2 * atmel-pcm.c -- ALSA PCM interface for the Atmel atmel SoC.
4 * Copyright (C) 2005 SAN People
5 * Copyright (C) 2008 Atmel
7 * Authors: Sedji Gaouaou <sedji.gaouaou@atmel.com>
9 * Based on at91-pcm. by:
10 * Frank Mandarino <fmandarino@endrelia.com>
11 * Copyright 2006 Endrelia Technologies Inc.
13 * Based on pxa2xx-pcm.c by:
15 * Author: Nicolas Pitre
16 * Created: Nov 30, 2004
17 * Copyright: (C) 2004 MontaVista Software, Inc.
19 * This program is free software; you can redistribute it and/or modify
20 * it under the terms of the GNU General Public License as published by
21 * the Free Software Foundation; either version 2 of the License, or
22 * (at your option) any later version.
24 * This program is distributed in the hope that it will be useful,
25 * but WITHOUT ANY WARRANTY; without even the implied warranty of
26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27 * GNU General Public License for more details.
29 * You should have received a copy of the GNU General Public License
30 * along with this program; if not, write to the Free Software
31 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
34 #include <linux/module.h>
35 #include <linux/init.h>
36 #include <linux/platform_device.h>
37 #include <linux/slab.h>
38 #include <linux/dma-mapping.h>
39 #include <linux/atmel_pdc.h>
40 #include <linux/atmel-ssc.h>
42 #include <sound/core.h>
43 #include <sound/pcm.h>
44 #include <sound/pcm_params.h>
45 #include <sound/soc.h>
47 #include "atmel-pcm.h"
50 /*--------------------------------------------------------------------------*\
52 \*--------------------------------------------------------------------------*/
53 /* TODO: These values were taken from the AT91 platform driver, check
54 * them against real values for AT32
56 static const struct snd_pcm_hardware atmel_pcm_hardware = {
57 .info = SNDRV_PCM_INFO_MMAP |
58 SNDRV_PCM_INFO_MMAP_VALID |
59 SNDRV_PCM_INFO_INTERLEAVED |
61 .period_bytes_min = 32,
62 .period_bytes_max = 8192,
65 .buffer_bytes_max = ATMEL_SSC_DMABUF_SIZE,
69 /*--------------------------------------------------------------------------*\
71 \*--------------------------------------------------------------------------*/
72 struct atmel_runtime_data {
73 struct atmel_pcm_dma_params *params;
74 dma_addr_t dma_buffer; /* physical address of dma buffer */
75 dma_addr_t dma_buffer_end; /* first address beyond DMA buffer */
78 dma_addr_t period_ptr; /* physical address of next period */
80 /* PDC register save */
87 /*--------------------------------------------------------------------------*\
89 \*--------------------------------------------------------------------------*/
90 static void atmel_pcm_dma_irq(u32 ssc_sr,
91 struct snd_pcm_substream *substream)
93 struct atmel_runtime_data *prtd = substream->runtime->private_data;
94 struct atmel_pcm_dma_params *params = prtd->params;
99 if (ssc_sr & params->mask->ssc_endbuf) {
100 pr_warn("atmel-pcm: buffer %s on %s (SSC_SR=%#x, count=%d)\n",
101 substream->stream == SNDRV_PCM_STREAM_PLAYBACK
102 ? "underrun" : "overrun",
103 params->name, ssc_sr, count);
105 /* re-start the PDC */
106 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
107 params->mask->pdc_disable);
108 prtd->period_ptr += prtd->period_size;
109 if (prtd->period_ptr >= prtd->dma_buffer_end)
110 prtd->period_ptr = prtd->dma_buffer;
112 ssc_writex(params->ssc->regs, params->pdc->xpr,
114 ssc_writex(params->ssc->regs, params->pdc->xcr,
115 prtd->period_size / params->pdc_xfer_size);
116 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
117 params->mask->pdc_enable);
120 if (ssc_sr & params->mask->ssc_endx) {
121 /* Load the PDC next pointer and counter registers */
122 prtd->period_ptr += prtd->period_size;
123 if (prtd->period_ptr >= prtd->dma_buffer_end)
