static int preallocate_idma_buffer(struct snd_pcm *pcm, int stream) 340 { 341 struct snd_pcm_substream *substream = pcm->streams[stream].substream; 342 struct snd_dma_buffer *buf = &substream->dma_buffer; 343 344 buf->dev.dev = pcm->card->dev; 345 buf->private_data = NULL; 346 347 /* Assign PCM buffer pointers */ 348 buf->dev.type = SNDRV_DMA_TYPE_CONTINUOUS; 349 buf->addr = idma.lp_tx_addr; 350 buf->bytes = idma_hardware.buffer_bytes_max; 351 buf->area = (unsigned char * __force)ioremap(buf->addr, buf->bytes); 352 if (!buf->area) 353 return -ENOMEM; 354 355 return 0; 356 } 357 358 static int idma_new(struct snd_soc_component *component, 359 struct snd_soc_pcm_runtime *rtd) 360 { 361 struct snd_card *card = rtd->card->snd_card; 362 struct snd_pcm *pcm = rtd->pcm; 363 int ret; 364 365 ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32)); 366 if (ret) 367 return ret; 368 369 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) { 370 ret = preallocate_idma_buffer(pcm, 371 SNDRV_PCM_STREAM_PLAYBACK); 372 } 373 374 return ret; 375 } 376 377 void idma_reg_addr_init(void __iomem *regs, dma_addr_t addr) 378 { 379 spin_lock_init(&idma.lock); 380 idma.regs = regs; 381 idma.lp_tx_addr = addr; 382 } 383 EXPORT_SYMBOL_GPL(idma_reg_addr_init); 384 385 static const struct snd_soc_component_driver asoc_idma_platform = { 386 .open = idma_open, 387 .close = idma_close, 388 .trigger = idma_trigger, 389 .pointer = idma_pointer, 390 .mmap = idma_mmap, 391 .hw_params = idma_hw_params, 392 .hw_free = idma_hw_free, 393 .prepare = idma_prepare, 394 .pcm_new = idma_new, 395 .pcm_free = idma_free, 396 }; 397 398 static int asoc_idma_platform_probe(struct platform_device *pdev) 399 { 400 idma_irq = platform_get_irq(pdev, 0); 401 if (idma_irq < 0) 402 return idma_irq; 403 404 return devm_snd_soc_register_component(&pdev->dev, &asoc_idma_platform, 405 NULL, 0); 406 } 407 408 static struct platform_driver asoc_idma_driver = { 409 .driver = { 410 .name = "samsung-idma", 411 }, 412 413 .probe = asoc_idma_platform_probe, 414 }; 415 416 module_platform_driver(asoc_idma_driver); 417 418 MODULE_AUTHOR("Jaswinder Singh, <jassisinghbrar@gmail.com>"); 419 MODULE_DESCRIPTION("Samsung ASoC IDMA Driver"); 420 MODULE_LICENSE("GPL"); 421