Hi All, Some vlv/chv tablets ship with Android as factory OS. The factory OS BSP style kernel on these tablets does not use the normal x86 hw autodetection instead it hardcodes a whole bunch of things including using panel drivers instead of relying on VBT MIPI sequences to turn the panel/backlight on/off. The normal i915 driver (which does not use panel drivers) mostly works since the VBT still needs to contain valid info for the GOP, but because of the Android kernel relying on panel drivers with various things hardcoded some DMI quirks are necessary to fix some issues on these devices. Some of these issues also are related to which I2C bus to use for MIPI sequence elements which do I2C transfers. This series also includes a patch adding some extra debugging to mipi_exec_i2c() to help with debugging similar issues in the future. These patches have been posted before but back then I did not get around to follow up on the series: https://lore.kernel.org/intel-gfx/20220225214934.383168-1-hdegoede@xxxxxxxxxx/ Changes compared to this old version: - Drop the changes how the I2C bus number is found, instead just have the quirks set the right number directly where necessary. This should avoid any chances of causing regressions on devices where the quirks do not apply. - New quirk for backlight control issues on Lenovo Yoga Tab 3 - Address Jani Nikula's remark about __func__ being redundant when using drm_dbg_kms() Regards, Hans Hans de Goede (4): drm/i915/vlv_dsi: Add DMI quirk for wrong panel modeline in BIOS on Asus TF103C (v2) drm/i915/vlv_dsi: Add DMI quirk for wrong I2C bus and panel size on Lenovo Yoga Tablet 2 series (v2) drm/i915/vlv_dsi: Add DMI quirk for backlight control issues on Lenovo Yoga Tab 3 drm/i915/dsi: Add some debug logging to mipi_exec_i2c (v2) drivers/gpu/drm/i915/display/intel_dsi_vbt.c | 3 + drivers/gpu/drm/i915/display/vlv_dsi.c | 124 +++++++++++++++++++ 2 files changed, 127 insertions(+) -- 2.41.0
