[PATCH v4 0/4] Add support of color temperature and chromaticity

[PATCH v4 0/4] Add support of color temperature and chromaticity

[Srinivas Pandruvada]

The original series submitted to 6.7 (before revert) is modified to
solve regression issues on several platforms. There are two changes
introduced before adding support for new features to allow dynamic
addition of channels.

v4:
Addressed comments from Jonathan and Basavaraj
v3:
Addressed comments for v2, details in each patch.
v2:
New change to add channels dynamically
Modified color temperature and chromaticity to skip in case
of failures


Basavaraj Natikar (2):
  iio: hid-sensor-als: Add light color temperature support
  iio: hid-sensor-als: Add light chromaticity support

Srinivas Pandruvada (2):
  iio: hid-sensor-als: Assign channels dynamically
  iio: hid-sensor-als: Remove hardcoding of values for enums

 drivers/iio/light/hid-sensor-als.c | 123 ++++++++++++++++++++++++-----
 include/linux/hid-sensor-ids.h     |   4 +
 2 files changed, 109 insertions(+), 18 deletions(-)

-- 
2.43.0

[PATCH v4 1/4] iio: hid-sensor-als: Assign channels dynamically

[Srinivas Pandruvada]

Instead of assuming that every channel defined statically by
als_channels[] is present, assign dynamically based on presence of the
respective usage id in the descriptor. This will allow to register ALS
with limited channel support. Append the timestamp as the last channel.

Update available_scan_mask to specify all channels which are present.

There is no intentional function changes done.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
v4:
Addressed comments from Jonthan:
	- Use available_scan_masks
	- timestamp location is fixed and left gaps in sample data for absent channels
	- Use CHANNEL_SCAN_INDEX_MAX as limit to check presence of usage ids, otherwise
	  it will miss newer channels added in subsequent patches.
v3:
Addressed comments from Jonthan:
	- Remove channel allocation and move to iio_priv()
	- Parse all usage IDs in a single loop and continue
	for failure. This way the temperature and chromaticity
	will not need any special processing to parse usage ids.
	- Don't leave empty channel indexes

v2:
New change

 drivers/iio/light/hid-sensor-als.c | 52 +++++++++++++++++++++---------
 1 file changed, 36 insertions(+), 16 deletions(-)

diff --git a/drivers/iio/light/hid-sensor-als.c b/drivers/iio/light/hid-sensor-als.c
index b6c4bef2a7bb..d3b892c0e307 100644
--- a/drivers/iio/light/hid-sensor-als.c
+++ b/drivers/iio/light/hid-sensor-als.c
@@ -25,6 +25,7 @@ struct als_state {
 	struct hid_sensor_hub_callbacks callbacks;
 	struct hid_sensor_common common_attributes;
 	struct hid_sensor_hub_attribute_info als[CHANNEL_SCAN_INDEX_MAX];
+	struct iio_chan_spec channels[CHANNEL_SCAN_INDEX_MAX + 1];
 	struct {
 		u32 illum[CHANNEL_SCAN_INDEX_MAX];
 		u64 timestamp __aligned(8);
@@ -33,9 +34,16 @@ struct als_state {
 	int scale_post_decml;
 	int scale_precision;
 	int value_offset;
+	int num_channels;
 	s64 timestamp;
 };
 
+/* The order of usage ids must match scan index starting from CHANNEL_SCAN_INDEX_INTENSITY */
+static const u32 als_usage_ids[] = {
+	HID_USAGE_SENSOR_LIGHT_ILLUM,
+	HID_USAGE_SENSOR_LIGHT_ILLUM,
+};
+
 static const u32 als_sensitivity_addresses[] = {
 	HID_USAGE_SENSOR_DATA_LIGHT,
 	HID_USAGE_SENSOR_LIGHT_ILLUM,
@@ -68,6 +76,8 @@ static const struct iio_chan_spec als_channels[] = {
 	IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)
 };
 
+static unsigned long als_scan_mask[] = {0, 0};
+
 /* Adjust channel real bits based on report descriptor */
 static void als_adjust_channel_bit_mask(struct iio_chan_spec *channels,
 					int channel, int size)
@@ -238,27 +248,38 @@ static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
 /* Parse report which is specific to an usage id*/
 static int als_parse_report(struct platform_device *pdev,
 				struct hid_sensor_hub_device *hsdev,
-				struct iio_chan_spec *channels,
 				unsigned usage_id,
 				struct als_state *st)
 {
-	int ret;
+	struct iio_chan_spec *channels;
+	int ret, index = 0;
 	int i;
 
