[v2] ASoC: davinci-mcasp: Choose PCM driver based on configured DMA controller
diff mbox

Message ID 7230089f10ea27a9bd76eb8bfffcef754e71f274.1433252849.git.jsarha@ti.com
State New
Headers show

Commit Message

Jyri Sarha June 2, 2015, 1:49 p.m. UTC
Find the configured DMA controller by asking for a DMA channel in the
probe phase and releasing it right after. The controller device can be
found via the dma_chan struct and the controller is recognized from
the compatible property of its device node. The patch assumes EDMA if
there is no device node.

Signed-off-by: Jyri Sarha <jsarha@ti.com>
---
Changes since first patch version:
- Change enum names from MCASP_?DMA to PCM_?DMA
- Return PCM_EDMA if !mcasp->dev->of_node
- Do not ignore possible error code returned by
  davinci_mcasp_get_dma_type()

 sound/soc/davinci/davinci-mcasp.c | 68 +++++++++++++++++++++++++++++++++------
 1 file changed, 58 insertions(+), 10 deletions(-)

Comments

Lopez Cruz, Misael June 2, 2015, 4:16 p.m. UTC | #1
Jyri,

On 06/02/2015 08:49 AM, Jyri Sarha wrote:
> Find the configured DMA controller by asking for a DMA channel in the
> probe phase and releasing it right after. The controller device can be
> found via the dma_chan struct and the controller is recognized from
> the compatible property of its device node. The patch assumes EDMA if
> there is no device node.
>
> Signed-off-by: Jyri Sarha <jsarha@ti.com>
> ---
> Changes since first patch version:
> - Change enum names from MCASP_?DMA to PCM_?DMA
> - Return PCM_EDMA if !mcasp->dev->of_node
> - Do not ignore possible error code returned by
>    davinci_mcasp_get_dma_type()
>
>   sound/soc/davinci/davinci-mcasp.c | 68 +++++++++++++++++++++++++++++++++------
>   1 file changed, 58 insertions(+), 10 deletions(-)
>
> diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c
> index d793494..3b78c3e 100644
> --- a/sound/soc/davinci/davinci-mcasp.c
> +++ b/sound/soc/davinci/davinci-mcasp.c
> @@ -1565,6 +1565,49 @@ static int davinci_mcasp_init_ch_constraints(struct davinci_mcasp *mcasp)
>   	return ret;
>   }
>
> +enum {
> +	PCM_EDMA,
> +	PCM_SDMA,
> +};
> +static const char *sdma_prefix = "ti,omap";
> +
> +static int davinci_mcasp_get_dma_type(struct davinci_mcasp *mcasp)
> +{
> +	struct dma_chan *chan;
> +	const char *tmp;
> +	int ret = PCM_EDMA;
> +
> +	if (!mcasp->dev->of_node)
> +		return PCM_EDMA;
> +
> +	tmp = mcasp->dma_data[SNDRV_PCM_STREAM_PLAYBACK].filter_data;
> +	chan = dma_request_slave_channel_reason(mcasp->dev, tmp);
> +	if (IS_ERR(chan)) {
> +		if (PTR_ERR(chan) != -EPROBE_DEFER)
> +			dev_err(mcasp->dev,
> +				"Can't verify DMA configuration (%ld)\n",
> +				PTR_ERR(chan));
> +		return PTR_ERR(chan);
> +	}
> +	BUG_ON(!chan->device || !chan->device->dev);
> +
> +	if (chan->device->dev->of_node)
> +		ret = of_property_read_string(chan->device->dev->of_node,
> +					      "compatible", &tmp);

I wonder how this is going to play out when the DMA crossbar is present 
(i.e. dra7 family).

In that case, isn't the 'compatible' string here that of the DMA 
crossbar (not the one from the DMA controller)?

