From 4cb18728709683c91a5f6f8d5f337bfb498b089a Mon Sep 17 00:00:00 2001 From: "R.Durgadoss" Date: Wed, 27 Oct 2010 03:33:29 +0530 Subject: [PATCH] thermal: Add event notification to thermal framework This patch adds event notification support to the generic thermal sysfs framework in the kernel. The notification is in the form of a netlink event. Signed-off-by: R.Durgadoss Signed-off-by: Len Brown --- Documentation/ABI/stable/thermal-notification | 4 + Documentation/thermal/sysfs-api.txt | 12 ++ drivers/thermal/Kconfig | 1 + drivers/thermal/thermal_sys.c | 103 +++++++++++++++++- include/linux/thermal.h | 32 ++++++ 5 files changed, 151 insertions(+), 1 deletion(-) create mode 100644 Documentation/ABI/stable/thermal-notification diff --git a/Documentation/ABI/stable/thermal-notification b/Documentation/ABI/stable/thermal-notification new file mode 100644 index 0000000000000..9723e8b7aeb31 --- /dev/null +++ b/Documentation/ABI/stable/thermal-notification @@ -0,0 +1,4 @@ +What: A notification mechanism for thermal related events +Description: + This interface enables notification for thermal related events. + The notification is in the form of a netlink event. diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt index cb3d15bc1aeb4..b61e46f449aa1 100644 --- a/Documentation/thermal/sysfs-api.txt +++ b/Documentation/thermal/sysfs-api.txt @@ -278,3 +278,15 @@ method, the sys I/F structure will be built like this: |---name: acpitz |---temp1_input: 37000 |---temp1_crit: 100000 + +4. Event Notification + +The framework includes a simple notification mechanism, in the form of a +netlink event. Netlink socket initialization is done during the _init_ +of the framework. Drivers which intend to use the notification mechanism +just need to call generate_netlink_event() with two arguments viz +(originator, event). Typically the originator will be an integer assigned +to a thermal_zone_device when it registers itself with the framework. The +event will be one of:{THERMAL_AUX0, THERMAL_AUX1, THERMAL_CRITICAL, +THERMAL_DEV_FAULT}. Notification can be sent when the current temperature +crosses any of the configured thresholds. diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index bf7c687519ef4..f7a5dba3ca23a 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -4,6 +4,7 @@ menuconfig THERMAL tristate "Generic Thermal sysfs driver" + depends on NET help Generic Thermal Sysfs driver offers a generic mechanism for thermal management. Usually it's made up of one or more thermal diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c index 13c72c629329c..760e045c93c8f 100644 --- a/drivers/thermal/thermal_sys.c +++ b/drivers/thermal/thermal_sys.c @@ -32,6 +32,8 @@ #include #include #include +#include +#include MODULE_AUTHOR("Zhang Rui"); MODULE_DESCRIPTION("Generic thermal management sysfs support"); @@ -58,6 +60,22 @@ static LIST_HEAD(thermal_tz_list); static LIST_HEAD(thermal_cdev_list); static DEFINE_MUTEX(thermal_list_lock); +static unsigned int thermal_event_seqnum; + +static struct genl_family thermal_event_genl_family = { + .id = GENL_ID_GENERATE, + .name = THERMAL_GENL_FAMILY_NAME, + .version = THERMAL_GENL_VERSION, + .maxattr = THERMAL_GENL_ATTR_MAX, +}; + +static struct genl_multicast_group thermal_event_mcgrp = { + .name = THERMAL_GENL_MCAST_GROUP_NAME, +}; + +static int genetlink_init(void); +static void genetlink_exit(void); + static int get_idr(struct idr *idr, struct mutex *lock, int *id) { int err; @@ -1214,6 +1232,82 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz) EXPORT_SYMBOL(thermal_zone_device_unregister); +int generate_netlink_event(u32 