acer-wmi: Add driver for newer Acer laptops

This is a driver for newer Acer (and Wistron) laptops. It adds wireless
radio and bluetooth control, and on some laptops, exposes the mail LED and
LCD backlight.

v1:

* Initial release

v2:

* Replace left over ACPI references with WMI
* Add GUID based autoloading (depends on future work to WMI)
* Add DMI based autoloading (backup solution until WMI sysfs/ class
  work is available)
* Checkpatch fixes

v3:

* Add new EC quirks for Aspire 3100 & 5100, and Extensa 5220

v4:

* Simplified internal handling of WMID and AMW0 devices
* Add autodetection for bluetooth and maximum brightness on AMW0 V2 and
  WMID laptops.

v5:

* Add EC quirk for Medion MD 98000
* Add autodetection for AMW0, and mail LED on AMW0 and AMW0 V2.
* Improve error handling
* Fix AMW0 V2 bluetooth and wireless, by using both WMID and AMW0 methods
  to ensure that the correct value is always set.

v6:

* Fix 'use before initialisation' bug with quirks.

v7

* Fix bug on AMW0 where acer-wmi would exit if a mail LED was not
  detected.
* Add Acer Aspire 9110 mail LED support
* Fix section mismatch warnings

Signed-off-by: Carlos Corbacho <carlos@strangeworlds.co.uk>
CC: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 1109 insertions, 0 deletions