-	for (i = 0; i <= CHANNEL_SCAN_INDEX_ILLUM; ++i) {
+	channels = st->channels;
+
+	for (i = 0; i < CHANNEL_SCAN_INDEX_MAX; ++i) {
 		ret = sensor_hub_input_get_attribute_info(hsdev,
 						HID_INPUT_REPORT,
 						usage_id,
-						HID_USAGE_SENSOR_LIGHT_ILLUM,
+						als_usage_ids[i],
 						&st->als[i]);
 		if (ret < 0)
-			return ret;
-		als_adjust_channel_bit_mask(channels, i, st->als[i].size);
+			continue;
+
+		channels[index] = als_channels[i];
+		als_scan_mask[0] |= BIT(i);
+		als_adjust_channel_bit_mask(channels, index, st->als[i].size);
+		++index;
 
 		dev_dbg(&pdev->dev, "als %x:%x\n", st->als[i].index,
 			st->als[i].report_id);
 	}
 
+	st->num_channels = index;
+	/* Return success even if one usage id is present */
+	if (index)
+		ret = 0;
+
 	st->scale_precision = hid_sensor_format_scale(usage_id,
 				&st->als[CHANNEL_SCAN_INDEX_INTENSITY],
 				&st->scale_pre_decml, &st->scale_post_decml);
@@ -294,15 +315,7 @@ static int hid_als_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	indio_dev->channels = devm_kmemdup(&pdev->dev, als_channels,
-					   sizeof(als_channels), GFP_KERNEL);
-	if (!indio_dev->channels) {
-		dev_err(&pdev->dev, "failed to duplicate channels\n");
-		return -ENOMEM;
-	}
-
 	ret = als_parse_report(pdev, hsdev,
-			       (struct iio_chan_spec *)indio_dev->channels,
 			       hsdev->usage,
 			       als_state);
 	if (ret) {
@@ -310,8 +323,15 @@ static int hid_als_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	indio_dev->num_channels =
-				ARRAY_SIZE(als_channels);
+	/* Add timestamp channel */
+	als_state->channels[als_state->num_channels] = als_channels[CHANNEL_SCAN_INDEX_TIMESTAMP];
+
+	/* +1 for adding timestamp channel */
+	indio_dev->num_channels = als_state->num_channels + 1;
+
+	indio_dev->channels = als_state->channels;
+	indio_dev->available_scan_masks = als_scan_mask;
+
 	indio_dev->info = &als_info;
 	indio_dev->name = name;
 	indio_dev->modes = INDIO_DIRECT_MODE;
-- 
2.43.0

[PATCH v4 2/4] iio: hid-sensor-als: Remove hardcoding of values for enums

[Srinivas Pandruvada]

Remove hardcoding of values for enum CHANNEL_SCAN_INDEX_INTENSITY and
CHANNEL_SCAN_INDEX_ILLUM.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
v4:
	NO change

v3:
New patch. Added as the next patch removed the hardcoding of enum values
when submitted. To remove unrelated changes, created a patch to just
remove hardcoding of values.

 drivers/iio/light/hid-sensor-als.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/light/hid-sensor-als.c b/drivers/iio/light/hid-sensor-als.c
index d3b892c0e307..521af52b3f3b 100644
--- a/drivers/iio/light/hid-sensor-als.c
+++ b/drivers/iio/light/hid-sensor-als.c
@@ -14,8 +14,8 @@
 #include "../common/hid-sensors/hid-sensor-trigger.h"
 
 enum {
-	CHANNEL_SCAN_INDEX_INTENSITY = 0,
-	CHANNEL_SCAN_INDEX_ILLUM = 1,
+	CHANNEL_SCAN_INDEX_INTENSITY,
+	CHANNEL_SCAN_INDEX_ILLUM,
 	CHANNEL_SCAN_INDEX_MAX
 };
 
-- 
2.43.0

[PATCH v4 3/4] iio: hid-sensor-als: Add light color temperature support

[Srinivas Pandruvada]

From: Basavaraj Natikar <Basavaraj.Natikar@amd.com>

On some platforms, ambient color sensors also support light color
temperature. Add support of light color temperature.

Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
v4:
  - Index is fixed for each channel instead of packing for absent channels
v3:
Simplilified as no special processing is required in als_parse_report()
v2:
Original patch from Basavaraj Natikar <Basavaraj.Natikar@amd.com> is
modified to prevent failure when the new usage id is not found in the
descriptor.

 drivers/iio/light/hid-sensor-als.c | 21 +++++++++++++++++++++
 include/linux/hid-sensor-ids.h     |  1 +
 2 files changed, 22 insertions(+)

diff --git a/drivers/iio/light/hid-sensor-als.c b/drivers/iio/light/hid-sensor-als.c
index 521af52b3f3b..0e9a25c51676 100644
--- a/drivers/iio/light/hid-sensor-als.c
+++ b/drivers/iio/light/hid-sensor-als.c
@@ -16,6 +16,7 @@
 enum {
 	CHANNEL_SCAN_INDEX_INTENSITY,
 	CHANNEL_SCAN_INDEX_ILLUM,
+	CHANNEL_SCAN_INDEX_COLOR_TEMP,
 	CHANNEL_SCAN_INDEX_MAX
 };
 
@@ -42,6 +43,7 @@ struct als_state {
 static const u32 als_usage_ids[] = {
 	HID_USAGE_SENSOR_LIGHT_ILLUM,
 	HID_USAGE_SENSOR_LIGHT_ILLUM,
+	HID_USAGE_SENSOR_LIGHT_COLOR_TEMPERATURE,
 };
 
 static const u32 als_sensitivity_addresses[] = {
@@ -73,6 +75,16 @@ static const struct iio_chan_spec als_channels[] = {
 		BIT(IIO_CHAN_INFO_HYSTERESIS_RELATIVE),
 		.scan_index = CHANNEL_SCAN_INDEX_ILLUM,
 	},
+	{
+		.type = IIO_COLORTEMP,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
+		BIT(IIO_CHAN_INFO_SCALE) |
+		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+		BIT(IIO_CHAN_INFO_HYSTERESIS) |
+		BIT(IIO_CHAN_INFO_HYSTERESIS_RELATIVE),
+		.scan_index = CHANNEL_SCAN_INDEX_COLOR_TEMP,
+	},
 	IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)
 };
 
@@ -113,6 +125,11 @@ static int als_read_raw(struct iio_dev *indio_dev,
 			min = als_state->als[chan->scan_index].logical_minimum;
 			address = HID_USAGE_SENSOR_LIGHT_ILLUM;
 			break;
+		case  CHANNEL_SCAN_INDEX_COLOR_TEMP:
+			report_id = als_state->als[chan->scan_index].report_id;
+			min = als_state->als[chan->scan_index].logical_minimum;
+			address = HID_USAGE_SENSOR_LIGHT_COLOR_TEMPERATURE;
+			break;
 		default:
 			report_id = -1;
 			break;
@@ -233,6 +250,10 @@ static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
 		als_state->scan.illum[CHANNEL_SCAN_INDEX_ILLUM] = sample_data;
 		ret = 0;
 		break;
+	case HID_USAGE_SENSOR_LIGHT_COLOR_TEMPERATURE:
+		als_state->scan.illum[CHANNEL_SCAN_INDEX_COLOR_TEMP] = sample_data;
+		ret = 0;
+		break;
 	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
 		als_state->timestamp = hid_sensor_convert_timestamp(&als_state->common_attributes,
 								    *(s64 *)raw_data);
diff --git a/include/linux/hid-sensor-ids.h b/include/linux/hid-sensor-ids.h
index 13b1e65fbdcc..8af4fb3e0254 100644
--- a/include/linux/hid-sensor-ids.h
+++ b/include/linux/hid-sensor-ids.h
@@ -21,6 +21,7 @@
 #define HID_USAGE_SENSOR_ALS					0x200041
 #define HID_USAGE_SENSOR_DATA_LIGHT				0x2004d0
 #define HID_USAGE_SENSOR_LIGHT_ILLUM				0x2004d1
+#define HID_USAGE_SENSOR_LIGHT_COLOR_TEMPERATURE		0x2004d2
 
 /* PROX (200011) */
 #define HID_USAGE_SENSOR_PROX                                   0x200011
-- 
2.43.0

[PATCH v4 4/4] iio: hid-sensor-als: Add light chromaticity support

[Srinivas Pandruvada]

From: Basavaraj Natikar <Basavaraj.Natikar@amd.com>

On some platforms, ambient color sensors also support the x and y light
colors, which represent the coordinates on the CIE 1931 chromaticity
diagram. Add light chromaticity x and y.

Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
v4:
  - Index is fixed for each channel instead of packing for absent channels

v3:
Simplilified as no special processing is required in als_parse_report()

v2:
Original patch from Basavaraj Natikar <Basavaraj.Natikar@amd.com> is
modified to prevent failure when the new usage id is not found in the
descriptor.

 drivers/iio/light/hid-sensor-als.c | 46 ++++++++++++++++++++++++++++++
 include/linux/hid-sensor-ids.h     |  3 ++
 2 files changed, 49 insertions(+)

diff --git a/drivers/iio/light/hid-sensor-als.c b/drivers/iio/light/hid-sensor-als.c
index 0e9a25c51676..3c8f707c18cf 100644
--- a/drivers/iio/light/hid-sensor-als.c
+++ b/drivers/iio/light/hid-sensor-als.c
@@ -17,6 +17,8 @@ enum {
 	CHANNEL_SCAN_INDEX_INTENSITY,
 	CHANNEL_SCAN_INDEX_ILLUM,
 	CHANNEL_SCAN_INDEX_COLOR_TEMP,
+	CHANNEL_SCAN_INDEX_CHROMATICITY_X,
+	CHANNEL_SCAN_INDEX_CHROMATICITY_Y,
 	CHANNEL_SCAN_INDEX_MAX
 };
 
@@ -44,6 +46,8 @@ static const u32 als_usage_ids[] = {
 	HID_USAGE_SENSOR_LIGHT_ILLUM,
 	HID_USAGE_SENSOR_LIGHT_ILLUM,
 	HID_USAGE_SENSOR_LIGHT_COLOR_TEMPERATURE,
+	HID_USAGE_SENSOR_LIGHT_CHROMATICITY_X,
+	HID_USAGE_SENSOR_LIGHT_CHROMATICITY_Y,
 };
 
 static const u32 als_sensitivity_addresses[] = {
@@ -85,6 +89,30 @@ static const struct iio_chan_spec als_channels[] = {
 		BIT(IIO_CHAN_INFO_HYSTERESIS_RELATIVE),
 		.scan_index = CHANNEL_SCAN_INDEX_COLOR_TEMP,
 	},
+	{
+		.type = IIO_CHROMATICITY,
+		.modified = 1,
+		.channel2 = IIO_MOD_X,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
+		BIT(IIO_CHAN_INFO_SCALE) |
+		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+		BIT(IIO_CHAN_INFO_HYSTERESIS) |
+		BIT(IIO_CHAN_INFO_HYSTERESIS_RELATIVE),
+		.scan_index = CHANNEL_SCAN_INDEX_CHROMATICITY_X,
+	},
+	{
+		.type = IIO_CHROMATICITY,
+		.modified = 1,
+		.channel2 = IIO_MOD_Y,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
+		BIT(IIO_CHAN_INFO_SCALE) |
+		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+		BIT(IIO_CHAN_INFO_HYSTERESIS) |
+		BIT(IIO_CHAN_INFO_HYSTERESIS_RELATIVE),
+		.scan_index = CHANNEL_SCAN_INDEX_CHROMATICITY_Y,
+	},
 	IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)
 };
 
