Re: [PATCH] drm: fixes crct set_mode when encoder mode_fixup is null.

On Wed, Feb 10, 2016 at 12:15:22PM +0000, Carlos Palminha wrote:

Avoids null crash when encoders don't implement mode_fixup.

Signed-off-by: Carlos Palminha palminha@synopsys.com

drivers/gpu/drm/drm_crtc_helper.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c index a02a7f9..ef3def7 100644 --- a/drivers/gpu/drm/drm_crtc_helper.c +++ b/drivers/gpu/drm/drm_crtc_helper.c @@ -328,10 +328,12 @@ bool drm_crtc_helper_set_mode(struct drm_crtc *crtc, }

encoder_funcs = encoder->helper_private;

• if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
  

• 				      adjusted_mode))) {
  

• 	DRM_DEBUG_KMS("Encoder fixup failed\n");
  

• 	goto done;
  

• if (encoder_funcs->mode_fixup) {
  

• 	if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
  

• 					      adjusted_mode))) {
  

• 		DRM_DEBUG_KMS("Encoder fixup failed\n");
  

• 		goto done;
  

• 	}
  

At first I thought this isn't useful since it's the old legacy helper code that no new driver should use. But from a quick

$ git grep mode_fixup.*encoder

it looks like there's piles of existing drivers that could benefit from this with a small cleanup. So applied it, but can you pls follow up with patches to get rid of the now unecessary dummy functions?

Thanks, Daniel

}

}

-- 2.5.0