1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * atmel-pcm.c -- ALSA PCM interface for the Atmel atmel SoC.
4 *
5 * Copyright (C) 2005 SAN People
6 * Copyright (C) 2008 Atmel
7 *
8 * Authors: Sedji Gaouaou <sedji.gaouaou@atmel.com>
9 *
10 * Based on at91-pcm. by:
11 * Frank Mandarino <fmandarino@endrelia.com>
12 * Copyright 2006 Endrelia Technologies Inc.
13 *
14 * Based on pxa2xx-pcm.c by:
15 *
16 * Author: Nicolas Pitre
17 * Created: Nov 30, 2004
18 * Copyright: (C) 2004 MontaVista Software, Inc.
19 */
20
21 #include <linux/module.h>
22 #include <linux/init.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include <linux/dma-mapping.h>
26 #include <linux/atmel_pdc.h>
27 #include <linux/atmel-ssc.h>
28
29 #include <sound/core.h>
30 #include <sound/pcm.h>
31 #include <sound/pcm_params.h>
32 #include <sound/soc.h>
33
34 #include "atmel-pcm.h"
35
36
atmel_pcm_new(struct snd_soc_component * component,struct snd_soc_pcm_runtime * rtd)37 static int atmel_pcm_new(struct snd_soc_component *component,
38 struct snd_soc_pcm_runtime *rtd)
39 {
40 struct snd_card *card = rtd->card->snd_card;
41 int ret;
42
43 ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
44 if (ret)
45 return ret;
46
47 snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
48 card->dev, ATMEL_SSC_DMABUF_SIZE,
49 ATMEL_SSC_DMABUF_SIZE);
50
51 return 0;
52 }
53
54 /*--------------------------------------------------------------------------*\
55 * Hardware definition
56 \*--------------------------------------------------------------------------*/
57 /* TODO: These values were taken from the AT91 platform driver, check
58 * them against real values for AT32
59 */
60 static const struct snd_pcm_hardware atmel_pcm_hardware = {
61 .info = SNDRV_PCM_INFO_MMAP |
62 SNDRV_PCM_INFO_MMAP_VALID |
63 SNDRV_PCM_INFO_INTERLEAVED |
64 SNDRV_PCM_INFO_PAUSE,
65 .period_bytes_min = 32,
66 .period_bytes_max = 8192,
67 .periods_min = 2,
68 .periods_max = 1024,
69 .buffer_bytes_max = ATMEL_SSC_DMABUF_SIZE,
70 };
71
72
73 /*--------------------------------------------------------------------------*\
74 * Data types
75 \*--------------------------------------------------------------------------*/
76 struct atmel_runtime_data {
77 struct atmel_pcm_dma_params *params;
78 dma_addr_t dma_buffer; /* physical address of dma buffer */
79 dma_addr_t dma_buffer_end; /* first address beyond DMA buffer */
80 size_t period_size;
81
82 dma_addr_t period_ptr; /* physical address of next period */
83 };
84
85 /*--------------------------------------------------------------------------*\
86 * ISR
87 \*--------------------------------------------------------------------------*/
atmel_pcm_dma_irq(u32 ssc_sr,struct snd_pcm_substream * substream)88 static void atmel_pcm_dma_irq(u32 ssc_sr,
89 struct snd_pcm_substream *substream)
90 {
91 struct atmel_runtime_data *prtd = substream->runtime->private_data;
92 struct atmel_pcm_dma_params *params = prtd->params;
93 static int count;
94
95 count++;
96
97 if (ssc_sr & params->mask->ssc_endbuf) {
98 pr_warn("atmel-pcm: buffer %s on %s (SSC_SR=%#x, count=%d)\n",
99 substream->stream == SNDRV_PCM_STREAM_PLAYBACK
100 ? "underrun" : "overrun",
101 params->name, ssc_sr, count);
102
103 /* re-start the PDC */
104 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
105 params->mask->pdc_disable);
106 prtd->period_ptr += prtd->period_size;
107 if (prtd->period_ptr >= prtd->dma_buffer_end)
108 prtd->period_ptr = prtd->dma_buffer;
109
110 ssc_writex(params->ssc->regs, params->pdc->xpr,
111 prtd->period_ptr);
112 ssc_writex(params->ssc->regs, params->pdc->xcr,
113 prtd->period_size / params->pdc_xfer_size);
114 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
115 params->mask->pdc_enable);
116 }
117
118 if (ssc_sr & params->mask->ssc_endx) {