orig, enum events event) +{ + struct sk_buff *skb; + struct nlattr *attr; + struct thermal_genl_event *thermal_event; + void *msg_header; + int size; + int result; + + /* allocate memory */ + size = nla_total_size(sizeof(struct thermal_genl_event)) + \ + nla_total_size(0); + + skb = genlmsg_new(size, GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + /* add the genetlink message header */ + msg_header = genlmsg_put(skb, 0, thermal_event_seqnum++, + &thermal_event_genl_family, 0, + THERMAL_GENL_CMD_EVENT); + if (!msg_header) { + nlmsg_free(skb); + return -ENOMEM; + } + + /* fill the data */ + attr = nla_reserve(skb, THERMAL_GENL_ATTR_EVENT, \ + sizeof(struct thermal_genl_event)); + + if (!attr) { + nlmsg_free(skb); + return -EINVAL; + } + + thermal_event = nla_data(attr); + if (!thermal_event) { + nlmsg_free(skb); + return -EINVAL; + } + + memset(thermal_event, 0, sizeof(struct thermal_genl_event)); + + thermal_event->orig = orig; + thermal_event->event = event; + + /* send multicast genetlink message */ + result = genlmsg_end(skb, msg_header); + if (result < 0) { + nlmsg_free(skb); + return result; + } + + result = genlmsg_multicast(skb, 0, thermal_event_mcgrp.id, GFP_ATOMIC); + if (result) + printk(KERN_INFO "failed to send netlink event:%d", result); + + return result; +} +EXPORT_SYMBOL(generate_netlink_event); + +static int genetlink_init(void) +{ + int result; + + result = genl_register_family(&thermal_event_genl_family); + if (result) + return result; + + result = genl_register_mc_group(&thermal_event_genl_family, + &thermal_event_mcgrp); + if (result) + genl_unregister_family(&thermal_event_genl_family); + return result; +} + static int __init thermal_init(void) { int result = 0; @@ -1225,9 +1319,15 @@ static int __init thermal_init(void) mutex_destroy(&thermal_idr_lock); mutex_destroy(&thermal_list_lock); } + result = genetlink_init(); return result; } +static void genetlink_exit(void) +{ + genl_unregister_family(&thermal_event_genl_family); +} + static void __exit thermal_exit(void) { class_unregister(&thermal_class); @@ -1235,7 +1335,8 @@ static void __exit thermal_exit(void) idr_destroy(&thermal_cdev_idr); mutex_destroy(&thermal_idr_lock); mutex_destroy(&thermal_list_lock); + genetlink_exit(); } -subsys_initcall(thermal_init); +fs_initcall(thermal_init); module_exit(thermal_exit); diff --git a/include/linux/thermal.h b/include/linux/thermal.h index 1de8b9eb841ba..7846449612795 100644 --- a/include/linux/thermal.h +++ b/include/linux/thermal.h @@ -127,6 +127,37 @@ struct thermal_zone_device { struct thermal_hwmon_attr temp_crit; /* hwmon sys attr */ #endif }; +/* 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_group" + +enum events { + THERMAL_AUX0, + THERMAL_AUX1, + THERMAL_CRITICAL, + THERMAL_DEV_FAULT, +}; + +struct thermal_genl_event { + u32 orig; + enum events event; +}; +/* attributes of thermal_genl_family */ +enum { + THERMAL_GENL_ATTR_UNSPEC, + THERMAL_GENL_ATTR_EVENT, + __THERMAL_GENL_ATTR_MAX, +}; +#define THERMAL_GENL_ATTR_MAX (__THERMAL_GENL_ATTR_MAX - 1) + +/* commands supported by the thermal_genl_family */ +enum { + THERMAL_GENL_CMD_UNSPEC, + THERMAL_GENL_CMD_EVENT, + __THERMAL_GENL_CMD_MAX, +}; +#define THERMAL_GENL_CMD_MAX (__THERMAL_GENL_CMD_MAX - 1) struct thermal_zone_device *thermal_zone_device_register(char *, int, void *, struct @@ -146,5 +177,6 @@ struct thermal_cooling_device *thermal_cooling_device_register(char *, void *, thermal_cooling_device_ops *); void thermal_cooling_device_unregister(struct thermal_cooling_device *); +extern int generate_netlink_event(u32 orig, enum events event); #endif /* __THERMAL_H__ */