Re: [RFC PATCH 1/2] thermal: iio device for thermal sensor

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Sun, 2015-08-23 at 21:10 +0100, Jonathan Cameron wrote:
> On 18/08/15 00:52, Srinivas Pandruvada wrote:
> Hi Srinivas,
Hi Jonathan,
> 
> I'm not familiar enough with thermal to know how much sense the 
> support
> makes, so mostly my review will concern itself with just the IIO side 
> of
> things.
> 
> > The only method to read temperature of a thermal zone is by reading 
> > sysfs
> > entry "temp". This works well when kernel is primarily doing 
> > thermal
> > control and user mode tools/applications are reading temperature 
> > for
> > display or debug purposes. But when user mode is doing primary 
> > thermal
> > control using a "user space" governor, this model causes 
> > performance
> > issues and have limitations. For example Linux thermal daemon or 
> > Intel®
> > Dynamic Platform and Thermal Framework (DPTF) for Chromium/Chrome 
> > OS are
> > currently used as user space thermal controllers in several 
> > products.
> > We have platforms with 10+ thermal sensors and thermal conditions 
> > are not
> > an isolated cases, so it is important to manage thermal conditions 
> > without
> > significantly degrading user experience. So we need an efficient 
> > way to
> > read temperature and events, by
> > - Not using polling from user space
> > - Avoid sysfs string read for temperature and convert to decimal
> > - Push model, so that driver can push changes when some temperature
> > change event occurs, which needs attention
> > - Let user space registers for some thresholds without using some
> > passive trips
> > - Avoid string based kobject uevent notifications
> > - Able to use different external trigger (data ready indications) 
> > and push
> > temperature samples
> 
> The way you have done this is a little unusual...
> Whilst you register a trigger, it never fires.  You drive
> the buffer directly.
> 
> To do a true trigger (as an interrupt) from a functional call like 
> that seen
> here is a bit of a dance, but can be done if necessary.
> I'm not sure I'm keen on the trick pulled here to avoid it.
> 
I have these use cases. Not sure how best to handle
- Some thermal drivers have its own interrupts like a real trigger.
Those interrupts are registered in the drivers itself. For example:
http://lxr.free-electrons.com/source/drivers/thermal/intel_soc_dts_ther
mal.c line 446.
In such case data will be directly pushed to buffer from drivers via
thermal core interface.

- Some drivers data ready is from some external events for example a
indication from PMIC (Power management ICs). Becuase they are wired in
so many different ways and provide interrupts, this will pollute
drivers if each driver handles all cases. I rather use interrupt-
trigger to sample temperature.

- In some case drivers we need to sample on some external conditions
identified from user space and use sysfs trigger to push sample.
 
- If drivers don't have capability to interrupt, we still use push
interface to send temperature samples uses something like RTC trigger.


> What you can do is use the validate callback to restrict the trigger 
> you have
> here to driving only the buffer in this same driver.
> Then you can be sure that useing iio_trigger_poll_chained is fine.
> That can be done without the irq_work dance.  Other triggers (don't
> provide a validate callback in the other direction) should
> then also work fine and you won't need to replicate the read
> and push to buffers as currently.  The other triggers will just
> see a threaded irq with no 'top half' and work normally.
> 
> > 
> > There are some ways to achieve this using thermal sysfs 2.0, but 
> > still
> > doesn't meet all requirements and will introduce backward 
> > compatibility
> > issues. Other option is to enhance thermal sysfs by adding a sensor
> > abstractions and providing a dev interface for poll/select. But 
> > since
> > since Linux IIO already provides above capabilities, it is better 
> > we
> > reuse IIO temperature sensor device. This change proposes use of 
> > IIO
> > temperature sensor device for a thermal zone. Here IIO capabilities
> > of triggered buffer and events are utilized.
> > 
> > The iio device created during call to thermal_zone_device_register.
> > Samples are pushed to iio buffers when thermal_zone_device_update 
> > is
> > called from client drivers and user space governor is selected for 
> > the
> > thermal zone. Only two additional callbacks for client driver to 
> > get/set
> > thermal temperature thresholds.
