Re: [PATCH v3 3/4] thermal: core: genetlink support for events/cmd/sampling

[Zhang Rui]

On Fri, 2020-07-03 at 10:53 +0200, Daniel Lezcano wrote:
> Initially the thermal framework had a very simple notification
> mechanism to send generic netlink messages to the userspace.
> 
> The notification function was never called from anywhere and the
> corresponding dead code was removed. It was probably a first attempt
> to introduce the netlink notification.
> 
> At LPC2018, the presentation "Linux thermal: User kernel interface",
> proposed to create the notifications to the userspace via a kfifo.
> 
> The advantage of the kfifo is the performance. It is usually used
> from
> a 1:1 communication channel where a driver captures data and sends it
> as fast as possible to a userspace process.
> 
> The drawback is that only one process uses the notification channel
> exclusively, thus no other process is allowed to use the channel to
> get temperature or notifications.
> 
> This patch defines a generic netlink API to discover the current
> thermal setup and adds event notifications as well as temperature
> sampling. As any genetlink protocol, it can evolve and the versioning
> allows to keep the backward compatibility.
> 
> In order to prevent the user from getting flooded with data on a
> single channel, there are two multicast channels, one for the
> temperature sampling when the thermal zone is updated and another one
> for the events, so the user can get the events only without the
> thermal zone temperature sampling.
> 
> Also, a list of commands to discover the thermal setup is added and
> can be extended when needed.
> 
> Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
> ---
>   v3:
>       - Fixed changelog from Amit Kucheria suggestions
>       - Prefixed fields in the parameter structure (trip_*, cdev_*)
>       - Fixed leading whitespaces errors
>       - Replaced id by trip_id
>       - s/THERMAL_GENL_CMD_TZ_GET/THERMAL_GENL_CMD_TZ_GET_ID/
>       - Added the cdev max state in the cdev change event
>       - Removed min state
>       - Fixed checkpatch warnings
> ---
> ---
>  drivers/thermal/Makefile          |   2 +-
>  drivers/thermal/thermal_core.h    |  18 +
>  drivers/thermal/thermal_netlink.c | 650
> ++++++++++++++++++++++++++++++
>  include/linux/thermal.h           |  17 -
>  include/uapi/linux/thermal.h      |  90 ++++-
>  5 files changed, 742 insertions(+), 35 deletions(-)
>  create mode 100644 drivers/thermal/thermal_netlink.c
> 
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index 0c8b84a09b9a..1bbf0805fb04 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -5,7 +5,7 @@
>  
>  obj-$(CONFIG_THERMAL)		+= thermal_sys.o
>  thermal_sys-y			+= thermal_core.o
> thermal_sysfs.o \
> -					thermal_helpers.o
> +					thermal_helpers.o
> thermal_netlink.o
>  
>  # interface to/from other layers providing sensors
>  thermal_sys-$(CONFIG_THERMAL_HWMON)		+= thermal_hwmon.o
> diff --git a/drivers/thermal/thermal_core.h
> b/drivers/thermal/thermal_core.h
> index 4f8389efaa62..12bca87fb709 100644
> --- a/drivers/thermal/thermal_core.h
> +++ b/drivers/thermal/thermal_core.h
> @@ -52,6 +52,24 @@ int for_each_thermal_governor(int (*cb)(struct
> thermal_governor *, void *),
>  
>  struct thermal_zone_device *thermal_zone_get_by_id(int id);
>  
> +/* Netlink notification function */
> +int thermal_notify_tz_create(int tz_id, const char *name);
> +int thermal_notify_tz_delete(int tz_id);
> +int thermal_notify_tz_enable(int tz_id);
> +int thermal_notify_tz_disable(int tz_id);
