iio: hid-sensor-prox: Add support for more channels

Egis620 supports 3 channels: presense, proximity and attention.

Modify the driver so it can read those channels as well.

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Link: https://patch.msgid.link/20241101-hpd-v3-5-e9c80b7c7164@chromium.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

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

@@ -13,16 +13,32 @@
 #include <linux/iio/buffer.h>
 #include "../common/hid-sensors/hid-sensor-trigger.h"
 
-#define CHANNEL_SCAN_INDEX_PRESENCE 0
+static const u32 prox_usage_ids[] = {
+	HID_USAGE_SENSOR_HUMAN_PRESENCE,
+	HID_USAGE_SENSOR_HUMAN_PROXIMITY,
+	HID_USAGE_SENSOR_HUMAN_ATTENTION,
+};
+
+#define MAX_CHANNELS ARRAY_SIZE(prox_usage_ids)
+
+enum {
+	HID_HUMAN_PRESENCE,
+	HID_HUMAN_PROXIMITY,
+	HID_HUMAN_ATTENTION,
+};
 
 struct prox_state {
 	struct hid_sensor_hub_callbacks callbacks;
 	struct hid_sensor_common common_attributes;
-	struct hid_sensor_hub_attribute_info prox_attr;
+	struct hid_sensor_hub_attribute_info prox_attr[MAX_CHANNELS];
-	u32 human_presence;
+	struct iio_chan_spec channels[MAX_CHANNELS];
+	u32 channel2usage[MAX_CHANNELS];
+	u32 human_presence[MAX_CHANNELS];
 	int scale_pre_decml;
 	int scale_post_decml;
 	int scale_precision;
+	unsigned long scan_mask[2]; /* One entry plus one terminator. */
+	int num_channels;
 };
 
 static const u32 prox_sensitivity_addresses[] = {
@@ -30,18 +46,24 @@ static const u32 prox_sensitivity_addresses[] = {
 	HID_USAGE_SENSOR_DATA_PRESENCE,
 };
 
-/* Channel definitions */
+#define PROX_CHANNEL(_is_proximity, _channel) \
-static const struct iio_chan_spec prox_channels[] = {
+	{\
-	{
+		.type = _is_proximity ? IIO_PROXIMITY : IIO_ATTENTION,\
-		.type = IIO_PROXIMITY,
+		.info_mask_separate = _is_proximity ? BIT(IIO_CHAN_INFO_RAW) :\
-		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+				      BIT(IIO_CHAN_INFO_PROCESSED),\
-		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
+		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |\
-		BIT(IIO_CHAN_INFO_SCALE) |
+		BIT(IIO_CHAN_INFO_SCALE) |\
-		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+		BIT(IIO_CHAN_INFO_SAMP_FREQ) |\
-		BIT(IIO_CHAN_INFO_HYSTERESIS),
+		BIT(IIO_CHAN_INFO_HYSTERESIS),\
-		.scan_index = CHANNEL_SCAN_INDEX_PRESENCE,
+		.indexed = _is_proximity,\
-		.indexed = true,
+		.channel = _channel,\
 	}
+
+/* Channel definitions (same order as prox_usage_ids) */
+static const struct iio_chan_spec prox_channels[] = {
+	PROX_CHANNEL(true, HID_HUMAN_PRESENCE),
+	PROX_CHANNEL(true, HID_HUMAN_PROXIMITY),
+	PROX_CHANNEL(false, 0),
 };
 
 /* Adjust channel real bits based on report descriptor */
@@ -63,7 +85,7 @@ static int prox_read_raw(struct iio_dev *indio_dev,
 {
 	struct prox_state *prox_state = iio_priv(indio_dev);
 	struct hid_sensor_hub_device *hsdev;
-	int report_id = -1;
+	int report_id;
 	u32 address;
 	int ret_type;
 	s32 min;
@@ -72,29 +94,23 @@ static int prox_read_raw(struct iio_dev *indio_dev,
 	*val2 = 0;
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
-		switch (chan->scan_index) {
+		if (chan->scan_index >= prox_state->num_channels)
-		case  CHANNEL_SCAN_INDEX_PRESENCE:
-			report_id = prox_state->prox_attr.report_id;
-			min = prox_state->prox_attr.logical_minimum;
-			address = HID_USAGE_SENSOR_HUMAN_PRESENCE;
-			hsdev = prox_state->common_attributes.hsdev;
-			break;
-		default:
-			report_id = -1;
-			break;
-		}
-		if (report_id >= 0) {
-			hid_sensor_power_state(&prox_state->common_attributes,
-						true);
-			*val = sensor_hub_input_attr_get_raw_value(
-				hsdev, hsdev->usage, address, report_id,
-				SENSOR_HUB_SYNC, min < 0);
-			hid_sensor_power_state(&prox_state->common_attributes,
-						false);
-		} else {
-			*val = 0;
 			return -EINVAL;
-		}
+		address = prox_state->channel2usage[chan->scan_index];
+		report_id = prox_state->prox_attr[chan->scan_index].report_id;
+		hsdev = prox_state->common_attributes.hsdev;
+		min = prox_state->prox_attr[chan->scan_index].logical_minimum;
+		hid_sensor_power_state(&prox_state->common_attributes, true);
+		*val = sensor_hub_input_attr_get_raw_value(hsdev,
+							   hsdev->usage,
+							   address,
+							   report_id,
+							   SENSOR_HUB_SYNC,
+							   min < 0);
+		if (prox_state->channel2usage[chan->scan_index] ==
+		    HID_USAGE_SENSOR_HUMAN_ATTENTION)
+			*val *= 100;
+		hid_sensor_power_state(&prox_state->common_attributes, false);
 		ret_type = IIO_VAL_INT;
 		break;
 	case IIO_CHAN_INFO_SCALE:
@@ -104,7 +120,7 @@ static int prox_read_raw(struct iio_dev *indio_dev,
 		break;
 	case IIO_CHAN_INFO_OFFSET:
 		*val = hid_sensor_convert_exponent(
-				prox_state->prox_attr.unit_expo);
+			prox_state->prox_attr[chan->scan_index].unit_expo);
 		ret_type = IIO_VAL_INT;
 		break;
 	case IIO_CHAN_INFO_SAMP_FREQ:
@@ -179,48 +195,67 @@ static int prox_capture_sample(struct hid_sensor_hub_device *hsdev,
 {
 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
 	struct prox_state *prox_state = iio_priv(indio_dev);
-	int ret = -EINVAL;
+	int multiplier = 1;
+	int chan;
 