> +	else
> +		dev_dbg(mcasp->dev, "DMA controller has no of-node\n");
> +
> +	dma_release_channel(chan);
> +	if (ret)
> +		return ret;
> +
> +	dev_dbg(mcasp->dev, "DMA controller compatible = \"%s\"\n", tmp);
> +	if (!strncmp(tmp, sdma_prefix, strlen(sdma_prefix)))
> +		return PCM_SDMA;
> +
> +	return PCM_EDMA;
> +}
> +
>   static int davinci_mcasp_probe(struct platform_device *pdev)
>   {
>   	struct snd_dmaengine_dai_dma_data *dma_data;
> @@ -1763,27 +1806,32 @@ static int davinci_mcasp_probe(struct platform_device *pdev)
>   	if (ret != 0)
>   		goto err;
>
> -	switch (mcasp->version) {
> +	ret = davinci_mcasp_get_dma_type(mcasp);
> +	switch (ret) {
> +	case PCM_EDMA:
>   #if IS_BUILTIN(CONFIG_SND_EDMA_SOC) || \
>   	(IS_MODULE(CONFIG_SND_DAVINCI_SOC_MCASP) && \
>   	 IS_MODULE(CONFIG_SND_EDMA_SOC))
> -	case MCASP_VERSION_1:
> -	case MCASP_VERSION_2:
> -	case MCASP_VERSION_3:
>   		ret = edma_pcm_platform_register(&pdev->dev);
> -		break;
> +#else
> +		dev_err(&pdev->dev, "Missing SND_EDMA_SOC\n");
> +		ret = -EINVAL;
>   #endif
> +		break;
> +	case PCM_SDMA:
>   #if IS_BUILTIN(CONFIG_SND_OMAP_SOC) || \
>   	(IS_MODULE(CONFIG_SND_DAVINCI_SOC_MCASP) && \
>   	 IS_MODULE(CONFIG_SND_OMAP_SOC))
> -	case MCASP_VERSION_4:
>   		ret = omap_pcm_platform_register(&pdev->dev);
> -		break;
> +#else
> +		dev_err(&pdev->dev, "Missing SND_SDMA_SOC\n");
> +		ret = -EINVAL;
>   #endif
> +		break;
> +	case -EPROBE_DEFER:
> +		break;
>   	default:
> -		dev_err(&pdev->dev, "Invalid McASP version: %d\n",
> -			mcasp->version);
> -		ret = -EINVAL;
> +		dev_err(&pdev->dev, "No DMA controller found (%d)\n", ret);
>   		break;
>   	}
>
>
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Jyri Sarha June 2, 2015, 8:04 p.m. UTC | #2
On 06/02/15 19:16, Misael Lopez Cruz wrote:
> Jyri,
>
> On 06/02/2015 08:49 AM, Jyri Sarha wrote:
>> Find the configured DMA controller by asking for a DMA channel in the
>> probe phase and releasing it right after. The controller device can be
>> found via the dma_chan struct and the controller is recognized from
>> the compatible property of its device node. The patch assumes EDMA if
>> there is no device node.
>>
>> Signed-off-by: Jyri Sarha <jsarha@ti.com>
>> ---
>> Changes since first patch version:
>> - Change enum names from MCASP_?DMA to PCM_?DMA
>> - Return PCM_EDMA if !mcasp->dev->of_node
>> - Do not ignore possible error code returned by
>>    davinci_mcasp_get_dma_type()
>>
>>   sound/soc/davinci/davinci-mcasp.c | 68
>> +++++++++++++++++++++++++++++++++------
>>   1 file changed, 58 insertions(+), 10 deletions(-)
>>
>> diff --git a/sound/soc/davinci/davinci-mcasp.c
>> b/sound/soc/davinci/davinci-mcasp.c
>> index d793494..3b78c3e 100644
>> --- a/sound/soc/davinci/davinci-mcasp.c
>> +++ b/sound/soc/davinci/davinci-mcasp.c
>> @@ -1565,6 +1565,49 @@ static int
>> davinci_mcasp_init_ch_constraints(struct davinci_mcasp *mcasp)
>>       return ret;
>>   }
>>
>> +enum {
>> +    PCM_EDMA,
>> +    PCM_SDMA,
>> +};
>> +static const char *sdma_prefix = "ti,omap";
>> +
>> +static int davinci_mcasp_get_dma_type(struct davinci_mcasp *mcasp)
>> +{
>> +    struct dma_chan *chan;
>> +    const char *tmp;
>> +    int ret = PCM_EDMA;
>> +
>> +    if (!mcasp->dev->of_node)
>> +        return PCM_EDMA;
>> +
>> +    tmp = mcasp->dma_data[SNDRV_PCM_STREAM_PLAYBACK].filter_data;
>> +    chan = dma_request_slave_channel_reason(mcasp->dev, tmp);
>> +    if (IS_ERR(chan)) {
>> +        if (PTR_ERR(chan) != -EPROBE_DEFER)
>> +            dev_err(mcasp->dev,
>> +                "Can't verify DMA configuration (%ld)\n",
>> +                PTR_ERR(chan));
>> +        return PTR_ERR(chan);
>> +    }
>> +    BUG_ON(!chan->device || !chan->device->dev);
>> +
>> +    if (chan->device->dev->of_node)
>> +        ret = of_property_read_string(chan->device->dev->of_node,
>> +                          "compatible", &tmp);
>
> I wonder how this is going to play out when the DMA crossbar is present
> (i.e. dra7 family).
>
> In that case, isn't the 'compatible' string here that of the DMA
> crossbar (not the one from the DMA controller)?

