[PATCH V4 3/5] iio: adc: ad7124: Shift to dynamic allocation for channel configuration

From: Mircea Caprioru
Date: Tue Jun 25 2019 - 04:12:33 EST


This patch changes the channel configuration member of the device
structure from a fixed size array to a dynamic allocated one with a size
equal to the number of channels specified in the device tree. This will
ensure a more flexibility for compatible devices.

Ex. ad7124-4 - can have 4 differential or 8 pseudo-differential channels
ad7124-8 - can have 8 differential or 16 pseudo-differential channels

Also the device can suspport any other combination of differential and
pseudo-differential channels base on the physical number of inputs
available.

Signed-off-by: Mircea Caprioru <mircea.caprioru@xxxxxxxxxx>
---

Changelog v2:
- nothing changed here

Changelog v3:
- nothing changed here

Changelog v4:
- nothing changed here

drivers/iio/adc/ad7124.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/adc/ad7124.c b/drivers/iio/adc/ad7124.c
index ab52c5e9ecb1..edc6f1cc90b2 100644
--- a/drivers/iio/adc/ad7124.c
+++ b/drivers/iio/adc/ad7124.c
@@ -121,7 +121,7 @@ struct ad7124_channel_config {
struct ad7124_state {
const struct ad7124_chip_info *chip_info;
struct ad_sigma_delta sd;
- struct ad7124_channel_config channel_config[4];
+ struct ad7124_channel_config *channel_config;
struct regulator *vref[4];
struct clk *mclk;
unsigned int adc_control;
@@ -439,6 +439,7 @@ static int ad7124_of_parse_channel_config(struct iio_dev *indio_dev,
struct ad7124_state *st = iio_priv(indio_dev);
struct device_node *child;
struct iio_chan_spec *chan;
+ struct ad7124_channel_config *chan_config;
unsigned int ain[2], channel = 0, tmp;
int ret;

@@ -453,8 +454,14 @@ static int ad7124_of_parse_channel_config(struct iio_dev *indio_dev,
if (!chan)
return -ENOMEM;

+ chan_config = devm_kcalloc(indio_dev->dev.parent, st->num_channels,
+ sizeof(*chan_config), GFP_KERNEL);
+ if (!chan_config)
+ return -ENOMEM;
+
indio_dev->channels = chan;
indio_dev->num_channels = st->num_channels;
+ st->channel_config = chan_config;

for_each_available_child_of_node(np, child) {
ret = of_property_read_u32(child, "reg", &channel);
--
2.17.1