@@ -130,6 +158,16 @@ static int als_read_raw(struct iio_dev *indio_dev,
 			min = als_state->als[chan->scan_index].logical_minimum;
 			address = HID_USAGE_SENSOR_LIGHT_COLOR_TEMPERATURE;
 			break;
+		case  CHANNEL_SCAN_INDEX_CHROMATICITY_X:
+			report_id = als_state->als[chan->scan_index].report_id;
+			min = als_state->als[chan->scan_index].logical_minimum;
+			address = HID_USAGE_SENSOR_LIGHT_CHROMATICITY_X;
+			break;
+		case  CHANNEL_SCAN_INDEX_CHROMATICITY_Y:
+			report_id = als_state->als[chan->scan_index].report_id;
+			min = als_state->als[chan->scan_index].logical_minimum;
+			address = HID_USAGE_SENSOR_LIGHT_CHROMATICITY_Y;
+			break;
 		default:
 			report_id = -1;
 			break;
@@ -254,6 +292,14 @@ static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
 		als_state->scan.illum[CHANNEL_SCAN_INDEX_COLOR_TEMP] = sample_data;
 		ret = 0;
 		break;
+	case HID_USAGE_SENSOR_LIGHT_CHROMATICITY_X:
+		als_state->scan.illum[CHANNEL_SCAN_INDEX_CHROMATICITY_X] = sample_data;
+		ret = 0;
+		break;
+	case HID_USAGE_SENSOR_LIGHT_CHROMATICITY_Y:
+		als_state->scan.illum[CHANNEL_SCAN_INDEX_CHROMATICITY_Y] = sample_data;
+		ret = 0;
+		break;
 	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
 		als_state->timestamp = hid_sensor_convert_timestamp(&als_state->common_attributes,
 								    *(s64 *)raw_data);
diff --git a/include/linux/hid-sensor-ids.h b/include/linux/hid-sensor-ids.h
index 8af4fb3e0254..6730ee900ee1 100644
--- a/include/linux/hid-sensor-ids.h
+++ b/include/linux/hid-sensor-ids.h
@@ -22,6 +22,9 @@
 #define HID_USAGE_SENSOR_DATA_LIGHT				0x2004d0
 #define HID_USAGE_SENSOR_LIGHT_ILLUM				0x2004d1
 #define HID_USAGE_SENSOR_LIGHT_COLOR_TEMPERATURE		0x2004d2
+#define HID_USAGE_SENSOR_LIGHT_CHROMATICITY			0x2004d3
+#define HID_USAGE_SENSOR_LIGHT_CHROMATICITY_X			0x2004d4
+#define HID_USAGE_SENSOR_LIGHT_CHROMATICITY_Y			0x2004d5
 
 /* PROX (200011) */
 #define HID_USAGE_SENSOR_PROX                                   0x200011
-- 
2.43.0

Re: [PATCH v4 1/4] iio: hid-sensor-als: Assign channels dynamically

[Jonathan Cameron]

On Sun,  4 Feb 2024 05:03:29 -0800
Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> wrote:

> Instead of assuming that every channel defined statically by
> als_channels[] is present, assign dynamically based on presence of the
> respective usage id in the descriptor. This will allow to register ALS
> with limited channel support. Append the timestamp as the last channel.
> 
> Update available_scan_mask to specify all channels which are present.
> 
> There is no intentional function changes done.
> 
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Hi Srinivas,

Logic looks fine, but not that global variable...

> ---
> v4:
> Addressed comments from Jonthan:
> 	- Use available_scan_masks
> 	- timestamp location is fixed and left gaps in sample data for absent channels
> 	- Use CHANNEL_SCAN_INDEX_MAX as limit to check presence of usage ids, otherwise
> 	  it will miss newer channels added in subsequent patches.
> v3:
> Addressed comments from Jonthan:
> 	- Remove channel allocation and move to iio_priv()
> 	- Parse all usage IDs in a single loop and continue
> 	for failure. This way the temperature and chromaticity
> 	will not need any special processing to parse usage ids.
> 	- Don't leave empty channel indexes
> 
> v2:
> New change
> 
>  drivers/iio/light/hid-sensor-als.c | 52 +++++++++++++++++++++---------
>  1 file changed, 36 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/iio/light/hid-sensor-als.c b/drivers/iio/light/hid-sensor-als.c
> index b6c4bef2a7bb..d3b892c0e307 100644
> --- a/drivers/iio/light/hid-sensor-als.c
> +++ b/drivers/iio/light/hid-sensor-als.c
> @@ -25,6 +25,7 @@ struct als_state {
>  	struct hid_sensor_hub_callbacks callbacks;
>  	struct hid_sensor_common common_attributes;
>  	struct hid_sensor_hub_attribute_info als[CHANNEL_SCAN_INDEX_MAX];
> +	struct iio_chan_spec channels[CHANNEL_SCAN_INDEX_MAX + 1];
>  	struct {
>  		u32 illum[CHANNEL_SCAN_INDEX_MAX];
>  		u64 timestamp __aligned(8);
> @@ -33,9 +34,16 @@ struct als_state {
>  	int scale_post_decml;
>  	int scale_precision;
>  	int value_offset;
> +	int num_channels;
>  	s64 timestamp;
>  };
>  
> +/* The order of usage ids must match scan index starting from CHANNEL_SCAN_INDEX_INTENSITY */
> +static const u32 als_usage_ids[] = {
> +	HID_USAGE_SENSOR_LIGHT_ILLUM,
> +	HID_USAGE_SENSOR_LIGHT_ILLUM,
> +};
> +
>  static const u32 als_sensitivity_addresses[] = {
>  	HID_USAGE_SENSOR_DATA_LIGHT,
>  	HID_USAGE_SENSOR_LIGHT_ILLUM,
> @@ -68,6 +76,8 @@ static const struct iio_chan_spec als_channels[] = {
>  	IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)
>  };
>  
> +static unsigned long als_scan_mask[] = {0, 0};

