acpi-video-detect: video: Make video_detect code part of the video module
This is a preparation patch for the backlight interface selection logic
cleanup, there are 2 reasons to not always build the video_detect code
into the kernel:
1) In order for the video_detect.c to also deal with / select native
backlight interfaces on win8 systems, instead of doing this in video.c
where it does not belong, video_detect.c needs to call into the backlight
class code. Which cannot be done if it is builtin and the blacklight class
is not.
2) Currently all the platform/x86 drivers which have quirks to prefer
the vendor driver over acpi-video call acpi_video_unregister_backlight()
to remove the acpi-video backlight interface, this logic really belongs
in video_detect.c, which will cause video_detect.c to depend on symbols of
video.c and video.c already depends on video_detect.c symbols, so they
really need to be a single module.
Note that this commits make 2 changes so as to maintain 100% kernel
commandline compatibility:
1) The __setup call for the acpi_backlight= handling is moved to
acpi/util.c as __setup may only be used by code which is alwasy builtin
2) video.c is renamed to acpi_video.c so that it can be combined with
video_detect.c into video.ko
This commit also makes changes to drivers/platform/x86/Kconfig to ensure
that drivers which use acpi_video_backlight_support() from video_detect.c,
will not be built-in when acpi_video is not built in. This also changes
some "select" uses to "depends on" to avoid dependency loops.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
new file mode 100644
index 0000000..db4f353
--- /dev/null
+++ b/drivers/acpi/acpi_video.c
@@ -0,0 +1,2275 @@
+/*
+ * video.c - ACPI Video Driver
+ *
+ * Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
+ * Copyright (C) 2004 Bruno Ducrot <ducrot@poupinou.org>
+ * Copyright (C) 2006 Thomas Tuttle <linux-kernel@ttuttle.net>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * 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/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/input.h>
+#include <linux/backlight.h>
+#include <linux/thermal.h>
+#include <linux/sort.h>
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+#include <linux/slab.h>
+#include <linux/dmi.h>
+#include <linux/suspend.h>
+#include <linux/acpi.h>
+#include <acpi/video.h>
+#include <asm/uaccess.h>
+
+#define PREFIX "ACPI: "
+
+#define ACPI_VIDEO_BUS_NAME "Video Bus"
+#define ACPI_VIDEO_DEVICE_NAME "Video Device"
+#define ACPI_VIDEO_NOTIFY_SWITCH 0x80
+#define ACPI_VIDEO_NOTIFY_PROBE 0x81
+#define ACPI_VIDEO_NOTIFY_CYCLE 0x82
+#define ACPI_VIDEO_NOTIFY_NEXT_OUTPUT 0x83
+#define ACPI_VIDEO_NOTIFY_PREV_OUTPUT 0x84
+
+#define ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS 0x85
+#define ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS 0x86
+#define ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS 0x87
+#define ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS 0x88
+#define ACPI_VIDEO_NOTIFY_DISPLAY_OFF 0x89
+
+#define MAX_NAME_LEN 20
+
+#define _COMPONENT ACPI_VIDEO_COMPONENT
+ACPI_MODULE_NAME("video");
+
+MODULE_AUTHOR("Bruno Ducrot");
+MODULE_DESCRIPTION("ACPI Video Driver");
+MODULE_LICENSE("GPL");
+
+static bool brightness_switch_enabled = 1;
+module_param(brightness_switch_enabled, bool, 0644);
+
+/*
+ * By default, we don't allow duplicate ACPI video bus devices
+ * under the same VGA controller
+ */
+static bool allow_duplicates;
+module_param(allow_duplicates, bool, 0644);
+
+/*
+ * For Windows 8 systems: used to decide if video module
+ * should skip registering backlight interface of its own.