diff --git a/drivers/misc/acer-wmi.c b/drivers/misc/acer-wmi.c
new file mode 100644
index 000000000000..a4d677504250
--- /dev/null
+++ b/drivers/misc/acer-wmi.c
@@ -0,0 +1,1109 @@
+/*
+ *  Acer WMI Laptop Extras
+ *
+ *  Copyright (C) 2007-2008     Carlos Corbacho <carlos@strangeworlds.co.uk>
+ *
+ *  Based on acer_acpi:
+ *    Copyright (C) 2005-2007   E.M. Smith
+ *    Copyright (C) 2007-2008   Carlos Corbacho <cathectic@gmail.com>
+ *
+ *  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
+ */
+
+#define ACER_WMI_VERSION        "0.1"
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/dmi.h>
+#include <linux/backlight.h>
+#include <linux/leds.h>
+#include <linux/platform_device.h>
+#include <linux/acpi.h>
+#include <linux/i8042.h>
+
+#include <acpi/acpi_drivers.h>
+
+MODULE_AUTHOR("Carlos Corbacho");
+MODULE_DESCRIPTION("Acer Laptop WMI Extras Driver");
+MODULE_LICENSE("GPL");
+
+#define ACER_LOGPREFIX "acer-wmi: "
+#define ACER_ERR KERN_ERR ACER_LOGPREFIX
+#define ACER_NOTICE KERN_NOTICE ACER_LOGPREFIX
+#define ACER_INFO KERN_INFO ACER_LOGPREFIX
+
+/*
+ * The following defines quirks to get some specific functions to work
+ * which are known to not be supported over ACPI-WMI (such as the mail LED
+ * on WMID based Acer's)
+ */
+struct acer_quirks {
+        const char *vendor;
+        const char *model;
+        u16 quirks;
+};
+
+/*
+ * Magic Number
+ * Meaning is unknown - this number is required for writing to ACPI for AMW0
+ * (it's also used in acerhk when directly accessing the BIOS)
+ */
+#define ACER_AMW0_WRITE 0x9610
+
+/*
+ * Bit masks for the AMW0 interface
+ */
+#define ACER_AMW0_WIRELESS_MASK  0x35
+#define ACER_AMW0_BLUETOOTH_MASK 0x34
+#define ACER_AMW0_MAILLED_MASK   0x31
+
+/*
+ * Method IDs for WMID interface
+ */
+#define ACER_WMID_GET_WIRELESS_METHODID         1
+#define ACER_WMID_GET_BLUETOOTH_METHODID        2
+#define ACER_WMID_GET_BRIGHTNESS_METHODID       3
+#define ACER_WMID_SET_WIRELESS_METHODID         4
+#define ACER_WMID_SET_BLUETOOTH_METHODID        5
+#define ACER_WMID_SET_BRIGHTNESS_METHODID       6
+#define ACER_WMID_GET_THREEG_METHODID           10
+#define ACER_WMID_SET_THREEG_METHODID           11
+
+/*
+ * Acer ACPI method GUIDs
+ */
+#define AMW0_GUID1              "67C3371D-95A3-4C37-BB61-DD47B491DAAB"
+#define WMID_GUID1              "6AF4F258-B401-42fd-BE91-3D4AC2D7C0D3"
+#define WMID_GUID2              "95764E09-FB56-4e83-B31A-37761F60994A"
+
+MODULE_ALIAS("wmi:67C3371D-95A3-4C37-BB61-DD47B491DAAB");
+MODULE_ALIAS("wmi:6AF4F258-B401-42fd-BE91-3D4AC2D7C0D3");
+
+/* Temporary workaround until the WMI sysfs interface goes in */
+MODULE_ALIAS("dmi:*:*Acer*:*:");
+
+/*
+ * Interface capability flags
+ */
+#define ACER_CAP_MAILLED                (1<<0)
+#define ACER_CAP_WIRELESS               (1<<1)
+#define ACER_CAP_BLUETOOTH              (1<<2)
+#define ACER_CAP_BRIGHTNESS             (1<<3)
+#define ACER_CAP_THREEG                 (1<<4)
+#define ACER_CAP_ANY                    (0xFFFFFFFF)
+
+/*
+ * Interface type flags
+ */
+enum interface_flags {
+        ACER_AMW0,
+        ACER_AMW0_V2,
+        ACER_WMID,
+};
+
+#define ACER_DEFAULT_WIRELESS  0
+#define ACER_DEFAULT_BLUETOOTH 0
+#define ACER_DEFAULT_MAILLED   0
+#define ACER_DEFAULT_THREEG    0
+
+static int max_brightness = 0xF;
+
+static int wireless = -1;
+static int bluetooth = -1;
+static int mailled = -1;
+static int brightness = -1;
+static int threeg = -1;
+static int force_series;
+
+module_param(mailled, int, 0444);
+module_param(wireless, int, 0444);
+module_param(bluetooth, int, 0444);
+module_param(brightness, int, 0444);
+module_param(threeg, int, 0444);
+module_param(force_series, int, 0444);
+MODULE_PARM_DESC(wireless, "Set initial state of Wireless hardware");
+MODULE_PARM_DESC(bluetooth, "Set initial state of Bluetooth hardware");
+MODULE_PARM_DESC(mailled, "Set initial state of Mail LED");
+MODULE_PARM_DESC(brightness, "Set initial LCD backlight brightness");
+MODULE_PARM_DESC(threeg, "Set initial state of 3G hardware");
+MODULE_PARM_DESC(force_series, "Force a different laptop series");
+
+struct acer_data {
+        int mailled;
+        int wireless;
+        int bluetooth;
+        int threeg;
+        int brightness;
+};
+
+/* Each low-level interface must define at least some of the following */
+struct wmi_interface {
+        /* The WMI device type */
+        u32 type;
+
+        /* The capabilities this interface provides */
+        u32 capability;
+
+        /* Private data for the current interface */
+        struct acer_data data;
