[PATCH v2] Handle failures in setting a CRTC to a DRM mode properly

[Emil Velikov]

On 26 October 2015 at 10:55, Daniel Martin <consume.noise at gmail.com> wrote:
> On 26 October 2015 at 10:39, Michel Dänzer <michel at daenzer.net> wrote:
>>> diff --git a/src/drmmode_display.c b/src/drmmode_display.c
>>> index 64e79d4..f0f121e 100644
>>> --- a/src/drmmode_display.c
>>> +++ b/src/drmmode_display.c
>>> @@ -760,12 +760,15 @@ drmmode_set_mode_major(xf86CrtcPtr crtc, DisplayModePtr mode,
>>>                               radeon_bo_wait(drmmode_crtc->scanout[0].bo);
>>>                       }
>>>               }
>>> -             ret = drmModeSetCrtc(drmmode->fd, drmmode_crtc->mode_crtc->crtc_id,
>>> -                                  fb_id, x, y, output_ids, output_count, &kmode);
>>> -             if (ret)
>>> +             if (drmModeSetCrtc(drmmode->fd,
>>> +                                drmmode_crtc->mode_crtc->crtc_id,
>>> +                                fb_id, x, y, output_ids,
>>> +                                output_count, &kmode) != 0) {
>>>                       xf86DrvMsg(crtc->scrn->scrnIndex, X_ERROR,
>>>                                  "failed to set mode: %s", strerror(-ret));
>>
>> errno must be passed instead of -ret to strerror. I pushed the patch
>> with that fixed, thanks!
>
> While you're at it, can you add the missing linebreak to the message?
> Just hit it and it looks suspicious:
>     (EE) modeset(0): failed to set mode: Invalid argument(--) RandR disabled
> or
>     (EE) modeset(0): failed to set mode: Invalid argument(II)
> modeset(0): Setting screen physical size to 677 x 381
>
Mildly related:
 - Using -ret opposed to errno -> intel, nouveau, modeset ddx
 - Incorrectly handled failure and missing \n -> modeset ddx

-Emil