Global? No. Could be multiple instances with different sensors supported.
Needs to be embedded in the als_state structure so it is per instance.

> +
>  /* Adjust channel real bits based on report descriptor */
>  static void als_adjust_channel_bit_mask(struct iio_chan_spec *channels,
>  					int channel, int size)
> @@ -238,27 +248,38 @@ static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
>  /* Parse report which is specific to an usage id*/
>  static int als_parse_report(struct platform_device *pdev,
>  				struct hid_sensor_hub_device *hsdev,
> -				struct iio_chan_spec *channels,
>  				unsigned usage_id,
>  				struct als_state *st)
>  {
> -	int ret;
> +	struct iio_chan_spec *channels;
> +	int ret, index = 0;
>  	int i;
>  
> -	for (i = 0; i <= CHANNEL_SCAN_INDEX_ILLUM; ++i) {
> +	channels = st->channels;
> +
> +	for (i = 0; i < CHANNEL_SCAN_INDEX_MAX; ++i) {
>  		ret = sensor_hub_input_get_attribute_info(hsdev,
>  						HID_INPUT_REPORT,
>  						usage_id,
> -						HID_USAGE_SENSOR_LIGHT_ILLUM,
> +						als_usage_ids[i],
>  						&st->als[i]);
>  		if (ret < 0)
> -			return ret;
> -		als_adjust_channel_bit_mask(channels, i, st->als[i].size);
> +			continue;
> +
> +		channels[index] = als_channels[i];
> +		als_scan_mask[0] |= BIT(i);
> +		als_adjust_channel_bit_mask(channels, index, st->als[i].size);
> +		++index;
>  
>  		dev_dbg(&pdev->dev, "als %x:%x\n", st->als[i].index,
>  			st->als[i].report_id);
>  	}
>  
> +	st->num_channels = index;
> +	/* Return success even if one usage id is present */
> +	if (index)
> +		ret = 0;
> +
>  	st->scale_precision = hid_sensor_format_scale(usage_id,
>  				&st->als[CHANNEL_SCAN_INDEX_INTENSITY],
>  				&st->scale_pre_decml, &st->scale_post_decml);
> @@ -294,15 +315,7 @@ static int hid_als_probe(struct platform_device *pdev)
>  		return ret;
>  	}
>  
> -	indio_dev->channels = devm_kmemdup(&pdev->dev, als_channels,
> -					   sizeof(als_channels), GFP_KERNEL);
> -	if (!indio_dev->channels) {
> -		dev_err(&pdev->dev, "failed to duplicate channels\n");
> -		return -ENOMEM;
> -	}
> -
>  	ret = als_parse_report(pdev, hsdev,
> -			       (struct iio_chan_spec *)indio_dev->channels,
>  			       hsdev->usage,
>  			       als_state);
>  	if (ret) {
> @@ -310,8 +323,15 @@ static int hid_als_probe(struct platform_device *pdev)
>  		return ret;
>  	}
>  
> -	indio_dev->num_channels =
> -				ARRAY_SIZE(als_channels);
> +	/* Add timestamp channel */
> +	als_state->channels[als_state->num_channels] = als_channels[CHANNEL_SCAN_INDEX_TIMESTAMP];
> +
> +	/* +1 for adding timestamp channel */
> +	indio_dev->num_channels = als_state->num_channels + 1;
> +
> +	indio_dev->channels = als_state->channels;
> +	indio_dev->available_scan_masks = als_scan_mask;
> +
>  	indio_dev->info = &als_info;
>  	indio_dev->name = name;
>  	indio_dev->modes = INDIO_DIRECT_MODE;

