ASoC: samsung: pass DMA channels as pointers

commit b9a1a743 upstream.

ARM64 allmodconfig produces a bunch of warnings when building the
samsung ASoC code:

sound/soc/samsung/dmaengine.c: In function 'samsung_asoc_init_dma_data':
sound/soc/samsung/dmaengine.c:53:32: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
   playback_data->filter_data = (void *)playback->channel;
sound/soc/samsung/dmaengine.c:60:31: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
   capture_data->filter_data = (void *)capture->channel;

We could easily shut up the warning by adding an intermediate cast,
but there is a bigger underlying problem: The use of IORESOURCE_DMA
to pass data from platform code to device drivers is dubious to start
with, as what we really want is a pointer that can be passed into
a filter function.

Note that on s3c64xx, the pl08x DMA data is already a pointer, but
gets cast to resource_size_t so we can pass it as a resource, and it
then gets converted back to a pointer. In contrast, the data we pass
for s3c24xx is an index into a device specific table, and we artificially
convert that into a pointer for the filter function.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/arm/mach-s3c64xx/dev-audio.c

@@ -54,12 +54,12 @@ static int s3c64xx_i2s_cfg_gpio(struct platform_device *pdev)
 
 static struct resource s3c64xx_iis0_resource[] = {
 	[0] = DEFINE_RES_MEM(S3C64XX_PA_IIS0, SZ_256),
-	[1] = DEFINE_RES_DMA(DMACH_I2S0_OUT),
-	[2] = DEFINE_RES_DMA(DMACH_I2S0_IN),
 };
 
-static struct s3c_audio_pdata i2sv3_pdata = {
+static struct s3c_audio_pdata i2s0_pdata = {
 	.cfg_gpio = s3c64xx_i2s_cfg_gpio,
+	.dma_playback = DMACH_I2S0_OUT,
+	.dma_capture = DMACH_I2S0_IN,
 };
 
 struct platform_device s3c64xx_device_iis0 = {
@@ -68,15 +68,19 @@ struct platform_device s3c64xx_device_iis0 = {
 	.num_resources	  = ARRAY_SIZE(s3c64xx_iis0_resource),
 	.resource	  = s3c64xx_iis0_resource,
 	.dev = {
-		.platform_data = &i2sv3_pdata,
+		.platform_data = &i2s0_pdata,
 	},
 };
 EXPORT_SYMBOL(s3c64xx_device_iis0);
 
 static struct resource s3c64xx_iis1_resource[] = {
 	[0] = DEFINE_RES_MEM(S3C64XX_PA_IIS1, SZ_256),
-	[1] = DEFINE_RES_DMA(DMACH_I2S1_OUT),
-	[2] = DEFINE_RES_DMA(DMACH_I2S1_IN),
+};
+
+static struct s3c_audio_pdata i2s1_pdata = {
+	.cfg_gpio = s3c64xx_i2s_cfg_gpio,
+	.dma_playback = DMACH_I2S1_OUT,
+	.dma_capture = DMACH_I2S1_IN,
 };
 
 struct platform_device s3c64xx_device_iis1 = {
@@ -85,19 +89,19 @@ struct platform_device s3c64xx_device_iis1 = {
 	.num_resources	  = ARRAY_SIZE(s3c64xx_iis1_resource),
 	.resource	  = s3c64xx_iis1_resource,
 	.dev = {
-		.platform_data = &i2sv3_pdata,
+		.platform_data = &i2s1_pdata,
 	},
 };
 EXPORT_SYMBOL(s3c64xx_device_iis1);
 
 static struct resource s3c64xx_iisv4_resource[] = {
 	[0] = DEFINE_RES_MEM(S3C64XX_PA_IISV4, SZ_256),
-	[1] = DEFINE_RES_DMA(DMACH_HSI_I2SV40_TX),
-	[2] = DEFINE_RES_DMA(DMACH_HSI_I2SV40_RX),
 };
 
