iio: adc: ad7606: Move oversampling and scale options to chip info

The device dependent options which are going to be different for devices
which will be supported  in the future by this driver,
were moved in chip info for a more generic driver. This patch allows
supporting more devices by the driver. Also, it is an intermediate
step of adding support for ad7616 in software mode.
Signed-off-by: Beniamin Bia <beniamin.bia@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/adc/ad7606.c

@@ -158,7 +158,7 @@ static int ad7606_read_raw(struct iio_dev *indio_dev,
 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_SCALE:
 		*val = 0;
-		*val2 = st->scale_avail[st->range];
+		*val2 = st->scale_avail[st->range[0]];
 		return IIO_VAL_INT_PLUS_MICRO;
 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
 		*val = st->oversampling;
@@ -194,6 +194,32 @@ static ssize_t in_voltage_scale_available_show(struct device *dev,
 
 static IIO_DEVICE_ATTR_RO(in_voltage_scale_available, 0);
 
+static int ad7606_write_scale_hw(struct iio_dev *indio_dev, int ch, int val)
+{
+	struct ad7606_state *st = iio_priv(indio_dev);
+
+	gpiod_set_value(st->gpio_range, val);
+
+	return 0;
+}
+
+static int ad7606_write_os_hw(struct iio_dev *indio_dev, int val)
+{
+	struct ad7606_state *st = iio_priv(indio_dev);
+	DECLARE_BITMAP(values, 3);
+
+	values[0] = val;
+
+	gpiod_set_array_value(ARRAY_SIZE(values), st->gpio_os->desc,
+			      st->gpio_os->info, values);
+
+	/* AD7616 requires a reset to update value */
+	if (st->chip_info->os_req_reset)
+		ad7606_reset(st);
+
+	return 0;
+}
+
 static int ad7606_write_raw(struct iio_dev *indio_dev,
 			    struct iio_chan_spec const *chan,
 			    int val,
@@ -201,15 +227,18 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
 			    long mask)
 {
 	struct ad7606_state *st = iio_priv(indio_dev);
-	DECLARE_BITMAP(values, 3);
-	int i;
+	int i, ret, ch = 0;
 
 	switch (mask) {
 	case IIO_CHAN_INFO_SCALE:
 		mutex_lock(&st->lock);
 		i = find_closest(val2, st->scale_avail, st->num_scales);
-		gpiod_set_value(st->gpio_range, i);
-		st->range = i;
+		ret = st->write_scale(indio_dev, chan->address, i);
+		if (ret < 0) {
+			mutex_unlock(&st->lock);
+			return ret;
+		}
+		st->range[ch] = i;
 		mutex_unlock(&st->lock);
 
 		return 0;
@@ -218,17 +247,12 @@ static int ad7606_write_raw(struct iio_dev *indio_dev,
 			return -EINVAL;
 		i = find_closest(val, st->oversampling_avail,
 				 st->num_os_ratios);
-
-		values[0] = i;
-
 		mutex_lock(&st->lock);
-		gpiod_set_array_value(ARRAY_SIZE(values), st->gpio_os->desc,
-				      st->gpio_os->info, values);
-
-		/* AD7616 requires a reset to update value */
-		if (st->chip_info->os_req_reset)
-			ad7606_reset(st);
-
+		ret = st->write_os(indio_dev, i);
+		if (ret < 0) {
+			mutex_unlock(&st->lock);
+			return ret;
+		}
 		st->oversampling = st->oversampling_avail[i];
 		mutex_unlock(&st->lock);
 
@@ -536,7 +560,7 @@ int ad7606_probe(struct device *dev, int irq, void __iomem *base_address,
 	st->bops = bops;
 	st->base_address = base_address;
 	/* tied to logic low, analog input range is +/- 5V */
-	st->range = 0;
+	st->range[0] = 0;
 	st->oversampling = 1;
 	st->scale_avail = ad7606_scale_avail;
 	st->num_scales = ARRAY_SIZE(ad7606_scale_avail);
@@ -589,6 +613,9 @@ int ad7606_probe(struct device *dev, int irq, void __iomem *base_address,
 	if (ret)
 		dev_warn(st->dev, "failed to RESET: no RESET GPIO specified\n");
 
+	st->write_scale = ad7606_write_scale_hw;
+	st->write_os = ad7606_write_os_hw;
+
 	st->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
 					  indio_dev->name, indio_dev->id);
 	if (!st->trig)
@@ -643,7 +670,7 @@ static int ad7606_resume(struct device *dev)
 	struct ad7606_state *st = iio_priv(indio_dev);
 
 	if (st->gpio_standby) {
-		gpiod_set_value(st->gpio_range, st->range);
+		gpiod_set_value(st->gpio_range, st->range[0]);
 		gpiod_set_value(st->gpio_standby, 1);
 		ad7606_reset(st);
 	}

drivers/iio/adc/ad7606.h

@@ -16,6 +16,12 @@
  *			oversampling ratios.
  * @oversampling_num	number of elements stored in oversampling_avail array
  * @os_req_reset	some devices require a reset to update oversampling
+ * @write_scale_sw	pointer to the function which writes the scale via spi
+			in software mode
+ * @write_os_sw		pointer to the function which writes the os via spi
+			in software mode
+ * @sw_mode_config:	pointer to a function which configured the device
+ *			for software mode
  */
 struct ad7606_chip_info {
 	const struct iio_chan_spec	*channels;
@@ -23,6 +29,9 @@ struct ad7606_chip_info {
 	const unsigned int		*oversampling_avail;
 	unsigned int			oversampling_num;
 	bool				os_req_reset;
+	int (*write_scale_sw)(struct iio_dev *indio_dev, int ch, int val);
+	int (*write_os_sw)(struct iio_dev *indio_dev, int val);
+	int (*sw_mode_config)(struct iio_dev *indio_dev);
 };
 
 /**
@@ -39,6 +48,8 @@ struct ad7606_chip_info {
  * @oversampling_avail	pointer to the array which stores the available
  *			oversampling ratios.
  * @num_os_ratios	number of elements stored in oversampling_avail array
+ * @write_scale		pointer to the function which writes the scale
+ * @write_os		pointer to the function which writes the os
  * @lock		protect sensor state from concurrent accesses to GPIOs
  * @gpio_convst	GPIO descriptor for conversion start signal (CONVST)
  * @gpio_reset		GPIO descriptor for device hard-reset
@@ -57,13 +68,15 @@ struct ad7606_state {
 	const struct ad7606_chip_info	*chip_info;
 	struct regulator		*reg;
 	const struct ad7606_bus_ops	*bops;
-	unsigned int			range;
+	unsigned int			range[16];
 	unsigned int			oversampling;
 	void __iomem			*base_address;
 	const unsigned int		*scale_avail;
 	unsigned int			num_scales;
 	const unsigned int		*oversampling_avail;
 	unsigned int			num_os_ratios;
+	int (*write_scale)(struct iio_dev *indio_dev, int ch, int val);
+	int (*write_os)(struct iio_dev *indio_dev, int val);
 
 	struct mutex			lock; /* protect sensor state */
 	struct gpio_desc		*gpio_convst;