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_soc_component *component,
141 struct snd_pcm_substream *substream,
142 struct snd_pcm_hw_params *params)
143 {
144 struct snd_pcm_runtime *runtime = substream->runtime;
145 struct idma_ctrl *prtd = substream->runtime->private_data;
146 u32 mod = readl(idma.regs + I2SMOD);
147 u32 ahb = readl(idma.regs + I2SAHB);
148
149 ahb |= (AHB_DMARLD | AHB_INTMASK);
150 mod |= MOD_TXS_IDMA;
151 writel(ahb, idma.regs + I2SAHB);
152 writel(mod, idma.regs + I2SMOD);
153
154 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
155 runtime->dma_bytes = params_buffer_bytes(params);
156
157 prtd->start = prtd->pos = runtime->dma_addr;
158 prtd->period = params_periods(params);
159 prtd->periodsz = params_period_bytes(params);
160 prtd->end = runtime->dma_addr + runtime->dma_bytes;
161
162 idma_setcallbk(substream, idma_done);
163
164 return 0;
165 }
166
167 static int idma_hw_free(struct snd_soc_component *component,
168 struct snd_pcm_substream *substream)
169 {
170 snd_pcm_set_runtime_buffer(substream, NULL);
171
172 return 0;
173 }
174
175 static int idma_prepare(struct snd_soc_component *component,
176 struct snd_pcm_substream *substream)
177 {
178 struct idma_ctrl *prtd = substream->runtime->private_data;
179
180 prtd->pos = prtd->start;
181
182 /* flush the DMA channel */
183 idma_control(LPAM_DMA_STOP);
184 idma_enqueue(substream);
185
186 return 0;
187 }
188
189 static int idma_trigger(struct snd_soc_component *component,
190 struct snd_pcm_substream *substream, int cmd)
191 {
192 struct idma_ctrl *prtd = substream->runtime->private_data;
193 int ret = 0;
194
195 spin_lock(&prtd->lock);
196
197 switch (cmd) {
198 case SNDRV_PCM_TRIGGER_RESUME:
199 case SNDRV_PCM_TRIGGER_START:
200 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
201 prtd->state |= ST_RUNNING;
202 idma_control(LPAM_DMA_START);
203 break;
204
205 case SNDRV_PCM_TRIGGER_SUSPEND:
206 case SNDRV_PCM_TRIGGER_STOP:
207 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
208 prtd->state &= ~ST_RUNNING;
209 idma_control(LPAM_DMA_STOP);
210 break;
211
212 default:
213 ret = -EINVAL;
214 break;
215 }
216
217 spin_unlock(&prtd->lock);
218
219 return ret;
220 }
221
222 static snd_pcm_uframes_t
223 idma_pointer(struct snd_soc_component *component,
224 struct snd_pcm_substream *substream)
225 {
226 struct snd_pcm_runtime *runtime = substream->runtime;
227 struct idma_ctrl *prtd = runtime->private_data;
228 dma_addr_t src;
229 unsigned long res;
230
231 spin_lock(&prtd->lock);
232
233 idma_getpos(&src);
234 res = src - prtd->start;
235
236 spin_unlock(&prtd->lock);
237
238 return bytes_to_frames(substream->runtime, res);
239 }
240
241 static int idma_mmap(struct snd_soc_component *component,
242 struct snd_pcm_substream *substream,
243 struct vm_area_struct *vma)
244 {
245 struct snd_pcm_runtime *runtime = substream->runtime;
246 unsigned long size, offset;
247
248 /* From snd_pcm_lib_mmap_iomem */
249 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
250 size = vma->vm_end - vma->vm_start;
251 offset = vma->vm_pgoff << PAGE_SHIFT;
252 return io_remap_pfn_range(vma, vma->vm_start,
253 (runtime->dma_addr + offset) >> PAGE_SHIFT,
254 size, vma->vm_page_prot);
255 }
256
257 static irqreturn_t iis_irq(int irqno, void *dev_id)
258 {
259 struct idma_ctrl *prtd = (struct idma_ctrl *)dev_id;
260 u32 iisahb, val, addr;
261
262 iisahb = readl(idma.regs + I2SAHB);
263
264 val = (iisahb & AHB_LVL0INT) ? AHB_CLRLVL0INT : 0;
265
266 if (val) {
267 iisahb |= val;
268 writel(iisahb, idma.regs + I2SAHB);
269
270 addr = readl(idma.regs + I2SLVL0ADDR) - idma.lp_tx_addr;
271 addr += prtd->periodsz;
272 addr %= (u32)(prtd->end - prtd->start);
273 addr += idma.lp_tx_addr;
274
275 writel(addr, idma.regs + I2SLVL0ADDR);
276
277 if (prtd->cb)
278 prtd->cb(prtd->token, prtd->period);
