[alsa-devel] [PATCH] ALSA: fix DMA channel selection in Freescale MPC8610 sound drivers

[Takashi Iwai]

At Wed,  6 Aug 2008 15:01:01 -0500,
Timur Tabi wrote:
> 
> On the Freescale MPC8610, SSI1 is hard-coded to use DMA channels 0 and 1
> for playback and capture, and SSI2 is hard-coded to use DMA channels 2 and 3.
> This patch fixes the fabric driver so that it uses the right channels.
> 
> Signed-off-by: Timur Tabi <timur at freescale.com>

Thanks, applied.


Takashi

> ---
>  sound/soc/fsl/mpc8610_hpcd.c |   26 +++++++++++++++-----------
>  1 files changed, 15 insertions(+), 11 deletions(-)
> 
> diff --git a/sound/soc/fsl/mpc8610_hpcd.c b/sound/soc/fsl/mpc8610_hpcd.c
> index 4bdc9d8..94f89de 100644
> --- a/sound/soc/fsl/mpc8610_hpcd.c
> +++ b/sound/soc/fsl/mpc8610_hpcd.c
> @@ -68,10 +68,6 @@ static int mpc8610_hpcd_machine_probe(struct platform_device *sound_device)
>  	guts_set_pmuxcr_dma(machine_data->guts, machine_data->dma_id,
>  		machine_data->dma_channel_id[1], 0);
>  
> -	guts_set_pmuxcr_dma(machine_data->guts, 1, 0, 0);
> -	guts_set_pmuxcr_dma(machine_data->guts, 1, 3, 0);
> -	guts_set_pmuxcr_dma(machine_data->guts, 0, 3, 0);
> -
>  	switch (machine_data->ssi_id) {
>  	case 0:
>  		clrsetbits_be32(&machine_data->guts->pmuxcr,
> @@ -230,6 +226,8 @@ static int mpc8610_hpcd_probe(struct of_device *ofdev,
>  	struct fsl_ssi_info ssi_info;
>  	struct fsl_dma_info dma_info;
>  	int ret = -ENODEV;
> +	unsigned int playback_dma_channel;
> +	unsigned int capture_dma_channel;
>  
>  	machine_data = kzalloc(sizeof(struct mpc8610_hpcd_data), GFP_KERNEL);
>  	if (!machine_data)
> @@ -381,8 +379,9 @@ static int mpc8610_hpcd_probe(struct of_device *ofdev,
>  		goto error;
>  	}
>  
> -	/* Find the DMA channels to use.  For now, we always use the first DMA
> -	   controller. */
> +	/* Find the DMA channels to use.  Both SSIs need to use the same DMA
> +	 * controller, so let's use DMA#1.
> +	 */
>  	for_each_compatible_node(dma_np, NULL, "fsl,mpc8610-dma") {
>  		iprop = of_get_property(dma_np, "cell-index", NULL);
>  		if (iprop && (*iprop == 0)) {
> @@ -397,14 +396,19 @@ static int mpc8610_hpcd_probe(struct of_device *ofdev,
>  	}
>  	machine_data->dma_id = *iprop;
>  
> +	/* SSI1 needs to use DMA Channels 0 and 1, and SSI2 needs to use DMA
> +	 * channels 2 and 3.  This is just how the MPC8610 is wired
> +	 * internally.
> +	 */
> +	playback_dma_channel = (machine_data->ssi_id == 0) ? 0 : 2;
> +	capture_dma_channel = (machine_data->ssi_id == 0) ? 1 : 3;
> +
>  	/*
> -	 * Find the DMA channels to use.  For now, we always use DMA channel 0
> -	 * for playback, and DMA channel 1 for capture.
> +	 * Find the DMA channels to use.
>  	 */
>  	while ((dma_channel_np = of_get_next_child(dma_np, dma_channel_np))) {
>  		iprop = of_get_property(dma_channel_np, "cell-index", NULL);
> -		/* Is it DMA channel 0? */
> -		if (iprop && (*iprop == 0)) {
> +		if (iprop && (*iprop == playback_dma_channel)) {
>  			/* dma_channel[0] and dma_irq[0] are for playback */
>  			dma_info.dma_channel[0] = of_iomap(dma_channel_np, 0);
>  			dma_info.dma_irq[0] =
> @@ -412,7 +416,7 @@ static int mpc8610_hpcd_probe(struct of_device *ofdev,
>  			machine_data->dma_channel_id[0] = *iprop;
>  			continue;
>  		}
> -		if (iprop && (*iprop == 1)) {
> +		if (iprop && (*iprop == capture_dma_channel)) {
>  			/* dma_channel[1] and dma_irq[1] are for capture */
>  			dma_info.dma_channel[1] = of_iomap(dma_channel_np, 0);
>  			dma_info.dma_irq[1] =
> -- 
> 1.5.5
>