> +int thermal_notify_tz_trip_down(int tz_id, int id);
> +int thermal_notify_tz_trip_up(int tz_id, int id);
> +int thermal_notify_tz_trip_delete(int tz_id, int id);
> +int thermal_notify_tz_trip_add(int tz_id, int id, int type,
> +			       int temp, int hyst);
> +int thermal_notify_tz_trip_change(int tz_id, int id, int type,
> +				  int temp, int hyst);
> +int thermal_notify_cdev_update(int cdev_id, int state);
> +int thermal_notify_cdev_add(int cdev_id, const char *name, int
> max_state);
> +int thermal_notify_cdev_delete(int cdev_id);
> +int thermal_notify_tz_gov_change(int tz_id, const char *name);
> +int thermal_genl_sampling_temp(int id, int temp);
> +
>  struct thermal_attr {
>  	struct device_attribute attr;
>  	char name[THERMAL_NAME_LENGTH];
> diff --git a/drivers/thermal/thermal_netlink.c
> b/drivers/thermal/thermal_netlink.c
> new file mode 100644
> index 000000000000..d3c48bbcd269
> --- /dev/null
> +++ b/drivers/thermal/thermal_netlink.c
> @@ -0,0 +1,650 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright 2020 Linaro Limited
> + *
> + * Author: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
> + *
> + * Generic netlink for thermal management framework
> + */
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <net/genetlink.h>
> +#include <uapi/linux/thermal.h>
> +
> +#include "thermal_core.h"
> +
> +static const struct genl_multicast_group thermal_genl_mcgrps[] = {
> +	{ .name = THERMAL_GENL_SAMPLING_GROUP_NAME, },
> +	{ .name = THERMAL_GENL_EVENT_GROUP_NAME,  },
> +};
> +
> +static const struct nla_policy
> thermal_genl_policy[THERMAL_GENL_ATTR_MAX + 1] = {
> +	/* Thermal zone */
> +	[THERMAL_GENL_ATTR_TZ]			= { .type =
> NLA_NESTED },
> +	[THERMAL_GENL_ATTR_TZ_ID]		= { .type = NLA_U32 },
> +	[THERMAL_GENL_ATTR_TZ_TEMP]		= { .type = NLA_U32
> },
> +	[THERMAL_GENL_ATTR_TZ_TRIP]		= { .type =
> NLA_NESTED },
> +	[THERMAL_GENL_ATTR_TZ_TRIP_ID]		= { .type = NLA_U32
> },
> +	[THERMAL_GENL_ATTR_TZ_TRIP_TEMP]	= { .type = NLA_U32 },
> +	[THERMAL_GENL_ATTR_TZ_TRIP_TYPE]	= { .type = NLA_U32 },
> +	[THERMAL_GENL_ATTR_TZ_TRIP_HYST]	= { .type = NLA_U32 },
> +	[THERMAL_GENL_ATTR_TZ_MODE]		= { .type = NLA_U32
> },
> +	[THERMAL_GENL_ATTR_TZ_CDEV_WEIGHT]	= { .type = NLA_U32
> },
> +	[THERMAL_GENL_ATTR_TZ_NAME]		= { .type =
> NLA_STRING,
> +						    .len =
> THERMAL_NAME_LENGTH },
> +	/* Governor(s) */
> +	[THERMAL_GENL_ATTR_TZ_GOV]		= { .type =
> NLA_NESTED },
> +	[THERMAL_GENL_ATTR_TZ_GOV_NAME]		= { .type =
> NLA_STRING,
> +						    .len =
> THERMAL_NAME_LENGTH },
> +	/* Cooling devices */
> +	[THERMAL_GENL_ATTR_CDEV]		= { .type = NLA_NESTED },
> +	[THERMAL_GENL_ATTR_CDEV_ID]		= { .type = NLA_U32
> },
> +	[THERMAL_GENL_ATTR_CDEV_CUR_STATE]	= { .type = NLA_U32
> },
> +	[THERMAL_GENL_ATTR_CDEV_MAX_STATE]	= { .type = NLA_U32
> },
> +	[THERMAL_GENL_ATTR_CDEV_NAME]		= { .type =
> NLA_STRING,
> +						    .len =
> THERMAL_NAME_LENGTH },
> +};
> +
> +struct param {
> +	struct nlattr **attrs;
> +	struct sk_buff *msg;
> +	const char *name;
> +	int tz_id;
> +	int cdev_id;
> +	int trip_id;
> +	int trip_temp;
> +	int trip_type;
> +	int trip_hyst;
> +	int temp;
> +	int cdev_state;
> +	int cdev_max_state;
> +};
> +
> +typedef int (*cb_t)(struct param *);
> +
> +static struct genl_family thermal_gnl_family;
> +
> +/************************** Sampling encoding
> *******************************/
> +
> +int thermal_genl_sampling_temp(int id, int temp)
> +{
> +	struct sk_buff *skb;
> +	void *hdr;
> +
> +	skb = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
