diff mbox series

[v3,1/4] iio: hid-sensor-als: Assign channels dynamically

Message ID 20240109180007.3373784-2-srinivas.pandruvada@linux.intel.com (mailing list archive)
State Superseded
Headers show
Series Add support of color temperature and chromaticity | expand

Commit Message

srinivas pandruvada Jan. 9, 2024, 6 p.m. UTC
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.

When not all usage ids are present, the scan index is adjusted to
exclude unsupported channels.

There is no intentional function changes done.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
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 | 56 +++++++++++++++++++++---------
 1 file changed, 39 insertions(+), 17 deletions(-)

Comments

Jonathan Cameron Jan. 13, 2024, 4:03 p.m. UTC | #1
On Tue,  9 Jan 2024 10:00:04 -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.
> 
> When not all usage ids are present, the scan index is adjusted to
> exclude unsupported channels.
> 
> There is no intentional function changes done.
> 
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
> ---
> 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

There isn't really a problem if you did want to leave them.
There are a number of other devices that do leave gaps and userspace
code shouldn't mind that.  I don't mind them being more tightly packed
though so this is also fine.


I was just looking at the driver and noticed one other oddity.
In als_capture_sample, it always returns -EINVAL if the timestamp channel
is being queried.

> 
> v2:
> New change
> 
>  drivers/iio/light/hid-sensor-als.c | 56 +++++++++++++++++++++---------
>  1 file changed, 39 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/iio/light/hid-sensor-als.c b/drivers/iio/light/hid-sensor-als.c
> index 5cd27f04b45e..72a7c01c97f8 100644
> --- a/drivers/iio/light/hid-sensor-als.c
> +++ b/drivers/iio/light/hid-sensor-als.c
> @@ -25,17 +25,26 @@ 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];
> +		u32 scan_index[CHANNEL_SCAN_INDEX_MAX];
This looks unlikely to end up right with a varying number of channels.
I'm assuming the device always captures all available channels.
As such, if there are 2 channels the timestamp will end up at byte 8 onwards.
If there are 3 channels, byte 16 onwards etc.

Usually when we have a floating timestamp like this we just rely on expanding
the channel array to leave space and force the alignment of that to be suitable
for taking a timestamp.

I'm a bit confused not to see available_scan_mask being set though.
If userspace previously requested illumination only would the data
have ended up in the right location (offset 0?)

If you set available_scan_masks to specify all channels then the
IIO core will move things around for you. If it's not provided then
it is up to the driver to figure out where to put the data.

Otherwise the patch looks fine to me.

Jonathan



>  		u64 timestamp __aligned(8);
>  	} scan;
>  	int scale_pre_decml;
>  	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,
> @@ -216,11 +225,14 @@ static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
>  	struct als_state *als_state = iio_priv(indio_dev);
>  	int ret = -EINVAL;
>  	u32 sample_data = *(u32 *)raw_data;
> +	int scan_index;
>  
>  	switch (usage_id) {
>  	case HID_USAGE_SENSOR_LIGHT_ILLUM:
> -		als_state->scan.illum[CHANNEL_SCAN_INDEX_INTENSITY] = sample_data;
> -		als_state->scan.illum[CHANNEL_SCAN_INDEX_ILLUM] = sample_data;
> +		scan_index = als_state->scan.scan_index[CHANNEL_SCAN_INDEX_INTENSITY];
> +		als_state->scan.illum[scan_index] = sample_data;
> +		scan_index = als_state->scan.scan_index[CHANNEL_SCAN_INDEX_ILLUM];
> +		als_state->scan.illum[scan_index] = sample_data;
>  		ret = 0;
>  		break;
>  	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
> @@ -237,27 +249,39 @@ 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;
>  
> +	channels = st->channels;
> +
>  	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,
> +						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];
> +		st->scan.scan_index[i] = index;
> +
> +		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);
> @@ -293,15 +317,7 @@ 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) {
> @@ -309,8 +325,14 @@ 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];
> +	als_state->channels[als_state->num_channels].scan_index = als_state->num_channels;
> +
> +	/* +1 for adding timestamp channel */
> +	indio_dev->num_channels = als_state->num_channels + 1;
> +
> +	indio_dev->channels = als_state->channels;
>  	indio_dev->info = &als_info;
>  	indio_dev->name = name;
>  	indio_dev->modes = INDIO_DIRECT_MODE;
Basavaraj Natikar Jan. 25, 2024, 5:51 a.m. UTC | #2
Hi Srinivas,