+};
+
+/* The static interface pointer, points to the currently detected interface */
+static struct wmi_interface *interface;
+
+/*
+ * Embedded Controller quirks
+ * Some laptops require us to directly access the EC to either enable or query
+ * features that are not available through WMI.
+ */
+
+struct quirk_entry {
+        u8 wireless;
+        u8 mailled;
+        u8 brightness;
+        u8 bluetooth;
+};
+
+static struct quirk_entry *quirks;
+
+static void set_quirks(void)
+{
+        if (quirks->mailled)
+                interface->capability |= ACER_CAP_MAILLED;
+
+        if (quirks->brightness)
+                interface->capability |= ACER_CAP_BRIGHTNESS;
+}
+
+static int dmi_matched(const struct dmi_system_id *dmi)
+{
+        quirks = dmi->driver_data;
+        return 0;
+}
+
+static struct quirk_entry quirk_unknown = {
+};
+
+static struct quirk_entry quirk_acer_travelmate_2490 = {
+        .mailled = 1,
+};
+
+/* This AMW0 laptop has no bluetooth */
+static struct quirk_entry quirk_medion_md_98300 = {
+        .wireless = 1,
+};
+
+static struct dmi_system_id acer_quirks[] = {
+        {
+                .callback = dmi_matched,
+                .ident = "Acer Aspire 3100",
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 3100"),
+                },
+                .driver_data = &quirk_acer_travelmate_2490,
+        },
+        {
+                .callback = dmi_matched,
+                .ident = "Acer Aspire 5100",
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5100"),
+                },
+                .driver_data = &quirk_acer_travelmate_2490,
+        },
+        {
+                .callback = dmi_matched,
+                .ident = "Acer Aspire 5630",
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5630"),
+                },
+                .driver_data = &quirk_acer_travelmate_2490,
+        },
+        {
+                .callback = dmi_matched,
+                .ident = "Acer Aspire 5650",
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5650"),
+                },
+                .driver_data = &quirk_acer_travelmate_2490,
+        },
+        {
+                .callback = dmi_matched,
+                .ident = "Acer Aspire 5680",
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5680"),
+                },
+                .driver_data = &quirk_acer_travelmate_2490,
+        },
+        {
+                .callback = dmi_matched,
+                .ident = "Acer Aspire 9110",
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 9110"),
+                },
+                .driver_data = &quirk_acer_travelmate_2490,
+        },
+        {
+                .callback = dmi_matched,
+                .ident = "Acer TravelMate 2490",
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 2490"),
+                },
+                .driver_data = &quirk_acer_travelmate_2490,
+        },
+        {
+                .callback = dmi_matched,
+                .ident = "Medion MD 98300",
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "MEDION"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "WAM2030"),
+                },
+                .driver_data = &quirk_medion_md_98300,
+        },
+        {}
+};
+
+/* Find which quirks are needed for a particular vendor/ model pair */
+static void find_quirks(void)
+{
+        if (!force_series) {
+                dmi_check_system(acer_quirks);
+        } else if (force_series == 2490) {
+                quirks = &quirk_acer_travelmate_2490;
+        }
+
+        if (quirks == NULL)
+                quirks = &quirk_unknown;
+
+        set_quirks();
+}
+
+/*
+ * General interface convenience methods
+ */
+
+static bool has_cap(u32 cap)
+{
+        if ((interface->capability & cap) != 0)
+                return 1;
+
+        return 0;
+}
+
+/*
+ * AMW0 (V1) interface
+ */
+struct wmab_args {
+        u32 eax;
+        u32 ebx;
+        u32 ecx;
+        u32 edx;
+};
+
+struct wmab_ret {
+        u32 eax;
+        u32 ebx;
+        u32 ecx;
+        u32 edx;
+        u32 eex;
+};
+
+static acpi_status wmab_execute(struct wmab_args *regbuf,
+struct acpi_buffer *result)
+{
+        struct acpi_buffer input;
+        acpi_status status;
+        input.length = sizeof(struct wmab_args);
+        input.pointer = (u8 *)regbuf;
+
+        status = wmi_evaluate_method(AMW0_GUID1, 1, 1, &input, result);
+
+        return status;
+}
+
+static acpi_status AMW0_get_u32(u32 *value, u32 cap,
+struct wmi_interface *iface)
+{
+        int err;
+        u8 result;
+
+        switch (cap) {