 static struct s3c_audio_pdata i2sv4_pdata = {
 	.cfg_gpio = s3c64xx_i2s_cfg_gpio,
+	.dma_playback = DMACH_HSI_I2SV40_TX,
+	.dma_capture = DMACH_HSI_I2SV40_RX,
 	.type = {
 		.i2s = {
 			.quirks = QUIRK_PRI_6CHAN,
@@ -142,12 +146,12 @@ static int s3c64xx_pcm_cfg_gpio(struct platform_device *pdev)
 
 static struct resource s3c64xx_pcm0_resource[] = {
 	[0] = DEFINE_RES_MEM(S3C64XX_PA_PCM0, SZ_256),
-	[1] = DEFINE_RES_DMA(DMACH_PCM0_TX),
-	[2] = DEFINE_RES_DMA(DMACH_PCM0_RX),
 };
 
 static struct s3c_audio_pdata s3c_pcm0_pdata = {
 	.cfg_gpio = s3c64xx_pcm_cfg_gpio,
+	.dma_capture = DMACH_PCM0_RX,
+	.dma_playback = DMACH_PCM0_TX,
 };
 
 struct platform_device s3c64xx_device_pcm0 = {
@@ -163,12 +167,12 @@ EXPORT_SYMBOL(s3c64xx_device_pcm0);
 
 static struct resource s3c64xx_pcm1_resource[] = {
 	[0] = DEFINE_RES_MEM(S3C64XX_PA_PCM1, SZ_256),
-	[1] = DEFINE_RES_DMA(DMACH_PCM1_TX),
-	[2] = DEFINE_RES_DMA(DMACH_PCM1_RX),
 };
 
 static struct s3c_audio_pdata s3c_pcm1_pdata = {
 	.cfg_gpio = s3c64xx_pcm_cfg_gpio,
+	.dma_playback = DMACH_PCM1_TX,
+	.dma_capture = DMACH_PCM1_RX,
 };
 
 struct platform_device s3c64xx_device_pcm1 = {
@@ -196,13 +200,14 @@ static int s3c64xx_ac97_cfg_gpe(struct platform_device *pdev)
 
 static struct resource s3c64xx_ac97_resource[] = {
 	[0] = DEFINE_RES_MEM(S3C64XX_PA_AC97, SZ_256),
-	[1] = DEFINE_RES_DMA(DMACH_AC97_PCMOUT),
-	[2] = DEFINE_RES_DMA(DMACH_AC97_PCMIN),
-	[3] = DEFINE_RES_DMA(DMACH_AC97_MICIN),
-	[4] = DEFINE_RES_IRQ(IRQ_AC97),
+	[1] = DEFINE_RES_IRQ(IRQ_AC97),
 };
 
-static struct s3c_audio_pdata s3c_ac97_pdata;
+static struct s3c_audio_pdata s3c_ac97_pdata = {
+	.dma_playback = DMACH_AC97_PCMOUT,
+	.dma_capture = DMACH_AC97_PCMIN,
+	.dma_capture_mic = DMACH_AC97_MICIN,
+};
 
 static u64 s3c64xx_ac97_dmamask = DMA_BIT_MASK(32);
 

arch/arm/mach-s3c64xx/include/mach/dma.h

@@ -14,38 +14,38 @@
 #define S3C64XX_DMA_CHAN(name)		((unsigned long)(name))
 
