[linux.git] / drivers / acpi / ec_sys.c

/*
 * ec_sys.c
 *
 * Copyright (C) 2010 SUSE Products GmbH/Novell
 * Author:
 *      Thomas Renninger <[email protected]>
 *
 * 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 <[email protected]>");
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 int 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);
		if (!acpi_ec_debugfs_dir)
			return -ENOMEM;
	}

	sprintf(name, "ec%u", ec_device_count);
	dev_dir = debugfs_create_dir(name, acpi_ec_debugfs_dir);
	if (!dev_dir) {
		if (ec_device_count != 0)
			goto error;
		return -ENOMEM;
	}

	if (!debugfs_create_x32("gpe", 0444, dev_dir, &first_ec->gpe))
		goto error;
	if (!debugfs_create_bool("use_global_lock", 0444, dev_dir,
				 &first_ec->global_lock))
		goto error;

	if (write_support)
		mode = 0600;
	if (!debugfs_create_file("io", mode, dev_dir, ec, &acpi_ec_io_ops))
		goto error;

	return 0;

error:
	debugfs_remove_recursive(acpi_ec_debugfs_dir);
	return -ENOMEM;
}

static int __init acpi_ec_sys_init(void)
{
	int err = 0;
	if (first_ec)
		err = acpi_ec_add_debugfs(first_ec, 0);
	else
		err = -ENODEV;
	return err;
}

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);
Commit	Line	Data
9827886d TR	1	/*
	2	* ec_sys.c
	3	*
	4	* Copyright (C) 2010 SUSE Products GmbH/Novell
	5	* Author:
	6	* Thomas Renninger <[email protected]>
	7	*
	8	* This work is licensed under the terms of the GNU GPL, version 2.
	9	*/
	10
1195a098 TR	11	#include <linux/kernel.h>
	12	#include <linux/acpi.h>
	13	#include <linux/debugfs.h>
cc4b859c	14	#include <linux/module.h>
ecde3003	15	#include <linux/uaccess.h>
1195a098 TR	16	#include "internal.h"
	17
	18	MODULE_AUTHOR("Thomas Renninger <[email protected]>");
	19	MODULE_DESCRIPTION("ACPI EC sysfs access driver");
	20	MODULE_LICENSE("GPL");
	21
500de3dd TR	22	static bool write_support;
	23	module_param(write_support, bool, 0644);
	24	MODULE_PARM_DESC(write_support, "Dangerous, reboot and removal of battery may "
	25	"be needed.");
	26
9827886d TR	27	#define EC_SPACE_SIZE 256
9827886d TR	28
1195a098 TR	29	static struct dentry *acpi_ec_debugfs_dir;
1195a098 TR	30
9827886d TR	31	static ssize_t acpi_ec_read_io(struct file f, char __user buf,
	32	size_t count, loff_t *off)
	33	{
	34	/* Use this if support reading/writing multiple ECs exists in ec.c:
	35	* struct acpi_ec ec = ((struct seq_file )f->private_data)->private;
	36	*/
	37	unsigned int size = EC_SPACE_SIZE;
9827886d TR	38	loff_t init_off = *off;
	39	int err = 0;
	40
	41	if (*off >= size)
	42	return 0;
	43	if (*off + count >= size) {
	44	size -= *off;
	45	count = size;
	46	} else
	47	size = count;
	48
	49	while (size) {
ecde3003 VK	50	u8 byte_read;
ecde3003 VK	51	err = ec_read(*off, &byte_read);
9827886d TR	52	if (err)
9827886d TR	53	return err;
ecde3003 VK	54	if (put_user(byte_read, buf + *off - init_off)) {
	55	if (*off - init_off)
	56	return off - init_off; / partial read */
	57	return -EFAULT;
	58	}
9827886d TR	59	*off += 1;
	60	size--;
	61	}
	62	return count;
	63	}
	64
	65	static ssize_t acpi_ec_write_io(struct file f, const char __user buf,
	66	size_t count, loff_t *off)
	67	{
	68	/* Use this if support reading/writing multiple ECs exists in ec.c:
	69	* struct acpi_ec ec = ((struct seq_file )f->private_data)->private;
	70	*/
	71
	72	unsigned int size = count;
	73	loff_t init_off = *off;
9827886d TR	74	int err = 0;
9827886d TR	75
1b6e75ee OD	76	if (!write_support)
	77	return -EINVAL;
	78
9827886d TR	79	if (*off >= EC_SPACE_SIZE)
	80	return 0;
	81	if (*off + count >= EC_SPACE_SIZE) {
	82	size = EC_SPACE_SIZE - *off;
	83	count = size;
	84	}
	85
	86	while (size) {
ecde3003 VK	87	u8 byte_write;
	88	if (get_user(byte_write, buf + *off - init_off)) {
	89	if (*off - init_off)
	90	return off - init_off; / partial write */
	91	return -EFAULT;
	92	}
9827886d TR	93	err = ec_write(*off, byte_write);
	94	if (err)
	95	return err;
	96
	97	*off += 1;
	98	size--;
	99	}
	100	return count;
	101	}
	102
9c8b04be	103	static const struct file_operations acpi_ec_io_ops = {
9827886d	104	.owner = THIS_MODULE,
234e3405	105	.open = simple_open,
9827886d TR	106	.read = acpi_ec_read_io,
9827886d TR	107	.write = acpi_ec_write_io,
6038f373	108	.llseek = default_llseek,
9827886d TR	109	};
9827886d TR	110
49894d8d	111	static int acpi_ec_add_debugfs(struct acpi_ec *ec, unsigned int ec_device_count)
1195a098 TR	112	{
	113	struct dentry *dev_dir;
	114	char name[64];
f4ae40a6	115	umode_t mode = 0400;
500de3dd	116
1195a098 TR	117	if (ec_device_count == 0) {
	118	acpi_ec_debugfs_dir = debugfs_create_dir("ec", NULL);
	119	if (!acpi_ec_debugfs_dir)
	120	return -ENOMEM;
	121	}
	122
	123	sprintf(name, "ec%u", ec_device_count);
	124	dev_dir = debugfs_create_dir(name, acpi_ec_debugfs_dir);
	125	if (!dev_dir) {
500de3dd TR	126	if (ec_device_count != 0)
500de3dd TR	127	goto error;
1195a098 TR	128	return -ENOMEM;
	129	}
	130
3522f867	131	if (!debugfs_create_x32("gpe", 0444, dev_dir, &first_ec->gpe))
500de3dd TR	132	goto error;
500de3dd TR	133	if (!debugfs_create_bool("use_global_lock", 0444, dev_dir,
6e58f752	134	&first_ec->global_lock))
500de3dd TR	135	goto error;
	136
	137	if (write_support)
	138	mode = 0600;
	139	if (!debugfs_create_file("io", mode, dev_dir, ec, &acpi_ec_io_ops))
	140	goto error;
	141
1195a098	142	return 0;
500de3dd TR	143
	144	error:
	145	debugfs_remove_recursive(acpi_ec_debugfs_dir);
	146	return -ENOMEM;
1195a098 TR	147	}
	148
	149	static int __init acpi_ec_sys_init(void)
	150	{
	151	int err = 0;
	152	if (first_ec)
	153	err = acpi_ec_add_debugfs(first_ec, 0);
	154	else
	155	err = -ENODEV;
	156	return err;
	157	}
	158
	159	static void __exit acpi_ec_sys_exit(void)
	160	{
	161	debugfs_remove_recursive(acpi_ec_debugfs_dir);
	162	}
	163
	164	module_init(acpi_ec_sys_init);
	165	module_exit(acpi_ec_sys_exit);