mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-30 08:02:30 +00:00
9ec6dbfbdc
When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
145 lines
3.2 KiB
C
145 lines
3.2 KiB
C
/*
|
|
* ec_sys.c
|
|
*
|
|
* Copyright (C) 2010 SUSE Products GmbH/Novell
|
|
* Author:
|
|
* Thomas Renninger <trenn@suse.de>
|
|
*
|
|
* This work is licensed under the terms of the GNU GPL, version 2.
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/acpi.h>
|
|
#include <linux/debugfs.h>
|
|
#include <linux/module.h>
|
|
#include <linux/uaccess.h>
|
|
#include "internal.h"
|
|
|
|
MODULE_AUTHOR("Thomas Renninger <trenn@suse.de>");
|
|
MODULE_DESCRIPTION("ACPI EC sysfs access driver");
|
|
MODULE_LICENSE("GPL");
|
|
|
|
static bool write_support;
|
|
module_param(write_support, bool, 0644);
|
|
MODULE_PARM_DESC(write_support, "Dangerous, reboot and removal of battery may "
|
|
"be needed.");
|
|
|
|
#define EC_SPACE_SIZE 256
|
|
|
|
static struct dentry *acpi_ec_debugfs_dir;
|
|
|
|
static ssize_t acpi_ec_read_io(struct file *f, char __user *buf,
|
|
size_t count, loff_t *off)
|
|
{
|
|
/* Use this if support reading/writing multiple ECs exists in ec.c:
|
|
* struct acpi_ec *ec = ((struct seq_file *)f->private_data)->private;
|
|
*/
|
|
unsigned int size = EC_SPACE_SIZE;
|
|
loff_t init_off = *off;
|
|
int err = 0;
|
|
|
|
if (*off >= size)
|
|
return 0;
|
|
if (*off + count >= size) {
|
|
size -= *off;
|
|
count = size;
|
|
} else
|
|
size = count;
|
|
|
|
while (size) {
|
|
u8 byte_read;
|
|
err = ec_read(*off, &byte_read);
|
|
if (err)
|
|
return err;
|
|
if (put_user(byte_read, buf + *off - init_off)) {
|
|
if (*off - init_off)
|
|
return *off - init_off; /* partial read */
|
|
return -EFAULT;
|
|
}
|
|
*off += 1;
|
|
size--;
|
|
}
|
|
return count;
|
|
}
|
|
|
|
static ssize_t acpi_ec_write_io(struct file *f, const char __user *buf,
|
|
size_t count, loff_t *off)
|
|
{
|
|
/* Use this if support reading/writing multiple ECs exists in ec.c:
|
|
* struct acpi_ec *ec = ((struct seq_file *)f->private_data)->private;
|
|
*/
|
|
|
|
unsigned int size = count;
|
|
loff_t init_off = *off;
|
|
int err = 0;
|
|
|
|
if (!write_support)
|
|
return -EINVAL;
|
|
|
|
if (*off >= EC_SPACE_SIZE)
|
|
return 0;
|
|
if (*off + count >= EC_SPACE_SIZE) {
|
|
size = EC_SPACE_SIZE - *off;
|
|
count = size;
|
|
}
|
|
|
|
while (size) {
|
|
u8 byte_write;
|
|
if (get_user(byte_write, buf + *off - init_off)) {
|
|
if (*off - init_off)
|
|
return *off - init_off; /* partial write */
|
|
return -EFAULT;
|
|
}
|
|
err = ec_write(*off, byte_write);
|
|
if (err)
|
|
return err;
|
|
|
|
*off += 1;
|
|
size--;
|
|
}
|
|
return count;
|
|
}
|
|
|
|
static const struct file_operations acpi_ec_io_ops = {
|
|
.owner = THIS_MODULE,
|
|
.open = simple_open,
|
|
.read = acpi_ec_read_io,
|
|
.write = acpi_ec_write_io,
|
|
.llseek = default_llseek,
|
|
};
|
|
|
|
static void acpi_ec_add_debugfs(struct acpi_ec *ec, unsigned int ec_device_count)
|
|
{
|
|
struct dentry *dev_dir;
|
|
char name[64];
|
|
umode_t mode = 0400;
|
|
|
|
if (ec_device_count == 0)
|
|
acpi_ec_debugfs_dir = debugfs_create_dir("ec", NULL);
|
|
|
|
sprintf(name, "ec%u", ec_device_count);
|
|
dev_dir = debugfs_create_dir(name, acpi_ec_debugfs_dir);
|
|
|
|
debugfs_create_x32("gpe", 0444, dev_dir, &first_ec->gpe);
|
|
debugfs_create_bool("use_global_lock", 0444, dev_dir,
|
|
&first_ec->global_lock);
|
|
|
|
if (write_support)
|
|
mode = 0600;
|
|
debugfs_create_file("io", mode, dev_dir, ec, &acpi_ec_io_ops);
|
|
}
|
|
|
|
static int __init acpi_ec_sys_init(void)
|
|
{
|
|
if (first_ec)
|
|
acpi_ec_add_debugfs(first_ec, 0);
|
|
return 0;
|
|
}
|
|
|
|
static void __exit acpi_ec_sys_exit(void)
|
|
{
|
|
debugfs_remove_recursive(acpi_ec_debugfs_dir);
|
|
}
|
|
|
|
module_init(acpi_ec_sys_init);
|
|
module_exit(acpi_ec_sys_exit);
|