> > 
> > Signed-off-by: Srinivas Pandruvada <
> > srinivas.pandruvada@xxxxxxxxxxxxxxx>
> 
> > ---
> >  drivers/thermal/Kconfig        |  11 ++
> >  drivers/thermal/Makefile       |   1 +
> >  drivers/thermal/thermal_core.c |   9 +-
> >  drivers/thermal/thermal_iio.c  | 333 
> > +++++++++++++++++++++++++++++++++++++++++
> >  drivers/thermal/user_space.c   |   1 +
> >  include/linux/thermal.h        |  46 ++++++
> >  6 files changed, 399 insertions(+), 2 deletions(-)
> >  create mode 100644 drivers/thermal/thermal_iio.c
> > 
> > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> > index 118938e..0ea9d8b 100644
> > --- a/drivers/thermal/Kconfig
> > +++ b/drivers/thermal/Kconfig
> > @@ -29,6 +29,17 @@ config THERMAL_HWMON
> >  	  Say 'Y' here if you want all thermal sensors to
> >  	  have hwmon sysfs interface too.
> >  
> > +config THERMAL_IIO
> > +	tristate "Thermal sensor from a zone as IIO device"
> > +	select IIO
> > +	select IIO_BUFFER
> > +	select IIO_TRIGGERED_BUFFER
> > +	help
> > +	  This will register thermal sensor in a zone as an IIO 
> > temperature
> > +	  sensor device.
> > +	  This will help user space thermal controllers to use IIO 
> > ABI to
> > +	  get events and buffered acces to temperature samples.
> > +
> >  config THERMAL_OF
> >  	bool
> >  	prompt "APIs to parse thermal data out of device tree"
> > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> > index 535dfee..4b42734 100644
> > --- a/drivers/thermal/Makefile
> > +++ b/drivers/thermal/Makefile
> > @@ -7,6 +7,7 @@ thermal_sys-y			+= 
> > thermal_core.o
> >  
> >  # interface to/from other layers providing sensors
> >  thermal_sys-$(CONFIG_THERMAL_HWMON)		+= 
> > thermal_hwmon.o
> > +thermal_sys-$(CONFIG_THERMAL_IIO)		+= thermal_iio.o
> >  thermal_sys-$(CONFIG_THERMAL_OF)		+= of-thermal.o
> >  
> >  # governors
> > diff --git a/drivers/thermal/thermal_core.c 
> > b/drivers/thermal/thermal_core.c
> > index 04659bf..483a4a1 100644
> > --- a/drivers/thermal/thermal_core.c
> > +++ b/drivers/thermal/thermal_core.c
> > @@ -1833,10 +1833,15 @@ struct thermal_zone_device 
> > *thermal_zone_device_register(const char *type,
> >  
> >  	mutex_unlock(&thermal_governor_lock);
> >  
> > +	if (thermal_iio_sensor_register(tz))
> > +		goto unregister;
> > +
> >  	if (!tz->tzp || !tz->tzp->no_hwmon) {
> >  		result = thermal_add_hwmon_sysfs(tz);
> > -		if (result)
> > +		if (result) {
> > +			thermal_iio_sensor_unregister(tz);
> >  			goto unregister;
> > +		}
> >  	}
> >  
> >  	mutex_lock(&thermal_list_lock);
> > @@ -1919,7 +1924,7 @@ void thermal_zone_device_unregister(struct 
> > thermal_zone_device *tz)
> >  	device_remove_file(&tz->device, &dev_attr_policy);
> >  	remove_trip_attrs(tz);
> >  	thermal_set_governor(tz, NULL);
> > -
> > +	thermal_iio_sensor_unregister(tz);
> >  	thermal_remove_hwmon_sysfs(tz);
> >  	release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
> >  	idr_destroy(&tz->idr);
> > diff --git a/drivers/thermal/thermal_iio.c 
> > b/drivers/thermal/thermal_iio.c
> > new file mode 100644
> > index 0000000..e36ad90
> > --- /dev/null
> > +++ b/drivers/thermal/thermal_iio.c
> > @@ -0,0 +1,333 @@
> > +/*
> > + * thermal iio interface driver
> > + * Copyright (c) 2015, Intel Corporation.
