2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-25 05:34:00 +08:00
linux-next/drivers/thermal/thermal_hwmon.c
Sascha Hauer 17e8351a77 thermal: consistently use int for temperatures
The thermal code uses int, long and unsigned long for temperatures
in different places.

Using an unsigned type limits the thermal framework to positive
temperatures without need. Also several drivers currently will report
temperatures near UINT_MAX for temperatures below 0°C. This will probably
immediately shut the machine down due to overtemperature if started below
0°C.

'long' is 64bit on several architectures. This is not needed since INT_MAX °mC
is above the melting point of all known materials.

Consistently use a plain 'int' for temperatures throughout the thermal code and
the drivers. This only changes the places in the drivers where the temperature
is passed around as pointer, when drivers internally use another type this is
not changed.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
Reviewed-by: Darren Hart <dvhart@linux.intel.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Peter Feuerer <peter@piie.net>
Cc: Punit Agrawal <punit.agrawal@arm.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Jean Delvare <jdelvare@suse.de>
Cc: Peter Feuerer <peter@piie.net>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Lukasz Majewski <l.majewski@samsung.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: linux-acpi@vger.kernel.org
Cc: platform-driver-x86@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-omap@vger.kernel.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: lm-sensors@lm-sensors.org
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2015-08-03 23:15:50 +08:00