+        case ACER_CAP_MAILLED:
+                switch (quirks->mailled) {
+                default:
+                        err = ec_read(0xA, &result);
+                        if (err)
+                                return AE_ERROR;
+                        *value = (result >> 7) & 0x1;
+                        return AE_OK;
+                }
+                break;
+        case ACER_CAP_WIRELESS:
+                switch (quirks->wireless) {
+                case 1:
+                        err = ec_read(0x7B, &result);
+                        if (err)
+                                return AE_ERROR;
+                        *value = result & 0x1;
+                        return AE_OK;
+                default:
+                        err = ec_read(0xA, &result);
+                        if (err)
+                                return AE_ERROR;
+                        *value = (result >> 2) & 0x1;
+                        return AE_OK;
+                }
+                break;
+        case ACER_CAP_BLUETOOTH:
+                switch (quirks->bluetooth) {
+                default:
+                        err = ec_read(0xA, &result);
+                        if (err)
+                                return AE_ERROR;
+                        *value = (result >> 4) & 0x1;
+                        return AE_OK;
+                }
+                break;
+        case ACER_CAP_BRIGHTNESS:
+                switch (quirks->brightness) {
+                default:
+                        err = ec_read(0x83, &result);
+                        if (err)
+                                return AE_ERROR;
+                        *value = result;
+                        return AE_OK;
+                }
+                break;
+        default:
+                return AE_BAD_ADDRESS;
+        }
+        return AE_OK;
+}
+
+static acpi_status AMW0_set_u32(u32 value, u32 cap, struct wmi_interface *iface)
+{
+        struct wmab_args args;
+
+        args.eax = ACER_AMW0_WRITE;
+        args.ebx = value ? (1<<8) : 0;
+        args.ecx = args.edx = 0;
+
+        switch (cap) {
+        case ACER_CAP_MAILLED:
+                if (value > 1)
+                        return AE_BAD_PARAMETER;
+                args.ebx |= ACER_AMW0_MAILLED_MASK;
+                break;
+        case ACER_CAP_WIRELESS:
+                if (value > 1)
+                        return AE_BAD_PARAMETER;
+                args.ebx |= ACER_AMW0_WIRELESS_MASK;
+                break;
+        case ACER_CAP_BLUETOOTH:
+                if (value > 1)
+                        return AE_BAD_PARAMETER;
+                args.ebx |= ACER_AMW0_BLUETOOTH_MASK;
+                break;
+        case ACER_CAP_BRIGHTNESS:
+                if (value > max_brightness)
+                        return AE_BAD_PARAMETER;
+                switch (quirks->brightness) {
+                case 1:
+                        return ec_write(0x83, value);
+                default:
+                        return AE_BAD_ADDRESS;
+                break;
+                }
+        default:
+                return AE_BAD_ADDRESS;
+        }
+
+        /* Actually do the set */
+        return wmab_execute(&args, NULL);
+}
+
+static acpi_status AMW0_find_mailled(void)
+{
+        struct wmab_args args;
+        struct wmab_ret ret;
+        acpi_status status = AE_OK;
+        struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
+        union acpi_object *obj;
+
+        args.eax = 0x86;
+        args.ebx = args.ecx = args.edx = 0;
+
+        status = wmab_execute(&args, &out);
+        if (ACPI_FAILURE(status))
+                return status;
+
+        obj = (union acpi_object *) out.pointer;
+        if (obj && obj->type == ACPI_TYPE_BUFFER &&
+        obj->buffer.length == sizeof(struct wmab_ret)) {
+                ret = *((struct wmab_ret *) obj->buffer.pointer);
+        } else {
+                return AE_ERROR;
+        }
+
+        if (ret.eex & 0x1)
+                interface->capability |= ACER_CAP_MAILLED;
+
+        kfree(out.pointer);
+
+        return AE_OK;
+}
+
+static acpi_status AMW0_set_capabilities(void)
+{
+        struct wmab_args args;
+        struct wmab_ret ret;
+        acpi_status status = AE_OK;
+        struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
+        union acpi_object *obj;
+
+        args.eax = ACER_AMW0_WRITE;
+        args.ecx = args.edx = 0;
+
+        args.ebx = 0xa2 << 8;
+        args.ebx |= ACER_AMW0_WIRELESS_MASK;
+
+        status = wmab_execute(&args, &out);
