iio: light: vcnl4000: Add proximity irq for vcnl4200

Add proximity interrupt support for vcnl4200 (similar to vcnl4040).
Add support to configure proximity sensor interrupts and threshold
limits. If an interrupt is detected an event will be pushed to the
event interface.
Signed-off-by: Astrid Rost <astrid.rost@axis.com>
Link: https://lore.kernel.org/r/20230613135025.2596641-2-astrid.rost@axis.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/light/vcnl4000.c

@@ -65,6 +65,7 @@
 #define VCNL4200_PS_DATA	0x08 /* Proximity data */
 #define VCNL4200_AL_DATA	0x09 /* Ambient light data */
 #define VCNL4040_INT_FLAGS	0x0b /* Interrupt register */
+#define VCNL4200_INT_FLAGS	0x0d /* Interrupt register */
 #define VCNL4200_DEV_ID		0x0e /* Device ID, slave address and version */
 
 #define VCNL4040_DEV_ID		0x0c /* Device ID and version */
@@ -164,6 +165,8 @@ struct vcnl4000_chip_spec {
 	int (*set_power_state)(struct vcnl4000_data *data, bool on);
 	irqreturn_t (*irq_thread)(int irq, void *priv);
 	irqreturn_t (*trig_buffer_func)(int irq, void *priv);
+
+	u8 int_reg;
 };
 
 static const struct i2c_device_id vcnl4000_id[] = {
@@ -1005,7 +1008,7 @@ static irqreturn_t vcnl4040_irq_thread(int irq, void *p)
 	struct vcnl4000_data *data = iio_priv(indio_dev);
 	int ret;
 
-	ret = i2c_smbus_read_word_data(data->client, VCNL4040_INT_FLAGS);
+	ret = i2c_smbus_read_word_data(data->client, data->chip_spec->int_reg);
 	if (ret < 0)
 		return IRQ_HANDLED;
 
@@ -1314,6 +1317,7 @@ static const struct vcnl4000_chip_spec vcnl4000_chip_spec_cfg[] = {
 		.num_channels = ARRAY_SIZE(vcnl4040_channels),
 		.info = &vcnl4040_info,
 		.irq_thread = vcnl4040_irq_thread,
+		.int_reg = VCNL4040_INT_FLAGS,
 	},
 	[VCNL4200] = {
 		.prod = "VCNL4200",
@@ -1321,9 +1325,11 @@ static const struct vcnl4000_chip_spec vcnl4000_chip_spec_cfg[] = {
 		.measure_light = vcnl4200_measure_light,
 		.measure_proximity = vcnl4200_measure_proximity,
 		.set_power_state = vcnl4200_set_power_state,
-		.channels = vcnl4000_channels,
+		.channels = vcnl4040_channels,
 		.num_channels = ARRAY_SIZE(vcnl4000_channels),
-		.info = &vcnl4000_info,
+		.info = &vcnl4040_info,
+		.irq_thread = vcnl4040_irq_thread,
+		.int_reg = VCNL4200_INT_FLAGS,
 	},
 };