[PATCH] ARM: s3c24xx: Add dma_slave_map for s3c2440 devices

[PATCH] ARM: s3c24xx: Add dma_slave_map for s3c2440 devices

[Sam Van Den Berge]

This patch updates the s3c24xx dma driver to be able to pass a
dma_slave_map array via the platform data. This is needed to
be able to use the new, simpler dmaengine API [1].
I used the virtual DMA channels as a parameter for the dma_filter
function. By doing that, I could reuse the existing filter function in
drivers/dma/s3c24xx-dma.c.

I have tested this on my mini2440 board with the audio driver.
(I first applied the audio fixes from Sylwester Nawrocki [2])
According to my observations, dma_request_slave_channel in the
function dmaengine_pcm_new in the file
sound/soc/soc-generic-dmaengine-pcm.c now returns a valid DMA channel
whereas before no DMA channel was returned at that point.

Entries for DMACH_XD0, DMACH_XD1 and DMACH_TIMER are missing because I
don't realy know which driver to use for these.

[1]
http://lists.infradead.org/pipermail/linux-arm-kernel/2015-December/393635.html
[2] http://www.spinics.net/lists/arm-kernel/msg521918.html

Signed-off-by: Sam Van Den Berge <sam.van.den.berge@telenet.be>
---
 arch/arm/mach-s3c24xx/common.c            | 36 +++++++++++++++++++++++++++++++
 drivers/dma/s3c24xx-dma.c                 |  3 +++
 include/linux/platform_data/dma-s3c24xx.h |  6 ++++++
 3 files changed, 45 insertions(+)

diff --git a/arch/arm/mach-s3c24xx/common.c b/arch/arm/mach-s3c24xx/common.c
index fe7485d..d5cadef 100644
--- a/arch/arm/mach-s3c24xx/common.c
+++ b/arch/arm/mach-s3c24xx/common.c
@@ -33,6 +33,7 @@
 #include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/platform_data/dma-s3c24xx.h>
+#include <linux/dmaengine.h>
 
 #include <mach/hardware.h>
 #include <mach/regs-clock.h>
@@ -445,10 +446,45 @@ static struct s3c24xx_dma_channel s3c2440_dma_channels[DMACH_MAX] = {
 	[DMACH_USB_EP4] = { S3C24XX_DMA_APB, true, S3C24XX_DMA_CHANREQ(4, 3), },
 };
 
+static const struct dma_slave_map s3c2440_dma_slave_map[] = {
+	/* TODO: DMACH_XD0 */
+	/* TODO: DMACH_XD1 */
+	{ "3c2440-sdi", "rx", (void *)DMACH_SDI },
+	{ "3c2440-sdi", "tx", (void *)DMACH_SDI },
+	{ "s3c2410-spi.0", "rx", (void *)DMACH_SPI0 },
+	{ "s3c2410-spi.0", "tx", (void *)DMACH_SPI0 },
+	{ "s3c2410-spi.1", "rx", (void *)DMACH_SPI1 },
+	{ "s3c2410-spi.1", "tx", (void *)DMACH_SPI1 },
+	{ "s3c2440-uart.0", "rx", (void *)DMACH_UART0 },
+	{ "s3c2440-uart.0", "tx", (void *)DMACH_UART0 },
+	{ "s3c2440-uart.1", "rx", (void *)DMACH_UART1 },
+	{ "s3c2440-uart.1", "tx", (void *)DMACH_UART1 },
+	{ "s3c2440-uart.2", "rx", (void *)DMACH_UART2 },
+	{ "s3c2440-uart.2", "tx", (void *)DMACH_UART2 },
+	{ "s3c2440-uart.3", "rx", (void *)DMACH_UART3 },
+	{ "s3c2440-uart.3", "tx", (void *)DMACH_UART3 },
+	/* TODO: DMACH_TIMER */
+	{ "s3c24xx-iis", "rx", (void *)DMACH_I2S_IN },
+	{ "s3c24xx-iis", "tx", (void *)DMACH_I2S_OUT },
+	{ "samsung-ac97", "rx", (void *)DMACH_PCM_IN },
+	{ "samsung-ac97", "tx", (void *)DMACH_PCM_OUT },
+	{ "samsung-ac97", "rx", (void *)DMACH_MIC_IN },
+	{ "s3c-hsudc", "rx0", (void *)DMACH_USB_EP1 },
+	{ "s3c-hsudc", "rx1", (void *)DMACH_USB_EP2 },
+	{ "s3c-hsudc", "rx2", (void *)DMACH_USB_EP3 },
+	{ "s3c-hsudc", "rx3", (void *)DMACH_USB_EP4 },
+	{ "s3c-hsudc", "tx0", (void *)DMACH_USB_EP1 },
+	{ "s3c-hsudc", "tx1", (void *)DMACH_USB_EP2 },
+	{ "s3c-hsudc", "tx2", (void *)DMACH_USB_EP3 },
+	{ "s3c-hsudc", "tx3", (void *)DMACH_USB_EP4 }
+};
+
 static struct s3c24xx_dma_platdata s3c2440_dma_platdata = {
 	.num_phy_channels = 4,
 	.channels = s3c2440_dma_channels,
 	.num_channels = DMACH_MAX,
+	.slave_map = s3c2440_dma_slave_map,
+	.slavecnt = ARRAY_SIZE(s3c2440_dma_slave_map),
 };
 