Re: [PATCH v4 4/4] iio: hid-sensor-als: Add light chromaticity support

[Jonathan Cameron]

On Sun,  4 Feb 2024 05:03:32 -0800
Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> wrote:

> From: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
> 
> On some platforms, ambient color sensors also support the x and y light
> colors, which represent the coordinates on the CIE 1931 chromaticity
> diagram. Add light chromaticity x and y.
> 
> Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Rest of series looks fine to me.

Jonathan

Re: [PATCH v4 1/4] iio: hid-sensor-als: Assign channels dynamically

[srinivas pandruvada]

Hi Jontahan,

On Sun, 2024-02-04 at 15:58 +0000, Jonathan Cameron wrote:
> On Sun,  4 Feb 2024 05:03:29 -0800
> Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> wrote:
> 
> > Instead of assuming that every channel defined statically by
> > als_channels[] is present, assign dynamically based on presence of
> > the
> > respective usage id in the descriptor. This will allow to register
> > ALS
> > with limited channel support. Append the timestamp as the last
> > channel.
> > 
> > Update available_scan_mask to specify all channels which are
> > present.
> > 
> > There is no intentional function changes done.
> > 
> > Signed-off-by: Srinivas Pandruvada
> > <srinivas.pandruvada@linux.intel.com>
> Hi Srinivas,
> 
> Logic looks fine, but not that global variable...
This will be a problem with multiple instances with different
combination. Although not seen in current devices, but this is
possible.
So will send an update.

