[PATCH v3 2/3] staging: iio: ad9832: Refactor powerdown control

[Gabriel Shahrouzi <gshahrouzi@gmail.com>]

Replace custom implementation with out_altvoltage_powerdown ABI. The
attribute's logic is inverted (1 now enables powerdown) to match the
standard. Modernize driver by using the standard IIO interface.

Signed-off-by: Gabriel Shahrouzi <gshahrouzi@gmail.com>
---
 drivers/staging/iio/frequency/ad9832.c | 44 ++++++++++++++++++--------
 1 file changed, 30 insertions(+), 14 deletions(-)

diff --git a/drivers/staging/iio/frequency/ad9832.c b/drivers/staging/iio/frequency/ad9832.c
index 0872ff4ec4896..a8fc20379efed 100644
--- a/drivers/staging/iio/frequency/ad9832.c
+++ b/drivers/staging/iio/frequency/ad9832.c
@@ -167,6 +167,34 @@ static int ad9832_write_phase(struct ad9832_state *st,
 	return spi_sync(st->spi, &st->phase_msg);
 }
 
+static ssize_t ad9832_write_powerdown(struct device *dev, struct device_attribute *attr,
+				      const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct ad9832_state *st = iio_priv(indio_dev);
+	int ret;
+	unsigned long val;
+
+	ret = kstrtoul(buf, 10, &val);
+	if (ret)
+		goto error_ret;
+
+	mutex_lock(&st->lock);
+	if (val)
+		st->ctrl_src |= AD9832_SLEEP;
+	else
+		st->ctrl_src &= ~(AD9832_RESET | AD9832_SLEEP |
+				 AD9832_CLR);
+
+	st->data = cpu_to_be16((AD9832_CMD_SLEEPRESCLR << CMD_SHIFT) |
+				st->ctrl_src);
+	ret = spi_sync(st->spi, &st->msg);
+	mutex_unlock(&st->lock);
+
+error_ret:
+	return ret ? ret : len;
+}
+
 static ssize_t ad9832_write(struct device *dev, struct device_attribute *attr,
 			    const char *buf, size_t len)
 {
@@ -227,17 +255,6 @@ static ssize_t ad9832_write(struct device *dev, struct device_attribute *attr,
 					st->ctrl_fp);
 		ret = spi_sync(st->spi, &st->msg);
 		break;
-	case AD9832_OUTPUT_EN:
-		if (val)
-			st->ctrl_src &= ~(AD9832_RESET | AD9832_SLEEP |
-					AD9832_CLR);
-		else
-			st->ctrl_src |= AD9832_SLEEP;
-
-		st->data = cpu_to_be16((AD9832_CMD_SLEEPRESCLR << CMD_SHIFT) |
-					st->ctrl_src);
-		ret = spi_sync(st->spi, &st->msg);
-		break;
 	default:
 		ret = -ENODEV;
 	}
@@ -266,8 +283,7 @@ static IIO_CONST_ATTR_PHASE_SCALE(0, "0.0015339808"); /* 2PI/2^12 rad*/
 
 static IIO_DEV_ATTR_PINCONTROL_EN(0, 0200, NULL,
 				ad9832_write, AD9832_PINCTRL_EN);
-static IIO_DEV_ATTR_OUT_ENABLE(0, 0200, NULL,
-				ad9832_write, AD9832_OUTPUT_EN);
+static IIO_DEVICE_ATTR(out_altvoltage_powerdown, 0200, NULL, ad9832_write_powerdown, 0);
 
 static struct attribute *ad9832_attributes[] = {
 	&iio_dev_attr_out_altvoltage0_frequency0.dev_attr.attr,
@@ -281,7 +297,7 @@ static struct attribute *ad9832_attributes[] = {
 	&iio_dev_attr_out_altvoltage0_pincontrol_en.dev_attr.attr,
 	&iio_dev_attr_out_altvoltage0_frequencysymbol.dev_attr.attr,
 	&iio_dev_attr_out_altvoltage0_phasesymbol.dev_attr.attr,
-	&iio_dev_attr_out_altvoltage0_out_enable.dev_attr.attr,
+	&iio_dev_attr_out_altvoltage_powerdown.dev_attr.attr,
 	NULL,
 };
 
-- 
2.43.0