 struct platform_device s3c2440_device_dma = {
diff --git a/drivers/dma/s3c24xx-dma.c b/drivers/dma/s3c24xx-dma.c
index ce67075..d5c85e7 100644
--- a/drivers/dma/s3c24xx-dma.c
+++ b/drivers/dma/s3c24xx-dma.c
@@ -1301,6 +1301,9 @@ static int s3c24xx_dma_probe(struct platform_device *pdev)
 	s3cdma->slave.device_prep_dma_cyclic = s3c24xx_dma_prep_dma_cyclic;
 	s3cdma->slave.device_config = s3c24xx_dma_set_runtime_config;
 	s3cdma->slave.device_terminate_all = s3c24xx_dma_terminate_all;
+	s3cdma->slave.filter.map = pdata->slave_map;
+	s3cdma->slave.filter.mapcnt = pdata->slavecnt;
+	s3cdma->slave.filter.fn = s3c24xx_dma_filter;
 
 	/* Register as many memcpy channels as there are physical channels */
 	ret = s3c24xx_dma_init_virtual_channels(s3cdma, &s3cdma->memcpy,
diff --git a/include/linux/platform_data/dma-s3c24xx.h b/include/linux/platform_data/dma-s3c24xx.h
index 89ba1b0..4f9aba4 100644
--- a/include/linux/platform_data/dma-s3c24xx.h
+++ b/include/linux/platform_data/dma-s3c24xx.h
@@ -30,16 +30,22 @@ struct s3c24xx_dma_channel {
 	u16 chansel;
 };
 
+struct dma_slave_map;
+
 /**
  * struct s3c24xx_dma_platdata - platform specific settings
  * @num_phy_channels: number of physical channels
  * @channels: array of virtual channel descriptions
  * @num_channels: number of virtual channels
+ * @slave_map: dma slave map matching table
+ * @slavecnt: number of elements in slave_map
  */
 struct s3c24xx_dma_platdata {
 	int num_phy_channels;
 	struct s3c24xx_dma_channel *channels;
 	int num_channels;
+	const struct dma_slave_map *slave_map;
+	int slavecnt;
 };
 
 struct dma_chan;
-- 
1.9.1

Re: [PATCH] ARM: s3c24xx: Add dma_slave_map for s3c2440 devices

[Sylwester Nawrocki]

On 09/14/2016 08:29 PM, Sam Van Den Berge wrote:
> +static const struct dma_slave_map s3c2440_dma_slave_map[] = {
...
> +	{ "3c2440-sdi", "rx", (void *)DMACH_SDI },
> +	{ "3c2440-sdi", "tx", (void *)DMACH_SDI },

The device names seem misspelled here, and looking at what
drivers/mmc/host/s3cmci.c driver does we need just a single common
entry for rx and tx

	{ "s3c2440-sdi", "rx-tx", (void *)DMACH_SDI },

With this fixed feel free to add

Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>

-- 
Thanks,
Sylwester

Re: [PATCH] ARM: s3c24xx: Add dma_slave_map for s3c2440 devices

[Vinod Koul]

On Thu, Sep 15, 2016 at 11:05:12AM +0200, Sylwester Nawrocki wrote:
> On 09/14/2016 08:29 PM, Sam Van Den Berge wrote:
> > +static const struct dma_slave_map s3c2440_dma_slave_map[] = {
> ...
> > +	{ "3c2440-sdi", "rx", (void *)DMACH_SDI },
> > +	{ "3c2440-sdi", "tx", (void *)DMACH_SDI },
> 
> The device names seem misspelled here, and looking at what
> drivers/mmc/host/s3cmci.c driver does we need just a single common
> entry for rx and tx
> 
> 	{ "s3c2440-sdi", "rx-tx", (void *)DMACH_SDI },
> 
> With this fixed feel free to add

And please change the title to dmaengine and NOT arm... I was about ti skip
this!

