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From: zonque@gmail.com (Daniel Mack)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 17/20] ASoC: pxa: pxa-pcm-lib: switch over to snd-soc-dmaengine-pcm
Date: Wed,  7 Aug 2013 17:34:06 +0200	[thread overview]
Message-ID: <1375889649-14638-18-git-send-email-zonque@gmail.com> (raw)
In-Reply-To: <1375889649-14638-1-git-send-email-zonque@gmail.com>

This patch removes the old PXA DMA API usage and switches over to
generic functions provided by snd-soc-dmaengine-pcm.

More cleanups may be done on top of this, and some function stubs can
now be removed completetly. However, the intention here was to keep
the transition as small as possible.

Signed-off-by: Daniel Mack <zonque@gmail.com>
---
 include/sound/pxa2xx-lib.h |   1 -
 sound/arm/Kconfig          |   1 +
 sound/arm/pxa2xx-pcm-lib.c | 203 ++++++++-------------------------------------
 sound/arm/pxa2xx-pcm.c     |  12 +--
 sound/arm/pxa2xx-pcm.h     |   3 -
 sound/soc/pxa/pxa2xx-pcm.c |  26 +-----
 6 files changed, 42 insertions(+), 204 deletions(-)

diff --git a/include/sound/pxa2xx-lib.h b/include/sound/pxa2xx-lib.h
index 56e818e..6ef629b 100644
--- a/include/sound/pxa2xx-lib.h
+++ b/include/sound/pxa2xx-lib.h
@@ -12,7 +12,6 @@ extern int __pxa2xx_pcm_hw_free(struct snd_pcm_substream *substream);
 extern int pxa2xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd);
 extern snd_pcm_uframes_t pxa2xx_pcm_pointer(struct snd_pcm_substream *substream);
 extern int __pxa2xx_pcm_prepare(struct snd_pcm_substream *substream);
-extern void pxa2xx_pcm_dma_irq(int dma_ch, void *dev_id);
 extern int __pxa2xx_pcm_open(struct snd_pcm_substream *substream);
 extern int __pxa2xx_pcm_close(struct snd_pcm_substream *substream);
 extern int pxa2xx_pcm_mmap(struct snd_pcm_substream *substream,
diff --git a/sound/arm/Kconfig b/sound/arm/Kconfig
index 885683a..c7a872c 100644
--- a/sound/arm/Kconfig
+++ b/sound/arm/Kconfig
@@ -24,6 +24,7 @@ config SND_PXA2XX_PCM
 config SND_PXA2XX_LIB
 	tristate
 	select SND_AC97_CODEC if SND_PXA2XX_LIB_AC97
+	select SND_SOC_DMAENGINE_PCM
 
 config SND_PXA2XX_LIB_AC97
 	bool
diff --git a/sound/arm/pxa2xx-pcm-lib.c b/sound/arm/pxa2xx-pcm-lib.c
index a61d7a9..8471e48 100644
--- a/sound/arm/pxa2xx-pcm-lib.c
+++ b/sound/arm/pxa2xx-pcm-lib.c
@@ -8,6 +8,7 @@
 #include <linux/module.h>
 #include <linux/dma-mapping.h>
 #include <linux/dmaengine.h>
+#include <linux/dma/mmp-pdma.h>
 
 #include <sound/core.h>
 #include <sound/pcm.h>
@@ -15,8 +16,6 @@
 #include <sound/pxa2xx-lib.h>
 #include <sound/dmaengine_pcm.h>
 