> +	if (!skb)
> +		return -ENOMEM;
> +
> +	hdr = genlmsg_put(skb, 0, 0, &thermal_gnl_family, 0,
> +			  THERMAL_GENL_SAMPLING_TEMP);
> +	if (!hdr)
> +		return -EMSGSIZE;
> +
> +	if (nla_put_u32(skb, THERMAL_GENL_ATTR_TZ_ID, id))
> +		goto out_cancel;
> +
> +	if (nla_put_u32(skb, THERMAL_GENL_ATTR_TZ_TEMP, temp))
> +		goto out_cancel;
> +
> +	genlmsg_end(skb, hdr);
> +
> +	genlmsg_multicast(&thermal_gnl_family, skb, 0, 0, GFP_KERNEL);
> +
> +	return 0;
> +out_cancel:
> +	genlmsg_cancel(skb, hdr);
> +	nlmsg_free(skb);
> +
> +	return -EMSGSIZE;
> +}
> +
> +/**************************** Event encoding
> *********************************/
> +
> +static int thermal_genl_event_tz_create(struct param *p)
> +{
> +	if (nla_put_u32(p->msg, THERMAL_GENL_ATTR_TZ_ID, p->tz_id) ||
> +	    nla_put_string(p->msg, THERMAL_GENL_ATTR_TZ_NAME, p->name))
> +		return -EMSGSIZE;
> +
> +	return 0;
> +}
> +
> +static int thermal_genl_event_tz(struct param *p)
> +{
> +	if (nla_put_u32(p->msg, THERMAL_GENL_ATTR_TZ_ID, p->tz_id))
> +		return -EMSGSIZE;
> +
> +	return 0;
> +}
> +
> +static int thermal_genl_event_tz_trip_up(struct param *p)
> +{
> +	if (nla_put_u32(p->msg, THERMAL_GENL_ATTR_TZ_ID, p->tz_id) ||
> +	    nla_put_u32(p->msg, THERMAL_GENL_ATTR_TZ_TRIP_ID, p-
> >trip_id))
> +		return -EMSGSIZE;
> +
> +	return 0;
> +}
> +
> +static int thermal_genl_event_tz_trip_add(struct param *p)
> +{
> +	if (nla_put_u32(p->msg, THERMAL_GENL_ATTR_TZ_ID, p->tz_id) ||
> +	    nla_put_u32(p->msg, THERMAL_GENL_ATTR_TZ_TRIP_ID, p-
> >trip_id) ||
> +	    nla_put_u32(p->msg, THERMAL_GENL_ATTR_TZ_TRIP_TYPE, p-
> >trip_type) ||
> +	    nla_put_u32(p->msg, THERMAL_GENL_ATTR_TZ_TRIP_TEMP, p-
> >trip_temp) ||
> +	    nla_put_u32(p->msg, THERMAL_GENL_ATTR_TZ_TRIP_HYST, p-
> >trip_hyst))
> +		return -EMSGSIZE;
> +
> +	return 0;
> +}
> +
> +static int thermal_genl_event_tz_trip_delete(struct param *p)
> +{
> +	if (nla_put_u32(p->msg, THERMAL_GENL_ATTR_TZ_ID, p->tz_id) ||
> +	    nla_put_u32(p->msg, THERMAL_GENL_ATTR_TZ_TRIP_ID, p-
> >trip_id))
> +		return -EMSGSIZE;
> +
> +	return 0;
> +}
> +
> +static int thermal_genl_event_cdev_add(struct param *p)
> +{
> +	if (nla_put_string(p->msg, THERMAL_GENL_ATTR_CDEV_NAME,
> +			   p->name) ||
> +	    nla_put_u32(p->msg, THERMAL_GENL_ATTR_CDEV_ID,
> +			p->cdev_id) ||
> +	    nla_put_u32(p->msg, THERMAL_GENL_ATTR_CDEV_MAX_STATE,
> +			p->cdev_max_state))
> +		return -EMSGSIZE;
> +
> +	return 0;
> +}
> +
> +static int thermal_genl_event_cdev_delete(struct param *p)
> +{
> +	if (nla_put_u32(p->msg, THERMAL_GENL_ATTR_CDEV_ID, p->cdev_id))
> +		return -EMSGSIZE;
> +
> +	return 0;
> +}
> +
> +static int thermal_genl_event_cdev_update(struct param *p)
> +{
> +	if (nla_put_u32(p->msg, THERMAL_GENL_ATTR_CDEV_ID,
> +			p->cdev_id) ||
> +	    nla_put_u32(p->msg, THERMAL_GENL_ATTR_CDEV_CUR_STATE,
> +			p->cdev_state) ||
> +	    nla_put_u32(p->msg, THERMAL_GENL_ATTR_CDEV_MAX_STATE,
> +			p->cdev_max_state))
> +		return -EMSGSIZE;
> +
> +	return 0;
> +}

> +int thermal_notify_cdev_update(int cdev_id, int cdev_state)
> > +{
> > +	struct param p = { .cdev_id = cdev_id, .cdev_state = cdev_state
> > };
> 

.cdev_max_state is not set here.
I think we need to add a second parameter for cdev_max_state when
invoking thermal_nofify_cdev_update().

thanks,
rui


> +static int thermal_genl_event_gov_change(struct param *p)
> +{
> +	if (nla_put_u32(p->msg, THERMAL_GENL_ATTR_TZ_ID, p->tz_id) ||
> +	    nla_put_string(p->msg, THERMAL_GENL_ATTR_GOV_NAME, p-
> >name))
> +		return -EMSGSIZE;
> +
