On Mon, 10 May 2021 15:55:19 +0300
Alexandru Ardelean <aardelean@xxxxxxxxxxx> wrote:
> With the devm_ad_sd_setup_buffer_and_trigger() helper, it's a bit easier
> now to convert the probe of the AD7192 driver to use device-managed
> functions.
>
> The regulators and the mclk requires devm_add_action_or_reset() callbacks
> though.
>
> Signed-off-by: Alexandru Ardelean <aardelean@xxxxxxxxxxx>
I'm fairly sure there's another bug in here... See below.
> ---
> drivers/iio/adc/ad7192.c | 90 ++++++++++++++++------------------------
> 1 file changed, 36 insertions(+), 54 deletions(-)
>
> diff --git a/drivers/iio/adc/ad7192.c b/drivers/iio/adc/ad7192.c
> index 5b3c46213bd4..b3fa1b5764e9 100644
> --- a/drivers/iio/adc/ad7192.c
> +++ b/drivers/iio/adc/ad7192.c
> @@ -908,6 +908,16 @@ static int ad7192_channels_config(struct iio_dev *indio_dev)
> return 0;
> }
>
> +static void ad7192_reg_disable(void *reg)
> +{
> + regulator_disable(reg);
> +}
> +
> +static void ad7192_clk_disable(void *clk)
> +{
> + clk_disable_unprepare(clk);
> +}
> +
> static int ad7192_probe(struct spi_device *spi)
> {
> struct ad7192_state *st;
> @@ -937,36 +947,40 @@ static int ad7192_probe(struct spi_device *spi)
> return ret;
> }
>
> + ret = devm_add_action_or_reset(&spi->dev, ad7192_reg_disable, st->avdd);
> + if (ret)
> + return ret;
> +
> st->dvdd = devm_regulator_get(&spi->dev, "dvdd");
> - if (IS_ERR(st->dvdd)) {
> - ret = PTR_ERR(st->dvdd);
> - goto error_disable_avdd;
> - }
> + if (IS_ERR(st->dvdd))
> + return PTR_ERR(st->dvdd);
>
> ret = regulator_enable(st->dvdd);
> if (ret) {
> dev_err(&spi->dev, "Failed to enable specified DVdd supply\n");
> - goto error_disable_avdd;
> + return ret;
> }
>
> + ret = devm_add_action_or_reset(&spi->dev, ad7192_reg_disable, st->dvdd);
> + if (ret)
> + return ret;
> +
> voltage_uv = regulator_get_voltage(st->avdd);
>
> if (voltage_uv > 0) {
> st->int_vref_mv = voltage_uv / 1000;
> } else {
> - ret = voltage_uv;
> dev_err(&spi->dev, "Device tree error, reference voltage undefined\n");
> - goto error_disable_avdd;
> + return voltage_uv;
There is a corner case here (in original code and new code).
What if voltage_uv == 0? Driver reports successful probe. Not what we
want to happen.
> }
>
> - spi_set_drvdata(spi, indio_dev);
> st->chip_info = of_device_get_match_data(&spi->dev);
> indio_dev->name = st->chip_info->name;
> indio_dev->modes = INDIO_DIRECT_MODE;
>
> ret = ad7192_channels_config(indio_dev);
> if (ret < 0)
> - goto error_disable_dvdd;
> + return ret;
>
> if (st->chip_info->chip_id == CHIPID_AD7195)
> indio_dev->info = &ad7195_info;
> @@ -975,17 +989,15 @@ static int ad7192_probe(struct spi_device *spi)
>
> ad_sd_init(&st->sd, indio_dev, spi, &ad7192_sigma_delta_info);
>
> - ret = ad_sd_setup_buffer_and_trigger(indio_dev);
> + ret = devm_ad_sd_setup_buffer_and_trigger(&spi->dev, indio_dev);
> if (ret)
> - goto error_disable_dvdd;
> + return ret;
>
> st->fclk = AD7192_INT_FREQ_MHZ;
>
> st->mclk = devm_clk_get_optional(&spi->dev, "mclk");
> - if (IS_ERR(st->mclk)) {
> - ret = PTR_ERR(st->mclk);
> - goto error_remove_trigger;
> - }
> + if (IS_ERR(st->mclk))
> + return PTR_ERR(st->mclk);
>
> st->clock_sel = ad7192_of_clock_select(st);
>
> @@ -993,55 +1005,26 @@ static int ad7192_probe(struct spi_device *spi)
> st->clock_sel == AD7192_CLK_EXT_MCLK2) {
> ret = clk_prepare_enable(st->mclk);
> if (ret < 0)
> - goto error_remove_trigger;
> + return ret;
> +
> + ret = devm_add_action_or_reset(&spi->dev, ad7192_clk_disable,
> + st->mclk);
> + if (ret)
> + return ret;
>
> st->fclk = clk_get_rate(st->mclk);
> if (!ad7192_valid_external_frequency(st->fclk)) {
> - ret = -EINVAL;
> dev_err(&spi->dev,
> "External clock frequency out of bounds\n");
> - goto error_disable_clk;
> + return -EINVAL;
> }
> }
>
> ret = ad7192_setup(st, spi->dev.of_node);
> if (ret)
> - goto error_disable_clk;
> -
> - ret = iio_device_register(indio_dev);
> - if (ret < 0)
> - goto error_disable_clk;
> - return 0;
> -
> -error_disable_clk:
> - if (st->clock_sel == AD7192_CLK_EXT_MCLK1_2 ||
> - st->clock_sel == AD7192_CLK_EXT_MCLK2)
> - clk_disable_unprepare(st->mclk);
> -error_remove_trigger:
> - ad_sd_cleanup_buffer_and_trigger(indio_dev);
> -error_disable_dvdd:
> - regulator_disable(st->dvdd);
> -error_disable_avdd:
> - regulator_disable(st->avdd);
> -
> - return ret;
> -}
> -
> -static int ad7192_remove(struct spi_device *spi)
> -{
> - struct iio_dev *indio_dev = spi_get_drvdata(spi);
> - struct ad7192_state *st = iio_priv(indio_dev);
> -
> - iio_device_unregister(indio_dev);
> - if (st->clock_sel == AD7192_CLK_EXT_MCLK1_2 ||
> - st->clock_sel == AD7192_CLK_EXT_MCLK2)
> - clk_disable_unprepare(st->mclk);
> - ad_sd_cleanup_buffer_and_trigger(indio_dev);
> -
> - regulator_disable(st->dvdd);
> - regulator_disable(st->avdd);
> + return ret;
>
> - return 0;
> + return devm_iio_device_register(&spi->dev, indio_dev);
> }
>
> static const struct of_device_id ad7192_of_match[] = {
> @@ -1059,7 +1042,6 @@ static struct spi_driver ad7192_driver = {
> .of_match_table = ad7192_of_match,
> },
> .probe = ad7192_probe,
> - .remove = ad7192_remove,
> };
> module_spi_driver(ad7192_driver);
>
