android_kernel_xiaomi_sm8350/drivers/misc/intel_menlow.c
Julia Lawall 3a8ca95e9d drivers/misc: elide a non-zero test on a result that is never 0
The function thermal_cooling_device_register always returns either a valid
pointer or a value made with ERR_PTR, so a test for non-zero on the result
will always succeed.

The problem was found using the following semantic match.
(http://www.emn.fr/x-info/coccinelle/)

//<smpl>
@a@
expression E, E1;
statement S,S1;
position p;
@@

E = thermal_cooling_device_register(...)
... when != E = E1
if@p (E) S else S1

@n@
position a.p;
expression E,E1;
statement S,S1;
@@

E = NULL
... when != E = E1
if@p (E) S else S1

@depends on !n@
expression E;
statement S,S1;
position a.p;
@@

* if@p (E)
  S else S1
//</smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Thomas Sujith <sujith.thomas@intel.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:04 -07:00

528 lines
13 KiB
C

/*
* intel_menlow.c - Intel menlow Driver for thermal management extension
*
* Copyright (C) 2008 Intel Corp
* Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
* Copyright (C) 2008 Zhang Rui <rui.zhang@intel.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.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* This driver creates the sys I/F for programming the sensors.
* It also implements the driver for intel menlow memory controller (hardware
* id is INT0002) which makes use of the platform specific ACPI methods
* to get/set bandwidth.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/pm.h>
#include <linux/thermal.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
MODULE_AUTHOR("Thomas Sujith");
MODULE_AUTHOR("Zhang Rui");
MODULE_DESCRIPTION("Intel Menlow platform specific driver");
MODULE_LICENSE("GPL");
/*
* Memory controller device control
*/
#define MEMORY_GET_BANDWIDTH "GTHS"
#define MEMORY_SET_BANDWIDTH "STHS"
#define MEMORY_ARG_CUR_BANDWIDTH 1
#define MEMORY_ARG_MAX_BANDWIDTH 0
static int memory_get_int_max_bandwidth(struct thermal_cooling_device *cdev,
unsigned long *max_state)
{
struct acpi_device *device = cdev->devdata;
acpi_handle handle = device->handle;
unsigned long value;
struct acpi_object_list arg_list;
union acpi_object arg;
acpi_status status = AE_OK;
arg_list.count = 1;
arg_list.pointer = &arg;
arg.type = ACPI_TYPE_INTEGER;
arg.integer.value = MEMORY_ARG_MAX_BANDWIDTH;
status = acpi_evaluate_integer(handle, MEMORY_GET_BANDWIDTH,
&arg_list, &value);
if (ACPI_FAILURE(status))
return -EFAULT;
*max_state = value - 1;
return 0;
}
static int memory_get_max_bandwidth(struct thermal_cooling_device *cdev,
char *buf)
{
unsigned long value;
if (memory_get_int_max_bandwidth(cdev, &value))
return -EINVAL;
return sprintf(buf, "%ld\n", value);
}
static int memory_get_cur_bandwidth(struct thermal_cooling_device *cdev,
char *buf)
{
struct acpi_device *device = cdev->devdata;
acpi_handle handle = device->handle;
unsigned long value;
struct acpi_object_list arg_list;
union acpi_object arg;
acpi_status status = AE_OK;
arg_list.count = 1;
arg_list.pointer = &arg;
arg.type = ACPI_TYPE_INTEGER;
arg.integer.value = MEMORY_ARG_CUR_BANDWIDTH;
status = acpi_evaluate_integer(handle, MEMORY_GET_BANDWIDTH,
&arg_list, &value);
if (ACPI_FAILURE(status))
return -EFAULT;
return sprintf(buf, "%ld\n", value);
}
static int memory_set_cur_bandwidth(struct thermal_cooling_device *cdev,
unsigned int state)
{
struct acpi_device *device = cdev->devdata;
acpi_handle handle = device->handle;
struct acpi_object_list arg_list;
union acpi_object arg;
acpi_status status;
int temp;
unsigned long max_state;
if (memory_get_int_max_bandwidth(cdev, &max_state))
return -EFAULT;
if (max_state < 0 || state > max_state)
return -EINVAL;
arg_list.count = 1;
arg_list.pointer = &arg;
arg.type = ACPI_TYPE_INTEGER;
arg.integer.value = state;
status =
acpi_evaluate_integer(handle, MEMORY_SET_BANDWIDTH, &arg_list,
(unsigned long *)&temp);
printk(KERN_INFO
"Bandwidth value was %d: status is %d\n", state, status);
if (ACPI_FAILURE(status))
return -EFAULT;
return 0;
}
static struct thermal_cooling_device_ops memory_cooling_ops = {
.get_max_state = memory_get_max_bandwidth,
.get_cur_state = memory_get_cur_bandwidth,
.set_cur_state = memory_set_cur_bandwidth,
};
/*
