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If a partial transfer occurred, it would be incorrectly treated as a success by the caller. While the caller currently handles the positive return value of 2 as success, this patch refactors the function to return 0 on full success and -EIO on short writes. This ensures robust error handling for incomplete transfers and improves code maintainability by using sizeof(outbuf). Fixes: 472988972737 ("iio: add support of the max5821") Signed-off-by: Salah Triki --- Changes in v2: - Replace magic number '2' with 'sizeof(outbuf)' for better maintainability. - Remove redundant blank line between i2c_master_send() and error check. - Update commit message to clarify that the 'Fixes' tag is primarily for=20 handling partial transfers (short writes), as the caller already=20 handled the success case correctly. drivers/iio/dac/max5821.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/iio/dac/max5821.c b/drivers/iio/dac/max5821.c index e7e29359f8fe..f3b45e1429a4 100644 --- a/drivers/iio/dac/max5821.c +++ b/drivers/iio/dac/max5821.c @@ -90,6 +90,7 @@ static int max5821_sync_powerdown_mode(struct max5821_dat= a *data, const struct iio_chan_spec *chan) { u8 outbuf[2]; + int ret; =20 outbuf[0] =3D MAX5821_EXTENDED_COMMAND_MODE; =20 @@ -103,7 +104,14 @@ static int max5821_sync_powerdown_mode(struct max5821_= data *data, else outbuf[1] |=3D MAX5821_EXTENDED_POWER_UP; =20 - return i2c_master_send(data->client, outbuf, 2); + ret =3D i2c_master_send(data->client, outbuf, sizeof(outbuf)); + + if (ret < 0) + return ret; + if (ret !=3D sizeof(outbuf)) + return -EIO; + + return 0; } =20 static ssize_t max5821_write_dac_powerdown(struct iio_dev *indio_dev, --=20 2.43.0