 /* DMA0/SDMA0 */
-#define DMACH_UART0		S3C64XX_DMA_CHAN("uart0_tx")
-#define DMACH_UART0_SRC2	S3C64XX_DMA_CHAN("uart0_rx")
-#define DMACH_UART1		S3C64XX_DMA_CHAN("uart1_tx")
-#define DMACH_UART1_SRC2	S3C64XX_DMA_CHAN("uart1_rx")
-#define DMACH_UART2		S3C64XX_DMA_CHAN("uart2_tx")
-#define DMACH_UART2_SRC2	S3C64XX_DMA_CHAN("uart2_rx")
-#define DMACH_UART3		S3C64XX_DMA_CHAN("uart3_tx")
-#define DMACH_UART3_SRC2	S3C64XX_DMA_CHAN("uart3_rx")
-#define DMACH_PCM0_TX		S3C64XX_DMA_CHAN("pcm0_tx")
-#define DMACH_PCM0_RX		S3C64XX_DMA_CHAN("pcm0_rx")
-#define DMACH_I2S0_OUT		S3C64XX_DMA_CHAN("i2s0_tx")
-#define DMACH_I2S0_IN		S3C64XX_DMA_CHAN("i2s0_rx")
+#define DMACH_UART0		"uart0_tx"
+#define DMACH_UART0_SRC2	"uart0_rx"
+#define DMACH_UART1		"uart1_tx"
+#define DMACH_UART1_SRC2	"uart1_rx"
+#define DMACH_UART2		"uart2_tx"
+#define DMACH_UART2_SRC2	"uart2_rx"
+#define DMACH_UART3		"uart3_tx"
+#define DMACH_UART3_SRC2	"uart3_rx"
+#define DMACH_PCM0_TX		"pcm0_tx"
+#define DMACH_PCM0_RX		"pcm0_rx"
+#define DMACH_I2S0_OUT		"i2s0_tx"
+#define DMACH_I2S0_IN		"i2s0_rx"
 #define DMACH_SPI0_TX		S3C64XX_DMA_CHAN("spi0_tx")
 #define DMACH_SPI0_RX		S3C64XX_DMA_CHAN("spi0_rx")
-#define DMACH_HSI_I2SV40_TX	S3C64XX_DMA_CHAN("i2s2_tx")
-#define DMACH_HSI_I2SV40_RX	S3C64XX_DMA_CHAN("i2s2_rx")
+#define DMACH_HSI_I2SV40_TX	"i2s2_tx"
+#define DMACH_HSI_I2SV40_RX	"i2s2_rx"
 
 /* DMA1/SDMA1 */
-#define DMACH_PCM1_TX		S3C64XX_DMA_CHAN("pcm1_tx")
-#define DMACH_PCM1_RX		S3C64XX_DMA_CHAN("pcm1_rx")
-#define DMACH_I2S1_OUT		S3C64XX_DMA_CHAN("i2s1_tx")
-#define DMACH_I2S1_IN		S3C64XX_DMA_CHAN("i2s1_rx")
+#define DMACH_PCM1_TX		"pcm1_tx"
+#define DMACH_PCM1_RX		"pcm1_rx"
+#define DMACH_I2S1_OUT		"i2s1_tx"
+#define DMACH_I2S1_IN		"i2s1_rx"
 #define DMACH_SPI1_TX		S3C64XX_DMA_CHAN("spi1_tx")
 #define DMACH_SPI1_RX		S3C64XX_DMA_CHAN("spi1_rx")
-#define DMACH_AC97_PCMOUT	S3C64XX_DMA_CHAN("ac97_out")
-#define DMACH_AC97_PCMIN	S3C64XX_DMA_CHAN("ac97_in")
-#define DMACH_AC97_MICIN	S3C64XX_DMA_CHAN("ac97_mic")
-#define DMACH_PWM		S3C64XX_DMA_CHAN("pwm")
-#define DMACH_IRDA		S3C64XX_DMA_CHAN("irda")
-#define DMACH_EXTERNAL		S3C64XX_DMA_CHAN("external")
-#define DMACH_SECURITY_RX	S3C64XX_DMA_CHAN("sec_rx")
-#define DMACH_SECURITY_TX	S3C64XX_DMA_CHAN("sec_tx")
+#define DMACH_AC97_PCMOUT	"ac97_out"
+#define DMACH_AC97_PCMIN	"ac97_in"
+#define DMACH_AC97_MICIN	"ac97_mic"
+#define DMACH_PWM		"pwm"
+#define DMACH_IRDA		"irda"
+#define DMACH_EXTERNAL		"external"
+#define DMACH_SECURITY_RX	"sec_rx"
+#define DMACH_SECURITY_TX	"sec_tx"
 
 enum dma_ch {
 	DMACH_MAX = 32

arch/arm/plat-samsung/devs.c

@@ -65,6 +65,7 @@
 #include <linux/platform_data/usb-ohci-s3c2410.h>
 #include <plat/usb-phy.h>
 #include <plat/regs-spi.h>
+#include <linux/platform_data/asoc-s3c.h>
 #include <linux/platform_data/spi-s3c64xx.h>
 