> +	return 0;
> +}
> +
> +int thermal_genl_event_tz_delete(struct param *p)
> +	__attribute__((alias("thermal_genl_event_tz")));
> +
> +int thermal_genl_event_tz_enable(struct param *p)
> +	__attribute__((alias("thermal_genl_event_tz")));
> +
> +int thermal_genl_event_tz_disable(struct param *p)
> +	__attribute__((alias("thermal_genl_event_tz")));
> +
> +int thermal_genl_event_tz_trip_down(struct param *p)
> +	__attribute__((alias("thermal_genl_event_tz_trip_up")));
> +
> +int thermal_genl_event_tz_trip_change(struct param *p)
> +	__attribute__((alias("thermal_genl_event_tz_trip_add")));
> +
> +static cb_t event_cb[] = {
> +	[THERMAL_GENL_EVENT_TZ_CREATE]		=
> thermal_genl_event_tz_create,
> +	[THERMAL_GENL_EVENT_TZ_DELETE]		=
> thermal_genl_event_tz_delete,
> +	[THERMAL_GENL_EVENT_TZ_ENABLE]		=
> thermal_genl_event_tz_enable,
> +	[THERMAL_GENL_EVENT_TZ_DISABLE]		=
> thermal_genl_event_tz_disable,
> +	[THERMAL_GENL_EVENT_TZ_TRIP_UP]		=
> thermal_genl_event_tz_trip_up,
> +	[THERMAL_GENL_EVENT_TZ_TRIP_DOWN]	=
> thermal_genl_event_tz_trip_down,
> +	[THERMAL_GENL_EVENT_TZ_TRIP_CHANGE]	=
> thermal_genl_event_tz_trip_change,
> +	[THERMAL_GENL_EVENT_TZ_TRIP_ADD]	=
> thermal_genl_event_tz_trip_add,
> +	[THERMAL_GENL_EVENT_TZ_TRIP_DELETE]	=
> thermal_genl_event_tz_trip_delete,
> +	[THERMAL_GENL_EVENT_CDEV_ADD]		=
> thermal_genl_event_cdev_add,
> +	[THERMAL_GENL_EVENT_CDEV_DELETE]	=
> thermal_genl_event_cdev_delete,
> +	[THERMAL_GENL_EVENT_CDEV_UPDATE]	=
> thermal_genl_event_cdev_update,
> +	[THERMAL_GENL_EVENT_TZ_GOV_CHANGE]	=
> thermal_genl_event_gov_change,
> +};
> +
> +/*
> + * Generic netlink event encoding
> + */
> +static int thermal_genl_send_event(enum thermal_genl_event event,
> +				   struct param *p)
> +{
> +	struct sk_buff *msg;
> +	int ret = -EMSGSIZE;
> +	void *hdr;
> +
> +	msg = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
> +	if (!msg)
> +		return -ENOMEM;
> +	p->msg = msg;
> +
> +	hdr = genlmsg_put(msg, 0, 0, &thermal_gnl_family, 0, event);
> +	if (!hdr)
> +		goto out_free_msg;
> +
> +	ret = event_cb[event](p);
> +	if (ret)
> +		goto out_cancel_msg;
> +
> +	genlmsg_end(msg, hdr);
> +
> +	genlmsg_multicast(&thermal_gnl_family, msg, 0, 1, GFP_KERNEL);
> +
> +	return 0;
> +
> +out_cancel_msg:
> +	genlmsg_cancel(msg, hdr);
> +out_free_msg:
> +	nlmsg_free(msg);
> +
> +	return ret;
> +}
> +
> +int thermal_notify_tz_create(int tz_id, const char *name)
> +{
> +	struct param p = { .tz_id = tz_id, .name = name };
> +
> +	return thermal_genl_send_event(THERMAL_GENL_EVENT_TZ_CREATE,
> &p);
> +}
> +
> +int thermal_notify_tz_delete(int tz_id)
> +{
> +	struct param p = { .tz_id = tz_id };
> +
> +	return thermal_genl_send_event(THERMAL_GENL_EVENT_TZ_DELETE,
> &p);
> +}
> +
> +int thermal_notify_tz_enable(int tz_id)
> +{
> +	struct param p = { .tz_id = tz_id };
> +
> +	return thermal_genl_send_event(THERMAL_GENL_EVENT_TZ_ENABLE,
> &p);
> +}
> +
> +int thermal_notify_tz_disable(int tz_id)
> +{
> +	struct param p = { .tz_id = tz_id };
> +
> +	return thermal_genl_send_event(THERMAL_GENL_EVENT_TZ_DISABLE,
> &p);
> +}
> +
> +int thermal_notify_tz_trip_down(int tz_id, int trip_id)
> +{
> +	struct param p = { .tz_id = tz_id, .trip_id = trip_id };
> +
> +	return thermal_genl_send_event(THERMAL_GENL_EVENT_TZ_TRIP_DOWN,
> &p);
> +}
> +
> +int thermal_notify_tz_trip_up(int tz_id, int trip_id)
> +{
> +	struct param p = { .tz_id = tz_id, .trip_id = trip_id };
> +
> +	return thermal_genl_send_event(THERMAL_GENL_EVENT_TZ_TRIP_UP,
> &p);
> +}
> +
> +int thermal_notify_tz_trip_add(int tz_id, int trip_id, int