-- 
~Vinod

Re: [PATCH] ARM: s3c24xx: Add dma_slave_map for s3c2440 devices

[Arnd Bergmann]

On Wednesday, September 14, 2016 8:29:35 PM CEST Sam Van Den Berge wrote:
> This patch updates the s3c24xx dma driver to be able to pass a
> dma_slave_map array via the platform data. This is needed to
> be able to use the new, simpler dmaengine API [1].
> I used the virtual DMA channels as a parameter for the dma_filter
> function. By doing that, I could reuse the existing filter function in
> drivers/dma/s3c24xx-dma.c.
> 
> I have tested this on my mini2440 board with the audio driver.
> (I first applied the audio fixes from Sylwester Nawrocki [2])
> According to my observations, dma_request_slave_channel in the
> function dmaengine_pcm_new in the file
> sound/soc/soc-generic-dmaengine-pcm.c now returns a valid DMA channel
> whereas before no DMA channel was returned at that point.
> 
> Entries for DMACH_XD0, DMACH_XD1 and DMACH_TIMER are missing because I
> don't realy know which driver to use for these.
> 
> [1]
> http://lists.infradead.org/pipermail/linux-arm-kernel/2015-December/393635.html
> [2] http://www.spinics.net/lists/arm-kernel/msg521918.html
> 
> Signed-off-by: Sam Van Den Berge <sam.van.den.berge@telenet.be>
> 

Thanks for doing this, once this is merged we should be able to
change all the drivers that currently use this DMA support
(I think just spi, mmc and audio) over to the new dma_request_chan
function.

The logical follow-up after that would be to unify the slave_map
with the s3c24xx_dma_channel tables, along the lines of

--- a/arch/arm/mach-s3c24xx/common.c
+++ b/arch/arm/mach-s3c24xx/common.c
@@ -475,28 +475,14 @@ static struct resource s3c2443_dma_resource[] = {
 	[6] = DEFINE_RES_IRQ(IRQ_S3C2443_DMA5),
 };
 
-static struct s3c24xx_dma_channel s3c2443_dma_channels[DMACH_MAX] = {
+static struct dma_slave_map s3c2443_dma_channels[] = {
-	[DMACH_XD0] = { S3C24XX_DMA_AHB, true, 17 },
-	[DMACH_XD1] = { S3C24XX_DMA_AHB, true, 18 },
-	[DMACH_SDI] = { S3C24XX_DMA_APB, false, 10 },
-	[DMACH_SPI0_RX] = { S3C24XX_DMA_APB, true, 1 },
-	[DMACH_SPI0_TX] = { S3C24XX_DMA_APB, true, 0 },
-	[DMACH_SPI1_RX] = { S3C24XX_DMA_APB, true, 3 },
-	[DMACH_SPI1_TX] = { S3C24XX_DMA_APB, true, 2 },
+	{ "xd0",	"data",	 S3C_DMA_SLAVE(S3C24XX_DMA_AHB, true,  17) },
+	{ "xd1",	"data",	 S3C_DMA_SLAVE(S3C24XX_DMA_AHB, true,  18) },
+	{ "3c2440-sdi", "data",	 S3C_DMA_SLAVE(S3C24XX_DMA_APB, false, 10) },
+	{ "s3c2410-spi.0", "rx", S3C_DMA_SLAVE(S3C24XX_DMA_APB, true,   1) },
+	{ "s3c2410-spi.0", "tx", S3C_DMA_SLAVE(S3C24XX_DMA_APB, true,   0) },
+	{ "s3c2410-spi.1", "rx", S3C_DMA_SLAVE(S3C24XX_DMA_APB, true,   3) },
+	{ "s3c2410-spi.1", "tx", S3C_DMA_SLAVE(S3C24XX_DMA_APB, true,   2) },
...
 };
 
 static struct s3c24xx_dma_platdata s3c2443_dma_platdata = {

For this patch:

Acked-by: Arnd Bergmann <arnd@arndb.de>