279 }
280
281 return IRQ_HANDLED;
282 }
283
284 static int idma_open(struct snd_soc_component *component,
285 struct snd_pcm_substream *substream)
286 {
287 struct snd_pcm_runtime *runtime = substream->runtime;
288 struct idma_ctrl *prtd;
289 int ret;
290
291 snd_soc_set_runtime_hwparams(substream, &idma_hardware);
292
293 prtd = kzalloc(sizeof(struct idma_ctrl), GFP_KERNEL);
294 if (prtd == NULL)
295 return -ENOMEM;
296
297 ret = request_irq(idma_irq, iis_irq, 0, "i2s", prtd);
298 if (ret < 0) {
299 pr_err("fail to claim i2s irq , ret = %d\n", ret);
300 kfree(prtd);
301 return ret;
302 }
303
304 spin_lock_init(&prtd->lock);
305
306 runtime->private_data = prtd;
307
308 return 0;
309 }
310
311 static int idma_close(struct snd_soc_component *component,
312 struct snd_pcm_substream *substream)
313 {
314 struct snd_pcm_runtime *runtime = substream->runtime;
315 struct idma_ctrl *prtd = runtime->private_data;
316
317 free_irq(idma_irq, prtd);
318
319 if (!prtd)
320 pr_err("idma_close called with prtd == NULL\n");
321
322 kfree(prtd);
323
324 return 0;
325 }
326
327 static void idma_free(struct snd_soc_component *component,
328 struct snd_pcm *pcm)
329 {
330 struct snd_pcm_substream *substream;
331 struct snd_dma_buffer *buf;
332
333 substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
334 if (!substream)
335 return;
336
337 buf = &substream->dma_buffer;
338 if (!buf->area)
339 return;
340
341 iounmap((void __iomem *)buf->area);
342
343 buf->area = NULL;
344 buf->addr = 0;
345 }
346
347 static int preallocate_idma_buffer(struct snd_pcm *pcm, int stream)
348 {
349 struct snd_pcm_substream *substream = pcm->streams[stream].substream;
350 struct snd_dma_buffer *buf = &substream->dma_buffer;
351
352 buf->dev.dev = pcm->card->dev;
353 buf->private_data = NULL;
354
355 /* Assign PCM buffer pointers */
356 buf->dev.type = SNDRV_DMA_TYPE_CONTINUOUS;
357 buf->addr = idma.lp_tx_addr;
358 buf->bytes = idma_hardware.buffer_bytes_max;
359 buf->area = (unsigned char * __force)ioremap(buf->addr, buf->bytes);
360 if (!buf->area)
361 return -ENOMEM;
362
363 return 0;
364 }
365
366 static int idma_new(struct snd_soc_component *component,
367 struct snd_soc_pcm_runtime *rtd)
368 {
369 struct snd_card *card = rtd->card->snd_card;
370 struct snd_pcm *pcm = rtd->pcm;
371 int ret;
372
373 ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
374 if (ret)
375 return ret;
376
377 if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
378 ret = preallocate_idma_buffer(pcm,
379 SNDRV_PCM_STREAM_PLAYBACK);
380 }
381
382 return ret;
383 }
384
385 void idma_reg_addr_init(void __iomem *regs, dma_addr_t addr)
386 {
387 spin_lock_init(&idma.lock);
388 idma.regs = regs;
389 idma.lp_tx_addr = addr;
390 }
391 EXPORT_SYMBOL_GPL(idma_reg_addr_init);
392
393 static const struct snd_soc_component_driver asoc_idma_platform = {
394 .open = idma_open,
395 .close = idma_close,
396 .trigger = idma_trigger,
397 .pointer = idma_pointer,
398 .mmap = idma_mmap,
399 .hw_params = idma_hw_params,
400 .hw_free = idma_hw_free,
401 .prepare = idma_prepare,
402 .pcm_construct = idma_new,
403 .pcm_destruct = idma_free,
404 };
405
406 static int asoc_idma_platform_probe(struct platform_device *pdev)
407 {
408 idma_irq = platform_get_irq(pdev, 0);
409 if (idma_irq < 0)
410 return idma_irq;
411
412 return devm_snd_soc_register_component(&pdev->dev, &asoc_idma_platform,
413 NULL, 0);
414 }
415
416 static struct platform_driver asoc_idma_driver = {
417 .driver = {
418 .name = "samsung-idma",
419 },
420
421 .probe = asoc_idma_platform_probe,
422 };
423
424 module_platform_driver(asoc_idma_driver);
425
426 MODULE_AUTHOR("Jaswinder Singh, <jassisinghbrar@gmail.com>");
427 MODULE_DESCRIPTION("Samsung ASoC IDMA Driver");
428 MODULE_LICENSE("GPL");
429
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