124 prtd->period_ptr = prtd->dma_buffer;
126 ssc_writex(params->ssc->regs, params->pdc->xnpr,
128 ssc_writex(params->ssc->regs, params->pdc->xncr,
129 prtd->period_size / params->pdc_xfer_size);
132 snd_pcm_period_elapsed(substream);
136 /*--------------------------------------------------------------------------*\
138 \*--------------------------------------------------------------------------*/
139 static int atmel_pcm_hw_params(struct snd_pcm_substream *substream,
140 struct snd_pcm_hw_params *params)
142 struct snd_pcm_runtime *runtime = substream->runtime;
143 struct atmel_runtime_data *prtd = runtime->private_data;
144 struct snd_soc_pcm_runtime *rtd = substream->private_data;
146 /* this may get called several times by oss emulation
147 * with different params */
149 snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
150 runtime->dma_bytes = params_buffer_bytes(params);
152 prtd->params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
153 prtd->params->dma_intr_handler = atmel_pcm_dma_irq;
155 prtd->dma_buffer = runtime->dma_addr;
156 prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes;
157 prtd->period_size = params_period_bytes(params);
159 pr_debug("atmel-pcm: "
160 "hw_params: DMA for %s initialized "
161 "(dma_bytes=%zu, period_size=%zu)\n",
168 static int atmel_pcm_hw_free(struct snd_pcm_substream *substream)
170 struct atmel_runtime_data *prtd = substream->runtime->private_data;
171 struct atmel_pcm_dma_params *params = prtd->params;
173 if (params != NULL) {
174 ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
175 params->mask->pdc_disable);
176 prtd->params->dma_intr_handler = NULL;
182 static int atmel_pcm_prepare(struct snd_pcm_substream *substream)
184 struct atmel_runtime_data *prtd = substream->runtime->private_data;
185 struct atmel_pcm_dma_params *params = prtd->params;
187 ssc_writex(params->ssc->regs, SSC_IDR,
188 params->mask->ssc_endx | params->mask->ssc_endbuf);
189 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
190 params->mask->pdc_disable);
194 static int atmel_pcm_trigger(struct snd_pcm_substream *substream,
197 struct snd_pcm_runtime *rtd = substream->runtime;
198 struct atmel_runtime_data *prtd = rtd->private_data;
199 struct atmel_pcm_dma_params *params = prtd->params;
202 pr_debug("atmel-pcm:buffer_size = %ld,"
203 "dma_area = %p, dma_bytes = %zu\n",
204 rtd->buffer_size, rtd->dma_area, rtd->dma_bytes);
207 case SNDRV_PCM_TRIGGER_START:
208 prtd->period_ptr = prtd->dma_buffer;
210 ssc_writex(params->ssc->regs, params->pdc->xpr,
212 ssc_writex(params->ssc->regs, params->pdc->xcr,
213 prtd->period_size / params->pdc_xfer_size);
215 prtd->period_ptr += prtd->period_size;
216 ssc_writex(params->ssc->regs, params->pdc->xnpr,
218 ssc_writex(params->ssc->regs, params->pdc->xncr,
219 prtd->period_size / params->pdc_xfer_size);
221 pr_debug("atmel-pcm: trigger: "
222 "period_ptr=%lx, xpr=%u, "
223 "xcr=%u, xnpr=%u, xncr=%u\n",
224 (unsigned long)prtd->period_ptr,
225 ssc_readx(params->ssc->regs, params->pdc->xpr),
226 ssc_readx(params->ssc->regs, params->pdc->xcr),
227 ssc_readx(params->ssc->regs, params->pdc->xnpr),
228 ssc_readx(params->ssc->regs, params->pdc->xncr));
230 ssc_writex(params->ssc->regs, SSC_IER,
231 params->mask->ssc_endx | params->mask->ssc_endbuf);
232 ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
233 params->mask->pdc_enable);
235 pr_debug("sr=%u imr=%u\n",
236 ssc_readx(params->ssc->regs, SSC_SR),
237 ssc_readx(params->ssc->regs, SSC_IER));
238 break; /* SNDRV_PCM_TRIGGER_START */
240 case SNDRV_PCM_TRIGGER_STOP:
241 case SNDRV_PCM_TRIGGER_SUSPEND:
242 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
243 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
244 params->mask->pdc_disable);
247 case SNDRV_PCM_TRIGGER_RESUME:
248 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
249 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
250 params->mask->pdc_enable);
260 static snd_pcm_uframes_t atmel_pcm_pointer(
261 struct snd_pcm_substream *substream)
263 struct snd_pcm_runtime *runtime = substream->runtime;
264 struct atmel_runtime_data *prtd = runtime->private_data;
265 struct atmel_pcm_dma_params *params = prtd->params;
269 ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr);
270 x = bytes_to_frames(runtime, ptr - prtd->dma_buffer);
272 if (x == runtime->buffer_size)
278 static int atmel_pcm_open(struct snd_pcm_substream *substream)
280 struct snd_pcm_runtime *runtime = substream->runtime;
281 struct atmel_runtime_data *prtd;
284 snd_soc_set_runtime_hwparams(substream, &atmel_pcm_hardware);
286 /* ensure that buffer size is a multiple of period size */
287 ret = snd_pcm_hw_constraint_integer(runtime,
288 SNDRV_PCM_HW_PARAM_PERIODS);
292 prtd = kzalloc(sizeof(struct atmel_runtime_data), GFP_KERNEL);
297 runtime->private_data = prtd;
303 static int atmel_pcm_close(struct snd_pcm_substream *substream)
305 struct atmel_runtime_data *prtd = substream->runtime->private_data;
311 static struct snd_pcm_ops atmel_pcm_ops = {
312 .open = atmel_pcm_open,
313 .close = atmel_pcm_close,
314 .ioctl = snd_pcm_lib_ioctl,
315 .hw_params = atmel_pcm_hw_params,
316 .hw_free = atmel_pcm_hw_free,
317 .prepare = atmel_pcm_prepare,
318 .trigger = atmel_pcm_trigger,
319 .pointer = atmel_pcm_pointer,
320 .mmap = atmel_pcm_mmap,
324 /*--------------------------------------------------------------------------*\
325 * ASoC platform driver
326 \*--------------------------------------------------------------------------*/
328 static int atmel_pcm_suspend(struct snd_soc_dai *dai)
330 struct snd_pcm_runtime *runtime = dai->runtime;
331 struct atmel_runtime_data *prtd;
332 struct atmel_pcm_dma_params *params;
337 prtd = runtime->private_data;
338 params = prtd->params;
340 /* disable the PDC and save the PDC registers */
342 ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_disable);
344 prtd->pdc_xpr_save = ssc_readx(params->ssc->regs, params->pdc->xpr);
345 prtd->pdc_xcr_save = ssc_readx(params->ssc->regs, params->pdc->xcr);
346 prtd->pdc_xnpr_save = ssc_readx(params->ssc->regs, params->pdc->xnpr);
347 prtd->pdc_xncr_save = ssc_readx(params->ssc->regs, params->pdc->xncr);
352 static int atmel_pcm_resume(struct snd_soc_dai *dai)
354 struct snd_pcm_runtime *runtime = dai->runtime;
355 struct atmel_runtime_data *prtd;
356 struct atmel_pcm_dma_params *params;
361 prtd = runtime->private_data;
362 params = prtd->params;
364 /* restore the PDC registers and enable the PDC */
365 ssc_writex(params->ssc->regs, params->pdc->xpr, prtd->pdc_xpr_save);
366 ssc_writex(params->ssc->regs, params->pdc->xcr, prtd->pdc_xcr_save);
367 ssc_writex(params->ssc->regs, params->pdc->xnpr, prtd->pdc_xnpr_save);
368 ssc_writex(params->ssc->regs, params->pdc->xncr, prtd->pdc_xncr_save);
370 ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_enable);
374 #define atmel_pcm_suspend NULL
375 #define atmel_pcm_resume NULL
378 static struct snd_soc_platform_driver atmel_soc_platform = {
379 .ops = &atmel_pcm_ops,
380 .pcm_new = atmel_pcm_new,
381 .pcm_free = atmel_pcm_free,
382 .suspend = atmel_pcm_suspend,
383 .resume = atmel_pcm_resume,
386 int atmel_pcm_pdc_platform_register(struct device *dev)
388 return snd_soc_register_platform(dev, &atmel_soc_platform);
390 EXPORT_SYMBOL(atmel_pcm_pdc_platform_register);
392 void atmel_pcm_pdc_platform_unregister(struct device *dev)
394 snd_soc_unregister_platform(dev);
396 EXPORT_SYMBOL(atmel_pcm_pdc_platform_unregister);
398 MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>");
399 MODULE_DESCRIPTION("Atmel PCM module");
400 MODULE_LICENSE("GPL");