From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 43C981D5CC2; Mon, 31 Mar 2025 07:50:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743407422; cv=none; b=MZsYuTzu9cbQq9KixQ2AvKNbZRBhm24/hM/UDnEBf95soEFDhUnIMIPa4HJ8e0OagCNe8lZ6GHAg0nYrPbbDGA0jtQxWaZPca/KUMX4jL1iZyvsI7F+acWGzyFhnhhluxw+5UqvLlXpZrwPqcGSUocUxEY3pmMQ+XHhCX9ly+W4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743407422; c=relaxed/simple; bh=prYw5u8aOVdWtVy6m/f9wz2b6yIFj/X4vl/CDi7qjyQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=lL+PzlE3Mb4zuHHfiEyUWIud+aRx5CvFSPZyG/H1+VEC6s9f8nA+zO/y6ELlihf/Zu41WeRX3t7H6nLK06jxjPuqPihdQuMypby4Ik9E4+zikp5DkCKOR2nVh5peMm120nvQybpUhL+zHc5vZiCqnhSnVEEarpOJpUOBBhPVXKA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AM/pd9GY; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="AM/pd9GY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A6366C4CEE3; Mon, 31 Mar 2025 07:50:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743407421; bh=prYw5u8aOVdWtVy6m/f9wz2b6yIFj/X4vl/CDi7qjyQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=AM/pd9GYteRQlJHH/4X+M0M8nhgTeNEfVSpqgsbbU5wiwkmMPlyVTd8bLxqEmRFPA 4lcFyj0NdCqddz2tPlng2UW+ZkqHQ7ft6RKN6Z8NrjawnLDfNbDzz1JbEk+001y7bW cgz0/f3YJRN3QfcvpffdtzpVomt7JntgcUSbeUC1xR2cRLZWAqujDuzFtGpNiAeW3Q mXLrwE6TxaxDk6h3898Tk1UBLaqBFOCIJdKn/5URXjlXyMdmmuqxrmfp6TMfo5GT1b PPHYRRdy/ZucFP7tgDqFLY+5hTH28fwsLQm4Z48NUkMwPNya62eDQzlpFRTCd9P0OW JKlXVaiCG+0Eg== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1tz9uZ-00000000574-2xYS; Mon, 31 Mar 2025 09:50:23 +0200 Date: Mon, 31 Mar 2025 09:50:23 +0200 From: Johan Hovold 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, Rui Miguel Silva , Abel Vesa , devicetree@vger.kernel.org, Bryan O'Donoghue Subject: Re: [PATCH v3 1/2] arm64: dts: qcom: x1e78100-t14s: add hpd gpio to eDP panel Message-ID: References: <20250327-wip-obbardc-qcom-t14s-oled-panel-v3-0-45d5f2747398@linaro.org> <20250327-wip-obbardc-qcom-t14s-oled-panel-v3-1-45d5f2747398@linaro.org> Precedence: bulk X-Mailing-List: devicetree@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: <20250327-wip-obbardc-qcom-t14s-oled-panel-v3-1-45d5f2747398@linaro.org> On Thu, Mar 27, 2025 at 04:56:53PM +0000, Christopher Obbard wrote: > The eDP panel has an HPD GPIO. Describe it in the device tree > for the generic T14s model, as the HPD GPIO property is used in > both the OLED and LCD models which inherit this device tree. AFAICT, this patch is not correct as the hotplug detect signal is connected directly to the display controller on (these) Qualcomm SoCs and is already handled by its driver. Describing it as you do here leads to less accurate delays, see commits: 2327b13d6c47 ("drm/panel-edp: Take advantage of wait_hpd_asserted() in struct drm_dp_aux"). 3b5765df375c ("drm/panel: atna33xc20: Take advantage of wait_hpd_asserted() in struct drm_dp_aux") Perhaps you lose some other functionality too. > Reviewed-by: Bryan O'Donoghue > Signed-off-by: Christopher Obbard > --- > arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi b/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi > index 962fb050c55c4fd33f480a21a8c47a484d0c82b8..46c73f5c039ed982b553636cf8c4237a20ba7687 100644 > --- a/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi > +++ b/arch/arm64/boot/dts/qcom/x1e78100-lenovo-thinkpad-t14s.dtsi > @@ -980,8 +980,12 @@ &mdss_dp3 { > aux-bus { > panel: panel { > compatible = "edp-panel"; > + hpd-gpios = <&tlmm 119 GPIO_ACTIVE_HIGH>; > power-supply = <&vreg_edp_3p3>; > > + pinctrl-0 = <&edp_hpd_n_default>; > + pinctrl-names = "default"; > + > port { > edp_panel_in: endpoint { > remote-endpoint = <&mdss_dp3_out>; > @@ -1286,6 +1290,13 @@ hall_int_n_default: hall-int-n-state { > bias-disable; > }; > > + edp_hpd_n_default: edp-hpd-n-state { > + pins = "gpio119"; > + function = "gpio"; > + drive-strength = <2>; > + bias-pull-up; > + }; I checked the firmware configuration for this pin on my T14s, which does not match what you have here. Instead the function is set to "edp0_hot" which forwards the signal to the display controller which already handles the signal on panel power on. (And there is also no internal pull up enabled). We may want to describe this pin configuration somewhere, but that's a separate issue. Johan