From 27365a6c7d64a3bba22ee62109e4a071bbd7f933 Mon Sep 17 00:00:00 2001 From: Durgadoss R Date: Wed, 25 Jul 2012 10:10:59 +0800 Subject: Thermal: Add Hysteresis attributes The Linux Thermal Framework does not support hysteresis attributes. Most thermal sensors, today, have a hysteresis value associated with trip points. This patch adds hysteresis attributes on a per-trip-point basis, to the Thermal Framework. These attributes are optionally writable. Signed-off-by: Durgadoss R Signed-off-by: Zhang Rui Signed-off-by: Len Brown --- drivers/thermal/thermal_sys.c | 88 ++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 83 insertions(+), 5 deletions(-) (limited to 'drivers') diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c index 5feb3353213..2d7a9fe8f36 100644 --- a/drivers/thermal/thermal_sys.c +++ b/drivers/thermal/thermal_sys.c @@ -239,6 +239,52 @@ trip_point_temp_show(struct device *dev, struct device_attribute *attr, return sprintf(buf, "%ld\n", temperature); } +static ssize_t +trip_point_hyst_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct thermal_zone_device *tz = to_thermal_zone(dev); + int trip, ret; + unsigned long temperature; + + if (!tz->ops->set_trip_hyst) + return -EPERM; + + if (!sscanf(attr->attr.name, "trip_point_%d_hyst", &trip)) + return -EINVAL; + + if (kstrtoul(buf, 10, &temperature)) + return -EINVAL; + + /* + * We are not doing any check on the 'temperature' value + * here. The driver implementing 'set_trip_hyst' has to + * take care of this. + */ + ret = tz->ops->set_trip_hyst(tz, trip, temperature); + + return ret ? ret : count; +} + +static ssize_t +trip_point_hyst_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct thermal_zone_device *tz = to_thermal_zone(dev); + int trip, ret; + unsigned long temperature; + + if (!tz->ops->get_trip_hyst) + return -EPERM; + + if (!sscanf(attr->attr.name, "trip_point_%d_hyst", &trip)) + return -EINVAL; + + ret = tz->ops->get_trip_hyst(tz, trip, &temperature); + + return ret ? ret : sprintf(buf, "%ld\n", temperature); +} + static ssize_t passive_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) @@ -1091,21 +1137,29 @@ EXPORT_SYMBOL(thermal_zone_device_update); static int create_trip_attrs(struct thermal_zone_device *tz, int mask) { int indx; + int size = sizeof(struct thermal_attr) * tz->trips; - tz->trip_type_attrs = - kzalloc(sizeof(struct thermal_attr) * tz->trips, GFP_KERNEL); + tz->trip_type_attrs = kzalloc(size, GFP_KERNEL); if (!tz->trip_type_attrs) return -ENOMEM; - tz->trip_temp_attrs = - kzalloc(sizeof(struct thermal_attr) * tz->trips, GFP_KERNEL); + tz->trip_temp_attrs = kzalloc(size, GFP_KERNEL); if (!tz->trip_temp_attrs) { kfree(tz->trip_type_attrs); return -ENOMEM; } - for (indx = 0; indx < tz->trips; indx++) { + if (tz->ops->get_trip_hyst) { + tz->trip_hyst_attrs = kzalloc(size, GFP_KERNEL); + if (!tz->trip_hyst_attrs) { + kfree(tz->trip_type_attrs); + kfree(tz->trip_temp_attrs); + return -ENOMEM; + } + } + + for (indx = 0; indx < tz->trips; indx++) { /* create trip type attribute */ snprintf(tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH, "trip_point_%d_type", indx); @@ -1136,6 +1190,26 @@ static int create_trip_attrs(struct thermal_zone_device *tz, int mask) device_create_file(&tz->device, &tz->trip_temp_attrs[indx].attr); + + /* create Optional trip hyst attribute */ + if (!tz->ops->get_trip_hyst) + continue; + snprintf(tz->trip_hyst_attrs[indx].name, THERMAL_NAME_LENGTH, + "trip_point_%d_hyst", indx); + + sysfs_attr_init(&tz->trip_hyst_attrs[indx].attr.attr); + tz->trip_hyst_attrs[indx].attr.attr.name = + tz->trip_hyst_attrs[indx].name; + tz->trip_hyst_attrs[indx].attr.attr.mode = S_IRUGO; + tz->trip_hyst_attrs[indx].attr.show = trip_point_hyst_show; + if (tz->ops->set_trip_hyst) { + tz->trip_hyst_attrs[indx].attr.attr.mode |= S_IWUSR; + tz->trip_hyst_attrs[indx].attr.store = + trip_point_hyst_store; + } + + device_create_file(&tz->device, + &tz->trip_hyst_attrs[indx].attr); } return 0; } @@ -1149,9 +1223,13 @@ static void remove_trip_attrs(struct thermal_zone_device *tz) &tz->trip_type_attrs[indx].attr); device_remove_file(&tz->device, &tz->trip_temp_attrs[indx].attr); + if (tz->ops->get_trip_hyst) + device_remove_file(&tz->device, + &tz->trip_hyst_attrs[indx].attr); } kfree(tz->trip_type_attrs); kfree(tz->trip_temp_attrs); + kfree(tz->trip_hyst_attrs); } /** -- cgit v1.2.3-70-g09d2