From a06289f3f72431f3777af95ea1226b5b0abdc426 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Mon, 29 Aug 2022 16:58:34 +0300 Subject: [PATCH] drm/i915/bios: Copy the whole MIPI sequence block MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Link: https://patchwork.freedesktop.org/patch/msgid/20220829135834.8585-1-ville.syrjala@linux.intel.com Reviewed-by: Jani Nikula --- drivers/gpu/drm/i915/display/intel_bios.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c index 5765643298e1..9c8eecafd625 100644 --- a/drivers/gpu/drm/i915/display/intel_bios.c +++ b/drivers/gpu/drm/i915/display/intel_bios.c @@ -479,6 +479,13 @@ init_bdb_block(struct drm_i915_private *i915, 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) {