> trip_type,
> +			       int trip_temp, int trip_hyst)
> +{
> +	struct param p = { .tz_id = tz_id, .trip_id = trip_id,
> +			   .trip_type = trip_type, .trip_temp =
> trip_temp,
> +			   .trip_hyst = trip_hyst };
> +
> +	return thermal_genl_send_event(THERMAL_GENL_EVENT_TZ_TRIP_ADD,
> &p);
> +}
> +
> +int thermal_notify_tz_trip_delete(int tz_id, int trip_id)
> +{
> +	struct param p = { .tz_id = tz_id, .trip_id = trip_id };
> +
> +	return
> thermal_genl_send_event(THERMAL_GENL_EVENT_TZ_TRIP_DELETE, &p);
> +}
> +
> +int thermal_notify_tz_trip_change(int tz_id, int trip_id, int
> trip_type,
> +				  int trip_temp, int trip_hyst)
> +{
> +	struct param p = { .tz_id = tz_id, .trip_id = trip_id,
> +			   .trip_type = trip_type, .trip_temp =
> trip_temp,
> +			   .trip_hyst = trip_hyst };
> +
> +	return
> thermal_genl_send_event(THERMAL_GENL_EVENT_TZ_TRIP_CHANGE, &p);
> +}
> +
> +int thermal_notify_cdev_update(int cdev_id, int cdev_state)
> +{
> +	struct param p = { .cdev_id = cdev_id, .cdev_state = cdev_state
> };

> +
> +	return thermal_genl_send_event(THERMAL_GENL_EVENT_CDEV_UPDATE,
> &p);
> +}
> +
> +int thermal_notify_cdev_add(int cdev_id, const char *name, int
> cdev_max_state)
> +{
> +	struct param p = { .cdev_id = cdev_id, .name = name,
> +			   .cdev_max_state = cdev_max_state };
> +
> +	return thermal_genl_send_event(THERMAL_GENL_EVENT_CDEV_ADD,
> &p);
> +}
> +
> +int thermal_notify_cdev_delete(int cdev_id)
> +{
> +	struct param p = { .cdev_id = cdev_id };
> +
> +	return thermal_genl_send_event(THERMAL_GENL_EVENT_CDEV_DELETE,
> &p);
> +}
> +
> +int thermal_notify_tz_gov_change(int tz_id, const char *name)
> +{
> +	struct param p = { .tz_id = tz_id, .name = name };
> +
> +	return
> thermal_genl_send_event(THERMAL_GENL_EVENT_TZ_GOV_CHANGE, &p);
> +}
> +
> +/*************************** Command encoding
> ********************************/
> +
> +static int __thermal_genl_cmd_tz_get_id(struct thermal_zone_device
> *tz,
> +					void *data)
> +{
> +	struct sk_buff *msg = data;
> +
> +	if (nla_put_u32(msg, THERMAL_GENL_ATTR_TZ_ID, tz->id) ||
> +	    nla_put_string(msg, THERMAL_GENL_ATTR_TZ_NAME, tz->type))
> +		return -EMSGSIZE;
> +
> +	return 0;
> +}
> +
> +static int thermal_genl_cmd_tz_get_id(struct param *p)
> +{
> +	struct sk_buff *msg = p->msg;
> +	struct nlattr *start_tz;
> +	int ret;
> +
> +	start_tz = nla_nest_start(msg, THERMAL_GENL_ATTR_TZ);
> +	if (!start_tz)
> +		return -EMSGSIZE;
> +
> +	ret = for_each_thermal_zone(__thermal_genl_cmd_tz_get_id, msg);
> +	if (ret)
> +		goto out_cancel_nest;
> +
> +	nla_nest_end(msg, start_tz);
> +
> +	return 0;
> +
> +out_cancel_nest:
> +	nla_nest_cancel(msg, start_tz);
> +
> +	return ret;
> +}
> +
> +static int thermal_genl_cmd_tz_get_trip(struct param *p)
> +{
> +	struct sk_buff *msg = p->msg;
> +	struct thermal_zone_device *tz;
> +	struct nlattr *start_trip;
> +	int i, id;
> +
> +	if (!p->attrs[THERMAL_GENL_ATTR_TZ_ID])
> +		return -EINVAL;
> +
> +	id = nla_get_u32(p->attrs[THERMAL_GENL_ATTR_TZ_ID]);
> +
> +	tz = thermal_zone_get_by_id(id);
> +	if (!tz)
> +		return -EINVAL;
> +
> +	start_trip = nla_nest_start(msg, THERMAL_GENL_ATTR_TZ_TRIP);
> +	if (!start_trip)
> +		return -EMSGSIZE;
> +
> +	mutex_lock(&tz->lock);
> +
> +	for (i = 0; i < tz->trips; i++) {
> +
> +		enum thermal_trip_type type;
> +		int temp, hyst;
> +
> +		tz->ops->get_trip_type(tz, i, &type);
> +		tz->ops->get_trip_temp(tz, i, &temp);
> +		tz->ops->get_trip_hyst(tz, i, &hyst);
> +
> +		if (nla_put_u32(msg, THERMAL_GENL_ATTR_TZ_TRIP_ID, i)
