On Wed, 04 May 2022, Andrzej Hajda <andrzej.hajda@xxxxxxxxx> wrote:
> On some configurations drm_fb_helper_initial_config sometimes fails.
> Logging error value should help debugging such issues.
>
> Signed-off-by: Andrzej Hajda <andrzej.hajda@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/display/intel_fbdev.c | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_fbdev.c b/drivers/gpu/drm/i915/display/intel_fbdev.c
> index 221336178991f0..557c7f15ac22a9 100644
> --- a/drivers/gpu/drm/i915/display/intel_fbdev.c
> +++ b/drivers/gpu/drm/i915/display/intel_fbdev.c
> @@ -539,11 +539,16 @@ int intel_fbdev_init(struct drm_device *dev)
> static void intel_fbdev_initial_config(void *data, async_cookie_t cookie)
> {
> struct intel_fbdev *ifbdev = data;
> + int ret;
>
> /* Due to peculiar init order wrt to hpd handling this is separate. */
> - if (drm_fb_helper_initial_config(&ifbdev->helper,
> - ifbdev->preferred_bpp))
> - intel_fbdev_unregister(to_i915(ifbdev->helper.dev));
> + ret = drm_fb_helper_initial_config(&ifbdev->helper,
> + ifbdev->preferred_bpp);
> + if (!ret)
> + return;
If this patch is intended for merging, I'd prefer keeping the failure
path indented within if (ret).
> + drm_err(ifbdev->helper.dev, "failed to set initial configuration: %pe\n",
> + ERR_PTR(ret));
I'm leaning towards preferring "%s", errname(ret) over "%pe",
ERR_PTR(ret) because everyone knows what %s means and using ERR_PTR()
seems odd when it's really a plain int.
BR,
Jani.
> + intel_fbdev_unregister(to_i915(ifbdev->helper.dev));
> }
>
> void intel_fbdev_initial_config_async(struct drm_device *dev)
--
Jani Nikula, Intel Open Source Graphics Center
