From: Ville Syrjälä ville.syrjala@linux.intel.com
commit edca5a2c373db61efa959307c13ed9156b1c14d9 upstream.
Turns out the MIPI sequence block version number and new block size fields are considered part of the block header and are not included in the reported new block size field itself. Bump up the block size appropriately so that we'll copy over the last five bytes of the block as well.
For this particular machine those last five bytes included parts of the GPIO op for the backlight on sequence, causing the backlight no longer to turn back on:
Sequence 6 - MIPI_SEQ_BACKLIGHT_ON Delay: 20000 us - GPIO index 0, number 0, set 0 (0x00) + GPIO index 1, number 70, set 1 (0x01)
Cc: stable@vger.kernel.org Fixes: e163cfb4c96d ("drm/i915/bios: Make copies of VBT data blocks") Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/6652 Signed-off-by: Ville Syrjälä ville.syrjala@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20220829135834.8585-1-ville.sy... Reviewed-by: Jani Nikula jani.nikula@intel.com (cherry picked from commit a06289f3f72431f3777af95ea1226b5b0abdc426) Signed-off-by: Rodrigo Vivi rodrigo.vivi@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/i915/display/intel_bios.c | 7 +++++++ 1 file changed, 7 insertions(+)
--- a/drivers/gpu/drm/i915/display/intel_bios.c +++ b/drivers/gpu/drm/i915/display/intel_bios.c @@ -478,6 +478,13 @@ init_bdb_block(struct drm_i915_private *
block_size = get_blocksize(block);
+ /* + * Version number and new block size are considered + * part of the header for MIPI sequenece block v3+. + */ + if (section_id == BDB_MIPI_SEQUENCE && *(const u8 *)block >= 3) + block_size += 5; + entry = kzalloc(struct_size(entry, data, max(min_size, block_size) + 3), GFP_KERNEL); if (!entry) {