From nobody Sun Feb 8 02:56:07 2026 Received: from mail.tuxedocomputers.com (mail.tuxedocomputers.com [157.90.84.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D0BA3264A65 for ; Wed, 21 Jan 2026 22:39:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=157.90.84.7 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769035200; cv=none; b=Z1QV04hs8PxtVuttvogK1rLvFLDLoen6GHxcitq7/Plirgp7gmVh/20K58xcZfWzWEUKeVDmSZqWP6X0Cqle1lbdvLnaOJv3KgXknlylxVmlATJpUSExY1Pfb5ftv0/16lQa5Lx/2bIeQxAHePcC4AJ2rR0YijexD9lWzrOgxCI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769035200; c=relaxed/simple; bh=rCV/mz7IhkXsFCMBrkxc/+ThJfiSDr/73BtYNcwty9Y=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=bHJyrH91VqAG4hG9N4SncYcLBG/VQllhIv2KQ5N2Qo2TJY16p2uPctfYTS2NKP9RXDpCvr2WIK/3jTcP3FW/a67zWA3llfJg5j2OghCzip68BtwrAD59xanpWmm/APwMF5WEdH2G8xjLLGcewtOUh8KpExB7RHjL6M8LVswVDyc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=tuxedocomputers.com; spf=pass smtp.mailfrom=tuxedocomputers.com; dkim=pass (1024-bit key) header.d=tuxedocomputers.com header.i=@tuxedocomputers.com header.b=Cy3im71u; arc=none smtp.client-ip=157.90.84.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=tuxedocomputers.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=tuxedocomputers.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=tuxedocomputers.com header.i=@tuxedocomputers.com header.b="Cy3im71u" Received: from wse-pc.. (unknown [61.8.154.114]) (Authenticated sender: wse@tuxedocomputers.com) by mail.tuxedocomputers.com (Postfix) with ESMTPA id 62D1A2FC0052; Wed, 21 Jan 2026 23:39:46 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tuxedocomputers.com; s=default; t=1769035187; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=hLbZrDz0Hrmb7n202kZRgmxmu9bjINs7CGMfMenSWS0=; b=Cy3im71uXo+asTdc4ajysXLnqB0HgCfHn8UamJhCPnqv9I+x5mkwpT+icagVLeRba4qach LHOaduGfZDZJoOl7zyhSMxXSHAD3Gy+BWvVySRzuGGzcHFWl/B1G88xX0DGMej692M/T7Y NPwg2AHFLyGVJt2smsYC1Cr3lPHbC/I= Authentication-Results: mail.tuxedocomputers.com; auth=pass smtp.auth=wse@tuxedocomputers.com smtp.mailfrom=wse@tuxedocomputers.com From: Werner Sembach To: Jani Nikula , Rodrigo Vivi , Joonas Lahtinen , Tvrtko Ursulin , David Airlie , Simona Vetter Cc: Werner Sembach , intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH v2] drm/i915/display: Add quirk to force backlight type on some TUXEDO devices Date: Wed, 21 Jan 2026 23:38:55 +0100 Message-ID: <20260121223944.1104951-1-wse@tuxedocomputers.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The display backlight on TUXEDO DX1708 and InsanityBook 15 v1 with panels AUO 12701 and AUO 12701 must be forced to INTEL_DP_AUX_BACKLIGHT_ON to be able to control the brightness. This could already be archived via a module parameter, but this patch adds a quirk to apply this by default on the mentioned devices. This patch does not actually test for the exact panels as the id that is used in the intel_dpcd_quirks list is sadly zeroed on the devices, but afaik all these devices use try_intel_interface first anyway so all the quirk does is to add the fallback to try_vesa_interface, so the behaviour on the devices not needing the quirk and fallback should functionally stay the same. Cc: stable@vger.kernel.org Signed-off-by: Werner Sembach --- .../drm/i915/display/intel_dp_aux_backlight.c | 9 ++++++- drivers/gpu/drm/i915/display/intel_quirks.c | 25 ++++++++++++++++++- drivers/gpu/drm/i915/display/intel_quirks.h | 1 + 3 files changed, 33 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/driver= s/gpu/drm/i915/display/intel_dp_aux_backlight.c index 0a3a3f6a5f9d8..bbdfa142d084d 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c @@ -41,6 +41,7 @@ #include "intel_display_types.h" #include "intel_dp.h" #include "intel_dp_aux_backlight.h" +#include "intel_quirks.h" =20 /* * DP AUX registers for Intel's proprietary HDR backlight interface. We de= fine @@ -661,11 +662,17 @@ int intel_dp_aux_init_backlight_funcs(struct intel_co= nnector *connector) struct drm_device *dev =3D connector->base.dev; struct intel_panel *panel =3D &connector->panel; bool try_intel_interface =3D false, try_vesa_interface =3D false; + int enable_dpcd_backlight; =20 /* Check the VBT and user's module parameters to figure out which * interfaces to probe */ - switch (display->params.enable_dpcd_backlight) { + enable_dpcd_backlight =3D display->params.enable_dpcd_backlight; + if (enable_dpcd_backlight =3D=3D INTEL_DP_AUX_BACKLIGHT_AUTO && + intel_has_dpcd_quirk(intel_dp, QUIRK_ENABLE_DPCD_BACKLIGHT)) + enable_dpcd_backlight =3D INTEL_DP_AUX_BACKLIGHT_ON; + + switch (enable_dpcd_backlight) { case INTEL_DP_AUX_BACKLIGHT_OFF: return -ENODEV; case INTEL_DP_AUX_BACKLIGHT_AUTO: diff --git a/drivers/gpu/drm/i915/display/intel_quirks.c b/drivers/gpu/drm/= i915/display/intel_quirks.c index d2e16b79d6be1..df20930f73f75 100644 --- a/drivers/gpu/drm/i915/display/intel_quirks.c +++ b/drivers/gpu/drm/i915/display/intel_quirks.c @@ -86,6 +86,14 @@ static void quirk_edp_limit_rate_hbr2(struct intel_displ= ay *display) drm_info(display->drm, "Applying eDP Limit rate to HBR2 quirk\n"); } =20 +static void quirk_enable_dpcd_backlight(struct intel_dp *intel_dp) +{ + struct intel_display *display =3D to_intel_display(intel_dp); + + intel_set_dpcd_quirk(intel_dp, QUIRK_ENABLE_DPCD_BACKLIGHT); + drm_info(display->drm, "Applying Enable DPCD Backlight quirk\n"); +} + struct intel_quirk { int device; int subsystem_vendor; @@ -251,7 +259,22 @@ static const struct intel_dpcd_quirk intel_dpcd_quirks= [] =3D { .sink_oui =3D SINK_OUI(0x38, 0xec, 0x11), .hook =3D quirk_fw_sync_len, }, - + /* TUXEDO InsanityBook 15 v1 */ + { + .device =3D 0x591b, + .subsystem_vendor =3D 0x1558, + .subsystem_device =3D 0x9501, + .sink_oui =3D SINK_OUI(0x38, 0xec, 0x11), + .hook =3D quirk_enable_dpcd_backlight, + }, + /* TUXEDO DX1708 */ + { + .device =3D 0x3e9b, + .subsystem_vendor =3D 0x1558, + .subsystem_device =3D 0x8500, + .sink_oui =3D SINK_OUI(0x38, 0xec, 0x11), + .hook =3D quirk_enable_dpcd_backlight, + }, }; =20 void intel_init_quirks(struct intel_display *display) diff --git a/drivers/gpu/drm/i915/display/intel_quirks.h b/drivers/gpu/drm/= i915/display/intel_quirks.h index 06da0e286c67c..686f306ab4472 100644 --- a/drivers/gpu/drm/i915/display/intel_quirks.h +++ b/drivers/gpu/drm/i915/display/intel_quirks.h @@ -21,6 +21,7 @@ enum intel_quirk_id { QUIRK_NO_PPS_BACKLIGHT_POWER_HOOK, QUIRK_FW_SYNC_LEN, QUIRK_EDP_LIMIT_RATE_HBR2, + QUIRK_ENABLE_DPCD_BACKLIGHT, }; =20 void intel_init_quirks(struct intel_display *display); --=20 2.43.0