On Mon, 4 Jul 2022 19:21:11 +0200
Marcus Folkesson <marcus.folkesson@xxxxxxxxx> wrote:
> Keep using managed resources as much as possible.
>
> Signed-off-by: Marcus Folkesson <marcus.folkesson@xxxxxxxxx>
> ---
> drivers/iio/adc/mcp3911.c | 43 ++++++++++++++++-----------------------
> 1 file changed, 18 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/iio/adc/mcp3911.c b/drivers/iio/adc/mcp3911.c
> index 890af7dca62d..f5fd9da6ab55 100644
> --- a/drivers/iio/adc/mcp3911.c
> +++ b/drivers/iio/adc/mcp3911.c
> @@ -258,6 +258,16 @@ static int mcp3911_config(struct mcp3911 *adc)
> return mcp3911_write(adc, MCP3911_REG_CONFIG, configreg, 2);
> }
>
> +static void mcp3911_cleanup(void *_adc)
Very rarely a good idea to cleanup more than one thing in a given
devm_ callback.
> +{
> + struct mcp3911 *adc = _adc;
> +
> + if (adc->clki)
> + clk_disable_unprepare(adc->clki);
> + if (adc->vref)
> + regulator_disable(adc->vref);
> +}
> +
> static int mcp3911_probe(struct spi_device *spi)
> {
> struct iio_dev *indio_dev;
> @@ -271,6 +281,10 @@ static int mcp3911_probe(struct spi_device *spi)
> adc = iio_priv(indio_dev);
> adc->spi = spi;
>
> + ret = devm_add_action_or_reset(&spi->dev, mcp3911_cleanup, adc);
> + if (ret)
> + return ret;
You should only register this 'after' what it cleans up. I want to see
a clear pairing between setup and tear down.
In this particular case register two callbacks, and only register them
if they have anything to do. i.e. the ->clki and ->vref are not null
respectively.
Jonathan
> +
> adc->vref = devm_regulator_get_optional(&adc->spi->dev, "vref");
> if (IS_ERR(adc->vref)) {
> if (PTR_ERR(adc->vref) == -ENODEV) {
> @@ -296,21 +310,20 @@ static int mcp3911_probe(struct spi_device *spi)
> dev_err(&adc->spi->dev,
> "failed to get adc clk (%ld)\n",
> PTR_ERR(adc->clki));
> - ret = PTR_ERR(adc->clki);
> - goto reg_disable;
> + return PTR_ERR(adc->clki);
> }
> } else {
> ret = clk_prepare_enable(adc->clki);
> if (ret < 0) {
> dev_err(&adc->spi->dev,
> "Failed to enable clki: %d\n", ret);
> - goto reg_disable;
> + return ret;
> }
> }
>
> ret = mcp3911_config(adc);
> if (ret)
> - goto clk_disable;
> + return ret;
>
> indio_dev->name = spi_get_device_id(spi)->name;
> indio_dev->modes = INDIO_DIRECT_MODE;
> @@ -322,31 +335,11 @@ static int mcp3911_probe(struct spi_device *spi)
>
> mutex_init(&adc->lock);
>
> - ret = iio_device_register(indio_dev);
> - if (ret)
> - goto clk_disable;
> -
> - return ret;
> -
> -clk_disable:
> - clk_disable_unprepare(adc->clki);
> -reg_disable:
> - if (adc->vref)
> - regulator_disable(adc->vref);
> -
> - return ret;
> + return devm_iio_device_register(&adc->spi->dev, indio_dev);
> }
>
> static void mcp3911_remove(struct spi_device *spi)
> {
> - struct iio_dev *indio_dev = spi_get_drvdata(spi);
> - struct mcp3911 *adc = iio_priv(indio_dev);
> -
> - iio_device_unregister(indio_dev);
> -
> - clk_disable_unprepare(adc->clki);
> - if (adc->vref)
> - regulator_disable(adc->vref);
> }
>
> static const struct of_device_id mcp3911_dt_ids[] = {
