linux/drivers/misc/sony-laptop.c
Andrew Morton 8607c673bd sony-laptop: fix uninitialised variable
drivers/misc/sony-laptop.c: In function 'sony_acpi_add':
drivers/misc/sony-laptop.c:456: warning: 'result' may be used uninitialized in this function

The compiler seems to actually be telling the truth this time.

Cc: Mattia Dongili <malattia@linux.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2007-03-07 03:05:13 -05:00

565 lines
14 KiB
C

/*
* ACPI Sony Notebook Control Driver (SNC)
*
* Copyright (C) 2004-2005 Stelian Pop <stelian@popies.net>
* Copyright (C) 2007 Mattia Dongili <malattia@linux.it>
*
* Parts of this driver inspired from asus_acpi.c and ibm_acpi.c
* which are copyrighted by their respective authors.
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/backlight.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <acpi/acpi_drivers.h>
#include <acpi/acpi_bus.h>
#include <asm/uaccess.h>
#define ACPI_SNC_CLASS "sony"
#define ACPI_SNC_HID "SNY5001"
#define ACPI_SNC_DRIVER_NAME "ACPI Sony Notebook Control Driver v0.4"
/* the device uses 1-based values, while the backlight subsystem uses
0-based values */
#define SONY_MAX_BRIGHTNESS 8
#define LOG_PFX KERN_WARNING "sony-laptop: "
MODULE_AUTHOR("Stelian Pop, Mattia Dongili");
MODULE_DESCRIPTION(ACPI_SNC_DRIVER_NAME);
MODULE_LICENSE("GPL");
static int debug;
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "set this to 1 (and RTFM) if you want to help "
"the development of this driver");
static ssize_t sony_acpi_show(struct device *, struct device_attribute *,
char *);
static ssize_t sony_acpi_store(struct device *, struct device_attribute *,
const char *, size_t);
static int boolean_validate(const int, const int);
static int brightness_default_validate(const int, const int);
#define SNC_VALIDATE_IN 0
#define SNC_VALIDATE_OUT 1
struct sony_acpi_value {
char *name; /* name of the entry */
char **acpiget; /* names of the ACPI get function */
char **acpiset; /* names of the ACPI set function */
int (*validate)(const int, const int); /* input/output validation */
int value; /* current setting */
int valid; /* Has ever been set */
int debug; /* active only in debug mode ? */
struct device_attribute devattr; /* sysfs atribute */
};
#define HANDLE_NAMES(_name, _values...) \
static char *snc_##_name[] = { _values, NULL }
#define SONY_ACPI_VALUE(_name, _getters, _setters, _validate, _debug) \
{ \
.name = __stringify(_name), \
.acpiget = _getters, \
.acpiset = _setters, \
.validate = _validate, \
.debug = _debug, \
.devattr = __ATTR(_name, 0, sony_acpi_show, sony_acpi_store), \
}
#define SONY_ACPI_VALUE_NULL { .name = NULL }
HANDLE_NAMES(fnkey_get, "GHKE");
HANDLE_NAMES(brightness_def_get, "GPBR");
HANDLE_NAMES(brightness_def_set, "SPBR");
HANDLE_NAMES(cdpower_get, "GCDP");
HANDLE_NAMES(cdpower_set, "SCDP", "CDPW");
HANDLE_NAMES(audiopower_get, "GAZP");
HANDLE_NAMES(audiopower_set, "AZPW");