* Memory Device Management
*/
static int intel_menlow_memory_add(struct acpi_device *device)
{
int result = -ENODEV;
acpi_status status = AE_OK;
acpi_handle dummy;
struct thermal_cooling_device *cdev;
if (!device)
return -EINVAL;
status = acpi_get_handle(device->handle, MEMORY_GET_BANDWIDTH, &dummy);
if (ACPI_FAILURE(status))
goto end;
status = acpi_get_handle(device->handle, MEMORY_SET_BANDWIDTH, &dummy);
if (ACPI_FAILURE(status))
goto end;
cdev = thermal_cooling_device_register("Memory controller", device,
&memory_cooling_ops);
if (IS_ERR(cdev)) {
result = PTR_ERR(cdev);
goto end;
}
acpi_driver_data(device) = cdev;
result = sysfs_create_link(&device->dev.kobj,
&cdev->device.kobj, "thermal_cooling");
if (result)
goto unregister;
result = sysfs_create_link(&cdev->device.kobj,
&device->dev.kobj, "device");
if (result) {
sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
goto unregister;
}
end:
return result;
unregister:
thermal_cooling_device_unregister(cdev);
return result;
}
static int intel_menlow_memory_remove(struct acpi_device *device, int type)
{
struct thermal_cooling_device *cdev = acpi_driver_data(device);
if (!device || !cdev)
return -EINVAL;
sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
sysfs_remove_link(&cdev->device.kobj, "device");
thermal_cooling_device_unregister(cdev);
return 0;
}
static const struct acpi_device_id intel_menlow_memory_ids[] = {
{"INT0002", 0},
{"", 0},
};
static struct acpi_driver intel_menlow_memory_driver = {
.name = "intel_menlow_thermal_control",
.ids = intel_menlow_memory_ids,
.ops = {
.add = intel_menlow_memory_add,
.remove = intel_menlow_memory_remove,
},
};
/*
* Sensor control on menlow platform
*/
#define THERMAL_AUX0 0
#define THERMAL_AUX1 1
#define GET_AUX0 "GAX0"
#define GET_AUX1 "GAX1"
#define SET_AUX0 "SAX0"
#define SET_AUX1 "SAX1"
struct intel_menlow_attribute {
struct device_attribute attr;
struct device *device;
acpi_handle handle;
struct list_head node;
};
static LIST_HEAD(intel_menlow_attr_list);
static DEFINE_MUTEX(intel_menlow_attr_lock);
/*
* sensor_get_auxtrip - get the current auxtrip value from sensor
* @name: Thermalzone name
* @auxtype : AUX0/AUX1
* @buf: syfs buffer
*/
static int sensor_get_auxtrip(acpi_handle handle, int index, int *value)
{
acpi_status status;
if ((index != 0 && index != 1) || !value)
return -EINVAL;
status = acpi_evaluate_integer(handle, index ? GET_AUX1 : GET_AUX0,
NULL, (unsigned long *)value);
if (ACPI_FAILURE(status))
return -EIO;
return 0;
}
/*
* sensor_set_auxtrip - set the new auxtrip value to sensor
* @name: Thermalzone name
* @auxtype : AUX0/AUX1
* @buf: syfs buffer
*/
static int sensor_set_auxtrip(acpi_handle handle, int index, int value)
{
acpi_status status;
union acpi_object arg = {
ACPI_TYPE_INTEGER
};
struct acpi_object_list args = {
1, &arg
};
int temp;
if (index != 0 && index != 1)
return -EINVAL;
status = acpi_evaluate_integer(handle, index ? GET_AUX0 : GET_AUX1,
NULL, (unsigned long *)&temp);
if (ACPI_FAILURE(status))
return -EIO;
if ((index && value < temp) || (!index && value > temp))
return -EINVAL;
arg.integer.value = value;
status = acpi_evaluate_integer(handle, index ? SET_AUX1 : SET_AUX0,
&args, (unsigned long *)&temp);
if (ACPI_FAILURE(status))
return -EIO;
/* do we need to check the return value of SAX0/SAX1 ? */
return 0;
}
#define to_intel_menlow_attr(_attr) \
container_of(_attr, struct intel_menlow_attribute, attr)
static ssize_t aux0_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct intel_menlow_attribute *attr = to_intel_menlow_attr(dev_attr);
int value;
int result;
result = sensor_get_auxtrip(attr->handle, 0, &value);
return result ? result : sprintf(buf, "%lu", KELVIN_TO_CELSIUS(value));
}
static ssize_t aux1_show(struct device *dev,
struct device_attribute *dev_attr, char *buf)
{
struct intel_menlow_attribute *attr = to_intel_menlow_attr(dev_attr);
int value;
int result;
result = sensor_get_auxtrip(attr->handle, 1, &value);
return result ? result : sprintf(buf, "%lu", KELVIN_TO_CELSIUS(value));
}
static ssize_t aux0_store(struct device *dev,
struct device_attribute *dev_attr,
const char *buf, size_t count)
{
struct intel_menlow_attribute *attr = to_intel_menlow_attr(dev_attr);
int value;
int result;
/*Sanity check; should be a positive integer */
