diff options
author | Lukasz Majczak <lma@semihalf.com> | 2021-09-30 15:46:06 +0200 |
---|---|---|
committer | Jani Nikula <jani.nikula@intel.com> | 2021-10-05 11:52:48 +0300 |
commit | fdddf8c3a477f77b3a623f220e78d45e89fc50d5 (patch) | |
tree | 8705aaa68316629ea9eddaebbfcba99dba1215ec /drivers/gpu | |
parent | a532cde31de3cae6ed60e60d6f9379771f652809 (diff) |
drm/i915/bdb: Fix version check
With patch "drm/i915/vbt: Fix backlight parsing for VBT 234+"
the size of bdb_lfp_backlight_data structure has been increased,
causing if-statement in the parse_lfp_backlight function
that comapres this structure size to the one retrieved from BDB,
always to fail for older revisions.
This patch calculates expected size of the structure for a given
BDB version and compares it with the value gathered from BDB.
Tested on Chromebook Pixelbook (Nocturne) (reports bdb->version = 221)
Fixes: d381baad29b4 ("drm/i915/vbt: Fix backlight parsing for VBT 234+")
Tested-by: Lukasz Majczak <lma@semihalf.com>
Signed-off-by: Lukasz Majczak <lma@semihalf.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210930134606.227234-1-lma@semihalf.com
(cherry picked from commit 4378daf5d04eed59724e6d0e74755e17dce2e105)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Diffstat (limited to 'drivers/gpu')
-rw-r--r-- | drivers/gpu/drm/i915/display/intel_bios.c | 22 | ||||
-rw-r--r-- | drivers/gpu/drm/i915/display/intel_vbt_defs.h | 5 |
2 files changed, 21 insertions, 6 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c index e86e6ed2d3bf..fd71346aac7b 100644 --- a/drivers/gpu/drm/i915/display/intel_bios.c +++ b/drivers/gpu/drm/i915/display/intel_bios.c @@ -451,13 +451,23 @@ parse_lfp_backlight(struct drm_i915_private *i915, } i915->vbt.backlight.type = INTEL_BACKLIGHT_DISPLAY_DDI; - if (bdb->version >= 191 && - get_blocksize(backlight_data) >= sizeof(*backlight_data)) { - const struct lfp_backlight_control_method *method; + if (bdb->version >= 191) { + size_t exp_size; - method = &backlight_data->backlight_control[panel_type]; - i915->vbt.backlight.type = method->type; - i915->vbt.backlight.controller = method->controller; + if (bdb->version >= 236) + exp_size = sizeof(struct bdb_lfp_backlight_data); + else if (bdb->version >= 234) + exp_size = EXP_BDB_LFP_BL_DATA_SIZE_REV_234; + else + exp_size = EXP_BDB_LFP_BL_DATA_SIZE_REV_191; + + if (get_blocksize(backlight_data) >= exp_size) { + const struct lfp_backlight_control_method *method; + + method = &backlight_data->backlight_control[panel_type]; + i915->vbt.backlight.type = method->type; + i915->vbt.backlight.controller = method->controller; + } } i915->vbt.backlight.pwm_freq_hz = entry->pwm_freq_hz; diff --git a/drivers/gpu/drm/i915/display/intel_vbt_defs.h b/drivers/gpu/drm/i915/display/intel_vbt_defs.h index 330077c2e588..a2108a8f544d 100644 --- a/drivers/gpu/drm/i915/display/intel_vbt_defs.h +++ b/drivers/gpu/drm/i915/display/intel_vbt_defs.h @@ -814,6 +814,11 @@ struct lfp_brightness_level { u16 reserved; } __packed; +#define EXP_BDB_LFP_BL_DATA_SIZE_REV_191 \ + offsetof(struct bdb_lfp_backlight_data, brightness_level) +#define EXP_BDB_LFP_BL_DATA_SIZE_REV_234 \ + offsetof(struct bdb_lfp_backlight_data, brightness_precision_bits) + struct bdb_lfp_backlight_data { u8 entry_size; struct lfp_backlight_data_entry data[16]; |