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 <nandor....@vaisala.com>
---
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;
--
2.17.2