> ||
> +		    nla_put_u32(msg, THERMAL_GENL_ATTR_TZ_TRIP_TYPE,
> type) ||
> +		    nla_put_u32(msg, THERMAL_GENL_ATTR_TZ_TRIP_TEMP,
> temp) ||
> +		    nla_put_u32(msg, THERMAL_GENL_ATTR_TZ_TRIP_HYST,
> hyst))
> +			goto out_cancel_nest;
> +	}
> +
> +	mutex_unlock(&tz->lock);
> +
> +	nla_nest_end(msg, start_trip);
> +
> +	return 0;
> +
> +out_cancel_nest:
> +	mutex_unlock(&tz->lock);
> +
> +	return -EMSGSIZE;
> +}
> +
> +static int thermal_genl_cmd_tz_get_temp(struct param *p)
> +{
> +	struct sk_buff *msg = p->msg;
> +	struct thermal_zone_device *tz;
> +	int temp, ret, id;
> +
> +	if (!p->attrs[THERMAL_GENL_ATTR_TZ_ID])
> +		return -EINVAL;
> +
> +	id = nla_get_u32(p->attrs[THERMAL_GENL_ATTR_TZ_ID]);
> +
> +	tz = thermal_zone_get_by_id(id);
> +	if (!tz)
> +		return -EINVAL;
> +
> +	ret = thermal_zone_get_temp(tz, &temp);
> +	if (ret)
> +		return ret;
> +
> +	if (nla_put_u32(msg, THERMAL_GENL_ATTR_TZ_ID, id) ||
> +	    nla_put_u32(msg, THERMAL_GENL_ATTR_TZ_TEMP, temp))
> +		return -EMSGSIZE;
> +
> +	return 0;
> +}
> +
> +static int thermal_genl_cmd_tz_get_gov(struct param *p)
> +{
> +	struct sk_buff *msg = p->msg;
> +	struct thermal_zone_device *tz;
> +	int id, ret = 0;
> +
> +	if (!p->attrs[THERMAL_GENL_ATTR_TZ_ID])
> +		return -EINVAL;
> +
> +	id = nla_get_u32(p->attrs[THERMAL_GENL_ATTR_TZ_ID]);
> +
> +	tz = thermal_zone_get_by_id(id);
> +	if (!tz)
> +		return -EINVAL;
> +
> +	mutex_lock(&tz->lock);
> +
> +	if (nla_put_u32(msg, THERMAL_GENL_ATTR_TZ_ID, id) ||
> +	    nla_put_string(msg, THERMAL_GENL_ATTR_TZ_GOV_NAME,
> +			   tz->governor->name))
> +		ret = -EMSGSIZE;
> +
> +	mutex_unlock(&tz->lock);
> +
> +	return ret;
> +}
> +
> +static int __thermal_genl_cmd_cdev_get(struct thermal_cooling_device
> *cdev,
> +				       void *data)
> +{
> +	struct sk_buff *msg = data;
> +
> +	if (nla_put_u32(msg, THERMAL_GENL_ATTR_CDEV_ID, cdev->id))
> +		return -EMSGSIZE;
> +
> +	if (nla_put_string(msg, THERMAL_GENL_ATTR_CDEV_NAME, cdev-
> >type))
> +		return -EMSGSIZE;
> +
> +	return 0;
> +}
> +
> +static int thermal_genl_cmd_cdev_get(struct param *p)
> +{
> +	struct sk_buff *msg = p->msg;
> +	struct nlattr *start_cdev;
> +	int ret;
> +
> +	start_cdev = nla_nest_start(msg, THERMAL_GENL_ATTR_CDEV);
> +	if (!start_cdev)
> +		return -EMSGSIZE;
> +
> +	ret =
> for_each_thermal_cooling_device(__thermal_genl_cmd_cdev_get, msg);
> +	if (ret)
> +		goto out_cancel_nest;
> +
> +	nla_nest_end(msg, start_cdev);
> +
> +	return 0;
> +out_cancel_nest:
> +	nla_nest_cancel(msg, start_cdev);
> +
> +	return ret;
> +}
> +
> +static cb_t cmd_cb[] = {
> +	[THERMAL_GENL_CMD_TZ_GET_ID]	= thermal_genl_cmd_tz_get_id,
> +	[THERMAL_GENL_CMD_TZ_GET_TRIP]	=
> thermal_genl_cmd_tz_get_trip,
> +	[THERMAL_GENL_CMD_TZ_GET_TEMP]	=
> thermal_genl_cmd_tz_get_temp,
> +	[THERMAL_GENL_CMD_TZ_GET_GOV]	=
> thermal_genl_cmd_tz_get_gov,
> +	[THERMAL_GENL_CMD_CDEV_GET]	= thermal_genl_cmd_cdev_get,
> +};
> +
> +static int thermal_genl_cmd_dumpit(struct sk_buff *skb,
> +				   struct netlink_callback *cb)
> +{
> +	struct param p = { .msg = skb };
> +	const struct genl_dumpit_info *info = genl_dumpit_info(cb);
> +	int cmd = info->ops->cmd;
> +	int ret = -EMSGSIZE;
> +	void *hdr;
> +
> +	hdr = genlmsg_put(skb, 0, 0, &thermal_gnl_family, 0, cmd);
> +	if (!hdr)
> +		return -EMSGSIZE;
> +
> +	ret = cmd_cb[cmd](&p);
> +	if (ret)
> +		goto out_cancel_msg;
> +
> +	genlmsg_end(skb, hdr);
> +
> +	return 0;
> +
> +out_cancel_msg:
> +	genlmsg_cancel(skb, hdr);
> +
> +	return ret;
> +}
> +
> +static int thermal_genl_cmd_doit(struct sk_buff *skb,
