hwmon: (sht3x) Return the consumed count for heater writes

heater_enable_store() returns the result of i2c_master_send(), which is
the two-byte command length on success rather than the sysfs input
count. This can report more bytes than were supplied, or a partial write
for a fully processed input. For example, writing "on\n" returns two
instead of three, so a caller retrying the remaining newline gets
-EINVAL even though the heater command succeeded. Retrying the remainder
of "off\n" can also send the heater-off command twice.

Return count after a complete command transfer. Preserve negative I2C
errors and return -EIO for nonnegative incomplete transfers, so a
zero-message transfer is not reported as a successful zero-byte write.
Keep the existing boolean parsing, command selection and locking.

Fixes: 50c22cd154e5 ("hwmon: (sht3x) add humidity heater element control")
Cc: stable@vger.kernel.org
Signed-off-by: Baek Kyu, Kim <pocj8ur4in@gmail.com>
Link: https://patch.msgid.link/20261019154718.2328055-1-pocj8ur4in@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

0 files changed, 0 insertions, 0 deletions