android/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

regmap: spi-avmm: Fix regmap_bus max_raw_write

Browse Source 
[ Upstream commit c8e796895e2310b6130e7577248da1d771431a77 ]

The max_raw_write member of the regmap_spi_avmm_bus structure is defined
as:
	.max_raw_write = SPI_AVMM_VAL_SIZE * MAX_WRITE_CNT

SPI_AVMM_VAL_SIZE == 4 and MAX_WRITE_CNT == 1 so this results in a
maximum write transfer size of 4 bytes which provides only enough space to
transfer the address of the target register. It provides no space for the
value to be transferred. This bug became an issue (divide-by-zero in
_regmap_raw_write()) after the following was accepted into mainline:

commit 3981514180c9 ("regmap: Account for register length when chunking")

Change max_raw_write to include space (4 additional bytes) for both the
register address and value:

	.max_raw_write = SPI_AVMM_REG_SIZE + SPI_AVMM_VAL_SIZE * MAX_WRITE_CNT

Fixes: 7f9fb67358 ("regmap: add Intel SPI Slave to AVMM Bus Bridge support")
Reviewed-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Link: https://lore.kernel.org/r/20230620202824.380313-1-russell.h.weight@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Russ Weight 2023-06-20 13:28:24 -07:00 committed by Greg Kroah-Hartman
parent bc35f93e4b
commit f00cd687c2
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/base/regmap/regmap-spi-avmm.c
View File

@ -666,7 +666,7 @@ static const struct regmap_bus regmap_spi_avmm_bus = {
.reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
.val_format_endian_default = REGMAP_ENDIAN_NATIVE,
.max_raw_read = SPI_AVMM_VAL_SIZE * MAX_READ_CNT,
.max_raw_write = SPI_AVMM_VAL_SIZE * MAX_WRITE_CNT,
.max_raw_write = SPI_AVMM_REG_SIZE + SPI_AVMM_VAL_SIZE * MAX_WRITE_CNT,
.free_context = spi_avmm_bridge_ctx_free,
};