iio: dac: stm32-dac: better handle reset controller failures

Use devm_reset_control_get_optional_exclusive() instead of
devm_reset_control_get_exclusive() as reset controller is optional.

Nevertheless if reset controller is expected but reports an
error, propagate the error code to the caller. In such case
a nice error trace is emitted unless we're deferring the probe
operation.

Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Etienne Carriere 2020-01-13 14:14:26 +01:00 committed by Jonathan Cameron
parent 4a001c96b1
commit d344961f55

View file

@ -147,8 +147,16 @@ static int stm32_dac_probe(struct platform_device *pdev)
priv->common.vref_mv = ret / 1000;
dev_dbg(dev, "vref+=%dmV\n", priv->common.vref_mv);
rst = devm_reset_control_get_exclusive(dev, NULL);
if (!IS_ERR(rst)) {
rst = devm_reset_control_get_optional_exclusive(dev, NULL);
if (rst) {
if (IS_ERR(rst)) {
ret = PTR_ERR(rst);
if (ret != -EPROBE_DEFER)
dev_err(dev, "reset get failed, %d\n", ret);
goto err_hw_stop;
}
reset_control_assert(rst);
udelay(2);
reset_control_deassert(rst);