Re: [PATCH] drm: dpcd: Print more useful information during error

From: Jani Nikula
Date: Tue Apr 14 2020 - 07:04:21 EST


On Thu, 09 Apr 2020, Aurabindo Pillai <mail@xxxxxxxxxxxx> wrote:
> When DPCD access errors occur, knowing the register and request
> associated with the error helps debugging, so print the
> details in the debug message.
>
> Signed-off-by: Aurabindo Pillai <mail@xxxxxxxxxxxx>
> ---
> drivers/gpu/drm/drm_dp_helper.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
> index a5364b519..545606aac 100644
> --- a/drivers/gpu/drm/drm_dp_helper.c
> +++ b/drivers/gpu/drm/drm_dp_helper.c
> @@ -257,7 +257,9 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 request,
> err = ret;
> }
>
> - DRM_DEBUG_KMS("Too many retries, giving up. First error: %d\n", err);
> + DRM_DEBUG_KMS("dpcd: Too many retries, giving up. First error: %d\t"
> + "address: %x\trequest: %x\t size:%zu\n",
> + err, msg.address, msg.request, msg.size);

Nitpicks, please don't add tabs, maybe use commas instead, and please
add 0x in front of hex.

BR,
Jani.


> ret = err;
>
> unlock:

--
Jani Nikula, Intel Open Source Graphics Center