> +				 struct genl_info *info)
> +{
> +	struct param p = { .attrs = info->attrs };
> +	struct sk_buff *msg;
> +	void *hdr;
> +	int cmd = info->genlhdr->cmd;
> +	int ret = -EMSGSIZE;
> +
> +	msg = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
> +	if (!msg)
> +		return -ENOMEM;
> +	p.msg = msg;
> +
> +	hdr = genlmsg_put_reply(msg, info, &thermal_gnl_family, 0,
> cmd);
> +	if (!hdr)
> +		goto out_free_msg;
> +
> +	ret = cmd_cb[cmd](&p);
> +	if (ret)
> +		goto out_cancel_msg;
> +
> +	genlmsg_end(msg, hdr);
> +
> +	return genlmsg_reply(msg, info);
> +
> +out_cancel_msg:
> +	genlmsg_cancel(msg, hdr);
> +out_free_msg:
> +	nlmsg_free(msg);
> +
> +	return ret;
> +}
> +
> +static const struct genl_ops thermal_genl_ops[] = {
> +	{
> +		.cmd = THERMAL_GENL_CMD_TZ_GET_ID,
> +		.validate = GENL_DONT_VALIDATE_STRICT |
> GENL_DONT_VALIDATE_DUMP,
> +		.dumpit = thermal_genl_cmd_dumpit,
> +	},
> +	{
> +		.cmd = THERMAL_GENL_CMD_TZ_GET_TRIP,
> +		.validate = GENL_DONT_VALIDATE_STRICT |
> GENL_DONT_VALIDATE_DUMP,
> +		.doit = thermal_genl_cmd_doit,
> +	},
> +	{
> +		.cmd = THERMAL_GENL_CMD_TZ_GET_TEMP,
> +		.validate = GENL_DONT_VALIDATE_STRICT |
> GENL_DONT_VALIDATE_DUMP,
> +		.doit = thermal_genl_cmd_doit,
> +	},
> +	{
> +		.cmd = THERMAL_GENL_CMD_TZ_GET_GOV,
> +		.validate = GENL_DONT_VALIDATE_STRICT |
> GENL_DONT_VALIDATE_DUMP,
> +		.doit = thermal_genl_cmd_doit,
> +	},
> +	{
> +		.cmd = THERMAL_GENL_CMD_CDEV_GET,
> +		.validate = GENL_DONT_VALIDATE_STRICT |
> GENL_DONT_VALIDATE_DUMP,
> +		.dumpit = thermal_genl_cmd_dumpit,
> +	},
> +};
> +
> +static struct genl_family thermal_gnl_family __ro_after_init = {
> +	.hdrsize	= 0,
> +	.name		= THERMAL_GENL_FAMILY_NAME,
> +	.version	= THERMAL_GENL_VERSION,
> +	.maxattr	= THERMAL_GENL_ATTR_MAX,
> +	.policy		= thermal_genl_policy,
> +	.ops		= thermal_genl_ops,
> +	.n_ops		= ARRAY_SIZE(thermal_genl_ops),
> +	.mcgrps		= thermal_genl_mcgrps,
> +	.n_mcgrps	= ARRAY_SIZE(thermal_genl_mcgrps),
> +};
> +
> +static int __init thermal_netlink_init(void)
> +{
> +	return genl_register_family(&thermal_gnl_family);
> +}
> +core_initcall(thermal_netlink_init);
> diff --git a/include/linux/thermal.h b/include/linux/thermal.h
> index 216185bb3014..3d4d8ae8c16a 100644
> --- a/include/linux/thermal.h
> +++ b/include/linux/thermal.h
> @@ -37,18 +37,6 @@ struct thermal_cooling_device;
>  struct thermal_instance;
>  struct thermal_attr;
>  
> -enum thermal_device_mode {
> -	THERMAL_DEVICE_DISABLED = 0,
> -	THERMAL_DEVICE_ENABLED,
> -};
> -
> -enum thermal_trip_type {
> -	THERMAL_TRIP_ACTIVE = 0,
> -	THERMAL_TRIP_PASSIVE,
> -	THERMAL_TRIP_HOT,
> -	THERMAL_TRIP_CRITICAL,
> -};
> -
>  enum thermal_trend {
>  	THERMAL_TREND_STABLE, /* temperature is stable */
>  	THERMAL_TREND_RAISING, /* temperature is raising */
> @@ -303,11 +291,6 @@ struct thermal_zone_params {
>  	int offset;
>  };
>  
> -struct thermal_genl_event {
> -	u32 orig;
> -	enum events event;
> -};
> -
>  /**
>   * struct thermal_zone_of_device_ops - scallbacks for handling DT
> based zones
>   *
> diff --git a/include/uapi/linux/thermal.h
> b/include/uapi/linux/thermal.h
> index 96218378dda8..4e2112ae2c91 100644
> --- a/include/uapi/linux/thermal.h
> +++ b/include/uapi/linux/thermal.h
> @@ -4,31 +4,87 @@
>  
>  #define THERMAL_NAME_LENGTH	20
>  
> -/* Adding event notification support elements */
> -#define THERMAL_GENL_FAMILY_NAME                "thermal_event"
> -#define THERMAL_GENL_VERSION                    0x01
> -#define THERMAL_GENL_MCAST_GROUP_NAME           "thermal_mc_grp"