That is exactly why I am requesting a channel and going from there. The 
DMA router will do its thing in the middle and the device pointer found 
via the returned dma_chan is pointing at the actual DMA controller.

I have tested the code on am57xx-beagle-x15, which is also using the DMA 
crossbar.

>
>> +    else
>> +        dev_dbg(mcasp->dev, "DMA controller has no of-node\n");
>> +
>> +    dma_release_channel(chan);
>> +    if (ret)
>> +        return ret;
>> +
>> +    dev_dbg(mcasp->dev, "DMA controller compatible = \"%s\"\n", tmp);
>> +    if (!strncmp(tmp, sdma_prefix, strlen(sdma_prefix)))
>> +        return PCM_SDMA;
>> +
>> +    return PCM_EDMA;
>> +}
>> +
>>   static int davinci_mcasp_probe(struct platform_device *pdev)
>>   {
>>       struct snd_dmaengine_dai_dma_data *dma_data;
>> @@ -1763,27 +1806,32 @@ static int davinci_mcasp_probe(struct
>> platform_device *pdev)
>>       if (ret != 0)
>>           goto err;
>>
>> -    switch (mcasp->version) {
>> +    ret = davinci_mcasp_get_dma_type(mcasp);
>> +    switch (ret) {
>> +    case PCM_EDMA:
>>   #if IS_BUILTIN(CONFIG_SND_EDMA_SOC) || \
>>       (IS_MODULE(CONFIG_SND_DAVINCI_SOC_MCASP) && \
>>        IS_MODULE(CONFIG_SND_EDMA_SOC))
>> -    case MCASP_VERSION_1:
>> -    case MCASP_VERSION_2:
>> -    case MCASP_VERSION_3:
>>           ret = edma_pcm_platform_register(&pdev->dev);
>> -        break;
>> +#else
>> +        dev_err(&pdev->dev, "Missing SND_EDMA_SOC\n");
>> +        ret = -EINVAL;
>>   #endif
>> +        break;
>> +    case PCM_SDMA:
>>   #if IS_BUILTIN(CONFIG_SND_OMAP_SOC) || \
>>       (IS_MODULE(CONFIG_SND_DAVINCI_SOC_MCASP) && \
>>        IS_MODULE(CONFIG_SND_OMAP_SOC))
>> -    case MCASP_VERSION_4:
>>           ret = omap_pcm_platform_register(&pdev->dev);
>> -        break;
>> +#else
>> +        dev_err(&pdev->dev, "Missing SND_SDMA_SOC\n");
>> +        ret = -EINVAL;
>>   #endif
>> +        break;
>> +    case -EPROBE_DEFER:
>> +        break;
>>       default:
>> -        dev_err(&pdev->dev, "Invalid McASP version: %d\n",
>> -            mcasp->version);
>> -        ret = -EINVAL;
>> +        dev_err(&pdev->dev, "No DMA controller found (%d)\n", ret);
>>           break;
>>       }
>>
>>

