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path: root/drivers/acpi/ec_sys.c
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Diffstat (limited to 'drivers/acpi/ec_sys.c')
-rw-r--r--drivers/acpi/ec_sys.c162
1 files changed, 162 insertions, 0 deletions
diff --git a/drivers/acpi/ec_sys.c b/drivers/acpi/ec_sys.c
new file mode 100644
index 000000000..b4c216bab
--- /dev/null
+++ b/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);