[PATCH v6 09/12] iio: dac: ad5686: add helpers to handle powerdown masks

Rodrigo Alencar via B4 Relay
2026-05-05T12:35:10Z

Add ad5686_pd_field_set() and ad5686_pd_field_get() helpers to cleanup
powerdown mask control. Define AD5686_PD_* constants, e.g. AD5686_PD_MSK
to hold powerdown mask value for a single channel. AD5686_LDAC_PWRDN_*
macros are replaced by AD5686_PD_MODE_*, because they are unused and the
LDAC feature for async load of DAC channel values is not related to power
down control.

Signed-off-by: Rodrigo Alencar <rodrigo.alencar@analog.com>
---
drivers/iio/dac/ad5686.c | 42 ++++++++++++++++++++++++++----------------
drivers/iio/dac/ad5686.h | 13 ++++++++-----
2 files changed, 34 insertions(+), 21 deletions(-)

diff --git a/drivers/iio/dac/ad5686.c b/drivers/iio/dac/ad5686.c
index 431e7650704e..222f1696affe 100644
--- a/drivers/iio/dac/ad5686.c
+++ b/drivers/iio/dac/ad5686.c
@@ -33,28 +33,40 @@ static inline unsigned int ad5686_pd_mask_shift(const struct iio_chan_spec *chan
return __ffs(chan->address) * 2;
}

+static inline void ad5686_pd_field_set(const struct iio_chan_spec *chan,
+ unsigned int *pd, unsigned int val)
+{
+ unsigned int shift = ad5686_pd_mask_shift(chan);
+
+ *pd = (*pd & ~(AD5686_PD_MSK << shift)) | ((val & AD5686_PD_MSK) << shift);
+}
+
+static inline unsigned int ad5686_pd_field_get(const struct iio_chan_spec *chan,
+ unsigned int pd)
+{
+ unsigned int shift = ad5686_pd_mask_shift(chan);
+
+ return (pd >> shift) & AD5686_PD_MSK;
+}
+
static int ad5686_get_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
- unsigned int shift = ad5686_pd_mask_shift(chan);
struct ad5686_state *st = iio_priv(indio_dev);

guard(mutex)(&st->lock);

- return ((st->pwr_down_mode >> shift) & 0x3U) - 1;
+ return ad5686_pd_field_get(chan, st->pwr_down_mode) - 1;
}

static int ad5686_set_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
unsigned int mode)
{
- unsigned int shift = ad5686_pd_mask_shift(chan);
struct ad5686_state *st = iio_priv(indio_dev);

guard(mutex)(&st->lock);
-
- st->pwr_down_mode &= ~(0x3U << shift);
- st->pwr_down_mode |= (mode + 1) << shift;
+ ad5686_pd_field_set(chan, &st->pwr_down_mode, mode + 1);

return 0;
}
@@ -69,12 +81,12 @@ static const struct iio_enum ad5686_powerdown_mode_enum = {
static ssize_t ad5686_read_dac_powerdown(struct iio_dev *indio_dev,
uintptr_t private, const struct iio_chan_spec *chan, char *buf)
{
- unsigned int shift = ad5686_pd_mask_shift(chan);
struct ad5686_state *st = iio_priv(indio_dev);

guard(mutex)(&st->lock);

- return sysfs_emit(buf, "%d\n", !!(st->pwr_down_mask & (0x3U << shift)));
+ return sysfs_emit(buf, "%d\n",
+ !!ad5686_pd_field_get(chan, st->pwr_down_mask));
}

static ssize_t ad5686_write_dac_powerdown(struct iio_dev *indio_dev,
@@ -95,10 +107,8 @@ static ssize_t ad5686_write_dac_powerdown(struct iio_dev *indio_dev,

guard(mutex)(&st->lock);

- if (readin)
- st->pwr_down_mask |= 0x3U << ad5686_pd_mask_shift(chan);
- else
- st->pwr_down_mask &= ~(0x3U << ad5686_pd_mask_shift(chan));
+ ad5686_pd_field_set(chan, &st->pwr_down_mask,
+ readin ? AD5686_PD_MSK_PWR_DOWN : AD5686_PD_MSK_PWR_UP);

switch (st->chip_info->regmap_type) {
case AD5310_REGMAP:
@@ -471,10 +481,10 @@ int ad5686_probe(struct device *dev,

/* Set all the power down mode for all channels to 1K pulldown */
for (i = 0; i < st->chip_info->num_channels; i++) {
- shift = ad5686_pd_mask_shift(&st->chip_info->channels[i]);
- st->pwr_down_mask &= ~(0x3U << shift); /* powered up state */
- st->pwr_down_mode &= ~(0x3U << shift);
- st->pwr_down_mode |= 0x01U << shift;
+ ad5686_pd_field_set(&st->chip_info->channels[i],
+ &st->pwr_down_mask, AD5686_PD_MSK_PWR_UP);
+ ad5686_pd_field_set(&st->chip_info->channels[i],
+ &st->pwr_down_mode, AD5686_PD_MODE_1K_TO_GND);
}

indio_dev->name = name;
diff --git a/drivers/iio/dac/ad5686.h b/drivers/iio/dac/ad5686.h
index caadc7403da1..176d41966985 100644
--- a/drivers/iio/dac/ad5686.h
+++ b/drivers/iio/dac/ad5686.h
@@ -35,11 +35,6 @@
#define AD5686_CMD_DAISY_CHAIN_ENABLE 0x8
#define AD5686_CMD_READBACK_ENABLE 0x9

-#define AD5686_LDAC_PWRDN_NONE 0x0
-#define AD5686_LDAC_PWRDN_1K 0x1
-#define AD5686_LDAC_PWRDN_100K 0x2
-#define AD5686_LDAC_PWRDN_3STATE 0x3
-
#define AD5686_CMD_CONTROL_REG 0x4
#define AD5686_CMD_READBACK_ENABLE_V2 0x5

@@ -47,6 +42,14 @@
#define AD5683_REF_BIT_MSK BIT(12)
#define AD5686_REF_BIT_MSK BIT(0)

+#define AD5686_PD_MSK GENMASK(1, 0)
+
+#define AD5686_PD_MODE_1K_TO_GND 0x1
+#define AD5686_PD_MODE_100K_TO_GND 0x2
+#define AD5686_PD_MODE_THREE_STATE 0x3
+
+#define AD5686_PD_MSK_PWR_UP 0x0
+#define AD5686_PD_MSK_PWR_DOWN 0x3

enum ad5686_regmap_type {
AD5310_REGMAP,

--
2.43.0