[PATCH 7/8] iio: adc: ad9467: cache the sample rate

Nuno Sa via B4 Relay
2024-04-19T15:36:52Z

From: Nuno Sa <nuno.sa@analog.com>

Since we allow to change the sampling frequency and do it with
clk_round_rate(), we can cache it and use on the read_raw() interface.
This will also be useful in a following patch supporting interface
calibration.

Signed-off-by: Nuno Sa <nuno.sa@analog.com>
---
drivers/iio/adc/ad9467.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/adc/ad9467.c b/drivers/iio/adc/ad9467.c
index 7475ec2a56c72..7db87ccc1ea4b 100644
--- a/drivers/iio/adc/ad9467.c
+++ b/drivers/iio/adc/ad9467.c
@@ -117,6 +117,7 @@ struct ad9467_state {
struct iio_backend *back;
struct spi_device *spi;
struct clk *clk;
+ unsigned long sample_rate;
unsigned int output_mode;
unsigned int (*scales)[2];

@@ -331,7 +332,7 @@ static int ad9467_read_raw(struct iio_dev *indio_dev,
case IIO_CHAN_INFO_SCALE:
return ad9467_get_scale(st, val, val2);
case IIO_CHAN_INFO_SAMP_FREQ:
- *val = clk_get_rate(st->clk);
+ *val = st->sample_rate;

return IIO_VAL_INT;
default:
@@ -346,6 +347,7 @@ static int ad9467_write_raw(struct iio_dev *indio_dev,
struct ad9467_state *st = iio_priv(indio_dev);
const struct ad9467_chip_info *info = st->info;
long r_clk;
+ int ret;

switch (mask) {
case IIO_CHAN_INFO_SCALE:
@@ -358,7 +360,12 @@ static int ad9467_write_raw(struct iio_dev *indio_dev,
return -EINVAL;
}

- return clk_set_rate(st->clk, r_clk);
+ ret = clk_set_rate(st->clk, r_clk);
+ if (ret)
+ return ret;
+
+ st->sample_rate = r_clk;
+ return 0;
default:
return -EINVAL;
}
@@ -543,6 +550,8 @@ static int ad9467_probe(struct spi_device *spi)
if (IS_ERR(st->clk))
return PTR_ERR(st->clk);

+ st->sample_rate = clk_get_rate(st->clk);
+
st->pwrdown_gpio = devm_gpiod_get_optional(&spi->dev, "powerdown",
GPIOD_OUT_LOW);
if (IS_ERR(st->pwrdown_gpio))

--
2.44.0