+        if (ACPI_FAILURE(status))
+                return status;
+
+        obj = (union acpi_object *) out.pointer;
+        if (obj && obj->type == ACPI_TYPE_BUFFER &&
+        obj->buffer.length == sizeof(struct wmab_ret)) {
+                ret = *((struct wmab_ret *) obj->buffer.pointer);
+        } else {
+                return AE_ERROR;
+        }
+
+        if (ret.eax & 0x1)
+                interface->capability |= ACER_CAP_WIRELESS;
+
+        args.ebx = 2 << 8;
+        args.ebx |= ACER_AMW0_BLUETOOTH_MASK;
+
+        status = wmab_execute(&args, &out);
+        if (ACPI_FAILURE(status))
+                return status;
+
+        obj = (union acpi_object *) out.pointer;
+        if (obj && obj->type == ACPI_TYPE_BUFFER
+        && obj->buffer.length == sizeof(struct wmab_ret)) {
+                ret = *((struct wmab_ret *) obj->buffer.pointer);
+        } else {
+                return AE_ERROR;
+        }
+
+        if (ret.eax & 0x1)
+                interface->capability |= ACER_CAP_BLUETOOTH;
+
+        kfree(out.pointer);
+
+        /*
+         * This appears to be safe to enable, since all Wistron based laptops
+         * appear to use the same EC register for brightness, even if they
+         * differ for wireless, etc
+         */
+        interface->capability |= ACER_CAP_BRIGHTNESS;
+
+        return AE_OK;
+}
+
+static struct wmi_interface AMW0_interface = {
+        .type = ACER_AMW0,
+};
+
+static struct wmi_interface AMW0_V2_interface = {
+        .type = ACER_AMW0_V2,
+};
+
+/*
+ * New interface (The WMID interface)
+ */
+static acpi_status
+WMI_execute_u32(u32 method_id, u32 in, u32 *out)
+{
+        struct acpi_buffer input = { (acpi_size) sizeof(u32), (void *)(&in) };
+        struct acpi_buffer result = { ACPI_ALLOCATE_BUFFER, NULL };
+        union acpi_object *obj;
+        u32 tmp;
+        acpi_status status;
+
+        status = wmi_evaluate_method(WMID_GUID1, 1, method_id, &input, &result);
+
+        if (ACPI_FAILURE(status))
+                return status;
+
+        obj = (union acpi_object *) result.pointer;
+        if (obj && obj->type == ACPI_TYPE_BUFFER &&
+                obj->buffer.length == sizeof(u32)) {
+                tmp = *((u32 *) obj->buffer.pointer);
+        } else {
+                tmp = 0;
+        }
+
+        if (out)
+                *out = tmp;
+
+        kfree(result.pointer);
+
+        return status;
+}
+
+static acpi_status WMID_get_u32(u32 *value, u32 cap,
+struct wmi_interface *iface)
+{
+        acpi_status status;
+        u8 tmp;
+        u32 result, method_id = 0;
+
+        switch (cap) {
+        case ACER_CAP_WIRELESS:
+                method_id = ACER_WMID_GET_WIRELESS_METHODID;
+                break;
+        case ACER_CAP_BLUETOOTH:
+                method_id = ACER_WMID_GET_BLUETOOTH_METHODID;
+                break;
+        case ACER_CAP_BRIGHTNESS:
+                method_id = ACER_WMID_GET_BRIGHTNESS_METHODID;
+                break;
+        case ACER_CAP_THREEG:
+                method_id = ACER_WMID_GET_THREEG_METHODID;
+                break;
+        case ACER_CAP_MAILLED:
+                if (quirks->mailled == 1) {
+                        ec_read(0x9f, &tmp);
+                        *value = tmp & 0x1;
+                        return 0;
+                }
+        default:
+                return AE_BAD_ADDRESS;
+        }
+        status = WMI_execute_u32(method_id, 0, &result);
+
+        if (ACPI_SUCCESS(status))
+                *value = (u8)result;
+
+        return status;
+}
+
+static acpi_status WMID_set_u32(u32 value, u32 cap, struct wmi_interface *iface)
+{
+        u32 method_id = 0;
+        char param;
+
+        switch (cap) {
+        case ACER_CAP_BRIGHTNESS:
+                if (value > max_brightness)
+                        return AE_BAD_PARAMETER;
+                method_id = ACER_WMID_SET_BRIGHTNESS_METHODID;
+                break;
+        case ACER_CAP_WIRELESS:
+                if (value > 1)
+                        return AE_BAD_PARAMETER;
+                method_id = ACER_WMID_SET_WIRELESS_METHODID;
+                break;
+        case ACER_CAP_BLUETOOTH:
+                if (value > 1)
+                        return AE_BAD_PARAMETER;
+                method_id = ACER_WMID_SET_BLUETOOTH_METHODID;
+                break;
+        case ACER_CAP_THREEG:
+                if (value > 1)
+                        return AE_BAD_PARAMETER;
+                method_id = ACER_WMID_SET_THREEG_METHODID;
+                break;
+        case ACER_CAP_MAILLED:
+                if (value > 1)
+                        return AE_BAD_PARAMETER;
+                if (quirks->mailled == 1) {
+                        param = value ? 0x92 : 0x93;
+                        i8042_command(&param, 0x1059);
+                        return 0;
+                }
+                break;
+        default:
+                return AE_BAD_ADDRESS;
+        }
+        return WMI_execute_u32(method_id, (u32)value, NULL);
+}
+
+static acpi_status WMID_set_capabilities(void)
+{
+        struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
+        union acpi_object *obj;
+        acpi_status status;
+        u32 devices;
+
+        status = wmi_query_block(WMID_GUID2, 1, &out);
+        if (ACPI_FAILURE(status))
+                return status;
+
+        obj = (union acpi_object *) out.pointer;
+        if (obj && obj->type == ACPI_TYPE_BUFFER &&
+                obj->buffer.length == sizeof(u32)) {
+                devices = *((u32 *) obj->buffer.pointer);
+        } else {
+                return AE_ERROR;
+        }
+
+        /* Not sure on the meaning of the relevant bits yet to detect these */
+        interface->capability |= ACER_CAP_WIRELESS;
+        interface->capability |= ACER_CAP_THREEG;
+
+        /* WMID always provides brightness methods */
+        interface->capability |= ACER_CAP_BRIGHTNESS;
+
+        if (devices & 0x10)
+                interface->capability |= ACER_CAP_BLUETOOTH;
+
+        if (!(devices & 0x20))
+                max_brightness = 0x9;
+
+        return status;
+}
+
+static struct wmi_interface wmid_interface = {
+        .type = ACER_WMID,
+};
+
+/*
+ * Generic Device (interface-independent)
+ */
+
+static acpi_status get_u32(u32 *value, u32 cap)
+{
+        acpi_status status = AE_BAD_ADDRESS;
+
+        switch (interface->type) {
+        case ACER_AMW0:
+                status = AMW0_get_u32(value, cap, interface);
+                break;
+        case ACER_AMW0_V2:
+                if (cap == ACER_CAP_MAILLED) {
+                        status = AMW0_get_u32(value, cap, interface);
+                        break;
+                }
+        case ACER_WMID:
+                status = WMID_get_u32(value, cap, interface);
+                break;
+        }
+
+        return status;
+}
+
+static acpi_status set_u32(u32 value, u32 cap)
+{
+        if (interface->capability & cap) {
+                switch (interface->type) {
+                case ACER_AMW0:
+                        return AMW0_set_u32(value, cap, interface);
+                case ACER_AMW0_V2:
+                case ACER_WMID:
+                        return WMID_set_u32(value, cap, interface);
+                default:
+                        return AE_BAD_PARAMETER;
+                }
+        }
+        return AE_BAD_PARAMETER;
+}
+
+static void __init acer_commandline_init(void)
+{
+        /*
+         * These will all fail silently if the value given is invalid, or the
+         * capability isn't available on the given interface
+         */
+        set_u32(mailled, ACER_CAP_MAILLED);
+        set_u32(wireless, ACER_CAP_WIRELESS);
+        set_u32(bluetooth, ACER_CAP_BLUETOOTH);
+        set_u32(threeg, ACER_CAP_THREEG);
+        set_u32(brightness, ACER_CAP_BRIGHTNESS);
+}
+
+/*
+ * LED device (Mail LED only, no other LEDs known yet)
+ */
+static void mail_led_set(struct led_classdev *led_cdev,
+enum led_brightness value)
+{
+        set_u32(value, ACER_CAP_MAILLED);
+}
+
+static struct led_classdev mail_led = {
+        .name = "acer-mail:green",
+        .brightness_set = mail_led_set,
+};
+
+static int __init acer_led_init(struct device *dev)
+{
+        return led_classdev_register(dev, &mail_led);
+}
+
+static void acer_led_exit(void)
+{
+        led_classdev_unregister(&mail_led);
+}
+
+/*
+ * Backlight device
+ */
+static struct backlight_device *acer_backlight_device;
+
+static int read_brightness(struct backlight_device *bd)
+{
+        u32 value;
+        get_u32(&value, ACER_CAP_BRIGHTNESS);
+        return value;
+}
+
+static int update_bl_status(struct backlight_device *bd)
+{
+        set_u32(bd->props.brightness, ACER_CAP_BRIGHTNESS);
+        return 0;
+}
+
+static struct backlight_ops acer_bl_ops = {
+        .get_brightness = read_brightness,
+        .update_status = update_bl_status,
+};
+
+static int __init acer_backlight_init(struct device *dev)
+{
+        struct backlight_device *bd;
+
+        bd = backlight_device_register("acer-wmi", dev, NULL, &acer_bl_ops);
+        if (IS_ERR(bd)) {