On 1/9/2024 11:30 PM, Srinivas Pandruvada 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.
>
> When not all usage ids are present, the scan index is adjusted to
> exclude unsupported channels.
>
> There is no intentional function changes done.
>
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
> ---
> 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 | 56 +++++++++++++++++++++---------
>  1 file changed, 39 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/iio/light/hid-sensor-als.c b/drivers/iio/light/hid-sensor-als.c
> index 5cd27f04b45e..72a7c01c97f8 100644
> --- a/drivers/iio/light/hid-sensor-als.c
> +++ b/drivers/iio/light/hid-sensor-als.c
> @@ -25,17 +25,26 @@ 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];
> +		u32 scan_index[CHANNEL_SCAN_INDEX_MAX];
>  		u64 timestamp __aligned(8);
>  	} scan;
>  	int scale_pre_decml;
>  	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,
> @@ -216,11 +225,14 @@ static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
>  	struct als_state *als_state = iio_priv(indio_dev);
>  	int ret = -EINVAL;
>  	u32 sample_data = *(u32 *)raw_data;
> +	int scan_index;
>  
>  	switch (usage_id) {
>  	case HID_USAGE_SENSOR_LIGHT_ILLUM:
> -		als_state->scan.illum[CHANNEL_SCAN_INDEX_INTENSITY] = sample_data;
> -		als_state->scan.illum[CHANNEL_SCAN_INDEX_ILLUM] = sample_data;
> +		scan_index = als_state->scan.scan_index[CHANNEL_SCAN_INDEX_INTENSITY];
> +		als_state->scan.illum[scan_index] = sample_data;
> +		scan_index = als_state->scan.scan_index[CHANNEL_SCAN_INDEX_ILLUM];
> +		als_state->scan.illum[scan_index] = sample_data;

Could you please use original above change which works fine for some reason if
we use this change als_state->scan.scan_index we are getting garbage value. 

>  		ret = 0;
>  		break;
>  	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
> @@ -237,27 +249,39 @@ 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;
>  
> +	channels = st->channels;
> +
>  	for (i = 0; i <= CHANNEL_SCAN_INDEX_ILLUM; ++i) {

Could you please change CHANNEL_SCAN_INDEX_ILLUM to CHANNEL_SCAN_INDEX_MAX
which helps remaining 2 patches in the series. 

>  		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];
> +		st->scan.scan_index[i] = index;
> +
> +		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);
> @@ -293,15 +317,7 @@ 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) {
> @@ -309,8 +325,14 @@ 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];
> +	als_state->channels[als_state->num_channels].scan_index = als_state->num_channels;
> +
> +	/* +1 for adding timestamp channel */
> +	indio_dev->num_channels = als_state->num_channels + 1;
> +
> +	indio_dev->channels = als_state->channels;
>  	indio_dev->info = &als_info;
>  	indio_dev->name = name;
>  	indio_dev->modes = INDIO_DIRECT_MODE;
srinivas pandruvada Jan. 25, 2024, 6:01 a.m. UTC | #3
Hi Basavraj,

On 1/24/24 21:51, Basavaraj Natikar wrote:
> Hi Srinivas,
>
>
> On 1/9/2024 11:30 PM, Srinivas Pandruvada 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.
>>
>> When not all usage ids are present, the scan index is adjusted to
>> exclude unsupported channels.
>>
>> There is no intentional function changes done.
>>
>> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
>> ---
>> 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 | 56 +++++++++++++++++++++---------
>>   1 file changed, 39 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/iio/light/hid-sensor-als.c b/drivers/iio/light/hid-sensor-als.c
>> index 5cd27f04b45e..72a7c01c97f8 100644
>> --- a/drivers/iio/light/hid-sensor-als.c
>> +++ b/drivers/iio/light/hid-sensor-als.c
>> @@ -25,17 +25,26 @@ 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];
>> +		u32 scan_index[CHANNEL_SCAN_INDEX_MAX];
>>   		u64 timestamp __aligned(8);
>>   	} scan;
>>   	int scale_pre_decml;
>>   	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,
>> @@ -216,11 +225,14 @@ static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
>>   	struct als_state *als_state = iio_priv(indio_dev);
>>   	int ret = -EINVAL;
>>   	u32 sample_data = *(u32 *)raw_data;
>> +	int scan_index;
>>   
>>   	switch (usage_id) {
>>   	case HID_USAGE_SENSOR_LIGHT_ILLUM:
>> -		als_state->scan.illum[CHANNEL_SCAN_INDEX_INTENSITY] = sample_data;
>> -		als_state->scan.illum[CHANNEL_SCAN_INDEX_ILLUM] = sample_data;
>> +		scan_index = als_state->scan.scan_index[CHANNEL_SCAN_INDEX_INTENSITY];
>> +		als_state->scan.illum[scan_index] = sample_data;
>> +		scan_index = als_state->scan.scan_index[CHANNEL_SCAN_INDEX_ILLUM];
>> +		als_state->scan.illum[scan_index] = sample_data;
> Could you please use original above change which works fine for some reason if
> we use this change als_state->scan.scan_index we are getting garbage value.