HANDLE_NAMES(lanpower_get, "GLNP");
HANDLE_NAMES(lanpower_set, "LNPW");
HANDLE_NAMES(PID_get, "GPID");
HANDLE_NAMES(CTR_get, "GCTR");
HANDLE_NAMES(CTR_set, "SCTR");
HANDLE_NAMES(PCR_get, "GPCR");
HANDLE_NAMES(PCR_set, "SPCR");
HANDLE_NAMES(CMI_get, "GCMI");
HANDLE_NAMES(CMI_set, "SCMI");
static struct sony_acpi_value sony_acpi_values[] = {
SONY_ACPI_VALUE(brightness_default, snc_brightness_def_get,
snc_brightness_def_set, brightness_default_validate, 0),
SONY_ACPI_VALUE(fnkey, snc_fnkey_get, NULL, NULL, 0),
SONY_ACPI_VALUE(cdpower, snc_cdpower_get, snc_cdpower_set, boolean_validate, 0),
SONY_ACPI_VALUE(audiopower, snc_audiopower_get, snc_audiopower_set,
boolean_validate, 0),
SONY_ACPI_VALUE(lanpower, snc_lanpower_get, snc_lanpower_set,
boolean_validate, 1),
/* unknown methods */
SONY_ACPI_VALUE(PID, snc_PID_get, NULL, NULL, 1),
SONY_ACPI_VALUE(CTR, snc_CTR_get, snc_CTR_set, NULL, 1),
SONY_ACPI_VALUE(PCR, snc_PCR_get, snc_PCR_set, NULL, 1),
SONY_ACPI_VALUE(CMI, snc_CMI_get, snc_CMI_set, NULL, 1),
SONY_ACPI_VALUE_NULL
};
static acpi_handle sony_acpi_handle;
static struct acpi_device *sony_acpi_acpi_device = NULL;
/*
* acpi_evaluate_object wrappers
*/
static int acpi_callgetfunc(acpi_handle handle, char *name, int *result)
{
struct acpi_buffer output;
union acpi_object out_obj;
acpi_status status;
output.length = sizeof(out_obj);
output.pointer = &out_obj;
status = acpi_evaluate_object(handle, name, NULL, &output);
if ((status == AE_OK) && (out_obj.type == ACPI_TYPE_INTEGER)) {
*result = out_obj.integer.value;
return 0;
}
printk(LOG_PFX "acpi_callreadfunc failed\n");
return -1;
}
static int acpi_callsetfunc(acpi_handle handle, char *name, int value,
int *result)
{
struct acpi_object_list params;
union acpi_object in_obj;
struct acpi_buffer output;
union acpi_object out_obj;
acpi_status status;
params.count = 1;
params.pointer = &in_obj;
in_obj.type = ACPI_TYPE_INTEGER;
in_obj.integer.value = value;
output.length = sizeof(out_obj);
output.pointer = &out_obj;
status = acpi_evaluate_object(handle, name, &params, &output);
if (status == AE_OK) {
if (result != NULL) {
if (out_obj.type != ACPI_TYPE_INTEGER) {
printk(LOG_PFX "acpi_evaluate_object bad "
"return type\n");
return -1;
}
*result = out_obj.integer.value;
}
return 0;
}
printk(LOG_PFX "acpi_evaluate_object failed\n");
return -1;
}
/*
* sony_acpi_values input/output validate functions
*/
/* brightness_default_validate:
*
* manipulate input output values to keep consistency with the
* backlight framework for which brightness values are 0-based.
*/
static int brightness_default_validate(const int direction, const int value)
{
switch (direction) {
case SNC_VALIDATE_OUT:
return value - 1;
case SNC_VALIDATE_IN:
if (value >= 0 && value < SONY_MAX_BRIGHTNESS)
return value + 1;
}
return -EINVAL;
}
/* boolean_validate:
*
* on input validate boolean values 0/1, on output just pass the
* received value.