> > + *
> > + * This program is free software; you can redistribute it and/or 
> > modify it
> > + * under the terms and conditions of the GNU General Public 
> > License,
> > + * version 2, as published by the Free Software Foundation.
> > + *
> > + * This program is distributed in the hope it will be useful, but 
> > WITHOUT
> > + * ANY WARRANTY; without even the implied warranty of 
> > MERCHANTABILITY or
> > + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public 
> > License for
> > + * more details.
> > + */
> > +
> > +#include <linux/thermal.h>
> > +
> > +struct thermal_iio_data {
> > +	struct thermal_zone_device *tz;
> > +	struct iio_trigger *dready_trig;
> > +	s16 buffer[8];
> Why so big?  Far as I can tell you read one 32 bit number into it at 
> most?
> Also should also be a u32.  Actually I can't see why you need it
> in this structure at all.  
> 
I will fix this in RFC v2.

> > +	bool enable;
> > +	long temp_thres;
> > +	bool ev_enable_state;
> > +	struct mutex mutex;
> > +
> > +};
> > +
> > +static const struct iio_event_spec thermal_event = {
> > +		.type = IIO_EV_TYPE_THRESH,
> > +		.dir = IIO_EV_DIR_EITHER,
> > +		.mask_separate = BIT(IIO_EV_INFO_VALUE) |
> > +				 BIT(IIO_EV_INFO_ENABLE)
> > +};
> > +
> > +#define THERMAL_TEMP_CHANNELS {					
> > \
> > +	{								
> > \
> > +		.type = IIO_TEMP,					
> > \
> > +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	
> > 	\
> > +		.scan_index = 0,					
> > \
> > +		.scan_type = {					
> > 	\
> > +			.sign = 'u',				
> > 	\
> > +			.realbits = 32,				
> > \
> > +			.storagebits = 32,				
> > \
> > +			.shift = 0,				
> > 	\
> Don't bother specifying shift as that's the default (and intuitive 
> unlike
> scan_index above which should be specified for ease of reading).
> > +			.endianness = IIO_CPU,			
> > 	\
> > +		},
OK
> > 							\
> > +		.event_spec = &thermal_event,			
> > 	\
> > +		.num_event_specs = 1				
> > 	\
> > +	},								
> > \
> > +}
> > +
> > +static const struct iio_chan_spec thermal_iio_channels[] =
> > +							THERMAL_TE
> > MP_CHANNELS;
> > +
> > +static int thermal_iio_read_raw(struct iio_dev *indio_dev,
> > +				struct iio_chan_spec const *chan,
> > +				int *val, int *val2, long mask)
> > +{
> > +	struct thermal_iio_data *iio_data = iio_priv(indio_dev);
> > +	long temp;
> > +	int ret;
> > +
> > +	switch (mask) {
> > +	case IIO_CHAN_INFO_RAW:
> Any interactions between this read and a buffered one if that is 
> enabled?
> (don't know the limitations of the thermal stuff as to whether this
> is a direct read to hardware or not..)
This will provide on demand sample. The bufferred one will be pushed
when something like a threshold is reached.
Temperarture read can be as simple as reading a register. But sometimes
we need to do a combination of operation and then use interpolation.
> > +		ret = thermal_zone_get_temp(iio_data->tz, &temp);
> > +		if (ret)
> > +			return ret;
> > +		*val = (int) temp;
> > +		return IIO_VAL_INT;
> > +	default:
> > +		return -EINVAL;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> So this one is for when you are using other triggers...
> 
> Really don't like the two different paths depending on who is 
> triggering
> the read.
> 
> > +static irqreturn_t thermal_trigger_handler(int irq, void *p)
> > +{
> > +	struct iio_poll_func *pf = p;
> > +	struct iio_dev *indio_dev = pf->indio_dev;
> > +	struct thermal_iio_data *iio_data = iio_priv(indio_dev);
> > +	long temp;
> > +	int ret;
> > +
> > +	ret = thermal_zone_get_temp(iio_data->tz, &temp);
> > +	if (ret)
> > +		goto err_read;
> > +
> You have a channel spec saying it is unsigned...