-#include <mach/dma.h>
-
 #include "pxa2xx-pcm.h"
 
 static const struct snd_pcm_hardware pxa2xx_pcm_hardware = {
@@ -31,7 +30,7 @@ static const struct snd_pcm_hardware pxa2xx_pcm_hardware = {
 	.period_bytes_min	= 32,
 	.period_bytes_max	= 8192 - 32,
 	.periods_min		= 1,
-	.periods_max		= PAGE_SIZE/sizeof(pxa_dma_desc),
+	.periods_max		= 256,
 	.buffer_bytes_max	= 128 * 1024,
 	.fifo_size		= 32,
 };
@@ -39,65 +38,29 @@ static const struct snd_pcm_hardware pxa2xx_pcm_hardware = {
 int __pxa2xx_pcm_hw_params(struct snd_pcm_substream *substream,
 				struct snd_pcm_hw_params *params)
 {
-	struct snd_pcm_runtime *runtime = substream->runtime;
-	struct pxa2xx_runtime_data *rtd = runtime->private_data;
-	size_t totsize = params_buffer_bytes(params);
-	size_t period = params_period_bytes(params);
-	pxa_dma_desc *dma_desc;
-	dma_addr_t dma_buff_phys, next_desc_phys;
-	u32 dcmd = DCMD_INCSRCADDR | DCMD_FLOWTRG;
+	struct dma_chan *chan = snd_dmaengine_pcm_get_chan(substream);
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_dmaengine_dai_dma_data *dma_params;
+	struct dma_slave_config config;
+	int ret;
 
-	/* temporary transition hack */
-	switch (rtd->params->addr_width) {
-	case DMA_SLAVE_BUSWIDTH_1_BYTE:
-		dcmd |= DCMD_WIDTH1;
-		break;
-	case DMA_SLAVE_BUSWIDTH_2_BYTES:
-		dcmd |= DCMD_WIDTH2;
-		break;
-	case DMA_SLAVE_BUSWIDTH_4_BYTES:
-		dcmd |= DCMD_WIDTH4;
-		break;
-	default:
-		/* can't happen */
-		break;
-	}
+	dma_params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
+	if (!dma_params)
+		return 0;
 
-	switch (rtd->params->maxburst) {
-	case 8:
-		dcmd |= DCMD_BURST8;
-		break;
-	case 16:
-		dcmd |= DCMD_BURST16;
-		break;
-	case 32:
-		dcmd |= DCMD_BURST32;
-		break;
-	}
+	ret = snd_hwparams_to_dma_slave_config(substream, params, &config);
+	if (ret)
+		return ret;
 
-	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
-	runtime->dma_bytes = totsize;
+	snd_dmaengine_pcm_set_config_from_dai_data(substream,
+			snd_soc_dai_get_dma_data(rtd->cpu_dai, substream),
+			&config);
 
-	dma_desc = rtd->dma_desc_array;
-	next_desc_phys = rtd->dma_desc_array_phys;
-	dma_buff_phys = runtime->dma_addr;
-	do {
-		next_desc_phys += sizeof(pxa_dma_desc);
-		dma_desc->ddadr = next_desc_phys;
-		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
-			dma_desc->dsadr = dma_buff_phys;
-			dma_desc->dtadr = rtd->params->addr;
-		} else {
-			dma_desc->dsadr = rtd->params->addr;
-			dma_desc->dtadr = dma_buff_phys;
-		}
-		if (period > totsize)
-			period = totsize;
-		dma_desc->dcmd = dcmd | period | DCMD_ENDIRQEN;
-		dma_desc++;
-		dma_buff_phys += period;
-	} while (totsize -= period);
-	dma_desc[-1].ddadr = rtd->dma_desc_array_phys;
+	ret = dmaengine_slave_config(chan, &config);
+	if (ret)
+		return ret;
+
+	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 
 	return 0;
 }
@@ -105,13 +68,6 @@ EXPORT_SYMBOL(__pxa2xx_pcm_hw_params);
 
 int __pxa2xx_pcm_hw_free(struct snd_pcm_substream *substream)
 {
-	struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
-
-	if (rtd && rtd->params && rtd->params->filter_data) {
-		unsigned long req = *(unsigned long *) rtd->params->filter_data;
-		DRCMR(req) = 0;
-	}
-
 	snd_pcm_set_runtime_buffer(substream, NULL);
 	return 0;
 }
@@ -119,102 +75,36 @@ EXPORT_SYMBOL(__pxa2xx_pcm_hw_free);
 
