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 E55C11662F1; Sun, 26 Jan 2025 14:53:16 +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=1737903197; cv=none; b=bF9x2mWgohFiMH6sGQaeJJEiDl4tDgLkGSoFZIEEDG+lRty09fxCPVMRcwpylVX6icPMICtT3/g83DOwKj4zFMbKMFaSE/PkG4oP+4yF6icVDMTm6MNsoqwJtUIz5bNAabf7ZmhRyQYKGBXGZmfhyyqw6Wj/4Sbkv5qdi3JmL+E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737903197; c=relaxed/simple; bh=+ECe4fzrYv0SET9Ee7tX8FTwbNt/UaWzPa4F/8JTmus=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=R683C8DXBHcLc9ppVAM5kbTnFeOLKcWW9lgpqkLogczc/jFj4DhxCPvd3A7XvADC3b/XhwTNAOIeTKyGU0wcz47eSwtlEELXZyHwVc9JY6bF1QST5RIPxY2gfCq/cu4AbTl1sAJJ/aA3epyi8IlP5ipBtJNIJ0SvYTbFJcmVfbk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pIkZQ86D; 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="pIkZQ86D" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BECB6C4CEE8; Sun, 26 Jan 2025 14:53:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1737903196; bh=+ECe4fzrYv0SET9Ee7tX8FTwbNt/UaWzPa4F/8JTmus=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pIkZQ86DKb+qTe3HhTE/vYh7r3DYDlqOAPkR8qemYaJGE+PhFZBOJvWsjzJ0OIEHn Cm09jL3jLLoGhS+yKPpzx3hUT6QkoVc0RL1vvcic+gdZFTwbnYnwPjmqwpHOUE2Vav hPNSmtJefnlBNhomGf1BP0Mn3v/XWE0HoIVTj6v4li26yHukKueDzlUmLeBMP4VPmw yPyxG49ztK86a3GPncIR4fHWKACLuj6knu1aCHRaqp9/7hZV0n3FNZTwHhRND89JfN Y9ZTkdQYG1hp2o0Mau1M9hyXs+WsDHXZgCuS2vi+FMdPZC1Y/8bKozUBMvRpv/01b9 sS8NBgxSinOgA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= , "Dustin L . Howett" , Mario Limonciello , Harry Wentland , Sasha Levin , airlied@gmail.com, simona@ffwll.ch, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, corbet@lwn.net, dri-devel@lists.freedesktop.org, linux-doc@vger.kernel.org Subject: [PATCH AUTOSEL 6.13 02/34] drm: Add panel backlight quirks Date: Sun, 26 Jan 2025 09:52:38 -0500 Message-Id: <20250126145310.926311-2-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250126145310.926311-1-sashal@kernel.org> References: <20250126145310.926311-1-sashal@kernel.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=UTF-8 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.13 Content-Transfer-Encoding: 8bit From: Thomas Weißschuh [ Upstream commit 22e5c7ae12145af13785e3ff138395d5b1a22116 ] Panels using a PWM-controlled backlight source do not have a standard way to communicate their valid PWM ranges. On x86 the ranges are read from ACPI through driver-specific tables. The built-in ranges are not necessarily correct, or may grow stale if an older device can be retrofitted with newer panels. Add a quirk infrastructure with which the minimum valid backlight value can be maintained as part of the kernel. Signed-off-by: Thomas Weißschuh Tested-by: Dustin L. Howett Reviewed-by: Mario Limonciello Reviewed-by: Harry Wentland Signed-off-by: Mario Limonciello Link: https://patchwork.freedesktop.org/patch/msgid/20241111-amdgpu-min-backlight-quirk-v7-1-f662851fda69@weissschuh.net Signed-off-by: Sasha Levin --- Documentation/gpu/drm-kms-helpers.rst | 3 + drivers/gpu/drm/Kconfig | 4 ++ drivers/gpu/drm/Makefile | 1 + drivers/gpu/drm/drm_panel_backlight_quirks.c | 70 ++++++++++++++++++++ include/drm/drm_utils.h | 4 ++ 5 files changed, 82 insertions(+) create mode 100644 drivers/gpu/drm/drm_panel_backlight_quirks.c diff --git a/Documentation/gpu/drm-kms-helpers.rst b/Documentation/gpu/drm-kms-helpers.rst index 8cf2f041af470..b4ee25af1702b 100644 --- a/Documentation/gpu/drm-kms-helpers.rst +++ b/Documentation/gpu/drm-kms-helpers.rst @@ -221,6 +221,9 @@ Panel Helper Reference .. kernel-doc:: drivers/gpu/drm/drm_panel_orientation_quirks.c :export: +.. kernel-doc:: drivers/gpu/drm/drm_panel_backlight_quirks.c + :export: + Panel Self Refresh Helper Reference =================================== diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index 772fc7625639d..b55be8889e2ca 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -530,6 +530,10 @@ config DRM_HYPERV config DRM_EXPORT_FOR_TESTS bool +# Separate option as not all DRM drivers use it +config DRM_PANEL_BACKLIGHT_QUIRKS + tristate + config DRM_LIB_RANDOM bool default n diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index 463afad1b5ca6..06b73068d2483 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -95,6 +95,7 @@ drm-$(CONFIG_DRM_PANIC_SCREEN_QR_CODE) += drm_panic_qr.o obj-$(CONFIG_DRM) += drm.o obj-$(CONFIG_DRM_PANEL_ORIENTATION_QUIRKS) += drm_panel_orientation_quirks.o +obj-$(CONFIG_DRM_PANEL_BACKLIGHT_QUIRKS) += drm_panel_backlight_quirks.o # # Memory-management helpers diff --git a/drivers/gpu/drm/drm_panel_backlight_quirks.c b/drivers/gpu/drm/drm_panel_backlight_quirks.c new file mode 100644 index 0000000000000..6b8bbed77c7f1 --- /dev/null +++ b/drivers/gpu/drm/drm_panel_backlight_quirks.c @@ -0,0 +1,70 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include +#include +#include + +struct drm_panel_min_backlight_quirk { + struct { + enum dmi_field field; + const char * const value; + } dmi_match; + struct drm_edid_ident ident; + u8 min_brightness; +}; + +static const struct drm_panel_min_backlight_quirk drm_panel_min_backlight_quirks[] = { +}; + +static bool drm_panel_min_backlight_quirk_matches(const struct drm_panel_min_backlight_quirk *quirk, + const struct drm_edid *edid) +{ + if (!dmi_match(quirk->dmi_match.field, quirk->dmi_match.value)) + return false; + + if (!drm_edid_match(edid, &quirk->ident)) + return false; + + return true; +} + +/** + * drm_get_panel_min_brightness_quirk - Get minimum supported brightness level for a panel. + * @edid: EDID of the panel to check + * + * This function checks for platform specific (e.g. DMI based) quirks + * providing info on the minimum backlight brightness for systems where this + * cannot be probed correctly from the hard-/firm-ware. + * + * Returns: + * A negative error value or + * an override value in the range [0, 255] representing 0-100% to be scaled to + * the drivers target range. + */ +int drm_get_panel_min_brightness_quirk(const struct drm_edid *edid) +{ + const struct drm_panel_min_backlight_quirk *quirk; + size_t i; + + if (!IS_ENABLED(CONFIG_DMI)) + return -ENODATA; + + if (!edid) + return -EINVAL; + + for (i = 0; i < ARRAY_SIZE(drm_panel_min_backlight_quirks); i++) { + quirk = &drm_panel_min_backlight_quirks[i]; + + if (drm_panel_min_backlight_quirk_matches(quirk, edid)) + return quirk->min_brightness; + } + + return -ENODATA; +} +EXPORT_SYMBOL(drm_get_panel_min_brightness_quirk); + +MODULE_DESCRIPTION("Quirks for panel backlight overrides"); +MODULE_LICENSE("GPL"); diff --git a/include/drm/drm_utils.h b/include/drm/drm_utils.h index 70775748d243b..15fa9b6865f44 100644 --- a/include/drm/drm_utils.h +++ b/include/drm/drm_utils.h @@ -12,8 +12,12 @@ #include +struct drm_edid; + int drm_get_panel_orientation_quirk(int width, int height); +int drm_get_panel_min_brightness_quirk(const struct drm_edid *edid); + signed long drm_timeout_abs_to_jiffies(int64_t timeout_nsec); #endif -- 2.39.5