119 /* Load the PDC next pointer and counter registers */
120 prtd->period_ptr += prtd->period_size;
121 if (prtd->period_ptr >= prtd->dma_buffer_end)
122 prtd->period_ptr = prtd->dma_buffer;
123
124 ssc_writex(params->ssc->regs, params->pdc->xnpr,
125 prtd->period_ptr);
126 ssc_writex(params->ssc->regs, params->pdc->xncr,
127 prtd->period_size / params->pdc_xfer_size);
128 }
129
130 snd_pcm_period_elapsed(substream);
131 }
132
133
134 /*--------------------------------------------------------------------------*\
135 * PCM operations
136 \*--------------------------------------------------------------------------*/
atmel_pcm_hw_params(struct snd_soc_component * component,struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params)137 static int atmel_pcm_hw_params(struct snd_soc_component *component,
138 struct snd_pcm_substream *substream,
139 struct snd_pcm_hw_params *params)
140 {
141 struct snd_pcm_runtime *runtime = substream->runtime;
142 struct atmel_runtime_data *prtd = runtime->private_data;
143 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
144
145 /* this may get called several times by oss emulation
146 * with different params */
147
148 prtd->params = snd_soc_dai_get_dma_data(snd_soc_rtd_to_cpu(rtd, 0), substream);
149 prtd->params->dma_intr_handler = atmel_pcm_dma_irq;
150
151 prtd->dma_buffer = runtime->dma_addr;
152 prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes;
153 prtd->period_size = params_period_bytes(params);
154
155 pr_debug("atmel-pcm: "
156 "hw_params: DMA for %s initialized "
157 "(dma_bytes=%zu, period_size=%zu)\n",
158 prtd->params->name,
159 runtime->dma_bytes,
160 prtd->period_size);
161 return 0;
162 }
163
atmel_pcm_hw_free(struct snd_soc_component * component,struct snd_pcm_substream * substream)164 static int atmel_pcm_hw_free(struct snd_soc_component *component,
165 struct snd_pcm_substream *substream)
166 {
167 struct atmel_runtime_data *prtd = substream->runtime->private_data;
168 struct atmel_pcm_dma_params *params = prtd->params;
169
170 if (params != NULL) {
171 ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
172 params->mask->pdc_disable);
173 prtd->params->dma_intr_handler = NULL;
174 }
175
176 return 0;
177 }
178
atmel_pcm_prepare(struct snd_soc_component * component,struct snd_pcm_substream * substream)179 static int atmel_pcm_prepare(struct snd_soc_component *component,
180 struct snd_pcm_substream *substream)
181 {
182 struct atmel_runtime_data *prtd = substream->runtime->private_data;
183 struct atmel_pcm_dma_params *params = prtd->params;
184
185 ssc_writex(params->ssc->regs, SSC_IDR,
186 params->mask->ssc_endx | params->mask->ssc_endbuf);
187 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
188 params->mask->pdc_disable);
189 return 0;
190 }
191
atmel_pcm_trigger(struct snd_soc_component * component,struct snd_pcm_substream * substream,int cmd)192 static int atmel_pcm_trigger(struct snd_soc_component *component,
193 struct snd_pcm_substream *substream, int cmd)
194 {
195 struct snd_pcm_runtime *rtd = substream->runtime;
196 struct atmel_runtime_data *prtd = rtd->private_data;
197 struct atmel_pcm_dma_params *params = prtd->params;
198 int ret = 0;
199
200 pr_debug("atmel-pcm:buffer_size = %ld,"
201 "dma_area = %p, dma_bytes = %zu\n",
202 rtd->buffer_size, rtd->dma_area, rtd->dma_bytes);
203
204 switch (cmd) {
205 case SNDRV_PCM_TRIGGER_START:
206 prtd->period_ptr = prtd->dma_buffer;
207
208 ssc_writex(params->ssc->regs, params->pdc->xpr,
209 prtd->period_ptr);
210 ssc_writex(params->ssc->regs, params->pdc->xcr,
211 prtd->period_size / params->pdc_xfer_size);
212
213 prtd->period_ptr += prtd->period_size;
214 ssc_writex(params->ssc->regs, params->pdc->xnpr,
215 prtd->period_ptr);
216 ssc_writex(params->ssc->regs, params->pdc->xncr,
