Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / acpi / ec_sys.c

diff --git a/kernel/drivers/acpi/ec_sys.c b/kernel/drivers/acpi/ec_sys.c
new file mode 100644 (file)
index 0000000..b4c216b
--- /dev/null
+++ b/kernel/drivers/acpi/ec_sys.c
@@ -0,0 +1,162 @@
+/*
+ * 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 (*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, (u32 *)&first_ec->gpe))
+               goto error;
+       if (!debugfs_create_bool("use_global_lock", 0444, dev_dir,
+                                (u32 *)&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);