if (!sscanf(buf, "%d", &value))
return -EINVAL;
if (value < 0)
return -EINVAL;
result = sensor_set_auxtrip(attr->handle, 0, CELSIUS_TO_KELVIN(value));
return result ? result : count;
}
static ssize_t aux1_store(struct device *dev,
struct device_attribute *dev_attr,
const char *buf, size_t count)
{
struct intel_menlow_attribute *attr = to_intel_menlow_attr(dev_attr);
int value;
int result;
/*Sanity check; should be a positive integer */
if (!sscanf(buf, "%d", &value))
return -EINVAL;
if (value < 0)
return -EINVAL;
result = sensor_set_auxtrip(attr->handle, 1, CELSIUS_TO_KELVIN(value));
return result ? result : count;
}
/* BIOS can enable/disable the thermal user application in dabney platform */
#define BIOS_ENABLED "\\_TZ.GSTS"
static ssize_t bios_enabled_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
acpi_status status;
unsigned long bios_enabled;
status = acpi_evaluate_integer(NULL, BIOS_ENABLED, NULL, &bios_enabled);
if (ACPI_FAILURE(status))
return -ENODEV;
return sprintf(buf, "%s\n", bios_enabled ? "enabled" : "disabled");
}
static int intel_menlow_add_one_attribute(char *name, int mode, void *show,
void *store, struct device *dev,
acpi_handle handle)
{
struct intel_menlow_attribute *attr;
int result;
attr = kzalloc(sizeof(struct intel_menlow_attribute), GFP_KERNEL);
if (!attr)
return -ENOMEM;
attr->attr.attr.name = name;
attr->attr.attr.mode = mode;
attr->attr.show = show;
attr->attr.store = store;
attr->device = dev;
attr->handle = handle;
result = device_create_file(dev, &attr->attr);
if (result)
return result;
mutex_lock(&intel_menlow_attr_lock);
list_add_tail(&attr->node, &intel_menlow_attr_list);
mutex_unlock(&intel_menlow_attr_lock);
return 0;
}
static acpi_status intel_menlow_register_sensor(acpi_handle handle, u32 lvl,
void *context, void **rv)
{
acpi_status status;
acpi_handle dummy;
struct thermal_zone_device *thermal;
int result;
result = acpi_bus_get_private_data(handle, (void **)&thermal);
if (result)
return 0;
/* _TZ must have the AUX0/1 methods */
status = acpi_get_handle(handle, GET_AUX0, &dummy);
if (ACPI_FAILURE(status))
goto not_found;
status = acpi_get_handle(handle, SET_AUX0, &dummy);
if (ACPI_FAILURE(status))
goto not_found;
result = intel_menlow_add_one_attribute("aux0", 0644,
aux0_show, aux0_store,
&thermal->device, handle);
if (result)
return AE_ERROR;
status = acpi_get_handle(handle, GET_AUX1, &dummy);
if (ACPI_FAILURE(status))
goto not_found;
status = acpi_get_handle(handle, SET_AUX1, &dummy);
if (ACPI_FAILURE(status))
goto not_found;
result = intel_menlow_add_one_attribute("aux1", 0644,
aux1_show, aux1_store,
&thermal->device, handle);
if (result)
return AE_ERROR;
/*
* create the "dabney_enabled" attribute which means the user app
* should be loaded or not
*/
result = intel_menlow_add_one_attribute("bios_enabled", 0444,
bios_enabled_show, NULL,
&thermal->device, handle);
if (result)
return AE_ERROR;
not_found:
if (status == AE_NOT_FOUND)
return AE_OK;
else
return status;
}
static void intel_menlow_unregister_sensor(void)
{
struct intel_menlow_attribute *pos, *next;
mutex_lock(&intel_menlow_attr_lock);
list_for_each_entry_safe(pos, next, &intel_menlow_attr_list, node) {
list_del(&pos->node);
device_remove_file(pos->device, &pos->attr);
kfree(pos);
}
mutex_unlock(&intel_menlow_attr_lock);
return;
}
static int __init intel_menlow_module_init(void)
{
int result = -ENODEV;
acpi_status status;
unsigned long enable;
if (acpi_disabled)
return result;
/* Looking for the \_TZ.GSTS method */
status = acpi_evaluate_integer(NULL, BIOS_ENABLED, NULL, &enable);
if (ACPI_FAILURE(status) || !enable)
return -ENODEV;
/* Looking for ACPI device MEM0 with hardware id INT0002 */
result = acpi_bus_register_driver(&intel_menlow_memory_driver);
if (result)
return result;
/* Looking for sensors in each ACPI thermal zone */
status = acpi_walk_namespace(ACPI_TYPE_THERMAL, ACPI_ROOT_OBJECT,
ACPI_UINT32_MAX,
intel_menlow_register_sensor, NULL, NULL);
if (ACPI_FAILURE(status))
return -ENODEV;
return 0;
}
static void __exit intel_menlow_module_exit(void)
{
acpi_bus_unregister_driver(&intel_menlow_memory_driver);
intel_menlow_unregister_sensor();
}
module_init(intel_menlow_module_init);
module_exit(intel_menlow_module_exit);