Re: [PATCH 02/10] iio: imu: adis16400: check ret val for non-zero vs less-than-zero

From: Jonathan Cameron
Date: Sun Nov 03 2019 - 05:22:03 EST


On Fri, 1 Nov 2019 11:34:57 +0200
Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> wrote:

> The ADIS library functions return zero on success, and negative values for
> error. Positive values aren't returned, but we only care about the success
> value (which is zero).
>
> This change is mostly needed so that the compiler won't make any inferences
> about some about values being potentially un-initialized. This only
> triggers after making some functions inline, because the compiler can
> better follow return paths.
>
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
Applied,

An observation whilst I was looking at the driver though...

It has some cases of goto label; where the label doesn't then do anything
in *_initial_setup. Direct returns would be a bit neater.

Really minor point but if you happen to be touching that driver again
soon nice to tidy up ;)

Thanks,

Jonathan


> ---
> drivers/iio/imu/adis16400.c | 22 +++++++++++-----------
> 1 file changed, 11 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/iio/imu/adis16400.c b/drivers/iio/imu/adis16400.c
> index 0575ff706bd4..44e46dc96e00 100644
> --- a/drivers/iio/imu/adis16400.c
> +++ b/drivers/iio/imu/adis16400.c
> @@ -217,16 +217,16 @@ static ssize_t adis16400_show_serial_number(struct file *file,
> int ret;
>
> ret = adis_read_reg_16(&st->adis, ADIS16334_LOT_ID1, &lot1);
> - if (ret < 0)
> + if (ret)
> return ret;
>
> ret = adis_read_reg_16(&st->adis, ADIS16334_LOT_ID2, &lot2);
> - if (ret < 0)
> + if (ret)
> return ret;
>
> ret = adis_read_reg_16(&st->adis, ADIS16334_SERIAL_NUMBER,
> &serial_number);
> - if (ret < 0)
> + if (ret)
> return ret;
>
> len = snprintf(buf, sizeof(buf), "%.4x-%.4x-%.4x\n", lot1, lot2,
> @@ -249,7 +249,7 @@ static int adis16400_show_product_id(void *arg, u64 *val)
> int ret;
>
> ret = adis_read_reg_16(&st->adis, ADIS16400_PRODUCT_ID, &prod_id);
> - if (ret < 0)
> + if (ret)
> return ret;
>
> *val = prod_id;
> @@ -266,7 +266,7 @@ static int adis16400_show_flash_count(void *arg, u64 *val)
> int ret;
>
> ret = adis_read_reg_16(&st->adis, ADIS16400_FLASH_CNT, &flash_count);
> - if (ret < 0)
> + if (ret)
> return ret;
>
> *val = flash_count;
> @@ -327,7 +327,7 @@ static int adis16334_get_freq(struct adis16400_state *st)
> uint16_t t;
>
> ret = adis_read_reg_16(&st->adis, ADIS16400_SMPL_PRD, &t);
> - if (ret < 0)
> + if (ret)
> return ret;
>
> t >>= ADIS16334_RATE_DIV_SHIFT;
> @@ -359,7 +359,7 @@ static int adis16400_get_freq(struct adis16400_state *st)
> uint16_t t;
>
> ret = adis_read_reg_16(&st->adis, ADIS16400_SMPL_PRD, &t);
> - if (ret < 0)
> + if (ret)
> return ret;
>
> sps = (t & ADIS16400_SMPL_PRD_TIME_BASE) ? 52851 : 1638404;
> @@ -416,7 +416,7 @@ static int adis16400_set_filter(struct iio_dev *indio_dev, int sps, int val)
> }
>
> ret = adis_read_reg_16(&st->adis, ADIS16400_SENS_AVG, &val16);
> - if (ret < 0)
> + if (ret)
> return ret;
>
> ret = adis_write_reg_16(&st->adis, ADIS16400_SENS_AVG,
> @@ -615,7 +615,7 @@ static int adis16400_read_raw(struct iio_dev *indio_dev,
> ret = adis_read_reg_16(&st->adis,
> ADIS16400_SENS_AVG,
> &val16);
> - if (ret < 0) {
> + if (ret) {
> mutex_unlock(&indio_dev->mlock);
> return ret;
> }
> @@ -626,12 +626,12 @@ static int adis16400_read_raw(struct iio_dev *indio_dev,
> *val2 = (ret % 1000) * 1000;
> }
> mutex_unlock(&indio_dev->mlock);
> - if (ret < 0)
> + if (ret)
> return ret;
> return IIO_VAL_INT_PLUS_MICRO;
> case IIO_CHAN_INFO_SAMP_FREQ:
> ret = st->variant->get_freq(st);
> - if (ret < 0)
> + if (ret)
> return ret;
> *val = ret / 1000;
> *val2 = (ret % 1000) * 1000;