The patch regmap: verify if register is writeable before writing operations
has been applied to the regmap tree at https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap.git All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark >From 8b9f9d4dc511309918c4f6793bae7387c0c638af Mon Sep 17 00:00:00 2001 From: Han Nandor <[email protected]> Date: Tue, 2 Apr 2019 08:01:22 +0000 Subject: [PATCH] regmap: verify if register is writeable before writing operations regmap provides a couple of ways to validate the register range used. a) maxim allowed register, b) writable/readable register tables, c) callback function that can be provided by the driver to validate a register. regmap framework should verify if registers are writeable before every write operation. However this doesn't seems to happen in every situation. The method `_regmap_raw_write_impl` is only using the `writeable_reg` callback to verify if register is writeable, ignoring the other two. This can lead to undefined behaviour since this allows to write to registers that could be declared un-writeable by using any other option. Change `_regmap_raw_write_impl` to use the `regmap_writeable` method to verify if registers are writable before the write operation. Signed-off-by: Nandor Han <[email protected]> Signed-off-by: Mark Brown <[email protected]> --- drivers/base/regmap/regmap.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 4f822e087def..42d8404bc8cc 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -1493,11 +1493,10 @@ static int _regmap_raw_write_impl(struct regmap *map, unsigned int reg, WARN_ON(!map->bus); /* Check for unwritable registers before we start */ - if (map->writeable_reg) - for (i = 0; i < val_len / map->format.val_bytes; i++) - if (!map->writeable_reg(map->dev, - reg + regmap_get_offset(map, i))) - return -EINVAL; + for (i = 0; i < val_len / map->format.val_bytes; i++) + if (!regmap_writeable(map, + reg + regmap_get_offset(map, i))) + return -EINVAL; if (!map->cache_bypass && map->format.parse_val) { unsigned int ival; -- 2.20.1