Thanks,
Srinivas

> 

> > ---
> > v4:
> > Addressed comments from Jonthan:
> >         - Use available_scan_masks
> >         - timestamp location is fixed and left gaps in sample data
> > for absent channels
> >         - Use CHANNEL_SCAN_INDEX_MAX as limit to check presence of
> > usage ids, otherwise
> >           it will miss newer channels added in subsequent patches.
> > v3:
> > Addressed comments from Jonthan:
> >         - Remove channel allocation and move to iio_priv()
> >         - Parse all usage IDs in a single loop and continue
> >         for failure. This way the temperature and chromaticity
> >         will not need any special processing to parse usage ids.
> >         - Don't leave empty channel indexes
> > 
> > v2:
> > New change
> > 
> >  drivers/iio/light/hid-sensor-als.c | 52 +++++++++++++++++++++-----
> > ----
> >  1 file changed, 36 insertions(+), 16 deletions(-)
> > 
> > diff --git a/drivers/iio/light/hid-sensor-als.c
> > b/drivers/iio/light/hid-sensor-als.c
> > index b6c4bef2a7bb..d3b892c0e307 100644
> > --- a/drivers/iio/light/hid-sensor-als.c
> > +++ b/drivers/iio/light/hid-sensor-als.c
> > @@ -25,6 +25,7 @@ struct als_state {
> >         struct hid_sensor_hub_callbacks callbacks;
> >         struct hid_sensor_common common_attributes;
> >         struct hid_sensor_hub_attribute_info
> > als[CHANNEL_SCAN_INDEX_MAX];
> > +       struct iio_chan_spec channels[CHANNEL_SCAN_INDEX_MAX + 1];
> >         struct {
> >                 u32 illum[CHANNEL_SCAN_INDEX_MAX];
> >                 u64 timestamp __aligned(8);
> > @@ -33,9 +34,16 @@ struct als_state {
> >         int scale_post_decml;
> >         int scale_precision;
> >         int value_offset;
> > +       int num_channels;
> >         s64 timestamp;
> >  };
> >  
> > +/* The order of usage ids must match scan index starting from
> > CHANNEL_SCAN_INDEX_INTENSITY */
> > +static const u32 als_usage_ids[] = {
> > +       HID_USAGE_SENSOR_LIGHT_ILLUM,
> > +       HID_USAGE_SENSOR_LIGHT_ILLUM,
> > +};
> > +
> >  static const u32 als_sensitivity_addresses[] = {
> >         HID_USAGE_SENSOR_DATA_LIGHT,
> >         HID_USAGE_SENSOR_LIGHT_ILLUM,
> > @@ -68,6 +76,8 @@ static const struct iio_chan_spec als_channels[]
> > = {
> >         IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)
> >  };
> >  
> > +static unsigned long als_scan_mask[] = {0, 0};
> 
> Global? No. Could be multiple instances with different sensors
> supported.
> Needs to be embedded in the als_state structure so it is per
> instance.
> 
> > +
> >  /* Adjust channel real bits based on report descriptor */
> >  static void als_adjust_channel_bit_mask(struct iio_chan_spec
> > *channels,
> >                                         int channel, int size)
> > @@ -238,27 +248,38 @@ static int als_capture_sample(struct
> > hid_sensor_hub_device *hsdev,
> >  /* Parse report which is specific to an usage id*/
> >  static int als_parse_report(struct platform_device *pdev,
> >                                 struct hid_sensor_hub_device
> > *hsdev,
> > -                               struct iio_chan_spec *channels,
> >                                 unsigned usage_id,
> >                                 struct als_state *st)
> >  {
> > -       int ret;
> > +       struct iio_chan_spec *channels;
> > +       int ret, index = 0;
> >         int i;
> >  
> > -       for (i = 0; i <= CHANNEL_SCAN_INDEX_ILLUM; ++i) {
> > +       channels = st->channels;
> > +
> > +       for (i = 0; i < CHANNEL_SCAN_INDEX_MAX; ++i) {
> >                 ret = sensor_hub_input_get_attribute_info(hsdev,
> >                                                 HID_INPUT_REPORT,
> >                                                 usage_id,
> > -
> >                                                HID_USAGE_SENSOR_LIGH
> > T_ILLUM,
> > +                                               als_usage_ids[i],
> >                                                 &st->als[i]);
> >                 if (ret < 0)
> > -                       return ret;
> > -               als_adjust_channel_bit_mask(channels, i, st-
> > >als[i].size);
> > +                       continue;
> > +
> > +               channels[index] = als_channels[i];
> > +               als_scan_mask[0] |= BIT(i);
> > +               als_adjust_channel_bit_mask(channels, index, st-
> > >als[i].size);
> > +               ++index;
> >  
> >                 dev_dbg(&pdev->dev, "als %x:%x\n", st-
> > >als[i].index,
> >                         st->als[i].report_id);
> >         }
> >  
> > +       st->num_channels = index;
> > +       /* Return success even if one usage id is present */
> > +       if (index)
> > +               ret = 0;
> > +
> >         st->scale_precision = hid_sensor_format_scale(usage_id,
> >                                 &st-
> > >als[CHANNEL_SCAN_INDEX_INTENSITY],
> >                                 &st->scale_pre_decml, &st-
> > >scale_post_decml);
> > @@ -294,15 +315,7 @@ static int hid_als_probe(struct
> > platform_device *pdev)
> >                 return ret;
> >         }
> >  
> > -       indio_dev->channels = devm_kmemdup(&pdev->dev,
> > als_channels,
> > -                                          sizeof(als_channels),
> > GFP_KERNEL);
> > -       if (!indio_dev->channels) {
> > -               dev_err(&pdev->dev, "failed to duplicate
> > channels\n");
> > -               return -ENOMEM;
> > -       }
> > -
> >         ret = als_parse_report(pdev, hsdev,
> > -                              (struct iio_chan_spec *)indio_dev-
> > >channels,
> >                                hsdev->usage,
> >                                als_state);
> >         if (ret) {
> > @@ -310,8 +323,15 @@ static int hid_als_probe(struct
> > platform_device *pdev)
> >                 return ret;
> >         }
> >  
> > -       indio_dev->num_channels =
> > -                               ARRAY_SIZE(als_channels);
> > +       /* Add timestamp channel */
> > +       als_state->channels[als_state->num_channels] =
> > als_channels[CHANNEL_SCAN_INDEX_TIMESTAMP];
> > +
> > +       /* +1 for adding timestamp channel */
> > +       indio_dev->num_channels = als_state->num_channels + 1;
> > +
> > +       indio_dev->channels = als_state->channels;
> > +       indio_dev->available_scan_masks = als_scan_mask;
> > +
> >         indio_dev->info = &als_info;
> >         indio_dev->name = name;
> >         indio_dev->modes = INDIO_DIRECT_MODE;
>