iio: adc: max11410: Factor out writing of sampling frequency to simplify errro paths.

Introduce __max11410_write_samp_freq() helper and use guard() to avoid
need for manual unlock of the mutex. This allows direct returns and
simplifies the resulting error handling.

Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://patch.msgid.link/20250217141630.897334-26-jic23@kernel.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/adc/max11410.c b/drivers/iio/adc/max11410.c
index 76abafd4740449f1c4a518be22a1a28e935b7667..6e06c62715a80fc58f29c3ee6e7e122952d9c49c 100644 (file)
--- a/drivers/iio/adc/max11410.c
+++ b/drivers/iio/adc/max11410.c
@@ -507,12 +507,37 @@ static int max11410_read_raw(struct iio_dev *indio_dev,
        return -EINVAL;
 }
 
+static int __max11410_write_samp_freq(struct max11410_state *st,
+                                     int val, int val2)
+{
+       int ret, i, reg_val, filter;
+
+       guard(mutex)(&st->lock);
+
+       ret = regmap_read(st->regmap, MAX11410_REG_FILTER, &reg_val);
+       if (ret)
+               return ret;
+
+       filter = FIELD_GET(MAX11410_FILTER_LINEF_MASK, reg_val);
+
+       for (i = 0; i < max11410_sampling_len[filter]; ++i) {
+               if (val == max11410_sampling_rates[filter][i][0] &&
+                   val2 == max11410_sampling_rates[filter][i][1])
+                       break;
+       }
+       if (i == max11410_sampling_len[filter])
+               return -EINVAL;
+
+       return regmap_write_bits(st->regmap, MAX11410_REG_FILTER,
+                                MAX11410_FILTER_RATE_MASK, i);
+}
+
 static int max11410_write_raw(struct iio_dev *indio_dev,
                              struct iio_chan_spec const *chan,
                              int val, int val2, long mask)
 {
        struct max11410_state *st = iio_priv(indio_dev);
-       int i, ret, reg_val, filter, gain;
+       int ret, gain;
        u32 *scale_avail;
 
        switch (mask) {
@@ -544,29 +569,7 @@ static int max11410_write_raw(struct iio_dev *indio_dev,
                if (ret)
                        return ret;
 
-               mutex_lock(&st->lock);
-
-               ret = regmap_read(st->regmap, MAX11410_REG_FILTER, &reg_val);
-               if (ret)
-                       goto out;
-
-               filter = FIELD_GET(MAX11410_FILTER_LINEF_MASK, reg_val);
-
-               for (i = 0; i < max11410_sampling_len[filter]; ++i) {
-                       if (val == max11410_sampling_rates[filter][i][0] &&
-                           val2 == max11410_sampling_rates[filter][i][1])
-                               break;
-               }
-               if (i == max11410_sampling_len[filter]) {
-                       ret = -EINVAL;
-                       goto out;
-               }
-
-               ret = regmap_write_bits(st->regmap, MAX11410_REG_FILTER,
-                                       MAX11410_FILTER_RATE_MASK, i);
-
-out:
-               mutex_unlock(&st->lock);
+               ret = __max11410_write_samp_freq(st, val, val2);
                iio_device_release_direct_mode(indio_dev);
 
                return ret;