+                printk(ACER_ERR "Could not register Acer backlight device\n");
+                acer_backlight_device = NULL;
+                return PTR_ERR(bd);
+        }
+
+        acer_backlight_device = bd;
+
+        bd->props.max_brightness = max_brightness;
+        bd->props.brightness = read_brightness(NULL);
+        backlight_update_status(bd);
+        return 0;
+}
+
+static void __exit acer_backlight_exit(void)
+{
+        backlight_device_unregister(acer_backlight_device);
+}
+
+/*
+ * Read/ write bool sysfs macro
+ */
+#define show_set_bool(value, cap) \
+static ssize_t \
+show_bool_##value(struct device *dev, struct device_attribute *attr, \
+        char *buf) \
+{ \
+        u32 result; \
+        acpi_status status = get_u32(&result, cap); \
+        if (ACPI_SUCCESS(status)) \
+                return sprintf(buf, "%u\n", result); \
+        return sprintf(buf, "Read error\n"); \
+} \
+\
+static ssize_t \
+set_bool_##value(struct device *dev, struct device_attribute *attr, \
+        const char *buf, size_t count) \
+{ \
+        u32 tmp = simple_strtoul(buf, NULL, 10); \
+        acpi_status status = set_u32(tmp, cap); \
+                if (ACPI_FAILURE(status)) \
+                        return -EINVAL; \
+        return count; \
+} \
+static DEVICE_ATTR(value, S_IWUGO | S_IRUGO | S_IWUSR, \
+        show_bool_##value, set_bool_##value);
+
+show_set_bool(wireless, ACER_CAP_WIRELESS);
+show_set_bool(bluetooth, ACER_CAP_BLUETOOTH);
+show_set_bool(threeg, ACER_CAP_THREEG);
+
+/*
+ * Read interface sysfs macro
+ */
+static ssize_t show_interface(struct device *dev, struct device_attribute *attr,
+        char *buf)
+{
+        switch (interface->type) {
+        case ACER_AMW0:
+                return sprintf(buf, "AMW0\n");
+        case ACER_AMW0_V2:
+                return sprintf(buf, "AMW0 v2\n");
+        case ACER_WMID:
+                return sprintf(buf, "WMID\n");
+        default:
+                return sprintf(buf, "Error!\n");
+        }
+}
+
+static DEVICE_ATTR(interface, S_IWUGO | S_IRUGO | S_IWUSR,
+        show_interface, NULL);
+
+/*
+ * Platform device
+ */
+static int __devinit acer_platform_probe(struct platform_device *device)
+{
+        int err;
+
+        if (has_cap(ACER_CAP_MAILLED)) {
+                err = acer_led_init(&device->dev);
+                if (err)
+                        goto error_mailled;
+        }
+
+        if (has_cap(ACER_CAP_BRIGHTNESS)) {
+                err = acer_backlight_init(&device->dev);
+                if (err)
+                        goto error_brightness;
+        }
+
+        return 0;
+
+error_brightness:
+        acer_led_exit();
+error_mailled:
+        return err;
+}
+
+static int acer_platform_remove(struct platform_device *device)
+{
+        if (has_cap(ACER_CAP_MAILLED))
+                acer_led_exit();
+        if (has_cap(ACER_CAP_BRIGHTNESS))
+                acer_backlight_exit();
+        return 0;
+}
+
+static int acer_platform_suspend(struct platform_device *dev,
+pm_message_t state)
+{
+        u32 value;
+        struct acer_data *data = &interface->data;
+
+        if (!data)
+                return -ENOMEM;
+
+        if (has_cap(ACER_CAP_WIRELESS)) {
+                get_u32(&value, ACER_CAP_WIRELESS);
+                data->wireless = value;
+        }
+
+        if (has_cap(ACER_CAP_BLUETOOTH)) {
+                get_u32(&value, ACER_CAP_BLUETOOTH);
+                data->bluetooth = value;
+        }
+
+        if (has_cap(ACER_CAP_MAILLED)) {
+                get_u32(&value, ACER_CAP_MAILLED);
+                data->mailled = value;
+        }
+
+        if (has_cap(ACER_CAP_BRIGHTNESS)) {
+                get_u32(&value, ACER_CAP_BRIGHTNESS);
+                data->brightness = value;
+        }
+
+        return 0;
+}
+
+static int acer_platform_resume(struct platform_device *device)
+{
+        struct acer_data *data = &interface->data;
+
+        if (!data)
+                return -ENOMEM;
+
+        if (has_cap(ACER_CAP_WIRELESS))
+                set_u32(data->wireless, ACER_CAP_WIRELESS);
+
+        if (has_cap(ACER_CAP_BLUETOOTH))
+                set_u32(data->bluetooth, ACER_CAP_BLUETOOTH);
+
+        if (has_cap(ACER_CAP_THREEG))
+                set_u32(data->threeg, ACER_CAP_THREEG);
+
+        if (has_cap(ACER_CAP_MAILLED))
+                set_u32(data->mailled, ACER_CAP_MAILLED);
+
+        if (has_cap(ACER_CAP_BRIGHTNESS))
+                set_u32(data->brightness, ACER_CAP_BRIGHTNESS);
+
+        return 0;
+}
+
+static struct platform_driver acer_platform_driver = {
