Merge tag 'iio-fixes-for-4.7c' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus

Jonathan writes:

Third set of fixes for IIO in the 4.7 cycle.

A couple of really old bugs and the results of Mark taking a close look at
some nasty regulator handling.

* ad7266
  - Fix broken regulator handling that won't play well with dummy regulators.
  - Correctly handle and optional regulator.
  - Fix probe deferral for the vref regulator.
* kxsd9
  - Fix a wrong error check that leads to an inability to write or read
  the scale.
* sca3000
  - Fix a wrong error check that leads to an inability to read back the
  sampling frequency.

3 files changed, 8 insertions, 5 deletions

diff --git a/drivers/iio/accel/kxsd9.c b/drivers/iio/accel/kxsd9.c
index 923f56598d4b..3a9f106787d2 100644
--- a/drivers/iio/accel/kxsd9.c
+++ b/drivers/iio/accel/kxsd9.c
@@ -81,7 +81,7 @@ static int kxsd9_write_scale(struct iio_dev *indio_dev, int micro)
 
         mutex_lock(&st->buf_lock);
         ret = spi_w8r8(st->us, KXSD9_READ(KXSD9_REG_CTRL_C));
-        if (ret)
+        if (ret < 0)
                 goto error_ret;
         st->tx[0] = KXSD9_WRITE(KXSD9_REG_CTRL_C);
         st->tx[1] = (ret & ~KXSD9_FS_MASK) | i;
@@ -163,7 +163,7 @@ static int kxsd9_read_raw(struct iio_dev *indio_dev,
                 break;
         case IIO_CHAN_INFO_SCALE:
                 ret = spi_w8r8(st->us, KXSD9_READ(KXSD9_REG_CTRL_C));
-                if (ret)
+                if (ret < 0)
                         goto error_ret;
                 *val2 = kxsd9_micro_scales[ret & KXSD9_FS_MASK];
                 ret = IIO_VAL_INT_PLUS_MICRO;
diff --git a/drivers/iio/adc/ad7266.c b/drivers/iio/adc/ad7266.c
index 21e19b60e2b9..2123f0ac2e2a 100644
--- a/drivers/iio/adc/ad7266.c
+++ b/drivers/iio/adc/ad7266.c
@@ -396,8 +396,8 @@ static int ad7266_probe(struct spi_device *spi)
 
         st = iio_priv(indio_dev);
 
-        st->reg = devm_regulator_get(&spi->dev, "vref");
-        if (!IS_ERR_OR_NULL(st->reg)) {
+        st->reg = devm_regulator_get_optional(&spi->dev, "vref");
+        if (!IS_ERR(st->reg)) {
                 ret = regulator_enable(st->reg);
                 if (ret)
                         return ret;
@@ -408,6 +408,9 @@ static int ad7266_probe(struct spi_device *spi)
 
                 st->vref_mv = ret / 1000;
         } else {
+                /* Any other error indicates that the regulator does exist */
+                if (PTR_ERR(st->reg) != -ENODEV)
+                        return PTR_ERR(st->reg);
                 /* Use internal reference */
                 st->vref_mv = 2500;
         }
diff --git a/drivers/staging/iio/accel/sca3000_core.c b/drivers/staging/iio/accel/sca3000_core.c
index a8f533af9eca..ec12181822e6 100644
--- a/drivers/staging/iio/accel/sca3000_core.c
+++ b/drivers/staging/iio/accel/sca3000_core.c
@@ -594,7 +594,7 @@ static ssize_t sca3000_read_frequency(struct device *dev,
                 goto error_ret_mut;
         ret = sca3000_read_ctrl_reg(st, SCA3000_REG_CTRL_SEL_OUT_CTRL);
         mutex_unlock(&st->lock);
-        if (ret)
+        if (ret < 0)
                 goto error_ret;
         val = ret;
         if (base_freq > 0)