 int pxa2xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 {
-	struct pxa2xx_runtime_data *prtd = substream->runtime->private_data;
-	int ret = 0;
-
-	switch (cmd) {
-	case SNDRV_PCM_TRIGGER_START:
-		DDADR(prtd->dma_ch) = prtd->dma_desc_array_phys;
-		DCSR(prtd->dma_ch) = DCSR_RUN;
-		break;
-
-	case SNDRV_PCM_TRIGGER_STOP:
-	case SNDRV_PCM_TRIGGER_SUSPEND:
-	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
-		DCSR(prtd->dma_ch) &= ~DCSR_RUN;
-		break;
-
-	case SNDRV_PCM_TRIGGER_RESUME:
-		DCSR(prtd->dma_ch) |= DCSR_RUN;
-		break;
-	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
-		DDADR(prtd->dma_ch) = prtd->dma_desc_array_phys;
-		DCSR(prtd->dma_ch) |= DCSR_RUN;
-		break;
-
-	default:
-		ret = -EINVAL;
-	}
-
-	return ret;
+	return snd_dmaengine_pcm_trigger(substream, cmd);
 }
 EXPORT_SYMBOL(pxa2xx_pcm_trigger);
 
 snd_pcm_uframes_t
 pxa2xx_pcm_pointer(struct snd_pcm_substream *substream)
 {
-	struct snd_pcm_runtime *runtime = substream->runtime;
-	struct pxa2xx_runtime_data *prtd = runtime->private_data;
-
-	dma_addr_t ptr = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
-			 DSADR(prtd->dma_ch) : DTADR(prtd->dma_ch);
-	snd_pcm_uframes_t x = bytes_to_frames(runtime, ptr - runtime->dma_addr);
-
-	if (x == runtime->buffer_size)
-		x = 0;
-	return x;
+	return snd_dmaengine_pcm_pointer(substream);
 }
 EXPORT_SYMBOL(pxa2xx_pcm_pointer);
 
 int __pxa2xx_pcm_prepare(struct snd_pcm_substream *substream)
 {
-	struct pxa2xx_runtime_data *prtd = substream->runtime->private_data;
-	unsigned long req;
-
-	if (!prtd || !prtd->params)
-		return 0;
-
-	if (prtd->dma_ch == -1)
-		return -EINVAL;
-
-	DCSR(prtd->dma_ch) &= ~DCSR_RUN;
-	DCSR(prtd->dma_ch) = 0;
-	DCMD(prtd->dma_ch) = 0;
-	req = *(unsigned long *) prtd->params->filter_data;
-	DRCMR(req) = prtd->dma_ch | DRCMR_MAPVLD;
-
 	return 0;
 }
 EXPORT_SYMBOL(__pxa2xx_pcm_prepare);
 
-void pxa2xx_pcm_dma_irq(int dma_ch, void *dev_id)
-{
-	struct snd_pcm_substream *substream = dev_id;
-	int dcsr;
-
-	dcsr = DCSR(dma_ch);
-	DCSR(dma_ch) = dcsr & ~DCSR_STOPIRQEN;
-
-	if (dcsr & DCSR_ENDINTR) {
-		snd_pcm_period_elapsed(substream);
-	} else {
-		printk(KERN_ERR "DMA error on channel %d (DCSR=%#x)\n",
-			dma_ch, dcsr);
-		snd_pcm_stream_lock(substream);
-		snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
-		snd_pcm_stream_unlock(substream);
-	}
-}
-EXPORT_SYMBOL(pxa2xx_pcm_dma_irq);
-
 int __pxa2xx_pcm_open(struct snd_pcm_substream *substream)
 {
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
 	struct snd_pcm_runtime *runtime = substream->runtime;
-	struct pxa2xx_runtime_data *rtd;
+	struct snd_dmaengine_dai_dma_data *dma_params;
 	int ret;
 
 	runtime->hw = pxa2xx_pcm_hardware;
 