I think this is because of the issue which you found later for this patch.


>>   		ret = 0;
>>   		break;
>>   	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
>> @@ -237,27 +249,39 @@ 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;
>>   
>> +	channels = st->channels;
>> +
>>   	for (i = 0; i <= CHANNEL_SCAN_INDEX_ILLUM; ++i) {
> Could you please change CHANNEL_SCAN_INDEX_ILLUM to CHANNEL_SCAN_INDEX_MAX
> which helps remaining 2 patches in the series.
>
Makes sense.


Thanks,

Srinivas


>>   		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];
>> +		st->scan.scan_index[i] = index;
>> +
>> +		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);
>> @@ -293,15 +317,7 @@ 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) {
>> @@ -309,8 +325,14 @@ 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];
>> +	als_state->channels[als_state->num_channels].scan_index = als_state->num_channels;
>> +
>> +	/* +1 for adding timestamp channel */
>> +	indio_dev->num_channels = als_state->num_channels + 1;
>> +
>> +	indio_dev->channels = als_state->channels;
>>   	indio_dev->info = &als_info;
>>   	indio_dev->name = name;
>>   	indio_dev->modes = INDIO_DIRECT_MODE;
srinivas pandruvada Feb. 4, 2024, 1:06 p.m. UTC | #4
Hi Jonathan,

On 1/13/24 08:03, Jonathan Cameron wrote:
> On Tue,  9 Jan 2024 10:00:04 -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.
>>
>> When not all usage ids are present, the scan index is adjusted to
>> exclude unsupported channels.
>>
>> There is no intentional function changes done.
>>
>> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
>> ---
>> 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
> There isn't really a problem if you did want to leave them.
> There are a number of other devices that do leave gaps and userspace
> code shouldn't mind that.  I don't mind them being more tightly packed
> though so this is also fine.
Submitted v4 leaving gaps.
>
>
> I was just looking at the driver and noticed one other oddity.
> In als_capture_sample, it always returns -EINVAL if the timestamp channel
> is being queried.

Correct. But hid-sensor-hub core ignores return value, so it doesn't 
cause any issue.

But I sent a separate patch to fix this.


>
>> v2:
>> New change
>>
>>   drivers/iio/light/hid-sensor-als.c | 56 +++++++++++++++++++++---------
>>   1 file changed, 39 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/iio/light/hid-sensor-als.c b/drivers/iio/light/hid-sensor-als.c
>> index 5cd27f04b45e..72a7c01c97f8 100644
>> --- a/drivers/iio/light/hid-sensor-als.c
>> +++ b/drivers/iio/light/hid-sensor-als.c
>> @@ -25,17 +25,26 @@ 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];
>> +		u32 scan_index[CHANNEL_SCAN_INDEX_MAX];
> This looks unlikely to end up right with a varying number of channels.
> I'm assuming the device always captures all available channels.
> As such, if there are 2 channels the timestamp will end up at byte 8 onwards.
> If there are 3 channels, byte 16 onwards etc.
>
> Usually when we have a floating timestamp like this we just rely on expanding
> the channel array to leave space and force the alignment of that to be suitable
> for taking a timestamp.
>
> I'm a bit confused not to see available_scan_mask being set though.
> If userspace previously requested illumination only would the data
> have ended up in the right location (offset 0?)
Add this.
> If you set available_scan_masks to specify all channels then the
> IIO core will move things around for you. If it's not provided then
> it is up to the driver to figure out where to put the data.
>
> Otherwise the patch looks fine to me.

