[linux-2.6-block.git] / drivers / acpi / ec_sys.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * ec_sys.c
 *
 * Copyright (C) 2010 SUSE Products GmbH/Novell
 * Author:
 *      Thomas Renninger <trenn@suse.de>
 */

#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);
Commit	Line	Data
7a338472	1	// SPDX-License-Identifier: GPL-2.0-only
9827886d TR	2	/*
	3	* ec_sys.c
	4	*
	5	* Copyright (C) 2010 SUSE Products GmbH/Novell
	6	* Author:
	7	* Thomas Renninger <trenn@suse.de>
9827886d TR	8	*/
9827886d TR	9
1195a098 TR	10	#include <linux/kernel.h>
	11	#include <linux/acpi.h>
	12	#include <linux/debugfs.h>
cc4b859c	13	#include <linux/module.h>
ecde3003	14	#include <linux/uaccess.h>
1195a098 TR	15	#include "internal.h"
	16
	17	MODULE_AUTHOR("Thomas Renninger <trenn@suse.de>");
	18	MODULE_DESCRIPTION("ACPI EC sysfs access driver");
	19	MODULE_LICENSE("GPL");
	20
500de3dd TR	21	static bool write_support;
	22	module_param(write_support, bool, 0644);
	23	MODULE_PARM_DESC(write_support, "Dangerous, reboot and removal of battery may "
	24	"be needed.");
	25
9827886d TR	26	#define EC_SPACE_SIZE 256
9827886d TR	27
1195a098 TR	28	static struct dentry *acpi_ec_debugfs_dir;
1195a098 TR	29
9827886d TR	30	static ssize_t acpi_ec_read_io(struct file f, char __user buf,
	31	size_t count, loff_t *off)
	32	{
	33	/* Use this if support reading/writing multiple ECs exists in ec.c:
	34	* struct acpi_ec ec = ((struct seq_file )f->private_data)->private;
	35	*/
	36	unsigned int size = EC_SPACE_SIZE;
9827886d TR	37	loff_t init_off = *off;
	38	int err = 0;
	39
	40	if (*off >= size)
	41	return 0;
	42	if (*off + count >= size) {
	43	size -= *off;
	44	count = size;
	45	} else
	46	size = count;
	47
	48	while (size) {
ecde3003 VK	49	u8 byte_read;
ecde3003 VK	50	err = ec_read(*off, &byte_read);
9827886d TR	51	if (err)
9827886d TR	52	return err;
ecde3003 VK	53	if (put_user(byte_read, buf + *off - init_off)) {
	54	if (*off - init_off)
	55	return off - init_off; / partial read */
	56	return -EFAULT;
	57	}
9827886d TR	58	*off += 1;
	59	size--;
	60	}
	61	return count;
	62	}
	63
	64	static ssize_t acpi_ec_write_io(struct file f, const char __user buf,
	65	size_t count, loff_t *off)
	66	{
	67	/* Use this if support reading/writing multiple ECs exists in ec.c:
	68	* struct acpi_ec ec = ((struct seq_file )f->private_data)->private;
	69	*/
	70
	71	unsigned int size = count;
	72	loff_t init_off = *off;
9827886d TR	73	int err = 0;
9827886d TR	74
1b6e75ee OD	75	if (!write_support)
	76	return -EINVAL;
	77
9827886d TR	78	if (*off >= EC_SPACE_SIZE)
	79	return 0;
	80	if (*off + count >= EC_SPACE_SIZE) {
	81	size = EC_SPACE_SIZE - *off;
	82	count = size;
	83	}
	84
	85	while (size) {
ecde3003 VK	86	u8 byte_write;
	87	if (get_user(byte_write, buf + *off - init_off)) {
	88	if (*off - init_off)
	89	return off - init_off; / partial write */
	90	return -EFAULT;
	91	}
9827886d TR	92	err = ec_write(*off, byte_write);
	93	if (err)
	94	return err;
	95
	96	*off += 1;
	97	size--;
	98	}
	99	return count;
	100	}
	101
9c8b04be	102	static const struct file_operations acpi_ec_io_ops = {
9827886d	103	.owner = THIS_MODULE,
234e3405	104	.open = simple_open,
9827886d TR	105	.read = acpi_ec_read_io,
9827886d TR	106	.write = acpi_ec_write_io,
6038f373	107	.llseek = default_llseek,
9827886d TR	108	};
9827886d TR	109
9ec6dbfb	110	static void acpi_ec_add_debugfs(struct acpi_ec *ec, unsigned int ec_device_count)
1195a098 TR	111	{
	112	struct dentry *dev_dir;
	113	char name[64];
f4ae40a6	114	umode_t mode = 0400;
500de3dd	115
9ec6dbfb	116	if (ec_device_count == 0)
1195a098	117	acpi_ec_debugfs_dir = debugfs_create_dir("ec", NULL);
1195a098 TR	118
	119	sprintf(name, "ec%u", ec_device_count);
	120	dev_dir = debugfs_create_dir(name, acpi_ec_debugfs_dir);
1195a098	121
9ec6dbfb GKH	122	debugfs_create_x32("gpe", 0444, dev_dir, &first_ec->gpe);
	123	debugfs_create_bool("use_global_lock", 0444, dev_dir,
	124	&first_ec->global_lock);
500de3dd TR	125
	126	if (write_support)
	127	mode = 0600;
9ec6dbfb	128	debugfs_create_file("io", mode, dev_dir, ec, &acpi_ec_io_ops);
1195a098 TR	129	}
	130
	131	static int __init acpi_ec_sys_init(void)
	132	{
1195a098	133	if (first_ec)
9ec6dbfb GKH	134	acpi_ec_add_debugfs(first_ec, 0);
9ec6dbfb GKH	135	return 0;
1195a098 TR	136	}
	137
	138	static void __exit acpi_ec_sys_exit(void)
	139	{
	140	debugfs_remove_recursive(acpi_ec_debugfs_dir);
	141	}
	142
	143	module_init(acpi_ec_sys_init);
	144	module_exit(acpi_ec_sys_exit);