 static u64 samsung_device_dma_mask = DMA_BIT_MASK(32);
@@ -74,9 +75,12 @@ static u64 samsung_device_dma_mask = DMA_BIT_MASK(32);
 static struct resource s3c_ac97_resource[] = {
 	[0] = DEFINE_RES_MEM(S3C2440_PA_AC97, S3C2440_SZ_AC97),
 	[1] = DEFINE_RES_IRQ(IRQ_S3C244X_AC97),
-	[2] = DEFINE_RES_DMA_NAMED(DMACH_PCM_OUT, "PCM out"),
-	[3] = DEFINE_RES_DMA_NAMED(DMACH_PCM_IN, "PCM in"),
-	[4] = DEFINE_RES_DMA_NAMED(DMACH_MIC_IN, "Mic in"),
+};
+
+static struct s3c_audio_pdata s3c_ac97_pdata = {
+	.dma_playback = (void *)DMACH_PCM_OUT,
+	.dma_capture = (void *)DMACH_PCM_IN,
+	.dma_capture_mic = (void *)DMACH_MIC_IN,
 };
 
 struct platform_device s3c_device_ac97 = {
@@ -87,6 +91,7 @@ struct platform_device s3c_device_ac97 = {
 	.dev		= {
 		.dma_mask		= &samsung_device_dma_mask,
 		.coherent_dma_mask	= DMA_BIT_MASK(32),
+		.platform_data		= &s3c_ac97_pdata,
 	}
 };
 #endif /* CONFIG_CPU_S3C2440 */

include/linux/platform_data/asoc-s3c.h

@@ -39,6 +39,10 @@ struct samsung_i2s {
  */
 struct s3c_audio_pdata {
 	int (*cfg_gpio)(struct platform_device *);
+	void *dma_playback;
+	void *dma_capture;
+	void *dma_play_sec;
+	void *dma_capture_mic;
 	union {
 		struct samsung_i2s i2s;
 	} type;

sound/soc/samsung/ac97.c

@@ -324,7 +324,7 @@ static const struct snd_soc_component_driver s3c_ac97_component = {
 
 static int s3c_ac97_probe(struct platform_device *pdev)
 {
-	struct resource *mem_res, *dmatx_res, *dmarx_res, *dmamic_res, *irq_res;
+	struct resource *mem_res, *irq_res;
 	struct s3c_audio_pdata *ac97_pdata;
 	int ret;
 
@@ -335,24 +335,6 @@ static int s3c_ac97_probe(struct platform_device *pdev)
 	}
 
 	/* Check for availability of necessary resource */
-	dmatx_res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
-	if (!dmatx_res) {
-		dev_err(&pdev->dev, "Unable to get AC97-TX dma resource\n");
-		return -ENXIO;
-	}
-
-	dmarx_res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
-	if (!dmarx_res) {
-		dev_err(&pdev->dev, "Unable to get AC97-RX dma resource\n");
-		return -ENXIO;
-	}
-
-	dmamic_res = platform_get_resource(pdev, IORESOURCE_DMA, 2);
-	if (!dmamic_res) {
-		dev_err(&pdev->dev, "Unable to get AC97-MIC dma resource\n");
-		return -ENXIO;
-	}
-
 	irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (!irq_res) {
 		dev_err(&pdev->dev, "AC97 IRQ not provided!\n");
@@ -364,11 +346,11 @@ static int s3c_ac97_probe(struct platform_device *pdev)
 	if (IS_ERR(s3c_ac97.regs))
 		return PTR_ERR(s3c_ac97.regs);
 