+        .driver = {
+                .name = "acer-wmi",
+                .owner = THIS_MODULE,
+        },
+        .probe = acer_platform_probe,
+        .remove = acer_platform_remove,
+        .suspend = acer_platform_suspend,
+        .resume = acer_platform_resume,
+};
+
+static struct platform_device *acer_platform_device;
+
+static int remove_sysfs(struct platform_device *device)
+{
+        if (has_cap(ACER_CAP_WIRELESS))
+                device_remove_file(&device->dev, &dev_attr_wireless);
+
+        if (has_cap(ACER_CAP_BLUETOOTH))
+                device_remove_file(&device->dev, &dev_attr_bluetooth);
+
+        if (has_cap(ACER_CAP_THREEG))
+                device_remove_file(&device->dev, &dev_attr_threeg);
+
+        device_remove_file(&device->dev, &dev_attr_interface);
+
+        return 0;
+}
+
+static int create_sysfs(void)
+{
+        int retval = -ENOMEM;
+
+        if (has_cap(ACER_CAP_WIRELESS)) {
+                retval = device_create_file(&acer_platform_device->dev,
+                        &dev_attr_wireless);
+                if (retval)
+                        goto error_sysfs;
+        }
+
+        if (has_cap(ACER_CAP_BLUETOOTH)) {
+                retval = device_create_file(&acer_platform_device->dev,
+                        &dev_attr_bluetooth);
+                if (retval)
+                        goto error_sysfs;
+        }
+
+        if (has_cap(ACER_CAP_THREEG)) {
+                retval = device_create_file(&acer_platform_device->dev,
+                        &dev_attr_threeg);
+                if (retval)
+                        goto error_sysfs;
+        }
+
+        retval = device_create_file(&acer_platform_device->dev,
+                &dev_attr_interface);
+        if (retval)
+                goto error_sysfs;
+
+        return 0;
+
+error_sysfs:
+                remove_sysfs(acer_platform_device);
+        return retval;
+}
+
+static int __init acer_wmi_init(void)
+{
+        int err;
+
+        printk(ACER_INFO "Acer Laptop ACPI-WMI Extras version %s\n",
+                        ACER_WMI_VERSION);
+
+        /*
+         * Detect which ACPI-WMI interface we're using.
+         */
+        if (wmi_has_guid(AMW0_GUID1) && wmi_has_guid(WMID_GUID1))
+                interface = &AMW0_V2_interface;
+
+        if (!wmi_has_guid(AMW0_GUID1) && wmi_has_guid(WMID_GUID1))
+                interface = &wmid_interface;
+
+        if (wmi_has_guid(WMID_GUID2) && interface) {
+                if (ACPI_FAILURE(WMID_set_capabilities())) {
+                        printk(ACER_ERR "Unable to detect available devices\n");
+                        return -ENODEV;
+                }
+        } else if (!wmi_has_guid(WMID_GUID2) && interface) {
+                printk(ACER_ERR "Unable to detect available devices\n");
+                return -ENODEV;
+        }
+
+        if (wmi_has_guid(AMW0_GUID1) && !wmi_has_guid(WMID_GUID1)) {
+                interface = &AMW0_interface;
+
+                if (ACPI_FAILURE(AMW0_set_capabilities())) {
+                        printk(ACER_ERR "Unable to detect available devices\n");
+                        return -ENODEV;
+                }
+        }
+
+        if (wmi_has_guid(AMW0_GUID1)) {
+                if (ACPI_FAILURE(AMW0_find_mailled()))
+                        printk(ACER_ERR "Unable to detect mail LED\n");
+        }
+
+        find_quirks();
+
+        if (!interface) {
+                printk(ACER_ERR "No or unsupported WMI interface, unable to ");
+                printk(KERN_CONT "load.\n");
+                return -ENODEV;
+        }
+
+        if (platform_driver_register(&acer_platform_driver)) {
+                printk(ACER_ERR "Unable to register platform driver.\n");
+                goto error_platform_register;
+        }
+        acer_platform_device = platform_device_alloc("acer-wmi", -1);
+        platform_device_add(acer_platform_device);
+
+        err = create_sysfs();
+        if (err)
+                return err;
+
+        /* Override any initial settings with values from the commandline */
+        acer_commandline_init();
+
+        return 0;
+
+error_platform_register:
+        return -ENODEV;
+}
+
+static void __exit acer_wmi_exit(void)
+{
+        remove_sysfs(acer_platform_device);
+        platform_device_del(acer_platform_device);
+        platform_driver_unregister(&acer_platform_driver);
+
+        printk(ACER_INFO "Acer Laptop WMI Extras unloaded\n");
+        return;
+}
+
+module_init(acer_wmi_init);
+module_exit(acer_wmi_exit);