iio: adc: ad7091r: Set device mode through chip_info callback

AD7091R-5 devices have a few modes of operation (sample, command,
autocycle) which are set by writing to configuration register fields.
Follow up patches will add support for AD7091R-2/-4/-8 which don't have
those operation modes nor the register fields for setting them.
Make ad7091r_set_mode() a callback function of AD7091R chip_info struct
so the base driver can appropriately handle each design without having
to check which actual chip is connected.

Signed-off-by: Marcelo Schmitt <[e-mail]>
Link: https://lore.kernel.org/r/51403369[e-mail]
Signed-off-by: Jonathan Cameron <[e-mail]>

drivers/iio/adc/ad7091r-base.c

···
 #define AD7091R_REG_RESULT_CH_ID(x)	    (((x) >> 13) & 0x3)
 #define AD7091R_REG_RESULT_CONV_RESULT(x)   ((x) & 0xfff)
 
-/* AD7091R_REG_CONF */
-#define AD7091R_REG_CONF_ALERT_EN   BIT(4)
-#define AD7091R_REG_CONF_AUTO   BIT(8)
-#define AD7091R_REG_CONF_CMD    BIT(10)
-
-#define AD7091R_REG_CONF_MODE_MASK  \
-	(AD7091R_REG_CONF_AUTO | AD7091R_REG_CONF_CMD)
-
 const struct iio_event_spec ad7091r_events[] = {
 	{
 		.type = IIO_EV_TYPE_THRESH,
···
 	},
 };
 EXPORT_SYMBOL_NS_GPL(ad7091r_events, IIO_AD7091R);
-
-static int ad7091r_set_mode(struct ad7091r_state *st, enum ad7091r_mode mode)
-{
-	int ret, conf;
-
-	switch (mode) {
-	case AD7091R_MODE_SAMPLE:
-		conf = 0;
-		break;
-	case AD7091R_MODE_COMMAND:
-		conf = AD7091R_REG_CONF_CMD;
-		break;
-	case AD7091R_MODE_AUTOCYCLE:
-		conf = AD7091R_REG_CONF_AUTO;
-		break;
-	default:
-		return -EINVAL;
-	}
-
-	ret = regmap_update_bits(st->map, AD7091R_REG_CONF,
-				 AD7091R_REG_CONF_MODE_MASK, conf);
-	if (ret)
-		return ret;
-
-	st->mode = mode;
-
-	return 0;
-}
 
 static int ad7091r_set_channel(struct ad7091r_state *st, unsigned int channel)
 {
···
 	}
 
 	/* Use command mode by default to convert only desired channels*/
-	ret = ad7091r_set_mode(st, AD7091R_MODE_COMMAND);
+	ret = st->chip_info->set_mode(st, AD7091R_MODE_COMMAND);
 	if (ret)
 		return ret;
 

drivers/iio/adc/ad7091r-base.h

···
 #define AD7091R_REG_CH_HIGH_LIMIT(ch) ((ch) * 3 + 5)
 #define AD7091R_REG_CH_HYSTERESIS(ch) ((ch) * 3 + 6)
 
+/* AD7091R_REG_CONF */
 #define AD7091R_REG_CONF_INT_VREF	BIT(0)
+#define AD7091R_REG_CONF_ALERT_EN	BIT(4)
+#define AD7091R_REG_CONF_AUTO		BIT(8)
+#define AD7091R_REG_CONF_CMD		BIT(10)
+
+#define AD7091R_REG_CONF_MODE_MASK  \
+	(AD7091R_REG_CONF_AUTO | AD7091R_REG_CONF_CMD)
 
 /* AD7091R_REG_CH_LIMIT */
 #define AD7091R_HIGH_LIMIT		0xFFF
···
 	unsigned int num_channels;
 	const struct iio_chan_spec *channels;
 	unsigned int vref_mV;
+	int (*set_mode)(struct ad7091r_state *st, enum ad7091r_mode mode);
 };
 
 struct ad7091r_init_info {

drivers/iio/adc/ad7091r5.c

···
 	AD7091R_CHANNEL(3, 12, NULL, 0),
 };
 
+static int ad7091r5_set_mode(struct ad7091r_state *st, enum ad7091r_mode mode)
+{
+	int ret, conf;
+
+	switch (mode) {
+	case AD7091R_MODE_SAMPLE:
+		conf = 0;
+		break;
+	case AD7091R_MODE_COMMAND:
+		conf = AD7091R_REG_CONF_CMD;
+		break;
+	case AD7091R_MODE_AUTOCYCLE:
+		conf = AD7091R_REG_CONF_AUTO;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = regmap_update_bits(st->map, AD7091R_REG_CONF,
+				 AD7091R_REG_CONF_MODE_MASK, conf);
+	if (ret)
+		return ret;
+
+	st->mode = mode;
+
+	return 0;
+}
+
 static const struct ad7091r_chip_info ad7091r5_chip_info_irq = {
 	.name = "ad7091r-5",
 	.channels = ad7091r5_channels_irq,
 	.num_channels = ARRAY_SIZE(ad7091r5_channels_irq),
 	.vref_mV = 2500,
+	.set_mode = &ad7091r5_set_mode,
 };
 
 static const struct ad7091r_chip_info ad7091r5_chip_info_noirq = {
···
 	.channels = ad7091r5_channels_noirq,
 	.num_channels = ARRAY_SIZE(ad7091r5_channels_noirq),
 	.vref_mV = 2500,
+	.set_mode = &ad7091r5_set_mode,
 };
 
 static const struct regmap_config ad7091r_regmap_config = {