Re: [PATCH 05/10] ASoC: fsl_sai: Add support to enable multiple data lines

[Lucas Stach <l.stach@pengutronix.de>]

Am Montag, den 22.07.2019, 15:48 +0300 schrieb Daniel Baluta:
> SAI supports up to 8 Rx/Tx data lines which can be enabled
> using TCE/RCE bits of TCR3/RCR3 registers.
> 
> Data lines to be enabled are read from DT fsl,dl_mask property.
> By default (if no DT entry is provided) only data line 0 is enabled.
> 
> Note:
> We can only enable consecutive data lines starting with data line #0.

Why is the property a bitmask then? To me this sounds like we want to
have the number of lanes in the DT and convert to the bitmask inside
the driver.

> > Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
> ---
>  sound/soc/fsl/fsl_sai.c | 10 +++++++++-
>  sound/soc/fsl/fsl_sai.h |  6 ++++--
>  2 files changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c
> index 768341608695..d0fa02188b7c 100644
> --- a/sound/soc/fsl/fsl_sai.c
> +++ b/sound/soc/fsl/fsl_sai.c
> @@ -601,7 +601,7 @@ static int fsl_sai_startup(struct snd_pcm_substream *substream,
>  
> >  	regmap_update_bits(sai->regmap, FSL_SAI_xCR3(tx),
> >  			   FSL_SAI_CR3_TRCE_MASK,
> > -			   FSL_SAI_CR3_TRCE);
> > +			   FSL_SAI_CR3_TRCE(sai->soc_data->dl_mask[tx]);
>  
> >  	ret = snd_pcm_hw_constraint_list(substream->runtime, 0,
> >  			SNDRV_PCM_HW_PARAM_RATE, &fsl_sai_rate_constraints);
> @@ -887,6 +887,14 @@ static int fsl_sai_probe(struct platform_device *pdev)
> >  		}
> >  	}
>  
> > +	/* active data lines mask for TX/RX, defaults to 1 (only the first
> > +	 * data line is enabled
> +	 */

Comment style not in line with Linux coding style.

Regards,
Lucas

> +	sai->dl_mask[RX] = 1;
> > +	sai->dl_mask[TX] = 1;
> > +	of_property_read_u32_index(np, "fsl,dl_mask", RX, &sai->dl_mask[RX]);
> > +	of_property_read_u32_index(np, "fsl,dl_mask", TX, &sai->dl_mask[TX]);
> +
> >  	irq = platform_get_irq(pdev, 0);
> >  	if (irq < 0) {
> >  		dev_err(&pdev->dev, "no irq for node %s\n", pdev->name);
> diff --git a/sound/soc/fsl/fsl_sai.h b/sound/soc/fsl/fsl_sai.h
> index b1abeed2f78e..6d32f0950ec5 100644
> --- a/sound/soc/fsl/fsl_sai.h
> +++ b/sound/soc/fsl/fsl_sai.h
> @@ -109,8 +109,8 @@
> >  #define FSL_SAI_CR2_DIV_MASK	0xff
>  
>  /* SAI Transmit and Receive Configuration 3 Register */
> > -#define FSL_SAI_CR3_TRCE	BIT(16)
> > -#define FSL_SAI_CR3_TRCE_MASK	GENMASK(16, 23)
> > +#define FSL_SAI_CR3_TRCE(x)	((x) << 16)
> > +#define FSL_SAI_CR3_TRCE_MASK	GENMASK(23, 16)
> >  #define FSL_SAI_CR3_WDFL(x)	(x)
> >  #define FSL_SAI_CR3_WDFL_MASK	0x1f
>  
> @@ -176,6 +176,8 @@ struct fsl_sai {
> >  	unsigned int slots;
> >  	unsigned int slot_width;
>  
> > +	unsigned int dl_mask[2];
> +
> >  	const struct fsl_sai_soc_data *soc_data;
> >  	struct snd_dmaengine_dai_dma_data dma_params_rx;
> >  	struct snd_dmaengine_dai_dma_data dma_params_tx;