+ */
+enum {
+ NATIVE_BACKLIGHT_NOT_SET = -1,
+ NATIVE_BACKLIGHT_OFF,
+ NATIVE_BACKLIGHT_ON,
+};
+
+static int use_native_backlight_param = NATIVE_BACKLIGHT_NOT_SET;
+module_param_named(use_native_backlight, use_native_backlight_param, int, 0444);
+static int use_native_backlight_dmi = NATIVE_BACKLIGHT_NOT_SET;
+
+static int disable_backlight_sysfs_if = -1;
+module_param(disable_backlight_sysfs_if, int, 0444);
+
+static int register_count;
+static struct mutex video_list_lock;
+static struct list_head video_bus_head;
+static int acpi_video_bus_add(struct acpi_device *device);
+static int acpi_video_bus_remove(struct acpi_device *device);
+static void acpi_video_bus_notify(struct acpi_device *device, u32 event);
+
+static const struct acpi_device_id video_device_ids[] = {
+ {ACPI_VIDEO_HID, 0},
+ {"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, video_device_ids);
+
+static struct acpi_driver acpi_video_bus = {
+ .name = "video",
+ .class = ACPI_VIDEO_CLASS,
+ .ids = video_device_ids,
+ .ops = {
+ .add = acpi_video_bus_add,
+ .remove = acpi_video_bus_remove,
+ .notify = acpi_video_bus_notify,
+ },
+};
+
+struct acpi_video_bus_flags {
+ u8 multihead:1; /* can switch video heads */
+ u8 rom:1; /* can retrieve a video rom */
+ u8 post:1; /* can configure the head to */
+ u8 reserved:5;
+};
+
+struct acpi_video_bus_cap {
+ u8 _DOS:1; /* Enable/Disable output switching */
+ u8 _DOD:1; /* Enumerate all devices attached to display adapter */
+ u8 _ROM:1; /* Get ROM Data */
+ u8 _GPD:1; /* Get POST Device */
+ u8 _SPD:1; /* Set POST Device */
+ u8 _VPO:1; /* Video POST Options */
+ u8 reserved:2;
+};
+
+struct acpi_video_device_attrib {
+ u32 display_index:4; /* A zero-based instance of the Display */
+ u32 display_port_attachment:4; /* This field differentiates the display type */
+ u32 display_type:4; /* Describe the specific type in use */
+ u32 vendor_specific:4; /* Chipset Vendor Specific */
+ u32 bios_can_detect:1; /* BIOS can detect the device */
+ u32 depend_on_vga:1; /* Non-VGA output device whose power is related to
+ the VGA device. */
+ u32 pipe_id:3; /* For VGA multiple-head devices. */
+ u32 reserved:10; /* Must be 0 */
+ u32 device_id_scheme:1; /* Device ID Scheme */
+};
+
+struct acpi_video_enumerated_device {
+ union {
+ u32 int_val;
+ struct acpi_video_device_attrib attrib;
+ } value;
+ struct acpi_video_device *bind_info;
+};
+
+struct acpi_video_bus {
+ struct acpi_device *device;
+ bool backlight_registered;
+ bool backlight_notifier_registered;
+ u8 dos_setting;
+ struct acpi_video_enumerated_device *attached_array;
+ u8 attached_count;
+ u8 child_count;
+ struct acpi_video_bus_cap cap;
+ struct acpi_video_bus_flags flags;
+ struct list_head video_device_list;
+ struct mutex device_list_lock; /* protects video_device_list */
+ struct list_head entry;
+ struct input_dev *input;
+ char phys[32]; /* for input device */
+ struct notifier_block pm_nb;
+ struct notifier_block backlight_nb;
+};
+
+struct acpi_video_device_flags {
+ u8 crt:1;
+ u8 lcd:1;
+ u8 tvout:1;
+ u8 dvi:1;
+ u8 bios:1;
+ u8 unknown:1;
+ u8 notify:1;
+ u8 reserved:1;
+};
+
+struct acpi_video_device_cap {
+ u8 _ADR:1; /* Return the unique ID */
+ u8 _BCL:1; /* Query list of brightness control levels supported */
+ u8 _BCM:1; /* Set the brightness level */
+ u8 _BQC:1; /* Get current brightness level */
+ u8 _BCQ:1; /* Some buggy BIOS uses _BCQ instead of _BQC */
+ u8 _DDC:1; /* Return the EDID for this device */
+};
+
+struct acpi_video_brightness_flags {
+ u8 _BCL_no_ac_battery_levels:1; /* no AC/Battery levels in _BCL */
+ u8 _BCL_reversed:1; /* _BCL package is in a reversed order */
+ u8 _BQC_use_index:1; /* _BQC returns an index value */
+};
+
+struct acpi_video_device_brightness {
+ int curr;
+ int count;
+ int *levels;
+ struct acpi_video_brightness_flags flags;
+};
+
+struct acpi_video_device {
+ unsigned long device_id;
+ struct acpi_video_device_flags flags;
+ struct acpi_video_device_cap cap;
+ struct list_head entry;
+ struct delayed_work switch_brightness_work;
+ int switch_brightness_event;
+ struct acpi_video_bus *video;
+ struct acpi_device *dev;
+ struct acpi_video_device_brightness *brightness;
+ struct backlight_device *backlight;
+ struct thermal_cooling_device *cooling_dev;
+};
+
+static const char device_decode[][30] = {
+ "motherboard VGA device",
+ "PCI VGA device",
+ "AGP VGA device",
+ "UNKNOWN",
+};
+
+static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data);
+static void acpi_video_device_rebind(struct acpi_video_bus *video);
+static void acpi_video_device_bind(struct acpi_video_bus *video,
+ struct acpi_video_device *device);
+static int acpi_video_device_enumerate(struct acpi_video_bus *video);
+static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
+ int level);
+static int acpi_video_device_lcd_get_level_current(
+ struct acpi_video_device *device,
+ unsigned long long *level, bool raw);
+static int acpi_video_get_next_level(struct acpi_video_device *device,
+ u32 level_current, u32 event);
+static void acpi_video_switch_brightness(struct work_struct *work);
+
+static bool acpi_video_use_native_backlight(void)
+{
+ if (use_native_backlight_param != NATIVE_BACKLIGHT_NOT_SET)
+ return use_native_backlight_param;
+ else if (use_native_backlight_dmi != NATIVE_BACKLIGHT_NOT_SET)
