Re: [PATCH] soundwire: update Intel BPT message length limitation

[Vinod Koul <vkoul@kernel.org>]

On 29-04-25, 20:23, Bard Liao wrote:
> The limitation of "must be multiples of 32 bytes" does not fit the
> requirement of current Intel platforms. Update it to meet the
> requirement.
> 
> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
> Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
> Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
> ---
>  Documentation/driver-api/soundwire/bra.rst | 2 +-
>  drivers/soundwire/intel_ace2x.c            | 8 ++++----
>  2 files changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/Documentation/driver-api/soundwire/bra.rst b/Documentation/driver-api/soundwire/bra.rst
> index 8500253fa3e8..c08ab2591496 100644
> --- a/Documentation/driver-api/soundwire/bra.rst
> +++ b/Documentation/driver-api/soundwire/bra.rst
> @@ -333,4 +333,4 @@ FIFO sizes to avoid xruns.
>  
>  Alignment requirements are currently not enforced at the core level
>  but at the platform-level, e.g. for Intel the data sizes must be
> -multiples of 32 bytes.
> +equal to or larger than 16 bytes.
> diff --git a/drivers/soundwire/intel_ace2x.c b/drivers/soundwire/intel_ace2x.c
> index 5b31e1f69591..f899c966cfaf 100644
> --- a/drivers/soundwire/intel_ace2x.c
> +++ b/drivers/soundwire/intel_ace2x.c
> @@ -245,7 +245,7 @@ static void intel_ace2x_bpt_close_stream(struct sdw_intel *sdw, struct sdw_slave
>  	cdns->bus.bpt_stream = NULL;
>  }
>  
> -#define INTEL_BPT_MSG_BYTE_ALIGNMENT 32
> +#define INTEL_BPT_MSG_BYTE_MIN 16
>  
>  static int intel_ace2x_bpt_send_async(struct sdw_intel *sdw, struct sdw_slave *slave,
>  				      struct sdw_bpt_msg *msg)
> @@ -253,9 +253,9 @@ static int intel_ace2x_bpt_send_async(struct sdw_intel *sdw, struct sdw_slave *s
>  	struct sdw_cdns *cdns = &sdw->cdns;
>  	int ret;
>  
> -	if (msg->len % INTEL_BPT_MSG_BYTE_ALIGNMENT) {
> -		dev_err(cdns->dev, "BPT message length %d is not a multiple of %d bytes\n",
> -			msg->len, INTEL_BPT_MSG_BYTE_ALIGNMENT);
> +	if (msg->len < INTEL_BPT_MSG_BYTE_MIN) {

Reducing is fine, but we should still check it is aligned..?

> +		dev_err(cdns->dev, "BPT message length %d is less than the minimum bytes %d\n",
> +			msg->len, INTEL_BPT_MSG_BYTE_MIN);
>  		return -EINVAL;
>  	}
>  
> -- 
> 2.43.0

-- 
~Vinod