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Patch
diff mbox

diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c
index d793494..3b78c3e 100644
--- a/sound/soc/davinci/davinci-mcasp.c
+++ b/sound/soc/davinci/davinci-mcasp.c
@@ -1565,6 +1565,49 @@  static int davinci_mcasp_init_ch_constraints(struct davinci_mcasp *mcasp)
 	return ret;
 }
 
+enum {
+	PCM_EDMA,
+	PCM_SDMA,
+};
+static const char *sdma_prefix = "ti,omap";
+
+static int davinci_mcasp_get_dma_type(struct davinci_mcasp *mcasp)
+{
+	struct dma_chan *chan;
+	const char *tmp;
+	int ret = PCM_EDMA;
+
+	if (!mcasp->dev->of_node)
+		return PCM_EDMA;
+
+	tmp = mcasp->dma_data[SNDRV_PCM_STREAM_PLAYBACK].filter_data;
+	chan = dma_request_slave_channel_reason(mcasp->dev, tmp);
+	if (IS_ERR(chan)) {
+		if (PTR_ERR(chan) != -EPROBE_DEFER)
+			dev_err(mcasp->dev,
+				"Can't verify DMA configuration (%ld)\n",
+				PTR_ERR(chan));
+		return PTR_ERR(chan);
+	}
+	BUG_ON(!chan->device || !chan->device->dev);
+
+	if (chan->device->dev->of_node)
+		ret = of_property_read_string(chan->device->dev->of_node,
+					      "compatible", &tmp);
+	else
+		dev_dbg(mcasp->dev, "DMA controller has no of-node\n");
+
+	dma_release_channel(chan);
+	if (ret)
+		return ret;
+
+	dev_dbg(mcasp->dev, "DMA controller compatible = \"%s\"\n", tmp);
+	if (!strncmp(tmp, sdma_prefix, strlen(sdma_prefix)))
+		return PCM_SDMA;
+
+	return PCM_EDMA;
+}
+
 static int davinci_mcasp_probe(struct platform_device *pdev)
 {
 	struct snd_dmaengine_dai_dma_data *dma_data;
@@ -1763,27 +1806,32 @@  static int davinci_mcasp_probe(struct platform_device *pdev)
 	if (ret != 0)
 		goto err;
 
-	switch (mcasp->version) {
+	ret = davinci_mcasp_get_dma_type(mcasp);
+	switch (ret) {
+	case PCM_EDMA:
 #if IS_BUILTIN(CONFIG_SND_EDMA_SOC) || \
 	(IS_MODULE(CONFIG_SND_DAVINCI_SOC_MCASP) && \
 	 IS_MODULE(CONFIG_SND_EDMA_SOC))
-	case MCASP_VERSION_1:
-	case MCASP_VERSION_2:
-	case MCASP_VERSION_3:
 		ret = edma_pcm_platform_register(&pdev->dev);
-		break;
+#else
+		dev_err(&pdev->dev, "Missing SND_EDMA_SOC\n");
+		ret = -EINVAL;
 #endif
+		break;
+	case PCM_SDMA:
 #if IS_BUILTIN(CONFIG_SND_OMAP_SOC) || \
 	(IS_MODULE(CONFIG_SND_DAVINCI_SOC_MCASP) && \
 	 IS_MODULE(CONFIG_SND_OMAP_SOC))
-	case MCASP_VERSION_4:
 		ret = omap_pcm_platform_register(&pdev->dev);
-		break;
+#else
+		dev_err(&pdev->dev, "Missing SND_SDMA_SOC\n");
+		ret = -EINVAL;
 #endif
+		break;
+	case -EPROBE_DEFER:
+		break;
 	default:
-		dev_err(&pdev->dev, "Invalid McASP version: %d\n",
-			mcasp->version);
-		ret = -EINVAL;
+		dev_err(&pdev->dev, "No DMA controller found (%d)\n", ret);
 		break;
 	}