+ return use_native_backlight_dmi;
+ return acpi_osi_is_win8();
+}
+
+bool acpi_video_verify_backlight_support(void)
+{
+ if (acpi_video_use_native_backlight() &&
+ backlight_device_registered(BACKLIGHT_RAW))
+ return false;
+ return acpi_video_backlight_support();
+}
+EXPORT_SYMBOL_GPL(acpi_video_verify_backlight_support);
+
+/* backlight device sysfs support */
+static int acpi_video_get_brightness(struct backlight_device *bd)
+{
+ unsigned long long cur_level;
+ int i;
+ struct acpi_video_device *vd = bl_get_data(bd);
+
+ if (acpi_video_device_lcd_get_level_current(vd, &cur_level, false))
+ return -EINVAL;
+ for (i = 2; i < vd->brightness->count; i++) {
+ if (vd->brightness->levels[i] == cur_level)
+ /*
+ * The first two entries are special - see page 575
+ * of the ACPI spec 3.0
+ */
+ return i - 2;
+ }
+ return 0;
+}
+
+static int acpi_video_set_brightness(struct backlight_device *bd)
+{
+ int request_level = bd->props.brightness + 2;
+ struct acpi_video_device *vd = bl_get_data(bd);
+
+ cancel_delayed_work(&vd->switch_brightness_work);
+ return acpi_video_device_lcd_set_level(vd,
+ vd->brightness->levels[request_level]);
+}
+
+static const struct backlight_ops acpi_backlight_ops = {
+ .get_brightness = acpi_video_get_brightness,
+ .update_status = acpi_video_set_brightness,
+};
+
+/* thermal cooling device callbacks */
+static int video_get_max_state(struct thermal_cooling_device *cooling_dev, unsigned
+ long *state)
+{
+ struct acpi_device *device = cooling_dev->devdata;
+ struct acpi_video_device *video = acpi_driver_data(device);
+
+ *state = video->brightness->count - 3;
+ return 0;
+}
+
+static int video_get_cur_state(struct thermal_cooling_device *cooling_dev, unsigned
+ long *state)
+{
+ struct acpi_device *device = cooling_dev->devdata;
+ struct acpi_video_device *video = acpi_driver_data(device);
+ unsigned long long level;
+ int offset;
+
+ if (acpi_video_device_lcd_get_level_current(video, &level, false))
+ return -EINVAL;
+ for (offset = 2; offset < video->brightness->count; offset++)
+ if (level == video->brightness->levels[offset]) {
+ *state = video->brightness->count - offset - 1;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static int
+video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
+{
+ struct acpi_device *device = cooling_dev->devdata;
+ struct acpi_video_device *video = acpi_driver_data(device);
+ int level;
+
+ if (state >= video->brightness->count - 2)
+ return -EINVAL;
+
+ state = video->brightness->count - state;
+ level = video->brightness->levels[state - 1];
+ return acpi_video_device_lcd_set_level(video, level);
+}
+
+static const struct thermal_cooling_device_ops video_cooling_ops = {
+ .get_max_state = video_get_max_state,
+ .get_cur_state = video_get_cur_state,
+ .set_cur_state = video_set_cur_state,
+};
+
+/*
+ * --------------------------------------------------------------------------
+ * Video Management
+ * --------------------------------------------------------------------------
+ */
+
+static int
+acpi_video_device_lcd_query_levels(struct acpi_video_device *device,
+ union acpi_object **levels)
+{
+ int status;
+ struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+ union acpi_object *obj;
+
+
+ *levels = NULL;
+
+ status = acpi_evaluate_object(device->dev->handle, "_BCL", NULL, &buffer);
+ if (!ACPI_SUCCESS(status))
+ return status;
+ obj = (union acpi_object *)buffer.pointer;
+ if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
+ printk(KERN_ERR PREFIX "Invalid _BCL data\n");
+ status = -EFAULT;
+ goto err;
+ }
+
+ *levels = obj;
+
+ return 0;
+
+err:
+ kfree(buffer.pointer);
+
+ return status;
+}
+
+static int
+acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
+{
+ int status;
+ int state;
+
+ status = acpi_execute_simple_method(device->dev->handle,
+ "_BCM", level);
+ if (ACPI_FAILURE(status)) {
+ ACPI_ERROR((AE_INFO, "Evaluating _BCM failed"));
+ return -EIO;
+ }
+
+ device->brightness->curr = level;
+ for (state = 2; state < device->brightness->count; state++)
+ if (level == device->brightness->levels[state]) {
+ if (device->backlight)
+ device->backlight->props.brightness = state - 2;
+ return 0;
+ }
+
+ ACPI_ERROR((AE_INFO, "Current brightness invalid"));
+ return -EINVAL;
+}
+
+/*
+ * For some buggy _BQC methods, we need to add a constant value to
+ * the _BQC return value to get the actual current brightness level
+ */
+
+static int bqc_offset_aml_bug_workaround;
+static int __init video_set_bqc_offset(const struct dmi_system_id *d)
+{
+ bqc_offset_aml_bug_workaround = 9;
+ return 0;
+}
+
+static int __init video_disable_native_backlight(const struct dmi_system_id *d)
+{
+ use_native_backlight_dmi = NATIVE_BACKLIGHT_OFF;
+ return 0;
+}
+
+static int __init video_enable_native_backlight(const struct dmi_system_id *d)
+{
+ use_native_backlight_dmi = NATIVE_BACKLIGHT_ON;
+ return 0;
+}
+
+static int __init video_disable_backlight_sysfs_if(
+ const struct dmi_system_id *d)
+{
+ if (disable_backlight_sysfs_if == -1)
+ disable_backlight_sysfs_if = 1;
+ return 0;
+}
+
+static struct dmi_system_id video_dmi_table[] __initdata = {
+ /*
+ * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
+ */
+ {
+ .callback = video_set_bqc_offset,
+ .ident = "Acer Aspire 5720",
+ .matches = {
+ DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
+ },
+ },
+ {
+ .callback = video_set_bqc_offset,
+ .ident = "Acer Aspire 5710Z",
+ .matches = {
+ DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
+ },
+ },
+ {
+ .callback = video_set_bqc_offset,
+ .ident = "eMachines E510",
+ .matches = {
+ DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
+ },
+ },
+ {
+ .callback = video_set_bqc_offset,
+ .ident = "Acer Aspire 5315",
+ .matches = {
+ DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
+ },
+ },
+ {
+ .callback = video_set_bqc_offset,
+ .ident = "Acer Aspire 7720",
+ .matches = {
+ DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
+ },
+ },
+
+ /*
+ * These models have a working acpi_video backlight control, and using
+ * native backlight causes a regression where backlight does not work
+ * when userspace is not handling brightness key events. Disable
+ * native_backlight on these to fix this:
+ * https://bugzilla.kernel.org/show_bug.cgi?id=81691
+ */
+ {
+ .callback = video_disable_native_backlight,
+ .ident = "ThinkPad T420",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+ DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
+ },
+ },
+ {
+ .callback = video_disable_native_backlight,
+ .ident = "ThinkPad T520",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+ DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
+ },
+ },
+ {
+ .callback = video_disable_native_backlight,
+ .ident = "ThinkPad X201s",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+ DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
+ },
+ },
+
+ /* The native backlight controls do not work on some older machines */
+ {
+ /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
+ .callback = video_disable_native_backlight,
+ .ident = "HP ENVY 15 Notebook",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
+ },
+ },
+
+ {
+ .callback = video_disable_native_backlight,
+ .ident = "SAMSUNG 870Z5E/880Z5E/680Z5E",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
+ },
+ },
+ {
+ .callback = video_disable_native_backlight,
+ .ident = "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "370R4E/370R4V/370R5E/3570RE/370R5V"),
+ },
+ },
+ {
+ /* https://bugzilla.redhat.com/show_bug.cgi?id=1186097 */
+ .callback = video_disable_native_backlight,
+ .ident = "SAMSUNG 3570R/370R/470R/450R/510R/4450RV",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "3570R/370R/470R/450R/510R/4450RV"),
+ },
+ },
+ {
+ /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
+ .callback = video_disable_native_backlight,
+ .ident = "SAMSUNG 730U3E/740U3E",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"),
+ },
+ },
+ {
+ /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
+ .callback = video_disable_native_backlight,
+ .ident = "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "900X3C/900X3D/900X3E/900X4C/900X4D"),
+ },
+ },
+
+ {
+ /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
+ .callback = video_disable_native_backlight,
+ .ident = "Dell XPS15 L521X",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
+ },
+ },
+
+ /* Non win8 machines which need native backlight nevertheless */
+ {
+ /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
+ .callback = video_enable_native_backlight,
+ .ident = "Lenovo Ideapad Z570",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "102434U"),
+ },
+ },
+ {
+ /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
+ .callback = video_enable_native_backlight,
+ .ident = "Apple MacBook Pro 12,1",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
+ },
+ },
+
+ /*
+ * Some machines have a broken acpi-video interface for brightness
+ * control, but still need an acpi_video_device_lcd_set_level() call
+ * on resume to turn the backlight power on. We Enable backlight
+ * control on these systems, but do not register a backlight sysfs
+ * as brightness control does not work.
+ */
+ {
+ /* https://bugs.freedesktop.org/show_bug.cgi?id=82634 */
+ .callback = video_disable_backlight_sysfs_if,
+ .ident = "Toshiba Portege R830",
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
+ DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R830"),
+ },
+ },
+ {}
+};
+
+static unsigned long long
+acpi_video_bqc_value_to_level(struct acpi_video_device *device,
+ unsigned long long bqc_value)
+{
+ unsigned long long level;
+
+ if (device->brightness->flags._BQC_use_index) {
+ /*
+ * _BQC returns an index that doesn't account for
+ * the first 2 items with special meaning, so we need
+ * to compensate for that by offsetting ourselves
+ */
+ if (device->brightness->flags._BCL_reversed)
+ bqc_value = device->brightness->count - 3 - bqc_value;
+
+ level = device->brightness->levels[bqc_value + 2];
+ } else {
+ level = bqc_value;
+ }
+
+ level += bqc_offset_aml_bug_workaround;
+
+ return level;
+}
+
+static int
+acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
+ unsigned long long *level, bool raw)
+{
+ acpi_status status = AE_OK;
+ int i;
+
+ if (device->cap._BQC || device->cap._BCQ) {
+ char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
+
+ status = acpi_evaluate_integer(device->dev->handle, buf,
+ NULL, level);
+ if (ACPI_SUCCESS(status)) {
+ if (raw) {
+ /*
+ * Caller has indicated he wants the raw
+ * value returned by _BQC, so don't furtherly
+ * mess with the value.
