Linux Audio

Check our new training course

Linux kernel drivers training

Mar 31-Apr 9, 2025, special US time zones
Register
Loading...
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * ec_sys.c
  4 *
  5 * Copyright (C) 2010 SUSE Products GmbH/Novell
  6 * Author:
  7 *      Thomas Renninger <trenn@suse.de>
  8 */
  9
 10#include <linux/kernel.h>
 11#include <linux/acpi.h>
 12#include <linux/debugfs.h>
 13#include <linux/module.h>
 14#include <linux/uaccess.h>
 15#include "internal.h"
 16
 17MODULE_AUTHOR("Thomas Renninger <trenn@suse.de>");
 18MODULE_DESCRIPTION("ACPI EC sysfs access driver");
 19MODULE_LICENSE("GPL");
 20
 21static bool write_support;
 22module_param_hw(write_support, bool, other, 0644);
 23MODULE_PARM_DESC(write_support, "Dangerous, reboot and removal of battery may "
 24		 "be needed.");
 25
 26#define EC_SPACE_SIZE 256
 27
 28static struct dentry *acpi_ec_debugfs_dir;
 29
 30static 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;
 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) {
 49		u8 byte_read;
 50		err = ec_read(*off, &byte_read);
 51		if (err)
 52			return err;
 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		}
 58		*off += 1;
 59		size--;
 60	}
 61	return count;
 62}
 63
 64static 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;
 73	int err = 0;
 74
 75	if (!write_support)
 76		return -EINVAL;
 77
 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) {
 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		}
 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
102static const struct file_operations acpi_ec_io_ops = {
103	.owner = THIS_MODULE,
104	.open  = simple_open,
105	.read  = acpi_ec_read_io,
106	.write = acpi_ec_write_io,
107	.llseek = default_llseek,
108};
109
110static void acpi_ec_add_debugfs(struct acpi_ec *ec, unsigned int ec_device_count)
111{
112	struct dentry *dev_dir;
113	char name[64];
114	umode_t mode = 0400;
115
116	if (ec_device_count == 0)
117		acpi_ec_debugfs_dir = debugfs_create_dir("ec", NULL);
118
119	sprintf(name, "ec%u", ec_device_count);
120	dev_dir = debugfs_create_dir(name, acpi_ec_debugfs_dir);
121
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);
125
126	if (write_support)
127		mode = 0600;
128	debugfs_create_file("io", mode, dev_dir, ec, &acpi_ec_io_ops);
129}
130
131static int __init acpi_ec_sys_init(void)
132{
133	if (first_ec)
134		acpi_ec_add_debugfs(first_ec, 0);
135	return 0;
136}
137
138static void __exit acpi_ec_sys_exit(void)
139{
140	debugfs_remove_recursive(acpi_ec_debugfs_dir);
141}
142
143module_init(acpi_ec_sys_init);
144module_exit(acpi_ec_sys_exit);
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * ec_sys.c
  4 *
  5 * Copyright (C) 2010 SUSE Products GmbH/Novell
  6 * Author:
  7 *      Thomas Renninger <trenn@suse.de>
  8 */
  9
 10#include <linux/kernel.h>
 11#include <linux/acpi.h>
 12#include <linux/debugfs.h>
 13#include <linux/module.h>
 14#include <linux/uaccess.h>
 15#include "internal.h"
 16
 17MODULE_AUTHOR("Thomas Renninger <trenn@suse.de>");
 18MODULE_DESCRIPTION("ACPI EC sysfs access driver");
 19MODULE_LICENSE("GPL");
 20
 21static bool write_support;
 22module_param(write_support, bool, 0644);
 23MODULE_PARM_DESC(write_support, "Dangerous, reboot and removal of battery may "
 24		 "be needed.");
 25
 26#define EC_SPACE_SIZE 256
 27
 28static struct dentry *acpi_ec_debugfs_dir;
 29
 30static 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;
 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) {
 49		u8 byte_read;
 50		err = ec_read(*off, &byte_read);
 51		if (err)
 52			return err;
 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		}
 58		*off += 1;
 59		size--;
 60	}
 61	return count;
 62}
 63
 64static 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;
 73	int err = 0;
 74
 75	if (!write_support)
 76		return -EINVAL;
 77
 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) {
 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		}
 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
102static const struct file_operations acpi_ec_io_ops = {
103	.owner = THIS_MODULE,
104	.open  = simple_open,
105	.read  = acpi_ec_read_io,
106	.write = acpi_ec_write_io,
107	.llseek = default_llseek,
108};
109
110static void acpi_ec_add_debugfs(struct acpi_ec *ec, unsigned int ec_device_count)
111{
112	struct dentry *dev_dir;
113	char name[64];
114	umode_t mode = 0400;
115
116	if (ec_device_count == 0)
117		acpi_ec_debugfs_dir = debugfs_create_dir("ec", NULL);
118
119	sprintf(name, "ec%u", ec_device_count);
120	dev_dir = debugfs_create_dir(name, acpi_ec_debugfs_dir);
121
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);
125
126	if (write_support)
127		mode = 0600;
128	debugfs_create_file("io", mode, dev_dir, ec, &acpi_ec_io_ops);
129}
130
131static int __init acpi_ec_sys_init(void)
132{
133	if (first_ec)
134		acpi_ec_add_debugfs(first_ec, 0);
135	return 0;
136}
137
138static void __exit acpi_ec_sys_exit(void)
139{
140	debugfs_remove_recursive(acpi_ec_debugfs_dir);
141}
142
143module_init(acpi_ec_sys_init);
144module_exit(acpi_ec_sys_exit);