From: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Date: Mon, 8 Dec 2025 19:39:25 +0000 (+0100)
Subject: efi: sysfb_efi: Fix efidrmfb and simpledrmfb on Valve Steam Deck
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c7c7eb5ed5a3896e57019f7b33e3b7dcb4ab73b4;p=thirdparty%2Flinux.git

efi: sysfb_efi: Fix efidrmfb and simpledrmfb on Valve Steam Deck

Valve Steam Deck has a 800x1280 portrait screen installed in a landscape
orientation. The firmware offers a software-rotated 1280x800 mode, which
GRUB can be made to switch to when displaying a boot menu. If this mode
was selected frame buffer drivers will see this fake mode and fbcon
rendering will be corrupted.

Let us therefore add a selective quirk inside the current "swap with and
height" handling, which will detect this exact mode and fix it up back to
the native one.

This will allow the DRM-based framebuffer drivers to detect the correct
mode, apply the existing panel orientation quirk, and render the console
in landscape mode with no corruption.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Melissa Wen <mwen@igalia.com>
Cc: linux-efi@vger.kernel.org
Tested-by: Melissa Wen <mwen@igalia.com> # v3
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
[ardb: use local var to refer to screen_info]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---

diff --git a/drivers/firmware/efi/sysfb_efi.c b/drivers/firmware/efi/sysfb_efi.c
index dc4d70b7737c4..aea94a75b575e 100644
--- a/drivers/firmware/efi/sysfb_efi.c
+++ b/drivers/firmware/efi/sysfb_efi.c
@@ -242,6 +242,33 @@ static int __init efifb_swap_width_height(const struct dmi_system_id *id)
 	return 1;
 }
 
+struct efifb_mode_fixup {
+	unsigned int width;
+	unsigned int height;
+	unsigned int linelength;
+};
+
+static int __init
+efifb_check_and_swap_width_height(const struct dmi_system_id *id)
+{
+	const struct efifb_mode_fixup *data = id->driver_data;
+	struct screen_info *si = &screen_info;
+
+	if (data->width == si->lfb_width && data->height == si->lfb_height) {
+		swap(si->lfb_width, si->lfb_height);
+		si->lfb_linelength = data->linelength;
+		si->lfb_size = data->linelength * data->width;
+	}
+
+	return 1;
+}
+
+static const struct efifb_mode_fixup efifb_steamdeck_mode_fixup __initconst = {
+	.width = 1280,
+	.height = 800,
+	.linelength = 3328,
+};
+
 /*
  * Some devices have a portrait LCD but advertise a landscape resolution (and
  * pitch). We simply swap width and height for these devices so that we can
@@ -297,6 +324,26 @@ static const struct dmi_system_id efifb_dmi_swap_width_height[] __initconst = {
 		},
 		.callback = efifb_swap_width_height,
 	},
+	{
+		/* Valve Steam Deck (Jupiter) */
+		.matches = {
+			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Valve"),
+			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Jupiter"),
+			DMI_EXACT_MATCH(DMI_PRODUCT_VERSION, "1"),
+		},
+		.callback = efifb_check_and_swap_width_height,
+		.driver_data = (void *)&efifb_steamdeck_mode_fixup,
+	},
+	{
+		/* Valve Steam Deck (Galileo) */
+		.matches = {
+			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Valve"),
+			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "Galileo"),
+			DMI_EXACT_MATCH(DMI_PRODUCT_VERSION, "1"),
+		},
+		.callback = efifb_check_and_swap_width_height,
+		.driver_data = (void *)&efifb_steamdeck_mode_fixup,
+	},
 	{},
 };