-	s3c_ac97_pcm_out.channel = dmatx_res->start;
+	s3c_ac97_pcm_out.slave = ac97_pdata->dma_playback;
 	s3c_ac97_pcm_out.dma_addr = mem_res->start + S3C_AC97_PCM_DATA;
-	s3c_ac97_pcm_in.channel = dmarx_res->start;
+	s3c_ac97_pcm_in.slave = ac97_pdata->dma_capture;
 	s3c_ac97_pcm_in.dma_addr = mem_res->start + S3C_AC97_PCM_DATA;
-	s3c_ac97_mic_in.channel = dmamic_res->start;
+	s3c_ac97_mic_in.slave = ac97_pdata->dma_capture_mic;
 	s3c_ac97_mic_in.dma_addr = mem_res->start + S3C_AC97_MIC_DATA;
 
 	init_completion(&s3c_ac97.done);

sound/soc/samsung/dma.h

@@ -15,7 +15,7 @@
 #include <sound/dmaengine_pcm.h>
 
 struct s3c_dma_params {
-	int channel;				/* Channel ID */
+	void *slave;				/* Channel ID */
 	dma_addr_t dma_addr;
 	int dma_size;			/* Size of the DMA transfer */
 	char *ch_name;

sound/soc/samsung/dmaengine.c

@@ -50,14 +50,14 @@ void samsung_asoc_init_dma_data(struct snd_soc_dai *dai,
 
 	if (playback) {
 		playback_data = &playback->dma_data;
-		playback_data->filter_data = (void *)playback->channel;
+		playback_data->filter_data = playback->slave;
 		playback_data->chan_name = playback->ch_name;
 		playback_data->addr = playback->dma_addr;
 		playback_data->addr_width = playback->dma_size;
 	}
 	if (capture) {
 		capture_data = &capture->dma_data;
-		capture_data->filter_data = (void *)capture->channel;
+		capture_data->filter_data = capture->slave;
 		capture_data->chan_name = capture->ch_name;
 		capture_data->addr = capture->dma_addr;
 		capture_data->addr_width = capture->dma_size;

sound/soc/samsung/i2s.c

@@ -1260,27 +1260,14 @@ static int samsung_i2s_probe(struct platform_device *pdev)
 	pri_dai->lock = &pri_dai->spinlock;
 
 	if (!np) {
-		res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
-		if (!res) {
-			dev_err(&pdev->dev,
-				"Unable to get I2S-TX dma resource\n");
-			return -ENXIO;
-		}
-		pri_dai->dma_playback.channel = res->start;
-
-		res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
-		if (!res) {
-			dev_err(&pdev->dev,
-				"Unable to get I2S-RX dma resource\n");
-			return -ENXIO;
-		}
-		pri_dai->dma_capture.channel = res->start;
-
 		if (i2s_pdata == NULL) {
 			dev_err(&pdev->dev, "Can't work without s3c_audio_pdata\n");
 			return -EINVAL;
 		}
 
+		pri_dai->dma_playback.slave = i2s_pdata->dma_playback;
+		pri_dai->dma_capture.slave = i2s_pdata->dma_capture;
+
 		if (&i2s_pdata->type)
 			i2s_cfg = &i2s_pdata->type.i2s;
 
@@ -1341,11 +1328,8 @@ static int samsung_i2s_probe(struct platform_device *pdev)
 		sec_dai->dma_playback.dma_addr = regs_base + I2STXDS;
 		sec_dai->dma_playback.ch_name = "tx-sec";
 
-		if (!np) {
-			res = platform_get_resource(pdev, IORESOURCE_DMA, 2);
-			if (res)
-				sec_dai->dma_playback.channel = res->start;
-		}
+		if (!np)
+			sec_dai->dma_playback.slave = i2s_pdata->dma_play_sec;
 
 		sec_dai->dma_playback.dma_size = 4;
 		sec_dai->addr = pri_dai->addr;

sound/soc/samsung/pcm.c

@@ -486,7 +486,7 @@ static const struct snd_soc_component_driver s3c_pcm_component = {
 static int s3c_pcm_dev_probe(struct platform_device *pdev)
 {
 	struct s3c_pcm_info *pcm;
-	struct resource *mem_res, *dmatx_res, *dmarx_res;
+	struct resource *mem_res;
 	struct s3c_audio_pdata *pcm_pdata;
 	int ret;
 
@@ -499,18 +499,6 @@ static int s3c_pcm_dev_probe(struct platform_device *pdev)
 	pcm_pdata = pdev->dev.platform_data;
 
