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Thu, 27 Mar 2025 01:04:58 -0700 (PDT) Date: Thu, 27 Mar 2025 10:04:56 +0200 From: Abel Vesa To: Christopher Obbard Cc: Douglas Anderson , Neil Armstrong , Jessica Zhang , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Bjorn Andersson , Konrad Dybcio , Dmitry Baryshkov , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, Johan Hovold , Rui Miguel Silva , devicetree@vger.kernel.org Subject: Re: [PATCH v2 4/4] drm/dp: fallback to maximum when PWM bit count is zero Message-ID: References: <20250325-wip-obbardc-qcom-t14s-oled-panel-v2-0-e9bc7c9d30cc@linaro.org> <20250325-wip-obbardc-qcom-t14s-oled-panel-v2-4-e9bc7c9d30cc@linaro.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250325-wip-obbardc-qcom-t14s-oled-panel-v2-4-e9bc7c9d30cc@linaro.org> On 25-03-25 19:21:29, Christopher Obbard wrote: > Some eDP devices report DP_EDP_PWMGEN_BIT_COUNT as 0, but still provide > valid non-zero MIN and MAX values. This patch reworks the logic to > fallback to the max value in such cases, ensuring correct backlight PWM > configuration even when the bit count value is not explicitly set. > > This improves compatibility with eDP panels (e.g. Samsung ATNA40YK20 > used on the Lenovo T14s Gen6 Snapdragon with OLED panel) which reports > DP_EDP_PWMGEN_BIT_COUNT as 0 but still provides valid non-zero MIN/MAX > values. > Nit-pick: AFAICT, there is no relationship between this patch and the rest. So it should've probably not be part of this patchset.