+	dma_params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
+	if (!dma_params)
+		return 0;
+
 	/*
 	 * For mysterious reasons (and despite what the manual says)
 	 * playback samples are lost if the DMA count is not a multiple
@@ -223,48 +113,27 @@ int __pxa2xx_pcm_open(struct snd_pcm_substream *substream)
 	ret = snd_pcm_hw_constraint_step(runtime, 0,
 		SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 32);
 	if (ret)
-		goto out;
+		return ret;
 
 	ret = snd_pcm_hw_constraint_step(runtime, 0,
 		SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 32);
 	if (ret)
-		goto out;
+		return ret;
 
 	ret = snd_pcm_hw_constraint_integer(runtime,
 					    SNDRV_PCM_HW_PARAM_PERIODS);
 	if (ret < 0)
-		goto out;
-
-	ret = -ENOMEM;
-	rtd = kzalloc(sizeof(*rtd), GFP_KERNEL);
-	if (!rtd)
-		goto out;
-	rtd->dma_desc_array =
-		dma_alloc_writecombine(substream->pcm->card->dev, PAGE_SIZE,
-				       &rtd->dma_desc_array_phys, GFP_KERNEL);
-	if (!rtd->dma_desc_array)
-		goto err1;
+		return ret;
 
-	rtd->dma_ch = -1;
-	runtime->private_data = rtd;
-	return 0;
-
- err1:
-	kfree(rtd);
- out:
-	return ret;
+	return snd_dmaengine_pcm_open_request_chan(substream,
+					mmp_pdma_filter_fn,
+					dma_params->filter_data);
 }
 EXPORT_SYMBOL(__pxa2xx_pcm_open);
 
 int __pxa2xx_pcm_close(struct snd_pcm_substream *substream)
 {
-	struct snd_pcm_runtime *runtime = substream->runtime;
-	struct pxa2xx_runtime_data *rtd = runtime->private_data;
-
-	dma_free_writecombine(substream->pcm->card->dev, PAGE_SIZE,
-			      rtd->dma_desc_array, rtd->dma_desc_array_phys);
-	kfree(rtd);
-	return 0;
+	return snd_dmaengine_pcm_close_release_chan(substream);
 }
 EXPORT_SYMBOL(__pxa2xx_pcm_close);
 
diff --git a/sound/arm/pxa2xx-pcm.c b/sound/arm/pxa2xx-pcm.c
index 69a2455..51be1d4 100644
--- a/sound/arm/pxa2xx-pcm.c
+++ b/sound/arm/pxa2xx-pcm.c
@@ -43,17 +43,13 @@ static int pxa2xx_pcm_open(struct snd_pcm_substream *substream)
 
 	rtd->params = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
 		      client->playback_params : client->capture_params;
-	ret = pxa_request_dma("dma", DMA_PRIO_LOW,
-			      pxa2xx_pcm_dma_irq, substream);
-	if (ret < 0)
-		goto err2;
-	rtd->dma_ch = ret;
 
 	ret = client->startup(substream);
 	if (!ret)
-		goto out;
+		goto err2;
+
+	return 0;
 
-	pxa_free_dma(rtd->dma_ch);
  err2:
 	__pxa2xx_pcm_close(substream);
  out:
@@ -63,9 +59,7 @@ static int pxa2xx_pcm_open(struct snd_pcm_substream *substream)
 static int pxa2xx_pcm_close(struct snd_pcm_substream *substream)
 {
 	struct pxa2xx_pcm_client *client = substream->private_data;
-	struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
 