 	/* Check for availability of necessary resource */
-	dmatx_res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
-	if (!dmatx_res) {
-		dev_err(&pdev->dev, "Unable to get PCM-TX dma resource\n");
-		return -ENXIO;
-	}
-
-	dmarx_res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
-	if (!dmarx_res) {
-		dev_err(&pdev->dev, "Unable to get PCM-RX dma resource\n");
-		return -ENXIO;
-	}
-
 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!mem_res) {
 		dev_err(&pdev->dev, "Unable to get register resource\n");
@@ -568,8 +556,10 @@ static int s3c_pcm_dev_probe(struct platform_device *pdev)
 	s3c_pcm_stereo_out[pdev->id].dma_addr = mem_res->start
 							+ S3C_PCM_TXFIFO;
 
-	s3c_pcm_stereo_in[pdev->id].channel = dmarx_res->start;
-	s3c_pcm_stereo_out[pdev->id].channel = dmatx_res->start;
+	if (pcm_pdata) {
+		s3c_pcm_stereo_in[pdev->id].slave = pcm_pdata->dma_capture;
+		s3c_pcm_stereo_out[pdev->id].slave = pcm_pdata->dma_playback;
+	}
 
 	pcm->dma_capture = &s3c_pcm_stereo_in[pdev->id];
 	pcm->dma_playback = &s3c_pcm_stereo_out[pdev->id];

sound/soc/samsung/s3c2412-i2s.c

@@ -34,13 +34,13 @@
 #include "s3c2412-i2s.h"
 
 static struct s3c_dma_params s3c2412_i2s_pcm_stereo_out = {
-	.channel	= DMACH_I2S_OUT,
+	.slave		= (void *)(uintptr_t)DMACH_I2S_OUT,
 	.ch_name	= "tx",
 	.dma_size	= 4,
 };
 
 static struct s3c_dma_params s3c2412_i2s_pcm_stereo_in = {
-	.channel	= DMACH_I2S_IN,
+	.slave		= (void *)(uintptr_t)DMACH_I2S_IN,
 	.ch_name	= "rx",
 	.dma_size	= 4,
 };

sound/soc/samsung/s3c24xx-i2s.c

@@ -32,13 +32,13 @@
 #include "s3c24xx-i2s.h"
 
 static struct s3c_dma_params s3c24xx_i2s_pcm_stereo_out = {
-	.channel	= DMACH_I2S_OUT,
+	.slave		= (void *)(uintptr_t)DMACH_I2S_OUT,
 	.ch_name	= "tx",
 	.dma_size	= 2,
 };
 
 static struct s3c_dma_params s3c24xx_i2s_pcm_stereo_in = {
-	.channel	= DMACH_I2S_IN,
+	.slave		= (void *)(uintptr_t)DMACH_I2S_IN,
 	.ch_name	= "rx",
 	.dma_size	= 2,
 };

sound/soc/samsung/spdif.c

@@ -359,7 +359,7 @@ static const struct snd_soc_component_driver samsung_spdif_component = {
 static int spdif_probe(struct platform_device *pdev)
 {
 	struct s3c_audio_pdata *spdif_pdata;
-	struct resource *mem_res, *dma_res;
+	struct resource *mem_res;
 	struct samsung_spdif_info *spdif;
 	int ret;
 
@@ -367,12 +367,6 @@ static int spdif_probe(struct platform_device *pdev)
 
 	dev_dbg(&pdev->dev, "Entered %s\n", __func__);
 
-	dma_res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
-	if (!dma_res) {
-		dev_err(&pdev->dev, "Unable to get dma resource.\n");
-		return -ENXIO;
-	}
-
 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!mem_res) {
 		dev_err(&pdev->dev, "Unable to get register resource.\n");
@@ -432,7 +426,7 @@ static int spdif_probe(struct platform_device *pdev)
 
 	spdif_stereo_out.dma_size = 2;
 	spdif_stereo_out.dma_addr = mem_res->start + DATA_OUTBUF;
-	spdif_stereo_out.channel = dma_res->start;
+	spdif_stereo_out.slave = spdif_pdata ? spdif_pdata->dma_playback : NULL;
 
 	spdif->dma_playback = &spdif_stereo_out;