273 lines
7.4 KiB
C

/*
* thermal_hwmon.c - Generic Thermal Management hwmon support.
*
* Code based on Intel thermal_core.c. Copyrights of the original code:
* Copyright (C) 2008 Intel Corp
* Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
* Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
*
* Copyright (C) 2013 Texas Instruments
* Copyright (C) 2013 Eduardo Valentin <eduardo.valentin@ti.com>
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that 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.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#include <linux/hwmon.h>
#include <linux/thermal.h>
#include <linux/slab.h>
#include <linux/err.h>
#include "thermal_hwmon.h"
/* hwmon sys I/F */
/* thermal zone devices with the same type share one hwmon device */
struct thermal_hwmon_device {
char type[THERMAL_NAME_LENGTH];
struct device *device;
int count;
struct list_head tz_list;
struct list_head node;
};
struct thermal_hwmon_attr {
struct device_attribute attr;
char name[16];
};
/* one temperature input for each thermal zone */
struct thermal_hwmon_temp {
struct list_head hwmon_node;
struct thermal_zone_device *tz;
struct thermal_hwmon_attr temp_input; /* hwmon sys attr */
struct thermal_hwmon_attr temp_crit; /* hwmon sys attr */
};
static LIST_HEAD(thermal_hwmon_list);
static DEFINE_MUTEX(thermal_hwmon_list_lock);
static ssize_t
name_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct thermal_hwmon_device *hwmon = dev_get_drvdata(dev);
return sprintf(buf, "%s\n", hwmon->type);
}
static DEVICE_ATTR(name, 0444, name_show, NULL);
static ssize_t
temp_input_show(struct device *dev, struct device_attribute *attr, char *buf)
{
int temperature;
int ret;
struct thermal_hwmon_attr *hwmon_attr
= container_of(attr, struct thermal_hwmon_attr, attr);
struct thermal_hwmon_temp *temp
= container_of(hwmon_attr, struct thermal_hwmon_temp,
temp_input);
struct thermal_zone_device *tz = temp->tz;
ret = thermal_zone_get_temp(tz, &temperature);
if (ret)
return ret;
return sprintf(buf, "%d\n", temperature);
}
static ssize_t
temp_crit_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct thermal_hwmon_attr *hwmon_attr
= container_of(attr, struct thermal_hwmon_attr, attr);
struct thermal_hwmon_temp *temp
= container_of(hwmon_attr, struct thermal_hwmon_temp,
temp_crit);
struct thermal_zone_device *tz = temp->tz;
int temperature;
int ret;
ret = tz->ops->get_trip_temp(tz, 0, &temperature);
if (ret)
return ret;
return sprintf(buf, "%d\n", temperature);
}
static struct thermal_hwmon_device *
thermal_hwmon_lookup_by_type(const struct thermal_zone_device *tz)
{
struct thermal_hwmon_device *hwmon;
mutex_lock(&thermal_hwmon_list_lock);
list_for_each_entry(hwmon, &thermal_hwmon_list, node)
if (!strcmp(hwmon->type, tz->type)) {
mutex_unlock(&thermal_hwmon_list_lock);
return hwmon;
}
mutex_unlock(&thermal_hwmon_list_lock);
return NULL;
}
/* Find the temperature input matching a given thermal zone */
static struct thermal_hwmon_temp *
thermal_hwmon_lookup_temp(const struct thermal_hwmon_device *hwmon,
const struct thermal_zone_device *tz)
{
struct thermal_hwmon_temp *temp;
mutex_lock(&thermal_hwmon_list_lock);
list_for_each_entry(temp, &hwmon->tz_list, hwmon_node)
if (temp->tz == tz) {
mutex_unlock(&thermal_hwmon_list_lock);
return temp;
}
mutex_unlock(&thermal_hwmon_list_lock);
return NULL;
}
static bool thermal_zone_crit_temp_valid(struct thermal_zone_device *tz)
{
int temp;
return tz->ops->get_crit_temp && !tz->ops->get_crit_temp(tz, &temp);
}
int thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)
{
struct thermal_hwmon_device *hwmon;
struct thermal_hwmon_temp *temp;
int new_hwmon_device = 1;
int result;
hwmon = thermal_hwmon_lookup_by_type(tz);
if (hwmon) {
new_hwmon_device = 0;
goto register_sys_interface;
}
hwmon = kzalloc(sizeof(*hwmon), GFP_KERNEL);
if (!hwmon)
return -ENOMEM;
INIT_LIST_HEAD(&hwmon->tz_list);
strlcpy(hwmon->type, tz->type, THERMAL_NAME_LENGTH);
hwmon->device = hwmon_device_register(NULL);
if (IS_ERR(hwmon->device)) {
result = PTR_ERR(hwmon->device);
goto free_mem;
}
dev_set_drvdata(hwmon->device, hwmon);
result = device_create_file(hwmon->device, &dev_attr_name);
if (result)
goto free_mem;
register_sys_interface:
temp = kzalloc(sizeof(*temp), GFP_KERNEL);
if (!temp) {
result = -ENOMEM;
goto unregister_name;
}
temp->tz = tz;
hwmon->count++;
snprintf(temp->temp_input.name, sizeof(temp->temp_input.name),
"temp%d_input", hwmon->count);
temp->temp_input.attr.attr.name = temp->temp_input.name;
temp->temp_input.attr.attr.mode = 0444;
temp->temp_input.attr.show = temp_input_show;
sysfs_attr_init(&temp->temp_input.attr.attr);
result = device_create_file(hwmon->device, &temp->temp_input.attr);
if (result)
goto free_temp_mem;
if (thermal_zone_crit_temp_valid(tz)) {
snprintf(temp->temp_crit.name,
sizeof(temp->temp_crit.name),
"temp%d_crit", hwmon->count);
temp->temp_crit.attr.attr.name = temp->temp_crit.name;
temp->temp_crit.attr.attr.mode = 0444;
temp->temp_crit.attr.show = temp_crit_show;
sysfs_attr_init(&temp->temp_crit.attr.attr);
result = device_create_file(hwmon->device,
&temp->temp_crit.attr);
if (result)
goto unregister_input;
}
mutex_lock(&thermal_hwmon_list_lock);
if (new_hwmon_device)
list_add_tail(&hwmon->node, &thermal_hwmon_list);
list_add_tail(&temp->hwmon_node, &hwmon->tz_list);
mutex_unlock(&thermal_hwmon_list_lock);
return 0;
unregister_input:
device_remove_file(hwmon->device, &temp->temp_input.attr);
free_temp_mem:
kfree(temp);
unregister_name:
if (new_hwmon_device) {
device_remove_file(hwmon->device, &dev_attr_name);
hwmon_device_unregister(hwmon->device);
}
free_mem:
if (new_hwmon_device)
kfree(hwmon);
return result;
}
void thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
{
struct thermal_hwmon_device *hwmon;
struct thermal_hwmon_temp *temp;
hwmon = thermal_hwmon_lookup_by_type(tz);
if (unlikely(!hwmon)) {
/* Should never happen... */
dev_dbg(&tz->device, "hwmon device lookup failed!\n");
return;
}
temp = thermal_hwmon_lookup_temp(hwmon, tz);
if (unlikely(!temp)) {
/* Should never happen... */
dev_dbg(&tz->device, "temperature input lookup failed!\n");
return;
}
device_remove_file(hwmon->device, &temp->temp_input.attr);
if (thermal_zone_crit_temp_valid(tz))
device_remove_file(hwmon->device, &temp->temp_crit.attr);
mutex_lock(&thermal_hwmon_list_lock);
list_del(&temp->hwmon_node);
kfree(temp);
if (!list_empty(&hwmon->tz_list)) {
mutex_unlock(&thermal_hwmon_list_lock);
return;
}
list_del(&hwmon->node);
mutex_unlock(&thermal_hwmon_list_lock);
device_remove_file(hwmon->device, &dev_attr_name);
hwmon_device_unregister(hwmon->device);
kfree(hwmon);
}