*/
static int boolean_validate(const int direction, const int value)
{
if (direction == SNC_VALIDATE_IN) {
if (value != 0 && value != 1)
return -EINVAL;
}
return value;
}
/*
* Sysfs show/store common to all sony_acpi_values
*/
static ssize_t sony_acpi_show(struct device *dev, struct device_attribute *attr,
char *buffer)
{
int value;
struct sony_acpi_value *item =
container_of(attr, struct sony_acpi_value, devattr);
if (!*item->acpiget)
return -EIO;
if (acpi_callgetfunc(sony_acpi_handle, *item->acpiget, &value) < 0)
return -EIO;
if (item->validate)
value = item->validate(SNC_VALIDATE_OUT, value);
return snprintf(buffer, PAGE_SIZE, "%d\n", value);
}
static ssize_t sony_acpi_store(struct device *dev,
struct device_attribute *attr,
const char *buffer, size_t count)
{
int value;
struct sony_acpi_value *item =
container_of(attr, struct sony_acpi_value, devattr);
if (!item->acpiset)
return -EIO;
if (count > 31)
return -EINVAL;
value = simple_strtoul(buffer, NULL, 10);
if (item->validate)
value = item->validate(SNC_VALIDATE_IN, value);
if (value < 0)
return value;
if (acpi_callsetfunc(sony_acpi_handle, *item->acpiset, value, NULL) < 0)
return -EIO;
item->value = value;
item->valid = 1;
return count;
}
/*
* Platform device
*/
static struct platform_driver sncpf_driver = {
.driver = {
.name = "sony-laptop",
.owner = THIS_MODULE,
}
};
static struct platform_device *sncpf_device;
static int sony_snc_pf_add(void)
{
acpi_handle handle;
struct sony_acpi_value *item;
int ret = 0;
ret = platform_driver_register(&sncpf_driver);
if (ret)
goto out;
sncpf_device = platform_device_alloc("sony-laptop", -1);
if (!sncpf_device) {
ret = -ENOMEM;
goto out_platform_registered;
}
ret = platform_device_add(sncpf_device);
if (ret)
goto out_platform_alloced;
for (item = sony_acpi_values; item->name; ++item) {
if (!debug && item->debug)
continue;
/* find the available acpiget as described in the DSDT */
for (; item->acpiget && *item->acpiget; ++item->acpiget) {
if (ACPI_SUCCESS(acpi_get_handle(sony_acpi_handle,
*item->acpiget,
&handle))) {
if (debug)
printk(LOG_PFX "Found %s getter: %s\n",
item->name, *item->acpiget);
item->devattr.attr.mode |= S_IRUGO;
break;
}
}
/* find the available acpiset as described in the DSDT */
for (; item->acpiset && *item->acpiset; ++item->acpiset) {
if (ACPI_SUCCESS(acpi_get_handle(sony_acpi_handle,
*item->acpiset,
&handle))) {
if (debug)
printk(LOG_PFX "Found %s setter: %s\n",
item->name, *item->acpiset);
item->devattr.attr.mode |= S_IWUSR;
break;
}
}
if (item->devattr.attr.mode != 0) {
ret =
device_create_file(&sncpf_device->dev,
&item->devattr);
if (ret)
goto out_sysfs;
}
}
return 0;
out_sysfs:
for (item = sony_acpi_values; item->name; ++item) {
device_remove_file(&sncpf_device->dev, &item->devattr);
}
platform_device_del(sncpf_device);
out_platform_alloced:
platform_device_put(sncpf_device);
out_platform_registered:
platform_driver_unregister(&sncpf_driver);
out:
return ret;
}
static void sony_snc_pf_remove(void)
{
struct sony_acpi_value *item;
for (item = sony_acpi_values; item->name; ++item) {
device_remove_file(&sncpf_device->dev, &item->devattr);
}
platform_device_del(sncpf_device);
platform_device_put(sncpf_device);
platform_driver_unregister(&sncpf_driver);
}
/*
* Backlight device
*/
static int sony_backlight_update_status(struct backlight_device *bd)
{
return acpi_callsetfunc(sony_acpi_handle, "SBRT",
bd->props.brightness + 1, NULL);
}
static int sony_backlight_get_brightness(struct backlight_device *bd)
{
int value;
if (acpi_callgetfunc(sony_acpi_handle, "GBRT", &value))
return 0;
/* brightness levels are 1-based, while backlight ones are 0-based */