-	pxa_free_dma(rtd->dma_ch);
 	client->shutdown(substream);
 
 	return __pxa2xx_pcm_close(substream);
diff --git a/sound/arm/pxa2xx-pcm.h b/sound/arm/pxa2xx-pcm.h
index 2a8fc08..8fa2b7c 100644
--- a/sound/arm/pxa2xx-pcm.h
+++ b/sound/arm/pxa2xx-pcm.h
@@ -9,13 +9,10 @@
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
-#include <mach/dma.h>
 
 struct pxa2xx_runtime_data {
 	int dma_ch;
 	struct snd_dmaengine_dai_dma_data *params;
-	pxa_dma_desc *dma_desc_array;
-	dma_addr_t dma_desc_array_phys;
 };
 
 struct pxa2xx_pcm_client {
diff --git a/sound/soc/pxa/pxa2xx-pcm.c b/sound/soc/pxa/pxa2xx-pcm.c
index 806da27..bb44928 100644
--- a/sound/soc/pxa/pxa2xx-pcm.c
+++ b/sound/soc/pxa/pxa2xx-pcm.c
@@ -29,7 +29,6 @@ static int pxa2xx_pcm_hw_params(struct snd_pcm_substream *substream,
 	struct pxa2xx_runtime_data *prtd = runtime->private_data;
 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
 	struct snd_dmaengine_dai_dma_data *dma;
-	int ret;
 
 	dma = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 
@@ -38,24 +37,7 @@ static int pxa2xx_pcm_hw_params(struct snd_pcm_substream *substream,
 	if (!dma)
 		return 0;
 
-	/* this may get called several times by oss emulation
-	 * with different params */
-	if (prtd->params == NULL) {
-		prtd->params = dma;
-		ret = pxa_request_dma("name", DMA_PRIO_LOW,
-			      pxa2xx_pcm_dma_irq, substream);
-		if (ret < 0)
-			return ret;
-		prtd->dma_ch = ret;
-	} else if (prtd->params != dma) {
-		pxa_free_dma(prtd->dma_ch);
-		prtd->params = dma;
-		ret = pxa_request_dma("name", DMA_PRIO_LOW,
-			      pxa2xx_pcm_dma_irq, substream);
-		if (ret < 0)
-			return ret;
-		prtd->dma_ch = ret;
-	}
+	prtd->params = dma;
 
 	return __pxa2xx_pcm_hw_params(substream, params);
 }
@@ -66,11 +48,7 @@ static int pxa2xx_pcm_hw_free(struct snd_pcm_substream *substream)
 
 	__pxa2xx_pcm_hw_free(substream);
 
-	if (prtd->dma_ch >= 0) {
-		pxa_free_dma(prtd->dma_ch);
-		prtd->dma_ch = -1;
-		prtd->params = NULL;
-	}
+	prtd->params = NULL;
 
 	return 0;
 }
-- 
1.8.3.1

  parent reply	other threads:[~2013-08-07 15:34 UTC|newest]

