From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= Date: Fri, 27 Mar 2020 12:56:26 +0000 Subject: Re: [Intel-gfx] [PATCH v7 05/18] video/hdmi: Add Unpack only function for DRM infoframe Message-Id: <20200327125626.GE13686@intel.com> List-Id: References: <20200211074657.231405-1-gwan-gyeong.mun@intel.com> <20200211074657.231405-6-gwan-gyeong.mun@intel.com> <87k13fcm8w.fsf@intel.com> <87h7yjcldq.fsf@intel.com> <20200320115737.GF5193@pendragon.ideasonboard.com> <2dd87897a2c1dea8d882141823ed1ca1206ec01c.camel@intel.com> In-Reply-To: <2dd87897a2c1dea8d882141823ed1ca1206ec01c.camel@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: "Mun, Gwan-gyeong" Cc: "linux-fbdev@vger.kernel.org" , "b.zolnierkie@samsung.com" , "intel-gfx@lists.freedesktop.org" , "dri-devel@lists.freedesktop.org" , "hverkuil@xs4all.nl" , "laurent.pinchart@ideasonboard.com" On Fri, Mar 27, 2020 at 07:27:56AM +0000, Mun, Gwan-gyeong wrote: > On Fri, 2020-03-20 at 13:57 +0200, Laurent Pinchart wrote: > > Hi Jani, > >=20 > > On Fri, Mar 20, 2020 at 01:32:17PM +0200, Jani Nikula wrote: > > > On Fri, 20 Mar 2020, Jani Nikula > > > wrote: > > > > On Tue, 11 Feb 2020, Gwan-gyeong Mun > > > > wrote: > > > > > It adds an unpack only function for DRM infoframe for dynamic > > > > > range and > > > > > mastering infoframe readout. > > > > > It unpacks the information data block contained in the binary > > > > > buffer into > > > > > a structured frame of the HDMI Dynamic Range and Mastering > > > > > (DRM) > > > > > information frame. > > > > >=20 > > > > > In contrast to hdmi_drm_infoframe_unpack() function, it does > > > > > not verify > > > > > a checksum. > > > > >=20 > > > > > It can be used for unpacking a DP HDR Metadata Infoframe SDP > > > > > case. > > > > > DP HDR Metadata Infoframe SDP uses the same Dynamic Range and > > > > > Mastering > > > > > (DRM) information (CTA-861-G spec.) such as HDMI DRM infoframe. > > > > > But DP SDP header and payload structure are different from HDMI > > > > > DRM > > > > > Infoframe. Therefore unpacking DRM infoframe for DP requires > > > > > skipping of > > > > > a verifying checksum. > > > > >=20 > > > > > Signed-off-by: Gwan-gyeong Mun > > > > > Reviewed-by: Uma Shankar > > > >=20 > > > > Bartlomiej, can I have your ack for merging this via drm-intel > > > > along > > > > with the rest of the series, please? > > >=20 > > > Or Hans or Laurent, from v4l/video point of view. > >=20 > > I'm no expert on InfoFrame, I'll only comment on the API below. > >=20 > > > > > --- > > > > > drivers/video/hdmi.c | 58 +++++++++++++++++++++++++++++++----- > > > > > -------- > > > > > include/linux/hdmi.h | 2 ++ > > > > > 2 files changed, 43 insertions(+), 17 deletions(-) > > > > >=20 > > > > > diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c > > > > > index 9c82e2a0a411..9818836d82b7 100644 > > > > > --- a/drivers/video/hdmi.c > > > > > +++ b/drivers/video/hdmi.c > > > > > @@ -1775,20 +1775,18 @@ hdmi_vendor_any_infoframe_unpack(union > > > > > hdmi_vendor_any_infoframe *frame, > > > > > } > > > > > =20 > > > > > /** > > > > > - * hdmi_drm_infoframe_unpack() - unpack binary buffer to a > > > > > HDMI DRM infoframe > > > > > + * hdmi_drm_infoframe_unpack_only() - unpack binary buffer to > > > > > a HDMI DRM infoframe > > > > > * @frame: HDMI DRM infoframe > > > > > * @buffer: source buffer > > > > > * @size: size of buffer > > > > > * > > > > > - * Unpacks the information contained in binary @buffer into a > > > > > structured > > > > > + * Unpacks the information data block contained in binary > > > > > @buffer into a structured > >=20 > > Line wrap please. > >=20 > > This needs to be clarified to explain exactly what the buffer points > > to. > >=20 > Okay I'll update clear comments next version. > > Also, as this is applicable to DP too, shouldn't we drop the hdmi_ > > prefix ? Is there another prefix that could be used for functions > > that > > are application to infoframe handling shared by different display > > interfaces ? A bit of refactoring would help making all this clear. > >=20 > Both DP and HDMI use CTA-861-G spec for DRM infoframe. I'll update > prefix with cta_ instead of hdmi_. Most of video/hdmi.c is from the CTA spec(s). The name is just a name. Let's not start making it inconsistent just for this one case. --=20 Ville Syrj=E4l=E4 Intel