Please check v4, if it solve the above issues.

Thanks,

Srinivas



> Jonathan
>
>
>
>>   		u64 timestamp __aligned(8);
>>   	} scan;
>>   	int scale_pre_decml;
>>   	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,
>> @@ -216,11 +225,14 @@ static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
>>   	struct als_state *als_state = iio_priv(indio_dev);
>>   	int ret = -EINVAL;
>>   	u32 sample_data = *(u32 *)raw_data;
>> +	int scan_index;
>>   
>>   	switch (usage_id) {
>>   	case HID_USAGE_SENSOR_LIGHT_ILLUM:
>> -		als_state->scan.illum[CHANNEL_SCAN_INDEX_INTENSITY] = sample_data;
>> -		als_state->scan.illum[CHANNEL_SCAN_INDEX_ILLUM] = sample_data;
>> +		scan_index = als_state->scan.scan_index[CHANNEL_SCAN_INDEX_INTENSITY];
>> +		als_state->scan.illum[scan_index] = sample_data;
>> +		scan_index = als_state->scan.scan_index[CHANNEL_SCAN_INDEX_ILLUM];
>> +		als_state->scan.illum[scan_index] = sample_data;
>>   		ret = 0;
>>   		break;
>>   	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
>> @@ -237,27 +249,39 @@ 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;
>>   
>> +	channels = st->channels;
>> +
>>   	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,
>> +						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];
>> +		st->scan.scan_index[i] = index;
>> +
>> +		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);
>> @@ -293,15 +317,7 @@ 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) {
>> @@ -309,8 +325,14 @@ 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];
>> +	als_state->channels[als_state->num_channels].scan_index = als_state->num_channels;
>> +
>> +	/* +1 for adding timestamp channel */
>> +	indio_dev->num_channels = als_state->num_channels + 1;
>> +
>> +	indio_dev->channels = als_state->channels;
>>   	indio_dev->info = &als_info;
>>   	indio_dev->name = name;
>>   	indio_dev->modes = INDIO_DIRECT_MODE;
diff mbox series

Patch

diff --git a/drivers/iio/light/hid-sensor-als.c b/drivers/iio/light/hid-sensor-als.c
index 5cd27f04b45e..72a7c01c97f8 100644
--- a/drivers/iio/light/hid-sensor-als.c
+++ b/drivers/iio/light/hid-sensor-als.c
@@ -25,17 +25,26 @@  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];
+		u32 scan_index[CHANNEL_SCAN_INDEX_MAX];
 		u64 timestamp __aligned(8);
 	} scan;
 	int scale_pre_decml;
 	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,
@@ -216,11 +225,14 @@  static int als_capture_sample(struct hid_sensor_hub_device *hsdev,
 	struct als_state *als_state = iio_priv(indio_dev);
 	int ret = -EINVAL;
 	u32 sample_data = *(u32 *)raw_data;
+	int scan_index;
 
 	switch (usage_id) {
 	case HID_USAGE_SENSOR_LIGHT_ILLUM:
-		als_state->scan.illum[CHANNEL_SCAN_INDEX_INTENSITY] = sample_data;
-		als_state->scan.illum[CHANNEL_SCAN_INDEX_ILLUM] = sample_data;
+		scan_index = als_state->scan.scan_index[CHANNEL_SCAN_INDEX_INTENSITY];
+		als_state->scan.illum[scan_index] = sample_data;
+		scan_index = als_state->scan.scan_index[CHANNEL_SCAN_INDEX_ILLUM];
+		als_state->scan.illum[scan_index] = sample_data;
 		ret = 0;
 		break;
 	case HID_USAGE_SENSOR_TIME_TIMESTAMP:
@@ -237,27 +249,39 @@  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;
 
+	channels = st->channels;
+
 	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,
+						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];
+		st->scan.scan_index[i] = index;
+
+		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);
@@ -293,15 +317,7 @@  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) {
@@ -309,8 +325,14 @@  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];
+	als_state->channels[als_state->num_channels].scan_index = als_state->num_channels;
+
+	/* +1 for adding timestamp channel */
+	indio_dev->num_channels = als_state->num_channels + 1;
+
+	indio_dev->channels = als_state->channels;
 	indio_dev->info = &als_info;
 	indio_dev->name = name;
 	indio_dev->modes = INDIO_DIRECT_MODE;