i2c_smbus_write_word_data() expects a plain u16, but cpu_to_le16()
returns __le16 (a sparse-restricted endian type), causing:

  drivers/base/regmap/regmap-i2c.c:340: sparse: incorrect type in
  argument 3 (different base types)
    expected unsigned short [usertype] value
    got restricted __le16 [usertype]

SMBus already defines byte ordering internally, so cpu_to_le16() is
wrong here. Replace it with a plain (u16) cast.

Fixes: bad4bd28abf4 ("regmap-i2c: add SMBus byte/word reg16 bus for adapters lacking I2C_FUNC_I2C")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202605161621.mY5zFh4D-lkp@intel.com/
Signed-off-by: Nishanth Sampath Kumar <nissampa@cisco.com>
---
 drivers/base/regmap/regmap-i2c.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/base/regmap/regmap-i2c.c b/drivers/base/regmap/regmap-i2c.c
index 31e30dfced19..51a04961faf7 100644
--- a/drivers/base/regmap/regmap-i2c.c
+++ b/drivers/base/regmap/regmap-i2c.c
@@ -337,7 +337,7 @@ static int regmap_smbus_word_write_reg16(void *context, const void *data,
 	val = ((u8 *)data)[2];
 
 	return i2c_smbus_write_word_data(i2c, addr_hi,
-					 cpu_to_le16(((u16)val << 8) | addr_lo));
+					 ((u16)val << 8) | addr_lo);
 }
 
 static const struct regmap_bus regmap_smbus_byte_word_reg16 = {
-- 
2.25.1

On Wed, 20 May 2026 08:11:09 -0700, Nishanth Sampath Kumar wrote:
> i2c_smbus_write_word_data() expects a plain u16, but cpu_to_le16()
> returns __le16 (a sparse-restricted endian type), causing:
> 
>   drivers/base/regmap/regmap-i2c.c:340: sparse: incorrect type in
>   argument 3 (different base types)
>     expected unsigned short [usertype] value
>     got restricted __le16 [usertype]
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap.git for-next

Thanks!

[1/1] regmap-i2c: fix sparse warning in regmap_smbus_word_write_reg16
      https://git.kernel.org/broonie/misc/c/34808ac8ddaf

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
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Thanks,
Mark