[PATCH] drm: panel-backlight-quirks: Add ASUS ROG Flow Z13 (GZ302)

[aic0d3r <igotmysoul@gmail.com>]

The firmware (ATIF) minimum backlight on the 2025 ASUS ROG Flow Z13
(GZ302, Strix Halo) with its TMA 0x0803 panel is fairly bright: at the
lowest brightness level actual_brightness reads 539 of 65535, which is
uncomfortable in a dark room.

Lower min_input_signal to 1 via a min_brightness quirk. With it the
lowest level reads back 0 and the panel is still lit and readable, so
the usable range extends noticeably below the firmware floor.

Match on the product family rather than the product name, since the
product name carries the SKU ("ROG Flow Z13 GZ302EA_GZ302EA"), and on the
panel ID so other panels in the family are unaffected.

Tested on a GZ302EA with BIOS GZ302EA.314 on 7.3.1.

Signed-off-by: aic0d3r <igotmysoul@gmail.com>
---
 drivers/gpu/drm/drm_panel_backlight_quirks.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/drm_panel_backlight_quirks.c b/drivers/gpu/drm/drm_panel_backlight_quirks.c
index dcb91e12b..fa5897bb2 100644
--- a/drivers/gpu/drm/drm_panel_backlight_quirks.c
+++ b/drivers/gpu/drm/drm_panel_backlight_quirks.c
@@ -68,6 +68,15 @@ static const struct drm_get_panel_backlight_quirk drm_panel_min_backlight_quirks
 		.dmi_match_other.value = "Galileo",
 		.quirk = { .min_brightness = 1, },
 	},
+	/* ASUS ROG Flow Z13 (2025, GZ302) */
+	{
+		.dmi_match.field = DMI_SYS_VENDOR,
+		.dmi_match.value = "ASUSTeK COMPUTER INC.",
+		.dmi_match_other.field = DMI_PRODUCT_FAMILY,
+		.dmi_match_other.value = "ROG Flow Z13",
+		.ident.panel_id = drm_edid_encode_panel_id('T', 'M', 'A', 0x0803),
+		.quirk = { .min_brightness = 2, },
+	},
 	/* Have OLED Panels with brightness issue when last byte is 0/1 */
 	{
 		.dmi_match.field = DMI_SYS_VENDOR,
-- 
2.56.0