+ */
+ return 0;
+ }
+
+ *level = acpi_video_bqc_value_to_level(device, *level);
+
+ for (i = 2; i < device->brightness->count; i++)
+ if (device->brightness->levels[i] == *level) {
+ device->brightness->curr = *level;
+ return 0;
+ }
+ /*
+ * BQC returned an invalid level.
+ * Stop using it.
+ */
+ ACPI_WARNING((AE_INFO,
+ "%s returned an invalid level",
+ buf));
+ device->cap._BQC = device->cap._BCQ = 0;
+ } else {
+ /*
+ * Fixme:
+ * should we return an error or ignore this failure?
+ * dev->brightness->curr is a cached value which stores
+ * the correct current backlight level in most cases.
+ * ACPI video backlight still works w/ buggy _BQC.
+ * http://bugzilla.kernel.org/show_bug.cgi?id=12233
+ */
+ ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
+ device->cap._BQC = device->cap._BCQ = 0;
+ }
+ }
+
+ *level = device->brightness->curr;
+ return 0;
+}
+
+static int
+acpi_video_device_EDID(struct acpi_video_device *device,
+ union acpi_object **edid, ssize_t length)
+{
+ int status;
+ struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+ union acpi_object *obj;
+ union acpi_object arg0 = { ACPI_TYPE_INTEGER };
+ struct acpi_object_list args = { 1, &arg0 };
+
+
+ *edid = NULL;
+
+ if (!device)
+ return -ENODEV;
+ if (length == 128)
+ arg0.integer.value = 1;
+ else if (length == 256)
+ arg0.integer.value = 2;
+ else
+ return -EINVAL;
+
+ status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ obj = buffer.pointer;
+
+ if (obj && obj->type == ACPI_TYPE_BUFFER)
+ *edid = obj;
+ else {
+ printk(KERN_ERR PREFIX "Invalid _DDC data\n");
+ status = -EFAULT;
+ kfree(obj);
+ }
+
+ return status;
+}
+
+/* bus */
+
+/*
+ * Arg:
+ * video : video bus device pointer
+ * bios_flag :
+ * 0. The system BIOS should NOT automatically switch(toggle)
+ * the active display output.
+ * 1. The system BIOS should automatically switch (toggle) the
+ * active display output. No switch event.
+ * 2. The _DGS value should be locked.
+ * 3. The system BIOS should not automatically switch (toggle) the
+ * active display output, but instead generate the display switch
+ * event notify code.
+ * lcd_flag :
+ * 0. The system BIOS should automatically control the brightness level
+ * of the LCD when the power changes from AC to DC
+ * 1. The system BIOS should NOT automatically control the brightness
+ * level of the LCD when the power changes from AC to DC.
+ * Return Value:
+ * -EINVAL wrong arg.
+ */
+
+static int
+acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
+{
+ acpi_status status;
+
+ if (!video->cap._DOS)
+ return 0;
+
+ if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
+ return -EINVAL;
+ video->dos_setting = (lcd_flag << 2) | bios_flag;
+ status = acpi_execute_simple_method(video->device->handle, "_DOS",
+ (lcd_flag << 2) | bios_flag);
+ if (ACPI_FAILURE(status))
+ return -EIO;
+
+ return 0;
+}
+
+/*
+ * Simple comparison function used to sort backlight levels.
+ */
+
+static int
+acpi_video_cmp_level(const void *a, const void *b)
+{
+ return *(int *)a - *(int *)b;
+}
+
+/*
+ * Decides if _BQC/_BCQ for this system is usable
+ *
+ * We do this by changing the level first and then read out the current
+ * brightness level, if the value does not match, find out if it is using
+ * index. If not, clear the _BQC/_BCQ capability.
+ */
+static int acpi_video_bqc_quirk(struct acpi_video_device *device,
+ int max_level, int current_level)
+{
+ struct acpi_video_device_brightness *br = device->brightness;
+ int result;
+ unsigned long long level;
+ int test_level;
+
+ /* don't mess with existing known broken systems */
+ if (bqc_offset_aml_bug_workaround)
+ return 0;
+
+ /*
+ * Some systems always report current brightness level as maximum
+ * through _BQC, we need to test another value for them.
