[PATCH 3/8] [-mm] ACPI: add ACPI Fan sysfs interface

[Zhang Rui <rui.zhang@intel.com>]

From: Zhang Rui <rui.zhang@intel.com>

Add ACPI Fan device sysfs interface.

Attribute	Mode	Description
state		RW	Fan state.
			0: Fan is in D0 state(on).
			3: Fan is in D3 state(off).

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/acpi/fan.c |   98 +++++++++++++++++++++++++++++++++++++++++++++++------
 1 files changed, 87 insertions(+), 11 deletions(-)

Index: linux-2.6.21-rc3-mm2/drivers/acpi/fan.c
===================================================================
--- linux-2.6.21-rc3-mm2.orig/drivers/acpi/fan.c	2007-03-16 10:08:06.000000000 +0800
+++ linux-2.6.21-rc3-mm2/drivers/acpi/fan.c	2007-03-16 10:20:02.000000000 +0800
@@ -67,8 +67,57 @@ struct acpi_fan {
 };
 
 /* --------------------------------------------------------------------------
+                              FS Interface (/sys)
+   -------------------------------------------------------------------------- */
+
+static ssize_t
+acpi_fan_state_show(struct acpi_device *dev, char *buf)
+{
+	struct acpi_fan *fan = acpi_driver_data(dev);
+	int state = 0;
+	ssize_t result = 0;
+
+	if (!fan)
+		return -EINVAL;
+
+	result = acpi_bus_get_power(fan->device->handle, &state);
+	if (!result)
+		result = sprintf(buf, "%u\n", state);
+
+	return result;
+}
+
+static ssize_t
+acpi_fan_state_store(struct acpi_device *dev, const char *buf, size_t count)
+{
+	struct acpi_fan *fan = acpi_driver_data(dev);
+	ssize_t result;
+	char * end;
+	int state;
+
+	if (!fan)
+		return -EINVAL;
+
+	state = simple_strtoul(buf, &end, 0);
+	if (*end == '\0')
+		return -EINVAL;
+
+	result = acpi_bus_set_power(fan->device->handle, state);
+	if (!result)
+		result = count;
+
+	return result;
+}
+static ACPI_DEVICE_ATTR(state, 0644, acpi_fan_state_show, acpi_fan_state_store);
+
+static struct device_attribute* fan_attr[] = {
+	GET_DEV_ATTR(state),
+	NULL,
+};
+/* --------------------------------------------------------------------------
                               FS Interface (/proc)
    -------------------------------------------------------------------------- */
+#ifdef CONFIG_ACPI_PROCFS
 
 static struct proc_dir_entry *acpi_fan_dir;
 
@@ -128,7 +177,7 @@ static const struct file_operations acpi
 	.owner = THIS_MODULE,
 };
 
-static int acpi_fan_add_fs(struct acpi_device *device)
+static int acpi_fan_add_procfs(struct acpi_device *device)
 {
 	struct proc_dir_entry *entry = NULL;
 
@@ -159,7 +208,7 @@ static int acpi_fan_add_fs(struct acpi_d
 	return 0;
 }
 
-static int acpi_fan_remove_fs(struct acpi_device *device)
+static int acpi_fan_remove_procfs(struct acpi_device *device)
 {
 
 	if (acpi_device_dir(device)) {
@@ -171,6 +220,25 @@ static int acpi_fan_remove_fs(struct acp
 	return 0;
 }
 
+static int acpi_fan_procfs_init(void)
+{
+	acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
+	if (!acpi_fan_dir)
+		return -ENODEV;
+	acpi_fan_dir->owner = THIS_MODULE;
+
+	return 0;
+}
+
+static int acpi_fan_procfs_exit(void)
+{
+	remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
+
+	return 0;
+}
+#else
+DECLARE_ACPI_DEVICE_PROCFS(fan);
+#endif
 /* --------------------------------------------------------------------------
                                  Driver Interface
    -------------------------------------------------------------------------- */
@@ -204,18 +272,25 @@ static int acpi_fan_add(struct acpi_devi
 	acpi_bus_set_power(device->handle, state);
 	device->flags.force_power_state = 0;
 
-	result = acpi_fan_add_fs(device);
+	result = acpi_device_add_sysfs(device, fan_attr);
 	if (result)
 		goto end;
 
+	result = acpi_fan_add_procfs(device);
+	if (result)
+		goto procfs_error;
+
 	printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 	       acpi_device_name(device), acpi_device_bid(device),
 	       !device->power.state ? "on" : "off");
 
+	goto end;
+
+      procfs_error:
+	acpi_device_remove_sysfs(device,fan_attr);
       end:
 	if (result)
 		kfree(fan);
-
 	return result;
 }
 
@@ -229,7 +304,9 @@ static int acpi_fan_remove(struct acpi_d
 
 	fan = acpi_driver_data(device);
 
-	acpi_fan_remove_fs(device);
+	acpi_fan_remove_procfs(device);
+
+	acpi_device_remove_sysfs(device, fan_attr);
 
 	kfree(fan);
 
@@ -272,15 +349,14 @@ static int __init acpi_fan_init(void)
 {
 	int result = 0;
 
-
-	acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
-	if (!acpi_fan_dir)
+	result = acpi_fan_procfs_init();
+	if (result)
 		return -ENODEV;
-	acpi_fan_dir->owner = THIS_MODULE;
 
+	acpi_fan_driver.owner = THIS_MODULE;
 	result = acpi_bus_register_driver(&acpi_fan_driver);
 	if (result < 0) {
-		remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
+		acpi_fan_procfs_exit();
 		return -ENODEV;
 	}
 
@@ -292,7 +368,7 @@ static void __exit acpi_fan_exit(void)
 
 	acpi_bus_unregister_driver(&acpi_fan_driver);
 
-	remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
+	acpi_fan_procfs_exit();
 
 	return;
 }