iio: hid-sensor-als: Use channel index to support more hub attributes

Sensor hub attributes can be extended to support more channels. Repeat
the reading for the two existing channels and store them separately. It
still operates in the same manner as before where there was just one
entry. So in order to support more sensor hub attributes for ALS use
channel index to get specific sensor hub attributes.
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Acked-by: Srinivas Pandruvada<srinivas.pandruvada@linux.intel.com>
Link: https://lore.kernel.org/r/20230919081054.2050714-2-Basavaraj.Natikar@amd.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/light/hid-sensor-als.c

@@ -24,7 +24,7 @@ enum {
 struct als_state {
 	struct hid_sensor_hub_callbacks callbacks;
 	struct hid_sensor_common common_attributes;
-	struct hid_sensor_hub_attribute_info als_illum;
+	struct hid_sensor_hub_attribute_info als[CHANNEL_SCAN_INDEX_MAX];
 	struct {
 		u32 illum[CHANNEL_SCAN_INDEX_MAX];
 		u64 timestamp __aligned(8);
@@ -99,8 +99,8 @@ static int als_read_raw(struct iio_dev *indio_dev,
 		switch (chan->scan_index) {
 		case  CHANNEL_SCAN_INDEX_INTENSITY:
 		case  CHANNEL_SCAN_INDEX_ILLUM:
-			report_id = als_state->als_illum.report_id;
-			min = als_state->als_illum.logical_minimum;
+			report_id = als_state->als[chan->scan_index].report_id;
+			min = als_state->als[chan->scan_index].logical_minimum;
 			address = HID_USAGE_SENSOR_LIGHT_ILLUM;
 			break;
 		default:
@@ -242,22 +242,24 @@ static int als_parse_report(struct platform_device *pdev,
 				struct als_state *st)
 {
 	int ret;
+	int i;
+
+	for (i = 0; i <= CHANNEL_SCAN_INDEX_ILLUM; ++i) {
+		ret = sensor_hub_input_get_attribute_info(hsdev,
+						HID_INPUT_REPORT,
+						usage_id,
+						HID_USAGE_SENSOR_LIGHT_ILLUM,
+						&st->als[i]);
+		if (ret < 0)
+			return ret;
+		als_adjust_channel_bit_mask(channels, i, st->als[i].size);
+
+		dev_dbg(&pdev->dev, "als %x:%x\n", st->als[i].index,
+			st->als[i].report_id);
+	}
 
-	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
-			usage_id,
-			HID_USAGE_SENSOR_LIGHT_ILLUM,
-			&st->als_illum);
-	if (ret < 0)
-		return ret;
-	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_INTENSITY,
-				    st->als_illum.size);
-	als_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_ILLUM,
-					st->als_illum.size);
-
-	dev_dbg(&pdev->dev, "als %x:%x\n", st->als_illum.index,
-			st->als_illum.report_id);
-
-	st->scale_precision = hid_sensor_format_scale(usage_id, &st->als_illum,
+	st->scale_precision = hid_sensor_format_scale(usage_id,
+				&st->als[CHANNEL_SCAN_INDEX_INTENSITY],
 				&st->scale_pre_decml, &st->scale_post_decml);
 
 	return ret;