Will fix this.
> > +	*(s32 *)iio_data->buffer = (s32)temp;
> > +	iio_push_to_buffers(indio_dev, iio_data->buffer);
> > +err_read:
> > +	iio_trigger_notify_done(indio_dev->trig);
> Blank line here.
OK
> > +	return IRQ_HANDLED;
> > +}
> > +
> > +static int thermal_data_rdy_trigger_set_state(struct iio_trigger 
> > *trig,
> > +					      bool state)
> > +{
> > +	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
> > +	struct thermal_iio_data *iio_data = iio_priv(indio_dev);
> > +
> > +	mutex_lock(&iio_data->mutex);
> > +	iio_data->enable = state;
> > +	mutex_unlock(&iio_data->mutex);
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct iio_trigger_ops thermal_trigger_ops = {
> > +	.set_trigger_state = thermal_data_rdy_trigger_set_state,
> > +	.owner = THIS_MODULE,
> > +};
> > +
> > +static int thermal_iio_read_event(struct iio_dev *indio_dev,
> > +				  const struct iio_chan_spec 
> > *chan,
> > +				  enum iio_event_type type,
> > +				  enum iio_event_direction dir,
> > +				  enum iio_event_info info,
> > +				  int *val, int *val2)
> > +{
> > +	struct thermal_iio_data *iio_data = iio_priv(indio_dev);
> > +	int ret;
> > +
> > +	mutex_lock(&iio_data->mutex);
> > +	*val2 = 0;
> > +	switch (info) {
> > +	case IIO_EV_INFO_VALUE:
> > +		*val = iio_data->temp_thres;
> > +		ret = IIO_VAL_INT;
> > +		break;
> > +	default:
> > +		ret = -EINVAL;
> > +		break;
> > +	}
> > +	mutex_unlock(&iio_data->mutex);
> > +
> > +	return ret;
> > +}
> > +
> > +static int thermal_iio_write_event(struct iio_dev *indio_dev,
> > +				   const struct iio_chan_spec 
> > *chan,
> > +				   enum iio_event_type type,
> > +				   enum iio_event_direction dir,
> > +				   enum iio_event_info info,
> > +				   int val, int val2)
> > +{
> > +	struct thermal_iio_data *iio_data = iio_priv(indio_dev);
> > +	int ret = 0;
> > +
> > +	mutex_lock(&iio_data->mutex);
> > +	if (iio_data->ev_enable_state) {
> Would it be risky to update the threshold live if the event is 
> enabled?
> Normally we try to do this if possible.
This will depend on the thermal client drivers on variety of platforms.
So just playing safe.
> 
> > +		ret = -EBUSY;
> > +		goto done_write_event;
> > +	}
> I'd insert a blank line here for readability.
OK
> > +	switch (info) {
> > +	case IIO_EV_INFO_VALUE:
> > +		iio_data->temp_thres = val;
> > +		break;
> > +	default:
> > +		ret = -EINVAL;
> > +		break;
> > +	}
> > +done_write_event:
> > +	mutex_unlock(&iio_data->mutex);
> > +
> > +	return ret;
> > +}
> > +
> > +static int thermal_iio_read_event_config(struct iio_dev 
> > *indio_dev,
> > +					 const struct 
> > iio_chan_spec *chan,
> > +					 enum iio_event_type type,
> > +					 enum iio_event_direction 
> > dir)
> > +{
> > +
> Random blank line here.
OK
> > +	struct thermal_iio_data *iio_data = iio_priv(indio_dev);
> > +	bool state;
> > +
> > +	mutex_lock(&iio_data->mutex);
> > +	state = iio_data->ev_enable_state;
> > +	mutex_unlock(&iio_data->mutex);
> > +
> > +	return state;
> > +}
> > +
> > +static int thermal_iio_write_event_config(struct iio_dev 
> > *indio_dev,
> > +					  const struct 
> > iio_chan_spec *chan,
> > +					  enum iio_event_type 
> > type,
> > +					  enum iio_event_direction 
> > dir,
> > +					  int state)
> > +{
> > +	struct thermal_iio_data *iio_data = iio_priv(indio_dev);
> > +	int ret = 0;
> > +
> > +	mutex_lock(&iio_data->mutex);
> What about both state and ev_enable_state being off?