+ */
+ test_level = current_level == max_level ? br->levels[3] : max_level;
+
+ result = acpi_video_device_lcd_set_level(device, test_level);
+ if (result)
+ return result;
+
+ result = acpi_video_device_lcd_get_level_current(device, &level, true);
+ if (result)
+ return result;
+
+ if (level != test_level) {
+ /* buggy _BQC found, need to find out if it uses index */
+ if (level < br->count) {
+ if (br->flags._BCL_reversed)
+ level = br->count - 3 - level;
+ if (br->levels[level + 2] == test_level)
+ br->flags._BQC_use_index = 1;
+ }
+
+ if (!br->flags._BQC_use_index)
+ device->cap._BQC = device->cap._BCQ = 0;
+ }
+
+ return 0;
+}
+
+
+/*
+ * Arg:
+ * device : video output device (LCD, CRT, ..)
+ *
+ * Return Value:
+ * Maximum brightness level
+ *
+ * Allocate and initialize device->brightness.
+ */
+
+static int
+acpi_video_init_brightness(struct acpi_video_device *device)
+{
+ union acpi_object *obj = NULL;
+ int i, max_level = 0, count = 0, level_ac_battery = 0;
+ unsigned long long level, level_old;
+ union acpi_object *o;
+ struct acpi_video_device_brightness *br = NULL;
+ int result = -EINVAL;
+ u32 value;
+
+ if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
+ "LCD brightness level\n"));
+ goto out;
+ }
+
+ if (obj->package.count < 2)
+ goto out;
+
+ br = kzalloc(sizeof(*br), GFP_KERNEL);
+ if (!br) {
+ printk(KERN_ERR "can't allocate memory\n");
+ result = -ENOMEM;
+ goto out;
+ }
+
+ br->levels = kmalloc((obj->package.count + 2) * sizeof *(br->levels),
+ GFP_KERNEL);
+ if (!br->levels) {
+ result = -ENOMEM;
+ goto out_free;
+ }
+
+ for (i = 0; i < obj->package.count; i++) {
+ o = (union acpi_object *)&obj->package.elements[i];
+ if (o->type != ACPI_TYPE_INTEGER) {
+ printk(KERN_ERR PREFIX "Invalid data\n");
+ continue;
+ }
+ value = (u32) o->integer.value;
+ /* Skip duplicate entries */
+ if (count > 2 && br->levels[count - 1] == value)
+ continue;
+
+ br->levels[count] = value;
+
+ if (br->levels[count] > max_level)
+ max_level = br->levels[count];
+ count++;
+ }
+
+ /*
+ * some buggy BIOS don't export the levels
+ * when machine is on AC/Battery in _BCL package.
+ * In this case, the first two elements in _BCL packages
+ * are also supported brightness levels that OS should take care of.
+ */
+ for (i = 2; i < count; i++) {
+ if (br->levels[i] == br->levels[0])
+ level_ac_battery++;
+ if (br->levels[i] == br->levels[1])
+ level_ac_battery++;
+ }
+
+ if (level_ac_battery < 2) {
+ level_ac_battery = 2 - level_ac_battery;
+ br->flags._BCL_no_ac_battery_levels = 1;
+ for (i = (count - 1 + level_ac_battery); i >= 2; i--)
+ br->levels[i] = br->levels[i - level_ac_battery];
+ count += level_ac_battery;
+ } else if (level_ac_battery > 2)
+ ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
+
+ /* Check if the _BCL package is in a reversed order */
+ if (max_level == br->levels[2]) {
+ br->flags._BCL_reversed = 1;
+ sort(&br->levels[2], count - 2, sizeof(br->levels[2]),
+ acpi_video_cmp_level, NULL);
+ } else if (max_level != br->levels[count - 1])
+ ACPI_ERROR((AE_INFO,
+ "Found unordered _BCL package"));
+
+ br->count = count;
+ device->brightness = br;
+
+ /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
+ br->curr = level = max_level;
+
+ if (!device->cap._BQC)
+ goto set_level;
+
+ result = acpi_video_device_lcd_get_level_current(device,
+ &level_old, true);
+ if (result)
+ goto out_free_levels;
+
+ result = acpi_video_bqc_quirk(device, max_level, level_old);
+ if (result)
+ goto out_free_levels;
+ /*
+ * cap._BQC may get cleared due to _BQC is found to be broken
+ * in acpi_video_bqc_quirk, so check again here.
+ */
+ if (!device->cap._BQC)
+ goto set_level;
+
+ level = acpi_video_bqc_value_to_level(device, level_old);
+ /*
+ * On some buggy laptops, _BQC returns an uninitialized
+ * value when invoked for the first time, i.e.
+ * level_old is invalid (no matter whether it's a level
+ * or an index). Set the backlight to max_level in this case.
+ */
+ for (i = 2; i < br->count; i++)
+ if (level == br->levels[i])
+ break;
+ if (i == br->count || !level)
+ level = max_level;
+
+set_level:
+ result = acpi_video_device_lcd_set_level(device, level);
+ if (result)
+ goto out_free_levels;
+
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "found %d brightness levels\n", count - 2));
+ kfree(obj);
+ return result;
+
+out_free_levels:
+ kfree(br->levels);
+out_free:
+ kfree(br);
+out:
+ device->brightness = NULL;
+ kfree(obj);
+ return result;
+}
+
+/*
+ * Arg:
+ * device : video output device (LCD, CRT, ..)
