Re: [PATCH 0/2] Match panel hash for overridden mode

Dmitry Baryshkov
2024-02-27T02:26:18Z

On Tue, 27 Feb 2024 at 03:10, Hsin-Yi Wang <hsinyi@chromium.org> wrote:
>
> On Mon, Feb 26, 2024 at 4:37 PM Dmitry Baryshkov
> <dmitry.baryshkov@linaro.org> wrote:
> >
> > On Sat, 24 Feb 2024 at 00:40, Hsin-Yi Wang <hsinyi@chromium.org> wrote:
> > >
> > > This series is a follow up for 1a5e81de180e ("Revert "drm/panel-edp: Add
> > > auo_b116xa3_mode""). It's found that 2 different AUO panels use the same
> > > product id. One of them requires an overridden mode, while the other should
> > > use the mode directly from edid.
> > >
> > > Since product id match is no longer sufficient, EDP_PANEL_ENTRY2 is extended
> > > to check the crc hash of the entire edid base block.
> >
> > Do you have these EDIDs posted somewhere? Can we use something less
> > cryptic than hash for matching the panel, e.g. strings from Monitor
> > Descriptors?
> >
>
> Panel 1:
>
> 00 ff ff ff ff ff ff 00 06 af 5c 40 00 00 00 00
> 00 1a 01 04 95 1a 0e 78 02 99 85 95 55 56 92 28
> 22 50 54 00 00 00 01 01 01 01 01 01 01 01 01 01
> 01 01 01 01 01 01 12 1b 56 5a 50 00 19 30 30 20
> 46 00 00 90 10 00 00 18 00 00 00 0f 00 00 00 00
> 00 00 00 00 00 00 00 00 00 20 00 00 00 fe 00 41
> 55 4f 0a 20 20 20 20 20 20 20 20 20 00 00 00 fe
> 00 42 31 31 36 58 41 4b 30 31 2e 30 20 0a 00 cc
>
> ----------------
>
> Block 0, Base EDID:
> EDID Structure Version & Revision: 1.4
> Vendor & Product Identification:
> Manufacturer: AUO
> Model: 16476
> Made in: 2016
> Basic Display Parameters & Features:
> Digital display
> Bits per primary color channel: 6
> DisplayPort interface
> Maximum image size: 26 cm x 14 cm
> Gamma: 2.20
> Supported color formats: RGB 4:4:4
> First detailed timing includes the native pixel format and
> preferred refresh rate
> Color Characteristics:
> Red : 0.5839, 0.3330
> Green: 0.3378, 0.5712
> Blue : 0.1582, 0.1328
> White: 0.3134, 0.3291
> Established Timings I & II: none
> Standard Timings: none
> Detailed Timing Descriptors:
> DTD 1: 1366x768 60.020 Hz 683:384 47.596 kHz 69.300 MHz
> (256 mm x 144 mm)
> Hfront 48 Hsync 32 Hback 10 Hpol N
> Vfront 4 Vsync 6 Vback 15 Vpol N
> Manufacturer-Specified Display Descriptor (0x0f): 00 0f 00 00 00
> 00 00 00 00 00 00 00 00 00 00 20 '............... '
> Alphanumeric Data String: 'AUO'
> Alphanumeric Data String: 'B116XAK01.0 '
> Checksum: 0xcc
>
>
> Panel 2:
>
> 00 ff ff ff ff ff ff 00 06 af 5c 40 00 00 00 00
> 00 19 01 04 95 1a 0e 78 02 99 85 95 55 56 92 28
> 22 50 54 00 00 00 01 01 01 01 01 01 01 01 01 01
> 01 01 01 01 01 01 ce 1d 56 ea 50 00 1a 30 30 20
> 46 00 00 90 10 00 00 18 d4 17 56 ea 50 00 1a 30
> 30 20 46 00 00 90 10 00 00 18 00 00 00 fe 00 41
> 55 4f 0a 20 20 20 20 20 20 20 20 20 00 00 00 fe
> 00 42 31 31 36 58 41 4e 30 34 2e 30 20 0a 00 94
>
> ----------------
>
> Block 0, Base EDID:
> EDID Structure Version & Revision: 1.4
> Vendor & Product Identification:
> Manufacturer: AUO
> Model: 16476
> Made in: 2015
> Basic Display Parameters & Features:
> Digital display
> Bits per primary color channel: 6
> DisplayPort interface
> Maximum image size: 26 cm x 14 cm
> Gamma: 2.20
> Supported color formats: RGB 4:4:4
> First detailed timing includes the native pixel format and
> preferred refresh rate
> Color Characteristics:
> Red : 0.5839, 0.3330
> Green: 0.3378, 0.5712
> Blue : 0.1582, 0.1328
> White: 0.3134, 0.3291
> Established Timings I & II: none
> Standard Timings: none
> Detailed Timing Descriptors:
> DTD 1: 1366x768 60.059824 Hz 683:384 47.688 kHz
> 76.300000 MHz (256 mm x 144 mm)
> Hfront 48 Hsync 32 Hback 154 Hpol N
> Vfront 4 Vsync 6 Vback 16 Vpol N
> DTD 2: 1366x768 48.016373 Hz 683:384 38.125 kHz
> 61.000000 MHz (256 mm x 144 mm)
> Hfront 48 Hsync 32 Hback 154 Hpol N
> Vfront 4 Vsync 6 Vback 16 Vpol N
> Alphanumeric Data String: 'AUO'
> Alphanumeric Data String: 'B116XAN04.0 '
> Checksum: 0x94
>
> In this example, Descriptors can also be used to distinguish. But it's
> possible that the name field is also reused by mistake, for the same
> reason as model id is reused.

Thank you! Let's settle the discussion at the cover letter.

>
>
> > >
> > > Hsin-Yi Wang (2):
> > > drm_edid: Add a function to get EDID base block
> > > drm/panel: panel-edp: Match with panel hash for overridden modes
> > >
> > > drivers/gpu/drm/drm_edid.c | 55 +++++++++++++++-------------
> > > drivers/gpu/drm/panel/panel-edp.c | 60 ++++++++++++++++++++++++++-----
> > > include/drm/drm_edid.h | 3 +-
> > > 3 files changed, 84 insertions(+), 34 deletions(-)
> > >
> > > --
> > > 2.44.0.rc0.258.g7320e95886-goog
> > >
> >
> >
> > --
> > With best wishes
> > Dmitry

--
With best wishes
Dmitry