Re: [PATCH v1] coresight: tpda: fix the logic to setup the element size

[James Clark <james.clark@linaro.org>]

On 06/08/2025 9:09 am, Jie Gan wrote:
> Some TPDM devices support both CMB and DSB datasets, requiring
> the system to enable the port with both corresponding element sizes.
> 
> Currently, the logic treats tpdm_read_element_size as successful if
> the CMB element size is retrieved correctly, regardless of whether
> the DSB element size is obtained. This behavior causes issues
> when parsing data from TPDM devices that depend on both element sizes.
> 
> To address this, the function should explicitly fail if the DSB
> element size cannot be read correctly.
> 
> Fixes: e6d7f5252f73 ("coresight-tpda: Add support to configure CMB element")
> Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
> ---
>   drivers/hwtracing/coresight/coresight-tpda.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-tpda.c b/drivers/hwtracing/coresight/coresight-tpda.c
> index 0633f04beb24..333b3cb23685 100644
> --- a/drivers/hwtracing/coresight/coresight-tpda.c
> +++ b/drivers/hwtracing/coresight/coresight-tpda.c
> @@ -71,6 +71,8 @@ static int tpdm_read_element_size(struct tpda_drvdata *drvdata,
>   	if (tpdm_data->dsb) {
>   		rc = fwnode_property_read_u32(dev_fwnode(csdev->dev.parent),
>   				"qcom,dsb-element-bits", &drvdata->dsb_esize);
> +		if (rc)
> +			goto out;
>   	}
>   
>   	if (tpdm_data->cmb) {
> @@ -78,6 +80,7 @@ static int tpdm_read_element_size(struct tpda_drvdata *drvdata,
>   				"qcom,cmb-element-bits", &drvdata->cmb_esize);
>   	}
>   
> +out:
>   	if (rc)
>   		dev_warn_once(&csdev->dev,
>   			"Failed to read TPDM Element size: %d\n", rc);

Reviewed-by: James Clark <james.clark@linaro.org>