return value - 1;
}
static struct backlight_device *sony_backlight_device;
static struct backlight_ops sony_backlight_ops = {
.update_status = sony_backlight_update_status,
.get_brightness = sony_backlight_get_brightness,
};
/*
* ACPI callbacks
*/
static void sony_acpi_notify(acpi_handle handle, u32 event, void *data)
{
if (debug)
printk(LOG_PFX "sony_acpi_notify, event: %d\n", event);
acpi_bus_generate_event(sony_acpi_acpi_device, 1, event);
}
static acpi_status sony_walk_callback(acpi_handle handle, u32 level,
void *context, void **return_value)
{
struct acpi_namespace_node *node;
union acpi_operand_object *operand;
node = (struct acpi_namespace_node *)handle;
operand = (union acpi_operand_object *)node->object;
printk(LOG_PFX "method: name: %4.4s, args %X\n", node->name.ascii,
(u32) operand->method.param_count);
return AE_OK;
}
/*
* ACPI device
*/
static int sony_acpi_resume(struct acpi_device *device)
{
struct sony_acpi_value *item;
for (item = sony_acpi_values; item->name; item++) {
int ret;
if (!item->valid)
continue;
ret = acpi_callsetfunc(sony_acpi_handle, *item->acpiset,
item->value, NULL);
if (ret < 0) {
printk("%s: %d\n", __FUNCTION__, ret);
break;
}
}
return 0;
}
static int sony_acpi_add(struct acpi_device *device)
{
acpi_status status;
int result = 0;
acpi_handle handle;
sony_acpi_acpi_device = device;
sony_acpi_handle = device->handle;
if (debug) {
status = acpi_walk_namespace(ACPI_TYPE_METHOD, sony_acpi_handle,
1, sony_walk_callback, NULL, NULL);
if (ACPI_FAILURE(status)) {
printk(LOG_PFX "unable to walk acpi resources\n");
result = -ENODEV;
goto outwalk;
}
}
status = acpi_install_notify_handler(sony_acpi_handle,
ACPI_DEVICE_NOTIFY,
sony_acpi_notify, NULL);
if (ACPI_FAILURE(status)) {
printk(LOG_PFX "unable to install notify handler\n");
result = -ENODEV;
goto outwalk;
}
if (ACPI_SUCCESS(acpi_get_handle(sony_acpi_handle, "GBRT", &handle))) {
sony_backlight_device = backlight_device_register("sony", NULL,
NULL,
&sony_backlight_ops);
if (IS_ERR(sony_backlight_device)) {
printk(LOG_PFX "unable to register backlight device\n");
sony_backlight_device = NULL;
} else {
sony_backlight_device->props.brightness =
sony_backlight_get_brightness
(sony_backlight_device);
sony_backlight_device->props.max_brightness =
SONY_MAX_BRIGHTNESS - 1;
}
}
if (sony_snc_pf_add())
goto outbacklight;
printk(KERN_INFO ACPI_SNC_DRIVER_NAME " successfully installed\n");
return 0;
outbacklight:
if (sony_backlight_device)
backlight_device_unregister(sony_backlight_device);
status = acpi_remove_notify_handler(sony_acpi_handle,
ACPI_DEVICE_NOTIFY,
sony_acpi_notify);
if (ACPI_FAILURE(status))
printk(LOG_PFX "unable to remove notify handler\n");
outwalk:
return result;
}
static int sony_acpi_remove(struct acpi_device *device, int type)
{
acpi_status status;
if (sony_backlight_device)
backlight_device_unregister(sony_backlight_device);
sony_acpi_acpi_device = NULL;
status = acpi_remove_notify_handler(sony_acpi_handle,
ACPI_DEVICE_NOTIFY,
sony_acpi_notify);
if (ACPI_FAILURE(status))
printk(LOG_PFX "unable to remove notify handler\n");
sony_snc_pf_remove();
printk(KERN_INFO ACPI_SNC_DRIVER_NAME " successfully removed\n");
return 0;
}
static struct acpi_driver sony_acpi_driver = {
.name = ACPI_SNC_DRIVER_NAME,
.class = ACPI_SNC_CLASS,
.ids = ACPI_SNC_HID,
.ops = {
.add = sony_acpi_add,
.remove = sony_acpi_remove,
.resume = sony_acpi_resume,
},
};
static int __init sony_acpi_init(void)
{
return acpi_bus_register_driver(&sony_acpi_driver);
}
static void __exit sony_acpi_exit(void)
{
acpi_bus_unregister_driver(&sony_acpi_driver);
}
module_init(sony_acpi_init);
module_exit(sony_acpi_exit);