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[108.49.102.102]) by smtp.gmail.com with ESMTPSA id z187sm97109qkb.129.2021.05.19.09.27.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 19 May 2021 09:27:03 -0700 (PDT) Message-ID: <57b373372cb64e8a48d12e033a23e7711332b0ec.camel@redhat.com> Subject: Re: [PATCH] drm/i915: Force DPCD backlight mode for Samsung 16727 panel From: Lyude Paul Reply-To: lyude@redhat.com To: Aaron Ma , jani.nikula@intel.com, airlied@linux.ie, maarten.lankhorst@linux.intel.com, mripard@kernel.org, daniel@ffwll.ch, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Date: Wed, 19 May 2021 12:27:03 -0400 In-Reply-To: <20210519095305.47133-1-aaron.ma@canonical.com> References: <20210519095305.47133-1-aaron.ma@canonical.com> Organization: Red Hat Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.38.4 (3.38.4-1.fc33) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Seems reasonable to me: Reviewed-by: Lyude Paul On Wed, 2021-05-19 at 17:53 +0800, Aaron Ma wrote: > Another Samsung OLED panel needs DPCD to get control of backlight. > Kernel 5.12+ support the backlight via: > commit: <4a8d79901d5b> ("drm/i915/dp: Enable Intel's HDR backlight interface > (only SDR for now)") > Only make backlight work on lower versions of kernel. > > Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/3474 > Cc: stable@vger.kernel.org # 5.11- > Signed-off-by: Aaron Ma > --- >  drivers/gpu/drm/drm_dp_helper.c | 1 + >  1 file changed, 1 insertion(+) > > diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c > index 5bd0934004e3..7b91d8a76cd6 100644 > --- a/drivers/gpu/drm/drm_dp_helper.c > +++ b/drivers/gpu/drm/drm_dp_helper.c > @@ -1960,6 +1960,7 @@ static const struct edid_quirk edid_quirk_list[] = { >         { MFG(0x4d, 0x10), PROD_ID(0xe6, 0x14), > BIT(DP_QUIRK_FORCE_DPCD_BACKLIGHT) }, >         { MFG(0x4c, 0x83), PROD_ID(0x47, 0x41), > BIT(DP_QUIRK_FORCE_DPCD_BACKLIGHT) }, >         { MFG(0x09, 0xe5), PROD_ID(0xde, 0x08), > BIT(DP_QUIRK_FORCE_DPCD_BACKLIGHT) }, > +       { MFG(0x4c, 0x83), PROD_ID(0x57, 0x41), > BIT(DP_QUIRK_FORCE_DPCD_BACKLIGHT) }, >  }; >   >  #undef MFG -- Sincerely, Lyude Paul (she/her) Software Engineer at Red Hat Note: I deal with a lot of emails and have a lot of bugs on my plate. If you've asked me a question, are waiting for a review/merge on a patch, etc. and I haven't responded in a while, please feel free to send me another email to check on my status. I don't bite!