+ *
+ * Return Value:
+ * None
+ *
+ * Find out all required AML methods defined under the output
+ * device.
+ */
+
+static void acpi_video_device_find_cap(struct acpi_video_device *device)
+{
+ if (acpi_has_method(device->dev->handle, "_ADR"))
+ device->cap._ADR = 1;
+ if (acpi_has_method(device->dev->handle, "_BCL"))
+ device->cap._BCL = 1;
+ if (acpi_has_method(device->dev->handle, "_BCM"))
+ device->cap._BCM = 1;
+ if (acpi_has_method(device->dev->handle, "_BQC")) {
+ device->cap._BQC = 1;
+ } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
+ printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
+ device->cap._BCQ = 1;
+ }
+
+ if (acpi_has_method(device->dev->handle, "_DDC"))
+ device->cap._DDC = 1;
+}
+
+/*
+ * Arg:
+ * device : video output device (VGA)
+ *
+ * Return Value:
+ * None
+ *
+ * Find out all required AML methods defined under the video bus device.
+ */
+
+static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
+{
+ if (acpi_has_method(video->device->handle, "_DOS"))
+ video->cap._DOS = 1;
+ if (acpi_has_method(video->device->handle, "_DOD"))
+ video->cap._DOD = 1;
+ if (acpi_has_method(video->device->handle, "_ROM"))
+ video->cap._ROM = 1;
+ if (acpi_has_method(video->device->handle, "_GPD"))
+ video->cap._GPD = 1;
+ if (acpi_has_method(video->device->handle, "_SPD"))
+ video->cap._SPD = 1;
+ if (acpi_has_method(video->device->handle, "_VPO"))
+ video->cap._VPO = 1;
+}
+
+/*
+ * Check whether the video bus device has required AML method to
+ * support the desired features
+ */
+
+static int acpi_video_bus_check(struct acpi_video_bus *video)
+{
+ acpi_status status = -ENOENT;
+ struct pci_dev *dev;
+
+ if (!video)
+ return -EINVAL;
+
+ dev = acpi_get_pci_dev(video->device->handle);
+ if (!dev)
+ return -ENODEV;
+ pci_dev_put(dev);
+
+ /*
+ * Since there is no HID, CID and so on for VGA driver, we have
+ * to check well known required nodes.
+ */
+
+ /* Does this device support video switching? */
+ if (video->cap._DOS || video->cap._DOD) {
+ if (!video->cap._DOS) {
+ printk(KERN_WARNING FW_BUG
+ "ACPI(%s) defines _DOD but not _DOS\n",
+ acpi_device_bid(video->device));
+ }
+ video->flags.multihead = 1;
+ status = 0;
+ }
+
+ /* Does this device support retrieving a video ROM? */
+ if (video->cap._ROM) {
+ video->flags.rom = 1;
+ status = 0;
+ }
+
+ /* Does this device support configuring which video device to POST? */
+ if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
+ video->flags.post = 1;
+ status = 0;
+ }
+
+ return status;
+}
+
+/*
+ * --------------------------------------------------------------------------
+ * Driver Interface
+ * --------------------------------------------------------------------------
+ */
+
+/* device interface */
+static struct acpi_video_device_attrib *
+acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
+{
+ struct acpi_video_enumerated_device *ids;
+ int i;
+
+ for (i = 0; i < video->attached_count; i++) {
+ ids = &video->attached_array[i];
+ if ((ids->value.int_val & 0xffff) == device_id)
+ return &ids->value.attrib;
+ }
+
+ return NULL;
+}
+
+static int
+acpi_video_get_device_type(struct acpi_video_bus *video,
+ unsigned long device_id)
+{
+ struct acpi_video_enumerated_device *ids;
+ int i;
+
+ for (i = 0; i < video->attached_count; i++) {
+ ids = &video->attached_array[i];
+ if ((ids->value.int_val & 0xffff) == device_id)
+ return ids->value.int_val;
+ }
+
+ return 0;
+}
+
+static int
+acpi_video_bus_get_one_device(struct acpi_device *device,
+ struct acpi_video_bus *video)
+{
+ unsigned long long device_id;
+ int status, device_type;
+ struct acpi_video_device *data;
+ struct acpi_video_device_attrib *attribute;
+
+ status =
+ acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
+ /* Some device omits _ADR, we skip them instead of fail */
+ if (ACPI_FAILURE(status))
+ return 0;
+
+ data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
+ strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
+ device->driver_data = data;
+
+ data->device_id = device_id;
+ data->video = video;
+ data->dev = device;
+ INIT_DELAYED_WORK(&data->switch_brightness_work,
+ acpi_video_switch_brightness);
+
+ attribute = acpi_video_get_device_attr(video, device_id);
+
+ if (attribute && attribute->device_id_scheme) {
+ switch (attribute->display_type) {
+ case ACPI_VIDEO_DISPLAY_CRT:
+ data->flags.crt = 1;
+ break;
