leds: Add driver for HP harddisk protection LEDs

HP notebooks contain accelerometer-based disk protection subsystem,
and LED that indicates hard disk is protected. This is driver for the
LED part.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

1 files changed, 156 insertions, 0 deletions

diff --git a/drivers/leds/leds-hp-disk.c b/drivers/leds/leds-hp-disk.c
new file mode 100644
index 000000000000..d636280198ab
--- /dev/null
+++ b/drivers/leds/leds-hp-disk.c
@@ -0,0 +1,156 @@
+/*
+ *  leds-hp-disk.c - driver for HP "hard disk protection" LED
+ *
+ *  Copyright (C) 2008 Pavel Machek
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/dmi.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/kthread.h>
+#include <linux/version.h>
+#include <linux/leds.h>
+#include <acpi/acpi_drivers.h>
+
+#define DRIVER_NAME     "leds-hp-disk"
+#define ACPI_MDPS_CLASS "led"
+
+/* For automatic insertion of the module */
+static struct acpi_device_id hpled_device_ids[] = {
+        {"HPQ0004", 0}, /* HP Mobile Data Protection System PNP */
+        {"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, hpled_device_ids);
+
+struct acpi_hpled {
+        struct acpi_device      *device;   /* The ACPI device */
+};
+
+static struct acpi_hpled adev;
+
+static acpi_status hpled_acpi_write(acpi_handle handle, int reg)
+{
+        unsigned long ret; /* Not used when writing */
+        union acpi_object in_obj[1];
+        struct acpi_object_list args = { 1, in_obj };
+
+        in_obj[0].type          = ACPI_TYPE_INTEGER;
+        in_obj[0].integer.value = reg;
+
+        return acpi_evaluate_integer(handle, "ALED", &args, &ret);
+}
+
+static void hpled_set(struct led_classdev *led_cdev,
+                               enum led_brightness value)
+{
+        hpled_acpi_write(adev.device->handle, !!value);
+}
+
+static struct led_classdev hpled_led = {
+        .name                   = "hp:red:hddprotection",
+        .default_trigger        = "heartbeat",
+        .brightness_set         = hpled_set,
+};
+
+#ifdef CONFIG_PM
+static int hpled_suspend(struct acpi_device *dev, pm_message_t state)
+{
+        led_classdev_suspend(&hpled_led);
+        return 0;
+}
+
+static int hpled_resume(struct acpi_device *dev)
+{
+        led_classdev_resume(&hpled_led);
+        return 0;
+}
+#else
+#define hpled_suspend NULL
+#define hpled_resume NULL
+#endif
+
+static int hpled_add(struct acpi_device *device)
+{
+        int ret;
+
+        if (!device)
+                return -EINVAL;
+
+        adev.device = device;
+        strcpy(acpi_device_name(device), DRIVER_NAME);
+        strcpy(acpi_device_class(device), ACPI_MDPS_CLASS);
+        acpi_driver_data(device) = &adev;
+
+        ret = led_classdev_register(NULL, &hpled_led);
+        return ret;
+}
+
+static int hpled_remove(struct acpi_device *device, int type)
+{
+        if (!device)
+                return -EINVAL;
+
+        led_classdev_unregister(&hpled_led);
+        return 0;
+}
+
+
+
+static struct acpi_driver leds_hp_driver = {
+        .name  = DRIVER_NAME,
+        .class = ACPI_MDPS_CLASS,
+        .ids   = hpled_device_ids,
+        .ops = {
+                .add     = hpled_add,
+                .remove  = hpled_remove,
+                .suspend = hpled_suspend,
+                .resume  = hpled_resume,
+        }
+};
+
+static int __init hpled_init_module(void)
+{
+        int ret;
+
+        if (acpi_disabled)
+                return -ENODEV;
+
+        ret = acpi_bus_register_driver(&leds_hp_driver);
+        if (ret < 0)
+                return ret;
+
+        printk(KERN_INFO DRIVER_NAME " driver loaded.\n");
+
+        return 0;
+}
+
+static void __exit hpled_exit_module(void)
+{
+        acpi_bus_unregister_driver(&leds_hp_driver);
+}
+
+MODULE_DESCRIPTION("Driver for HP disk protection LED");
+MODULE_AUTHOR("Pavel Machek <pavel@suse.cz>");
+MODULE_LICENSE("GPL");
+
+module_init(hpled_init_module);
+module_exit(hpled_exit_module);