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This is problematic because: 1. A successful I2C transfer returns the number of bytes sent (2), but the caller might expect 0 for success. 2. If a partial transfer occurs (e.g., only 1 byte sent), it would be treated as success by the caller checking for negative values. This patch refactors the return value handling to: - Propagate negative error codes from the I2C core. - Return -EIO in case of incomplete transfers (short writes). - Return 0 on complete success. Fixes: 472988972737 ("iio: add support of the max5821") Signed-off-by: Salah Triki --- drivers/iio/dac/max5821.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/iio/dac/max5821.c b/drivers/iio/dac/max5821.c index e7e29359f8fe..bd14f578d8c5 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_data *data, const struct iio_chan_spec *chan) { u8 outbuf[2]; + int ret; outbuf[0] = MAX5821_EXTENDED_COMMAND_MODE; @@ -103,7 +104,15 @@ static int max5821_sync_powerdown_mode(struct max5821_data *data, else outbuf[1] |= MAX5821_EXTENDED_POWER_UP; - return i2c_master_send(data->client, outbuf, 2); + ret = i2c_master_send(data->client, outbuf, 2); + + if (ret < 0) + return ret; + + if (ret != 2) + return -EIO; + + return 0; } static ssize_t max5821_write_dac_powerdown(struct iio_dev *indio_dev, -- 2.43.0