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
24static 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
38struct 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
50static struct idma_info {
51 spinlock_t lock;
52 void __iomem *regs;
53 dma_addr_t lp_tx_addr;
54} idma;
55
56static int idma_irq;
57
58static void idma_getpos(dma_addr_t *src)
59{
60 *src = idma.lp_tx_addr +
61 (readl(addr: idma.regs + I2STRNCNT) & 0xffffff) * 4;
62}
63
64static 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(lock: &prtd->lock);
71 prtd->token = (void *) substream;
72 spin_unlock(lock: &prtd->lock);
73
74 /* Internal DMA Level0 Interrupt Address */
75 val = idma.lp_tx_addr + prtd->periodsz;
76 writel(val, addr: idma.regs + I2SLVL0ADDR);
77
78 /* Start address0 of I2S internal DMA operation. */
79 val = idma.lp_tx_addr;
80 writel(val, addr: 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(addr: idma.regs + I2SSIZE);
87 val &= ~(I2SSIZE_TRNMSK << I2SSIZE_SHIFT);
88 val |= (((runtime->dma_bytes >> 2) &
89 I2SSIZE_TRNMSK) << I2SSIZE_SHIFT);
90 writel(val, addr: idma.regs + I2SSIZE);
91
92 val = readl(addr: idma.regs + I2SAHB);
93 val |= AHB_INTENLVL0;
94 writel(val, addr: idma.regs + I2SAHB);
95
96 return 0;
97}
98
99static 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(lock: &prtd->lock);
105 prtd->cb = cb;
106 spin_unlock(lock: &prtd->lock);
107}
108
109static void idma_control(int op)
110{
111 u32 val = readl(addr: idma.regs + I2SAHB);
112
113 spin_lock(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(lock: &idma.lock);
124 return;
125 }
126
127 writel(val, addr: idma.regs + I2SAHB);
128 spin_unlock(lock: &idma.lock);
129}
130
131static 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
140static 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(addr: idma.regs + I2SMOD);
147 u32 ahb = readl(addr: idma.regs + I2SAHB);
148
149 ahb |= (AHB_DMARLD | AHB_INTMASK);
150 mod |= MOD_TXS_IDMA;
151 writel(val: ahb, addr: idma.regs + I2SAHB);
152 writel(val: mod, addr: idma.regs + I2SMOD);
153
154 snd_pcm_set_runtime_buffer(substream, bufp: &substream->dma_buffer);
155 runtime->dma_bytes = params_buffer_bytes(p: params);
156
157 prtd->start = prtd->pos = runtime->dma_addr;
158 prtd->period = params_periods(p: params);
159 prtd->periodsz = params_period_bytes(p: params);
160 prtd->end = runtime->dma_addr + runtime->dma_bytes;
161
162 idma_setcallbk(substream, cb: idma_done);
163
164 return 0;
165}
166
167static 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
175static 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
189static 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(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(lock: &prtd->lock);
218
219 return ret;
220}
221
222static snd_pcm_uframes_t
223idma_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(lock: &prtd->lock);
232
233 idma_getpos(src: &src);
234 res = src - prtd->start;
235
236 spin_unlock(lock: &prtd->lock);
237
238 return bytes_to_frames(runtime: substream->runtime, size: res);
239}
240
241static 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, addr: vma->vm_start,
253 pfn: (runtime->dma_addr + offset) >> PAGE_SHIFT,
254 size, prot: vma->vm_page_prot);
255}
256
257static 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(addr: idma.regs + I2SAHB);
263
264 val = (iisahb & AHB_LVL0INT) ? AHB_CLRLVL0INT : 0;
265
266 if (val) {
267 iisahb |= val;
268 writel(val: iisahb, addr: idma.regs + I2SAHB);
269
270 addr = readl(addr: 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(val: addr, addr: idma.regs + I2SLVL0ADDR);
276
277 if (prtd->cb)
278 prtd->cb(prtd->token, prtd->period);
279 }
280
281 return IRQ_HANDLED;
282}
283
284static 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, hw: &idma_hardware);
292
293 prtd = kzalloc(size: sizeof(struct idma_ctrl), GFP_KERNEL);
294 if (prtd == NULL)
295 return -ENOMEM;
296
297 ret = request_irq(irq: idma_irq, handler: iis_irq, flags: 0, name: "i2s", dev: prtd);
298 if (ret < 0) {
299 pr_err("fail to claim i2s irq , ret = %d\n", ret);
300 kfree(objp: prtd);
301 return ret;
302 }
303
304 spin_lock_init(&prtd->lock);
305
306 runtime->private_data = prtd;
307
308 return 0;
309}
310
311static 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(objp: prtd);
323
324 return 0;
325}
326
327static 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(addr: (void __iomem *)buf->area);
342
343 buf->area = NULL;
344 buf->addr = 0;
345}
346
347static 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(offset: buf->addr, size: buf->bytes);
360 if (!buf->area)
361 return -ENOMEM;
362
363 return 0;
364}
365
366static 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(dev: 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 stream: SNDRV_PCM_STREAM_PLAYBACK);
380 }
381
382 return ret;
383}
384
385void 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}
391EXPORT_SYMBOL_GPL(idma_reg_addr_init);
392
393static 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
406static 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(dev: &pdev->dev, component_driver: &asoc_idma_platform,
413 NULL, num_dai: 0);
414}
415
416static struct platform_driver asoc_idma_driver = {
417 .driver = {
418 .name = "samsung-idma",
419 },
420
421 .probe = asoc_idma_platform_probe,
422};
423
424module_platform_driver(asoc_idma_driver);
425
426MODULE_AUTHOR("Jaswinder Singh, <jassisinghbrar@gmail.com>");
427MODULE_DESCRIPTION("Samsung ASoC IDMA Driver");
428MODULE_LICENSE("GPL");
429

source code of linux/sound/soc/samsung/idma.c