> 
OK
> > +	if (state && iio_data->ev_enable_state)
> > +		goto done_write_event;
> > +
> > +	if (iio_data->tz->ops->set_threshold_temp)
> > +		ret = iio_data->tz->ops
> > ->set_threshold_temp(iio_data->tz, 0,
> > +							iio_data
> > ->temp_thres);
> > +	iio_data->ev_enable_state = state;
> > +
> > +done_write_event:
> > +	mutex_unlock(&iio_data->mutex);
> > +
> > +	return ret;
> > +}
> > +
> > +static const struct iio_info thermal_iio_info = {
> > +	.read_raw		= thermal_iio_read_raw,
> > +	.read_event_value	= thermal_iio_read_event,
> > +	.write_event_value	= thermal_iio_write_event,
> > +	.write_event_config	= 
> > thermal_iio_write_event_config,
> > +	.read_event_config	= thermal_iio_read_event_config,
> > +	.driver_module		= THIS_MODULE,
> > +};
> > +
> > +int thermal_iio_sensor_register(struct thermal_zone_device *tz)
> > +{
> > +	struct thermal_iio_data *iio_data;
> > +	int ret;
> > +
> Hmm.  We should probably provide support for embedding iio directly 
> in another
> structure at some point... Though handling the private data 
> allocation then
> gets complex.
> 
> Anyhow, this is fine for now.
> > +	tz->indio_dev = devm_iio_device_alloc(&tz->device, 
> > sizeof(*iio_data));
> > +	if (!tz->indio_dev)
> > +		return -ENOMEM;
> > +
> > +	iio_data = iio_priv(tz->indio_dev);
> > +	iio_data->tz = tz;
> > +	mutex_init(&iio_data->mutex);
> > +
> > +	tz->indio_dev->dev.parent = &tz->device;
> > +	tz->indio_dev->channels = thermal_iio_channels;
> > +	tz->indio_dev->num_channels = 
> > ARRAY_SIZE(thermal_iio_channels);
> > +	tz->indio_dev->name = tz->type;
> > +	tz->indio_dev->info = &thermal_iio_info;
> > +	tz->indio_dev->modes = INDIO_DIRECT_MODE;
> > +
> > +	iio_data->dready_trig = devm_iio_trigger_alloc(&tz
> > ->device, "%s-dev%d",
> > +						       tz->type,
> > +						       tz
> > ->indio_dev->id);
> > +	if (iio_data->dready_trig == NULL) {
> > +		dev_err(&tz->device, "Trigger Allocate Failed\n");
> > +		return -ENOMEM;
> > +	}
> > +
> > +	iio_data->dready_trig->dev.parent = &tz->device;
> > +	iio_data->dready_trig->ops = &thermal_trigger_ops;
> > +	iio_trigger_set_drvdata(iio_data->dready_trig, tz
> > ->indio_dev);
> > +	tz->indio_dev->trig = iio_data->dready_trig;
> > +	iio_trigger_get(tz->indio_dev->trig);
> > +	ret = iio_trigger_register(iio_data->dready_trig);
> > +	if (ret) {
> > +		dev_err(&tz->device, "Trigger Allocate Failed\n");
> > +		return ret;
> > +	}
> > +
> > +	ret = iio_triggered_buffer_setup(tz->indio_dev,
> Why store the time?  It's never used as the timestamp channel isn't 
> registered.
It was suggested to add time during LPC talk. So will need to add
timestamp channel.
