iio: potentiometer: ds1803: Add channel information in device data

Adding each device wiper count and channel information into
device private data.
Utilizing addr member of struct iio_chan_spec to get the
wiper register address so that the value can be read or write
to the same address.

Signed-off-by: Jagath Jog J <jagathjog1996@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220223163525.13399-4-jagathjog1996@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/potentiometer/ds1803.c b/drivers/iio/potentiometer/ds1803.c
index 2861c4d..31ca87d 100644 (file)
--- a/drivers/iio/potentiometer/ds1803.c
+++ b/drivers/iio/potentiometer/ds1803.c
@@ -16,7 +16,8 @@
 #include <linux/module.h>
 #include <linux/mod_devicetable.h>
 
-#define DS1803_WRITE(chan)     (0xa8 | ((chan) + 1))
+#define DS1803_WIPER_0         0xA9
+#define DS1803_WIPER_1         0xAA
 
 enum ds1803_type {
        DS1803_010,
@@ -25,8 +26,11 @@ enum ds1803_type {
 };
 
 struct ds1803_cfg {
+       int wipers;
        int avail[3];
        int kohms;
+       const struct iio_chan_spec *channels;
+       u8 num_channels;
 };
 
 struct ds1803_data {
@@ -34,33 +38,43 @@ struct ds1803_data {
        const struct ds1803_cfg *cfg;
 };
 
-#define DS1803_CHANNEL(ch) {                                           \
+#define DS1803_CHANNEL(ch, addr) {                                     \
        .type = IIO_RESISTANCE,                                         \
        .indexed = 1,                                                   \
        .output = 1,                                                    \
        .channel = (ch),                                                \
+       .address = (addr),                                              \
        .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),                   \
        .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),           \
        .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_RAW),   \
 }
 
 static const struct iio_chan_spec ds1803_channels[] = {
-       DS1803_CHANNEL(0),
-       DS1803_CHANNEL(1),
+       DS1803_CHANNEL(0, DS1803_WIPER_0),
+       DS1803_CHANNEL(1, DS1803_WIPER_1),
 };
 
 static const struct ds1803_cfg ds1803_cfg[] = {
        [DS1803_010] = {
+               .wipers = 2,
                .avail = { 0, 1, 255 },
                .kohms =  10,
+               .channels = ds1803_channels,
+               .num_channels = ARRAY_SIZE(ds1803_channels),
        },
        [DS1803_050] = {
+               .wipers = 2,
                .avail = { 0, 1, 255 },
                .kohms =  50,
+               .channels = ds1803_channels,
+               .num_channels = ARRAY_SIZE(ds1803_channels),
        },
        [DS1803_100] = {
+               .wipers = 2,
                .avail = { 0, 1, 255 },
                .kohms = 100,
+               .channels = ds1803_channels,
+               .num_channels = ARRAY_SIZE(ds1803_channels),
        },
 };
 
@@ -97,7 +111,7 @@ static int ds1803_write_raw(struct iio_dev *indio_dev,
                            int val, int val2, long mask)
 {
        struct ds1803_data *data = iio_priv(indio_dev);
-       int pot = chan->channel;
+       u8 addr = chan->address;
        int max_pos = data->cfg->avail[2];
 
        if (val2 != 0)
@@ -112,7 +126,7 @@ static int ds1803_write_raw(struct iio_dev *indio_dev,
                return -EINVAL;
        }
 
-       return i2c_smbus_write_byte_data(data->client, DS1803_WRITE(pot), val);
+       return i2c_smbus_write_byte_data(data->client, addr, val);
 }
 
 static int ds1803_read_avail(struct iio_dev *indio_dev,
@@ -155,8 +169,8 @@ static int ds1803_probe(struct i2c_client *client, const struct i2c_device_id *i
        data->cfg = &ds1803_cfg[id->driver_data];
 
        indio_dev->info = &ds1803_info;
-       indio_dev->channels = ds1803_channels;
-       indio_dev->num_channels = ARRAY_SIZE(ds1803_channels);
+       indio_dev->channels = data->cfg->channels;
+       indio_dev->num_channels = data->cfg->num_channels;
        indio_dev->name = client->name;
 
        return devm_iio_device_register(dev, indio_dev);