drm/i915/vlv_dsi: Add DMI quirk for backlight control issues on Lenovo Yoga Tab 3...

On the Lenovo Yoga Tab 3 Pro YT3-X90F there are 2 issues with the backlight
on/off MIPI sequences:

1. The backlight on sequence has an I2C MIPI sequence element which uses
   bus 0, but there is a bogus I2cSerialBus resource under the GPU in
   the DSDT which causes i2c_acpi_find_adapter() to pick the wrong bus.

2. There is no backlight off sequence, causing the backlight to stay on.

Add a DMI quirk fixing both issues.

v2:
- Add Closes tag to gitlab issue with drm.debug=0xe, VBT info

Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9380
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230920195613.304091-4-hdegoede@redhat.com

diff --git a/drivers/gpu/drm/i915/display/vlv_dsi.c b/drivers/gpu/drm/i915/display/vlv_dsi.c
index f69cafe8a17d9fcfdd1b994bde35097390770b93..55da627a8b8d222911cd49b1ca18437db2ee4bf4 100644 (file)
--- a/drivers/gpu/drm/i915/display/vlv_dsi.c
+++ b/drivers/gpu/drm/i915/display/vlv_dsi.c
@@ -1805,6 +1805,31 @@ static void vlv_dsi_lenovo_yoga_tab2_size_fixup(struct intel_dsi *intel_dsi)
        }
 }
 
+/*
+ * On the Lenovo Yoga Tab 3 Pro YT3-X90F there are 2 problems:
+ * 1. i2c_acpi_find_adapter() picks the wrong adapter causing mipi_exec_i2c()
+ *    to not work. Fix this by setting i2c_bus_num.
+ * 2. There is no backlight off MIPI sequence, causing the backlight to stay on.
+ *    Add a backlight off sequence mirroring the existing backlight on sequence.
+ *
+ * https://gitlab.freedesktop.org/drm/intel/-/issues/9380
+ */
+static void vlv_dsi_lenovo_yoga_tab3_backlight_fixup(struct intel_dsi *intel_dsi)
+{
+       static const u8 backlight_off_sequence[16] = {
+               /* Header Seq-id 7, length after header 11 bytes */
+               0x07, 0x0b, 0x00, 0x00, 0x00,
+               /* MIPI_SEQ_ELEM_I2C bus 0 addr 0x2c reg 0x00 data-len 1 data 0x00 */
+               0x04, 0x08, 0x00, 0x00, 0x00, 0x2c, 0x00, 0x00, 0x01, 0x00,
+               /* MIPI_SEQ_ELEM_END */
+               0x00
+       };
+       struct intel_connector *connector = intel_dsi->attached_connector;
+
+       intel_dsi->i2c_bus_num = 0;
+       connector->panel.vbt.dsi.sequence[MIPI_SEQ_BACKLIGHT_OFF] = backlight_off_sequence;
+}
+
 static const struct dmi_system_id vlv_dsi_dmi_quirk_table[] = {
        {
                /* Asus Transformer Pad TF103C */
@@ -1828,6 +1853,15 @@ static const struct dmi_system_id vlv_dsi_dmi_quirk_table[] = {
                },
                .driver_data = (void *)vlv_dsi_lenovo_yoga_tab2_size_fixup,
        },
+       {
+               /* Lenovo Yoga Tab 3 Pro YT3-X90F */
+               .matches = {
+                       DMI_MATCH(DMI_SYS_VENDOR, "Intel Corporation"),
+                       DMI_MATCH(DMI_PRODUCT_NAME, "CHERRYVIEW D1 PLATFORM"),
+                       DMI_MATCH(DMI_PRODUCT_VERSION, "Blade3-10A-001"),
+               },
+               .driver_data = (void *)vlv_dsi_lenovo_yoga_tab3_backlight_fixup,
+       },
        { }
 };