> > +					 &iio_pollfunc_store_time,
> > +					 thermal_trigger_handler, 
> > NULL);
> > +	if (ret) {
> > +		dev_err(&tz->device, "failed to initialize trigger 
> > buffer\n");
> > +		goto err_unreg_trig;
> > +	}
> > +
> > +	ret = iio_device_register(tz->indio_dev);
> > +	if (ret < 0) {
> > +		dev_err(&tz->device, "unable to register iio 
> > device\n");
> > +		goto err_cleanup_trig;
> > +	}
> > +
> > +	return 0;
> > +
> > +err_cleanup_trig:
> > +	iio_triggered_buffer_cleanup(tz->indio_dev);
> > +err_unreg_trig:
> > +	iio_device_unregister(tz->indio_dev);
> > +
> > +	return ret;
> > +}
> > +
> > +int thermal_iio_sensor_unregister(struct thermal_zone_device *tz)
> > +{
> > +	struct thermal_iio_data *iio_data = iio_priv(tz
> > ->indio_dev);
> > +
> > +	iio_device_unregister(tz->indio_dev);
> > +	iio_triggered_buffer_cleanup(tz->indio_dev);
> > +	iio_trigger_unregister(iio_data->dready_trig);
> > +
> > +	return 0;
> > +}
> > +
> > +#define IIO_EVENT_CODE_THERMAL_THRES 
> > IIO_UNMOD_EVENT_CODE(IIO_TEMP, 0,\
> > +							 
> >  IIO_EV_TYPE_THRESH,\
> > +							 
> >  IIO_EV_DIR_EITHER)
> > +
> > +#define IIO_EVENT_CODE_TRIP_UPDATE IIO_UNMOD_EVENT_CODE(IIO_TEMP, 
> > 0,\
> > +							IIO_EV_TYP
> > E_CHANGE,\
> > +							IIO_EV_DIR
> > _NONE)
> 
> I'd like a justification of this particular one.  Normal use of
> the change type doesn't really apply here (counting steps etc)...
> (given one of the reviewers of this driver knows nothing about
> thermal (yet :)
> 
This is some case when driver wants to send event other than simple
threshold change. We have some other temperature change event not
because of threshold, for example error in temperature reporting
circuit. I want user space to wake up and read temperature and find out
the issue by error code returned and take action before.
> > +
> > +int thermal_iio_sensor_notify(struct thermal_zone_device *tz,
> > +			      enum thermal_zone_event_type event)
> > +{
> > +	struct thermal_iio_data *iio_data = iio_priv(tz
> > ->indio_dev);
> > +	long temp = 0;
> > +	int ret;
> > +
> > +	mutex_lock(&iio_data->mutex);
> > +	if (iio_data->ev_enable_state) {
> > +		if (event == THERMAL_TEMP_THRESHOLD)
> > +			iio_push_event(tz->indio_dev,
> > +				      
> >  IIO_EVENT_CODE_THERMAL_THRES,
> > +				       iio_get_time_ns());
> > +		else if (event == THERMAL_TRIP_UPDATE)
> > +			iio_push_event(tz->indio_dev,
> > +				       IIO_EVENT_CODE_TRIP_UPDATE,
> > +				       iio_get_time_ns());
> > +		else
> > +			dev_err(&tz->device, "invalid event\n");
> > +	}
> This enable needs a clearer name.
> > +	if (iio_data->enable) {
> > +		ret = thermal_zone_get_temp(iio_data->tz, &temp);
> > +		if (ret)
> > +			goto err_read;
> Why not read directly into the buffer?  Ah, the parameter is an 
> unsigned
> long so no guarantee it will be 32 bits (even if it currently will 
> be).
> That's tedious. Ah well!  Speaking of which, temp is signed. Doubt 
> you meant
> that.
> > +		*(u32 *)iio_data->buffer = (u32)temp;
> 
> So is there a real trigger here?  Doesn't look like to to me.
> Not sure what the reason for faking one is.  They aren't necessary
> where they don't make sense...
> 
> > +		iio_push_to_buffers(tz->indio_dev, iio_data
> > ->buffer);
> > +	}
> > +	mutex_unlock(&iio_data->mutex);
> > +
> > +	return 0;
> Drop through here and have only one exit point and unlock?  Obviously 
> set
> ret = 0 to ensure it's assigned.