217 prtd->period_size / params->pdc_xfer_size);
218
219 pr_debug("atmel-pcm: trigger: "
220 "period_ptr=%lx, xpr=%u, "
221 "xcr=%u, xnpr=%u, xncr=%u\n",
222 (unsigned long)prtd->period_ptr,
223 ssc_readx(params->ssc->regs, params->pdc->xpr),
224 ssc_readx(params->ssc->regs, params->pdc->xcr),
225 ssc_readx(params->ssc->regs, params->pdc->xnpr),
226 ssc_readx(params->ssc->regs, params->pdc->xncr));
227
228 ssc_writex(params->ssc->regs, SSC_IER,
229 params->mask->ssc_endx | params->mask->ssc_endbuf);
230 ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
231 params->mask->pdc_enable);
232
233 pr_debug("sr=%u imr=%u\n",
234 ssc_readx(params->ssc->regs, SSC_SR),
235 ssc_readx(params->ssc->regs, SSC_IER));
236 break; /* SNDRV_PCM_TRIGGER_START */
237
238 case SNDRV_PCM_TRIGGER_STOP:
239 case SNDRV_PCM_TRIGGER_SUSPEND:
240 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
241 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
242 params->mask->pdc_disable);
243 break;
244
245 case SNDRV_PCM_TRIGGER_RESUME:
246 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
247 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
248 params->mask->pdc_enable);
249 break;
250
251 default:
252 ret = -EINVAL;
253 }
254
255 return ret;
256 }
257
atmel_pcm_pointer(struct snd_soc_component * component,struct snd_pcm_substream * substream)258 static snd_pcm_uframes_t atmel_pcm_pointer(struct snd_soc_component *component,
259 struct snd_pcm_substream *substream)
260 {
261 struct snd_pcm_runtime *runtime = substream->runtime;
262 struct atmel_runtime_data *prtd = runtime->private_data;
263 struct atmel_pcm_dma_params *params = prtd->params;
264 dma_addr_t ptr;
265 snd_pcm_uframes_t x;
266
267 ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr);
268 x = bytes_to_frames(runtime, ptr - prtd->dma_buffer);
269
270 if (x == runtime->buffer_size)
271 x = 0;
272
273 return x;
274 }
275
atmel_pcm_open(struct snd_soc_component * component,struct snd_pcm_substream * substream)276 static int atmel_pcm_open(struct snd_soc_component *component,
277 struct snd_pcm_substream *substream)
278 {
279 struct snd_pcm_runtime *runtime = substream->runtime;
280 struct atmel_runtime_data *prtd;
281 int ret = 0;
282
283 snd_soc_set_runtime_hwparams(substream, &atmel_pcm_hardware);
284
285 /* ensure that buffer size is a multiple of period size */
286 ret = snd_pcm_hw_constraint_integer(runtime,
287 SNDRV_PCM_HW_PARAM_PERIODS);
288 if (ret < 0)
289 goto out;
290
291 prtd = kzalloc(sizeof(struct atmel_runtime_data), GFP_KERNEL);
292 if (prtd == NULL) {
293 ret = -ENOMEM;
294 goto out;
295 }
296 runtime->private_data = prtd;
297
298 out:
299 return ret;
300 }
301
atmel_pcm_close(struct snd_soc_component * component,struct snd_pcm_substream * substream)302 static int atmel_pcm_close(struct snd_soc_component *component,
303 struct snd_pcm_substream *substream)
304 {
305 struct atmel_runtime_data *prtd = substream->runtime->private_data;
306
307 kfree(prtd);
308 return 0;
309 }
310
311 static const struct snd_soc_component_driver atmel_soc_platform = {
312 .open = atmel_pcm_open,
313 .close = atmel_pcm_close,
314 .hw_params = atmel_pcm_hw_params,
315 .hw_free = atmel_pcm_hw_free,
316 .prepare = atmel_pcm_prepare,
317 .trigger = atmel_pcm_trigger,
318 .pointer = atmel_pcm_pointer,
319 .pcm_construct = atmel_pcm_new,
320 };
321
atmel_pcm_pdc_platform_register(struct device * dev)322 int atmel_pcm_pdc_platform_register(struct device *dev)
323 {
324 return devm_snd_soc_register_component(dev, &atmel_soc_platform,
325 NULL, 0);
326 }
327 EXPORT_SYMBOL(atmel_pcm_pdc_platform_register);
328
329 MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>");
330 MODULE_DESCRIPTION("Atmel PCM module");
331 MODULE_LICENSE("GPL");
332