[Intel-gfx] [PATCH 1/2] drm/edid: Add and export function to parse manufacturer id

[Jani Nikula]

On Thu, 08 Nov 2018, Daniel Vetter <daniel at ffwll.ch> wrote:
> On Thu, Nov 08, 2018 at 08:42:52PM +0000, Souza, Jose wrote:
>> On Thu, 2018-11-08 at 09:31 +0100, Daniel Vetter wrote:
>> > On Wed, Nov 07, 2018 at 04:23:52PM -0800, José Roberto de Souza
>> > wrote:
>> > > This function will be helpful to drivers that wants to add its own
>> > > quirks to sinks.
>> > 
>> > Why would you want to do that? The point of a shared edid parsing
>> > code is
>> > that we can share all these quirks ...
>> > 
>> > For these kind of patches, always include the driver code that makes
>> > use
>> > of your new code too. That makes it much easier to answer these
>> > questions.
>> 
>> This will be used to disable or enable with quirks PSR in some panels
>> that do not behave like eDP spec states.
>> As this would be specifc to i915, I guess is better keep the list only
>> in i915.
>> 
>> What is your opinion about that?
>
> For anything dp, shouldn't we use the OUI instead? Or is that more garbage
> than the EDID serial?

The OUI isn't always present, but we can use it when it is. And we
already have DPCD quirk support for that in drm_dp_helper.c.

> And yes, psr quirking for i915 seems like a reasonable thing to do, using
> either approach. But definitely include the full picture, including i915
> patches, in your next round.

I think all of the quirk matching should be in drm core or helpers. For
most quirks, it's up to the drivers to actually do something with that
information anyway, so it'll still remain i915 specific.

BR,
Jani.




> -Daniel
>
>> 
>> > 
>> > Thanks, Daniel
>> > 
>> > 
>> > > Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
>> > > ---
>> > >  drivers/gpu/drm/drm_edid.c | 20 ++++++++++++++++----
>> > >  include/drm/drm_edid.h     |  1 +
>> > >  2 files changed, 17 insertions(+), 4 deletions(-)
>> > > 
>> > > diff --git a/drivers/gpu/drm/drm_edid.c
>> > > b/drivers/gpu/drm/drm_edid.c
>> > > index b506e3622b08..1a0ddf3d326b 100644
>> > > --- a/drivers/gpu/drm/drm_edid.c
>> > > +++ b/drivers/gpu/drm/drm_edid.c
>> > > @@ -1755,6 +1755,21 @@ EXPORT_SYMBOL(drm_edid_duplicate);
>> > >  
>> > >  /*** EDID parsing ***/
>> > >  
>> > > +/**
>> > > + * drm_edid_manufacturer_parse - parse the EDID manufacturer id to
>> > > readable
>> > > + * characters and set into manufacturer parameter.
>> > > + * @edid: EDID to get the manufacturer
>> > > + * @manufacturer: the char buffer to store the id
>> > > + */
>> > > +void drm_edid_manufacturer_parse(const struct edid *edid, char
>> > > manufacturer[3])
>> > > +{
>> > > +	manufacturer[0] = ((edid->mfg_id[0] & 0x7c) >> 2) + '@';
>> > > +	manufacturer[1] = (((edid->mfg_id[0] & 0x3) << 3) |
>> > > +			  ((edid->mfg_id[1] & 0xe0) >> 5)) + '@';
>> > > +	manufacturer[2] = (edid->mfg_id[1] & 0x1f) + '@';
>> > > +}
>> > > +EXPORT_SYMBOL(drm_edid_manufacturer_parse);
>> > > +
>> > >  /**
>> > >   * edid_vendor - match a string against EDID's obfuscated vendor
>> > > field
>> > >   * @edid: EDID to match
>> > > @@ -1766,10 +1781,7 @@ static bool edid_vendor(const struct edid
>> > > *edid, const char *vendor)
>> > >  {
>> > >  	char edid_vendor[3];
>> > >  
>> > > -	edid_vendor[0] = ((edid->mfg_id[0] & 0x7c) >> 2) + '@';
>> > > -	edid_vendor[1] = (((edid->mfg_id[0] & 0x3) << 3) |
>> > > -			  ((edid->mfg_id[1] & 0xe0) >> 5)) + '@';
>> > > -	edid_vendor[2] = (edid->mfg_id[1] & 0x1f) + '@';
>> > > +	drm_edid_manufacturer_parse(edid, edid_vendor);
>> > >  
>> > >  	return !strncmp(edid_vendor, vendor, 3);
>> > >  }
>> > > diff --git a/include/drm/drm_edid.h b/include/drm/drm_edid.h
>> > > index e3c404833115..e4f3f7f34d6a 100644
>> > > --- a/include/drm/drm_edid.h
>> > > +++ b/include/drm/drm_edid.h
>> > > @@ -466,6 +466,7 @@ struct edid *drm_get_edid_switcheroo(struct
>> > > drm_connector *connector,
>> > >  				     struct i2c_adapter *adapter);
>> > >  struct edid *drm_edid_duplicate(const struct edid *edid);
>> > >  int drm_add_edid_modes(struct drm_connector *connector, struct
>> > > edid *edid);
>> > > +void drm_edid_manufacturer_parse(const struct edid *edid, char
>> > > manufacturer[3]);
>> > >  
>> > >  u8 drm_match_cea_mode(const struct drm_display_mode *to_match);
>> > >  enum hdmi_picture_aspect drm_get_cea_aspect_ratio(const u8
>> > > video_code);
>> > > -- 
>> > > 2.19.1
>> > > 
>> > > _______________________________________________
>> > > Intel-gfx mailing list
>> > > Intel-gfx at lists.freedesktop.org
>> > > https://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Jani Nikula, Intel Open Source Graphics Center