iio:dac:ad5686: Add support for various number of channels

This patch adds a new num_channels attribute as part of the
ad5686_chip_info struct which replaces the AD5686_DAC_CHANNELS define. This
is a necessary step, since this driver should support similar devices which
differ only in the number of channels.

Signed-off-by: Stefan Popa <stefan.popa@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/dac/ad5686.c b/drivers/iio/dac/ad5686.c
index e328513dd4c25baba45ff84a8f756338a49ee007..87d6e6e3d298e6ccecffba93919a19f946326eee 100644 (file)
--- a/drivers/iio/dac/ad5686.c
+++ b/drivers/iio/dac/ad5686.c
@@ -18,8 +18,6 @@
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
 
-#define AD5686_DAC_CHANNELS                    4
-
 #define AD5686_ADDR(x)                         ((x) << 16)
 #define AD5686_CMD(x)                          ((x) << 20)
 
@@ -45,12 +43,14 @@
 /**
  * struct ad5686_chip_info - chip specific information
  * @int_vref_mv:       AD5620/40/60: the internal reference voltage
+ * @num_channels:      number of channels
  * @channel:           channel specification
 */
 
 struct ad5686_chip_info {
        u16                             int_vref_mv;
-       struct iio_chan_spec            channel[AD5686_DAC_CHANNELS];
+       unsigned int                    num_channels;
+       struct iio_chan_spec            *channels;
 };
 
 /**
@@ -268,14 +268,14 @@ static const struct iio_chan_spec_ext_info ad5686_ext_info[] = {
        { },
 };
 
-#define AD5868_CHANNEL(chan, bits, _shift) {                   \
+#define AD5868_CHANNEL(chan, addr, bits, _shift) {             \
                .type = IIO_VOLTAGE,                            \
                .indexed = 1,                                   \
                .output = 1,                                    \
                .channel = chan,                                \
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),   \
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
-               .address = AD5686_ADDR_DAC(chan),               \
+               .address = addr,                                \
                .scan_type = {                                  \
                        .sign = 'u',                            \
                        .realbits = (bits),                     \
@@ -285,31 +285,36 @@ static const struct iio_chan_spec_ext_info ad5686_ext_info[] = {
                .ext_info = ad5686_ext_info,                    \
 }
 
+#define DECLARE_AD5686_CHANNELS(name, bits, _shift)            \
+static struct iio_chan_spec name[] = {                         \
+               AD5868_CHANNEL(0, 1, bits, _shift),             \
+               AD5868_CHANNEL(1, 2, bits, _shift),             \
+               AD5868_CHANNEL(2, 4, bits, _shift),             \
+               AD5868_CHANNEL(3, 8, bits, _shift),             \
+}
+
+DECLARE_AD5686_CHANNELS(ad5684_channels, 12, 4);
+DECLARE_AD5686_CHANNELS(ad5685r_channels, 14, 2);
+DECLARE_AD5686_CHANNELS(ad5686_channels, 16, 0);
+
 static const struct ad5686_chip_info ad5686_chip_info_tbl[] = {
        [ID_AD5684] = {
-               .channel[0] = AD5868_CHANNEL(0, 12, 4),
-               .channel[1] = AD5868_CHANNEL(1, 12, 4),
-               .channel[2] = AD5868_CHANNEL(2, 12, 4),
-               .channel[3] = AD5868_CHANNEL(3, 12, 4),
+               .channels = ad5684_channels,
+               .num_channels = 4,
                .int_vref_mv = 2500,
        },
        [ID_AD5685] = {
-               .channel[0] = AD5868_CHANNEL(0, 14, 2),
-               .channel[1] = AD5868_CHANNEL(1, 14, 2),
-               .channel[2] = AD5868_CHANNEL(2, 14, 2),
-               .channel[3] = AD5868_CHANNEL(3, 14, 2),
+               .channels = ad5685r_channels,
                .int_vref_mv = 2500,
+               .num_channels = 4,
        },
        [ID_AD5686] = {
-               .channel[0] = AD5868_CHANNEL(0, 16, 0),
-               .channel[1] = AD5868_CHANNEL(1, 16, 0),
-               .channel[2] = AD5868_CHANNEL(2, 16, 0),
-               .channel[3] = AD5868_CHANNEL(3, 16, 0),
+               .channels = ad5686_channels,
+               .num_channels = 4,
                .int_vref_mv = 2500,
        },
 };
 
-
 static int ad5686_probe(struct spi_device *spi)
 {
        struct ad5686_state *st;
@@ -353,8 +358,8 @@ static int ad5686_probe(struct spi_device *spi)
        indio_dev->name = spi_get_device_id(spi)->name;
        indio_dev->info = &ad5686_info;
        indio_dev->modes = INDIO_DIRECT_MODE;
-       indio_dev->channels = st->chip_info->channel;
-       indio_dev->num_channels = AD5686_DAC_CHANNELS;
+       indio_dev->channels = st->chip_info->channels;
+       indio_dev->num_channels = st->chip_info->num_channels;
 
        ret = ad5686_spi_write(st, AD5686_CMD_INTERNAL_REFER_SETUP, 0,
                                !!voltage_uv, 0);