ok
> > +err_read:
> > +	mutex_unlock(&iio_data->mutex);
> > +	return ret;
> > +}
> > diff --git a/drivers/thermal/user_space.c 
> > b/drivers/thermal/user_space.c
> > index 10adcdd..742adec 100644
> > --- a/drivers/thermal/user_space.c
> > +++ b/drivers/thermal/user_space.c
> > @@ -34,6 +34,7 @@
> >   */
> >  static int notify_user_space(struct thermal_zone_device *tz, int 
> > trip)
> >  {
> > +	thermal_iio_sensor_notify(tz, THERMAL_TEMP_THRESHOLD);
> >  	mutex_lock(&tz->lock);
> >  	kobject_uevent(&tz->device.kobj, KOBJ_CHANGE);
> >  	mutex_unlock(&tz->lock);
> > diff --git a/include/linux/thermal.h b/include/linux/thermal.h
> > index 037e9df..4c4c487 100644
> > --- a/include/linux/thermal.h
> > +++ b/include/linux/thermal.h
> > @@ -31,6 +31,16 @@
> >  #include <linux/workqueue.h>
> >  #include <uapi/linux/thermal.h>
> >  
> > +#if IS_ENABLED(CONFIG_THERMAL_IIO)
> > +#include <linux/iio/iio.h>
> > +#include <linux/iio/sysfs.h>
> > +#include <linux/iio/buffer.h>
> > +#include <linux/iio/trigger.h>
> > +#include <linux/iio/events.h>
> > +#include <linux/iio/trigger_consumer.h>
> > +#include <linux/iio/triggered_buffer.h>
> > +#endif
> > +
> >  #define THERMAL_TRIPS_NONE	-1
> >  #define THERMAL_MAX_TRIPS	12
> >  
> > @@ -111,6 +121,10 @@ struct thermal_zone_device_ops {
> >  	int (*set_emul_temp) (struct thermal_zone_device *, 
> > unsigned long);
> >  	int (*get_trend) (struct thermal_zone_device *, int,
> >  			  enum thermal_trend *);
> > +	int (*get_threshold_temp)(struct thermal_zone_device *, 
> > int,
> > +				  unsigned long *);
> > +	int (*set_threshold_temp)(struct thermal_zone_device *, 
> > int,
> > +				  unsigned long);
> >  	int (*notify) (struct thermal_zone_device *, int,
> >  		       enum thermal_trip_type);
> >  };
> > @@ -205,6 +219,9 @@ struct thermal_zone_device {
> >  	struct mutex lock;
> >  	struct list_head node;
> >  	struct delayed_work poll_queue;
> > +#ifdef CONFIG_THERMAL_IIO
> > +	struct iio_dev *indio_dev;
> > +#endif
> >  };
> >  
> >  /**
> > @@ -483,4 +500,33 @@ static inline int 
> > thermal_generate_netlink_event(struct thermal_zone_device *tz,
> >  }
> >  #endif
> >  
> > +enum thermal_zone_event_type {
> > +	THERMAL_TEMP_THRESHOLD,
> > +	THERMAL_TRIP_UPDATE,
> > +	THERMAL_EVENT_TYPE_MAX,
> > +};
> > +
> > +#if IS_ENABLED(CONFIG_THERMAL) && IS_ENABLED(CONFIG_THERMAL_IIO)
> > +int thermal_iio_sensor_register(struct thermal_zone_device *tz);
> > +int thermal_iio_sensor_unregister(struct thermal_zone_device *tz);
> > +int thermal_iio_sensor_notify(struct thermal_zone_device *tz,
> > +			      enum thermal_zone_event_type event);
> > +#else
> > +static int thermal_iio_sensor_register(struct thermal_zone_device 
> > *tz)
> > +{
> > +	return 0;
> > +}
> > +
> > +static int thermal_iio_sensor_unregister(struct 
> > thermal_zone_device *tz)
> > +{
> > +	return 0;
> > +}
> > +
> > +static int thermal_iio_sensor_notify(struct thermal_zone_device 
> > *tz
> > +				     enum thermal_zone_event_type 
> > event)
> > +{
> > +	return 0;
> > +}
> > +#endif
> > +
> >  #endif /* __THERMAL_H__ */
> > 
> 
Thanks,
Srinivas

> --
> To unsubscribe from this list: send the line "unsubscribe linux-pm" 
> in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Input]     [Linux Kernel]     [Linux SCSI]     [X.org]

  Powered by Linux