Re: [PATCH v3] drm/bochs: add edid present check

[Oleksandr Andrushchenko]

On 12/20/18 12:51 PM, Daniel Vetter wrote:
> On Thu, Dec 20, 2018 at 11:11:21AM +0100, Gerd Hoffmann wrote:
> > Check header before trying to read the complete edid blob, to avoid the
> > log being spammed in case qemu has no edid support (old qemu or edid
> > support turned off).
> >
> > Fixes: 01f23459cf drm/bochs: add edid support.
> > Signed-off-by: Gerd Hoffmann <kraxel@xxxxxxxxxx>
> Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>
> > ---
> >   drivers/gpu/drm/bochs/bochs_hw.c | 7 +++++++
> >   1 file changed, 7 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/bochs/bochs_hw.c b/drivers/gpu/drm/bochs/bochs_hw.c
> > index c90a0d492f..d0b4e1cee8 100644
> > --- a/drivers/gpu/drm/bochs/bochs_hw.c
> > +++ b/drivers/gpu/drm/bochs/bochs_hw.c
> > @@ -86,9 +86,16 @@ static int bochs_get_edid_block(void *data, u8 *buf,
> >   
> >   int bochs_hw_load_edid(struct bochs_device *bochs)
> >   {
> > +	u8 header[8];
> > +
> >   	if (!bochs->mmio)
> >   		return -1;
> >   
> > +	/* check header to detect whenever edid support is enabled in qemu */
> > +	bochs_get_edid_block(bochs, header, 0, ARRAY_SIZE(header));
> > +	if (drm_edid_header_is_valid(header) != 8)
> > +		return -1;
> > +
> >   	kfree(bochs->edid);
> >   	bochs->edid = drm_do_get_edid(&bochs->connector,
> >   				      bochs_get_edid_block, bochs);
> > --
> > 2.9.3