Thread overview: 63+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-08-07 15:33 [PATCH 00/20] ARM: pxa: move core and drivers to dmaengine Daniel Mack
2013-08-07 15:33 ` [PATCH 01/20] mtd: pxa3xx-nand: replace pxa_request_dma with dmaengine Daniel Mack
2013-08-07 17:46   ` Ezequiel Garcia
2013-08-08  6:42     ` Daniel Mack
2013-08-08 10:12       ` Ezequiel Garcia
2013-08-08 10:14         ` Daniel Mack
2013-08-07 15:33 ` [PATCH 02/20] mtd: pxa3xx-nand: use mmp_pdma_filter_fn and dma_request_slave_channel_compat Daniel Mack
2013-08-07 15:33 ` [PATCH 03/20] ARM: pxa: ssp: add shortcut for &pdev->dev Daniel Mack
2013-08-08  7:32   ` Brian Norris
2013-08-08  7:52     ` Artem Bityutskiy
2013-08-08  8:20       ` Daniel Mack
2013-08-07 15:33 ` [PATCH 04/20] ARM: pxa: ssp: add DT bindings Daniel Mack
2013-08-07 15:54   ` Arnd Bergmann
2013-08-07 15:33 ` [PATCH 05/20] ARM: pxa: ssp: use devm_ functions Daniel Mack
2013-08-07 15:33 ` [PATCH 06/20] tty: serial: pxa: remove old cruft Daniel Mack
2013-08-12  8:19   ` Daniel Mack
2013-08-12 18:08     ` Greg KH
2013-08-07 15:33 ` [PATCH 07/20] spi: spi-pxa2xx: remove legacy PXA DMA bits Daniel Mack
2013-08-07 15:55   ` Mark Brown
2013-08-07 15:59     ` Daniel Mack
2013-08-07 16:41       ` Mark Brown
2013-08-07 15:33 ` [PATCH 08/20] mmc: host: pxamci: switch over to dmaengine use Daniel Mack
2014-10-15 18:32   ` Vasily Khoruzhick
2014-10-16 17:57     ` Vasily Khoruzhick
2013-08-07 15:33 ` [PATCH 09/20] ata: pdata_pxa: migrate over to dmaengine usage Daniel Mack
2013-08-07 15:59   ` Arnd Bergmann
2013-08-07 15:33 ` [PATCH 10/20] net: irda: pxaficp_ir: switch to dmaengine Daniel Mack
2013-08-07 15:34 ` [PATCH 11/20] net: smc91x.c: switch to generic buf-to-buf DMA offload Daniel Mack
2013-08-07 15:34 ` [PATCH 12/20] net: smc911x.c: switch to dmaengine API Daniel Mack
2013-08-07 15:34 ` [PATCH 13/20] ASoC: pxa: pxa-ssp: add DT bindings Daniel Mack
2013-08-07 16:40   ` Mark Brown
2013-08-08  9:39     ` Daniel Mack
2013-08-08 13:20       ` Mark Brown
2013-08-09 13:03         ` Daniel Mack
2013-08-07 15:34 ` [PATCH 14/20] ASoC: pxa: use snd_dmaengine_dai_dma_data Daniel Mack
2013-08-07 15:57   ` Mark Brown
2013-08-07 15:34 ` [PATCH 15/20] ASoC: pxa: pxa-ssp: set dma filter data from startup hook Daniel Mack
2013-08-07 15:58   ` Mark Brown
2013-08-07 15:34 ` [PATCH 16/20] ASoC: pxa: add DT bindings for pxa2xx-pcm Daniel Mack
2013-08-07 16:06   ` Mark Brown
2013-08-07 15:34 ` Daniel Mack [this message]
2013-08-07 16:07   ` [PATCH 17/20] ASoC: pxa: pxa-pcm-lib: switch over to snd-soc-dmaengine-pcm Mark Brown
2013-08-07 16:10     ` Daniel Mack
2013-08-07 16:32       ` Mark Brown
2013-08-08  8:18         ` Daniel Mack
2013-08-08  8:44           ` Lars-Peter Clausen
2013-08-08  9:03             ` Daniel Mack
2013-08-08  9:36               ` Mark Brown
2013-08-08  9:43                 ` Daniel Mack
2013-08-08 10:35                   ` Mark Brown
2013-08-08 10:39                     ` Daniel Mack
2013-08-08 11:03                       ` Mark Brown
2013-08-08 10:25                 ` Russell King - ARM Linux
2013-08-07 15:34 ` [PATCH 18/20] ARM: pxa: register static mmp_pdma device Daniel Mack
2013-08-07 15:34 ` [PATCH 19/20] ARM: mmp: " Daniel Mack
2013-08-07 15:34 ` [PATCH 20/20] ARM: pxa: remove old DMA implementation Daniel Mack
2013-08-07 16:08 ` [PATCH 00/20] ARM: pxa: move core and drivers to dmaengine Arnd Bergmann
2013-08-09 22:50 ` Robert Jarzmik
2013-08-10 10:56   ` Daniel Mack
2013-08-11 20:05     ` Robert Jarzmik
2013-08-14 10:00     ` Vinod Koul
2013-08-15 15:22       ` Robert Jarzmik
2013-08-15 15:30         ` Daniel Mack

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