Re: [PATCH 1/2] staging: iio: cdc: ad7746: clean up driver comments and probe return

From: Jonathan Cameron
Date: Thu May 13 2021 - 11:59:13 EST


On Tue, 11 May 2021 17:54:01 -0300
Lucas Stankus <lucas.p.stankus@xxxxxxxxx> wrote:

> Remove vague comments, align temperature comment with indent block and
> simplify probe return on device register.
>
> Also fix the following checkpatch warning:
> CHECK: Alignment should match open parenthesis
>
> Signed-off-by: Lucas Stankus <lucas.p.stankus@xxxxxxxxx>

As Fabio pointed out, finer grained patches with one type of change per
patch would be good.

> ---
> drivers/staging/iio/cdc/ad7746.c | 31 ++++++++++---------------------
> 1 file changed, 10 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/staging/iio/cdc/ad7746.c b/drivers/staging/iio/cdc/ad7746.c
> index dfd71e99e872..e03d010b2f4c 100644
> --- a/drivers/staging/iio/cdc/ad7746.c
> +++ b/drivers/staging/iio/cdc/ad7746.c
> @@ -84,10 +84,6 @@
> #define AD7746_CAPDAC_DACEN BIT(7)
> #define AD7746_CAPDAC_DACP(x) ((x) & 0x7F)
>
> -/*
> - * struct ad7746_chip_info - chip specific information
> - */
> -
> struct ad7746_chip_info {
> struct i2c_client *client;
> struct mutex lock; /* protect sensor state */
> @@ -232,13 +228,14 @@ static int ad7746_select_channel(struct iio_dev *indio_dev,
>
> if (chip->capdac_set != chan->channel) {
> ret = i2c_smbus_write_byte_data(chip->client,
> - AD7746_REG_CAPDACA,
> - chip->capdac[chan->channel][0]);
> + AD7746_REG_CAPDACA,
> + chip->capdac[chan->channel][0]);
> if (ret < 0)
> return ret;
> +
> ret = i2c_smbus_write_byte_data(chip->client,
> - AD7746_REG_CAPDACB,
> - chip->capdac[chan->channel][1]);
> + AD7746_REG_CAPDACB,
> + chip->capdac[chan->channel][1]);
> if (ret < 0)
> return ret;

I wondered if it might be sensible to factor this code out to reduce the indent
and make things more readable. Having taken a look it seems there is another
place with exactly the same call sequence. From how it's used there, I'm
assuming this is updating the offsets. As such, I would introduce an

ad7746_offsets_set(struct iio_dev *indio_dev, int channel)

or similar.


>
> @@ -564,10 +561,10 @@ static int ad7746_read_raw(struct iio_dev *indio_dev,
>
> switch (chan->type) {
> case IIO_TEMP:
> - /*
> - * temperature in milli degrees Celsius
> - * T = ((*val / 2048) - 4096) * 1000
> - */
> + /*
> + * temperature in milli degrees Celsius
> + * T = ((*val / 2048) - 4096) * 1000
> + */
> *val = (*val * 125) / 256;
> break;
> case IIO_VOLTAGE:
> @@ -669,10 +666,6 @@ static const struct iio_info ad7746_info = {
> .write_raw = ad7746_write_raw,
> };
>
> -/*
> - * device probe and remove
> - */
> -
> static int ad7746_probe(struct i2c_client *client,
> const struct i2c_device_id *id)
> {
> @@ -730,11 +723,7 @@ static int ad7746_probe(struct i2c_client *client,
> if (ret < 0)
> return ret;
>
> - ret = devm_iio_device_register(indio_dev->dev.parent, indio_dev);
> - if (ret)
> - return ret;
> -
> - return 0;
> + return devm_iio_device_register(indio_dev->dev.parent, indio_dev);
> }
>
> static const struct i2c_device_id ad7746_id[] = {