> -
> -/* Events supported by Thermal Netlink */
> -enum events {
> -	THERMAL_AUX0,
> -	THERMAL_AUX1,
> -	THERMAL_CRITICAL,
> -	THERMAL_DEV_FAULT,
> +enum thermal_device_mode {
> +	THERMAL_DEVICE_DISABLED = 0,
> +	THERMAL_DEVICE_ENABLED,
> +};
> +
> +enum thermal_trip_type {
> +	THERMAL_TRIP_ACTIVE = 0,
> +	THERMAL_TRIP_PASSIVE,
> +	THERMAL_TRIP_HOT,
> +	THERMAL_TRIP_CRITICAL,
>  };
>  
> -/* attributes of thermal_genl_family */
> -enum {
> +/* Adding event notification support elements */
> +#define THERMAL_GENL_FAMILY_NAME		"thermal"
> +#define THERMAL_GENL_VERSION			0x01
> +#define THERMAL_GENL_SAMPLING_GROUP_NAME	"sampling"
> +#define THERMAL_GENL_EVENT_GROUP_NAME		"event"
> +
> +/* Attributes of thermal_genl_family */
> +enum thermal_genl_attr {
>  	THERMAL_GENL_ATTR_UNSPEC,
> -	THERMAL_GENL_ATTR_EVENT,
> +	THERMAL_GENL_ATTR_TZ,
> +	THERMAL_GENL_ATTR_TZ_ID,
> +	THERMAL_GENL_ATTR_TZ_TEMP,
> +	THERMAL_GENL_ATTR_TZ_TRIP,
> +	THERMAL_GENL_ATTR_TZ_TRIP_ID,
> +	THERMAL_GENL_ATTR_TZ_TRIP_TYPE,
> +	THERMAL_GENL_ATTR_TZ_TRIP_TEMP,
> +	THERMAL_GENL_ATTR_TZ_TRIP_HYST,
> +	THERMAL_GENL_ATTR_TZ_MODE,
> +	THERMAL_GENL_ATTR_TZ_NAME,
> +	THERMAL_GENL_ATTR_TZ_CDEV_WEIGHT,
> +	THERMAL_GENL_ATTR_TZ_GOV,
> +	THERMAL_GENL_ATTR_TZ_GOV_NAME,
> +	THERMAL_GENL_ATTR_CDEV,
> +	THERMAL_GENL_ATTR_CDEV_ID,
> +	THERMAL_GENL_ATTR_CDEV_CUR_STATE,
> +	THERMAL_GENL_ATTR_CDEV_MAX_STATE,
> +	THERMAL_GENL_ATTR_CDEV_MIN_STATE,
> +	THERMAL_GENL_ATTR_CDEV_NAME,
> +	THERMAL_GENL_ATTR_GOV_NAME,
> +
>  	__THERMAL_GENL_ATTR_MAX,
>  };
>  #define THERMAL_GENL_ATTR_MAX (__THERMAL_GENL_ATTR_MAX - 1)
>  
> -/* commands supported by the thermal_genl_family */
> -enum {
> +enum thermal_genl_sampling {
> +	THERMAL_GENL_SAMPLING_TEMP,
> +	__THERMAL_GENL_SAMPLING_MAX,
> +};
> +#define THERMAL_GENL_SAMPLING_MAX (__THERMAL_GENL_SAMPLING_MAX - 1)
> +
> +/* Events of thermal_genl_family */
> +enum thermal_genl_event {
> +	THERMAL_GENL_EVENT_UNSPEC,
> +	THERMAL_GENL_EVENT_TZ_CREATE,		/* Thermal zone
> creation */
> +	THERMAL_GENL_EVENT_TZ_DELETE,		/* Thermal zone
> deletion */
> +	THERMAL_GENL_EVENT_TZ_DISABLE,		/* Thermal zone
> disabed */
> +	THERMAL_GENL_EVENT_TZ_ENABLE,		/* Thermal zone
> enabled */
> +	THERMAL_GENL_EVENT_TZ_TRIP_UP,		/* Trip point crossed
> the way up */
> +	THERMAL_GENL_EVENT_TZ_TRIP_DOWN,	/* Trip point crossed the way
> down */
> +	THERMAL_GENL_EVENT_TZ_TRIP_CHANGE,	/* Trip point changed
> */
> +	THERMAL_GENL_EVENT_TZ_TRIP_ADD,		/* Trip point added
> */
> +	THERMAL_GENL_EVENT_TZ_TRIP_DELETE,	/* Trip point deleted
> */
> +	THERMAL_GENL_EVENT_CDEV_ADD,		/* Cdev bound to the
> thermal zone */
> +	THERMAL_GENL_EVENT_CDEV_DELETE,		/* Cdev unbound */
> +	THERMAL_GENL_EVENT_CDEV_UPDATE,		/* Cdev state updated
> */
> +	THERMAL_GENL_EVENT_TZ_GOV_CHANGE,	/* Governor policy
> changed  */
> +	__THERMAL_GENL_EVENT_MAX,
> +};
> +#define THERMAL_GENL_EVENT_MAX (__THERMAL_GENL_EVENT_MAX - 1)
> +
> +/* Commands supported by the thermal_genl_family */
> +enum thermal_genl_cmd {
>  	THERMAL_GENL_CMD_UNSPEC,
> -	THERMAL_GENL_CMD_EVENT,
> +	THERMAL_GENL_CMD_TZ_GET_ID,	/* List of thermal zones id
> */
> +	THERMAL_GENL_CMD_TZ_GET_TRIP,	/* List of thermal trips */
> +	THERMAL_GENL_CMD_TZ_GET_TEMP,	/* Get the thermal zone
> temperature */
> +	THERMAL_GENL_CMD_TZ_GET_GOV,	/* Get the thermal zone
> governor */
> +	THERMAL_GENL_CMD_TZ_GET_MODE,	/* Get the thermal zone mode
> */
> +	THERMAL_GENL_CMD_CDEV_GET,	/* List of cdev id */
>  	__THERMAL_GENL_CMD_MAX,
>  };
>  #define THERMAL_GENL_CMD_MAX (__THERMAL_GENL_CMD_MAX - 1)