-	switch (usage_id) {
+	for (chan = 0; chan < prox_state->num_channels; chan++)
-	case HID_USAGE_SENSOR_HUMAN_PRESENCE:
+		if (prox_state->channel2usage[chan] == usage_id)
-		switch (raw_len) {
-		case 1:
-			prox_state->human_presence = *(u8 *)raw_data;
-			return 0;
-		case 4:
-			prox_state->human_presence = *(u32 *)raw_data;
-			return 0;
-		default:
 			break;
-		}
+	if (chan == prox_state->num_channels)
-		break;
+		return -EINVAL;
+
+	if (usage_id == HID_USAGE_SENSOR_HUMAN_ATTENTION)
+		multiplier = 100;
+
+	switch (raw_len) {
+	case 1:
+		prox_state->human_presence[chan] = *(u8 *)raw_data * multiplier;
+		return 0;
+	case 4:
+		prox_state->human_presence[chan] = *(u32 *)raw_data * multiplier;
+		return 0;
 	}
 
-	return ret;
+	return -EINVAL;
 }
 
 /* Parse report which is specific to an usage id*/
 static int prox_parse_report(struct platform_device *pdev,
 				struct hid_sensor_hub_device *hsdev,
-				struct iio_chan_spec *channels,
-				unsigned usage_id,
 				struct prox_state *st)
 {
+	struct iio_chan_spec *channels = st->channels;
+	int index = 0;
 	int ret;
+	int i;
 
-	ret = sensor_hub_input_get_attribute_info(hsdev, HID_INPUT_REPORT,
+	for (i = 0; i < MAX_CHANNELS; i++) {
-			usage_id,
+		u32 usage_id = prox_usage_ids[i];
-			HID_USAGE_SENSOR_HUMAN_PRESENCE,
+
-			&st->prox_attr);
+		ret = sensor_hub_input_get_attribute_info(hsdev,
-	if (ret < 0)
+							  HID_INPUT_REPORT,
+							  hsdev->usage,
+							  usage_id,
+							  &st->prox_attr[index]);
+		if (ret < 0)
+			continue;
+		st->channel2usage[index] = usage_id;
+		st->scan_mask[0] |= BIT(index);
+		channels[index] = prox_channels[i];
+		channels[index].scan_index = index;
+		prox_adjust_channel_bit_mask(channels, index,
+					     st->prox_attr[index].size);
+		dev_dbg(&pdev->dev, "prox %x:%x\n", st->prox_attr[index].index,
+			st->prox_attr[index].report_id);
+		index++;
+	}
+
+	if (!index)
 		return ret;
-	prox_adjust_channel_bit_mask(channels, CHANNEL_SCAN_INDEX_PRESENCE,
-					st->prox_attr.size);
 
-	dev_dbg(&pdev->dev, "prox %x:%x\n", st->prox_attr.index,
+	st->num_channels = index;
-			st->prox_attr.report_id);
 
-	return ret;
+	return 0;
 }
 
 /* Function to initialize the processing for usage id */
@@ -251,22 +286,15 @@ static int hid_prox_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	indio_dev->channels = devm_kmemdup(&pdev->dev, prox_channels,
+	ret = prox_parse_report(pdev, hsdev, prox_state);
-					   sizeof(prox_channels), GFP_KERNEL);
-	if (!indio_dev->channels) {
-		dev_err(&pdev->dev, "failed to duplicate channels\n");
-		return -ENOMEM;
-	}
-
-	ret = prox_parse_report(pdev, hsdev,
-				(struct iio_chan_spec *)indio_dev->channels,
-				hsdev->usage, prox_state);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to setup attributes\n");
 		return ret;
 	}
 
-	indio_dev->num_channels = ARRAY_SIZE(prox_channels);
+	indio_dev->num_channels = prox_state->num_channels;
+	indio_dev->channels = prox_state->channels;
+	indio_dev->available_scan_masks = prox_state->scan_mask;
 	indio_dev->info = &prox_info;
 	indio_dev->name = name;
 	indio_dev->modes = INDIO_DIRECT_MODE;