+ case ACPI_VIDEO_DISPLAY_TV:
+ data->flags.tvout = 1;
+ break;
+ case ACPI_VIDEO_DISPLAY_DVI:
+ data->flags.dvi = 1;
+ break;
+ case ACPI_VIDEO_DISPLAY_LCD:
+ data->flags.lcd = 1;
+ break;
+ default:
+ data->flags.unknown = 1;
+ break;
+ }
+ if (attribute->bios_can_detect)
+ data->flags.bios = 1;
+ } else {
+ /* Check for legacy IDs */
+ device_type = acpi_video_get_device_type(video, device_id);
+ /* Ignore bits 16 and 18-20 */
+ switch (device_type & 0xffe2ffff) {
+ case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
+ data->flags.crt = 1;
+ break;
+ case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
+ data->flags.lcd = 1;
+ break;
+ case ACPI_VIDEO_DISPLAY_LEGACY_TV:
+ data->flags.tvout = 1;
+ break;
+ default:
+ data->flags.unknown = 1;
+ }
+ }
+
+ acpi_video_device_bind(video, data);
+ acpi_video_device_find_cap(data);
+
+ mutex_lock(&video->device_list_lock);
+ list_add_tail(&data->entry, &video->video_device_list);
+ mutex_unlock(&video->device_list_lock);
+
+ return status;
+}
+
+/*
+ * Arg:
+ * video : video bus device
+ *
+ * Return:
+ * none
+ *
+ * Enumerate the video device list of the video bus,
+ * bind the ids with the corresponding video devices
+ * under the video bus.
+ */
+
+static void acpi_video_device_rebind(struct acpi_video_bus *video)
+{
+ struct acpi_video_device *dev;
+
+ mutex_lock(&video->device_list_lock);
+
+ list_for_each_entry(dev, &video->video_device_list, entry)
+ acpi_video_device_bind(video, dev);
+
+ mutex_unlock(&video->device_list_lock);
+}
+
+/*
+ * Arg:
+ * video : video bus device
+ * device : video output device under the video
+ * bus
+ *
+ * Return:
+ * none
+ *
+ * Bind the ids with the corresponding video devices
+ * under the video bus.
+ */
+
+static void
+acpi_video_device_bind(struct acpi_video_bus *video,
+ struct acpi_video_device *device)
+{
+ struct acpi_video_enumerated_device *ids;
+ int i;
+
+ for (i = 0; i < video->attached_count; i++) {
+ ids = &video->attached_array[i];
+ if (device->device_id == (ids->value.int_val & 0xffff)) {
+ ids->bind_info = device;
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
+ }
+ }
+}
+
+static bool acpi_video_device_in_dod(struct acpi_video_device *device)
+{
+ struct acpi_video_bus *video = device->video;
+ int i;
+
+ /*
+ * If we have a broken _DOD or we have more than 8 output devices
+ * under the graphics controller node that we can't proper deal with
+ * in the operation region code currently, no need to test.
+ */
+ if (!video->attached_count || video->child_count > 8)
+ return true;
+
+ for (i = 0; i < video->attached_count; i++) {
+ if ((video->attached_array[i].value.int_val & 0xfff) ==
+ (device->device_id & 0xfff))
+ return true;
+ }
+
+ return false;
+}
+
+/*
+ * Arg:
+ * video : video bus device
+ *
+ * Return:
+ * < 0 : error
+ *
+ * Call _DOD to enumerate all devices attached to display adapter
+ *
+ */
+
+static int acpi_video_device_enumerate(struct acpi_video_bus *video)
+{
+ int status;
+ int count;
+ int i;
+ struct acpi_video_enumerated_device *active_list;
+ struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+ union acpi_object *dod = NULL;
+ union acpi_object *obj;
+
+ status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
+ if (!ACPI_SUCCESS(status)) {
+ ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
+ return status;
+ }
+
+ dod = buffer.pointer;
+ if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
+ ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
+ status = -EFAULT;
+ goto out;
+ }
+
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
+ dod->package.count));
+
+ active_list = kcalloc(1 + dod->package.count,
+ sizeof(struct acpi_video_enumerated_device),
+ GFP_KERNEL);
+ if (!active_list) {
+ status = -ENOMEM;
+ goto out;
+ }
+
+ count = 0;
+ for (i = 0; i < dod->package.count; i++) {
+ obj = &dod->package.elements[i];
+
+ if (obj->type != ACPI_TYPE_INTEGER) {
+ printk(KERN_ERR PREFIX
+ "Invalid _DOD data in element %d\n", i);
+ continue;
+ }
+
+ active_list[count].value.int_val = obj->integer.value;
+ active_list[count].bind_info = NULL;
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
+ (int)obj->integer.value));
+ count++;
+ }
+
+ kfree(video->attached_array);
+
+ video->attached_array = active_list;
+ video->attached_count = count;
+
+out:
+ kfree(buffer.pointer);
+ return status;
+}
+
+static int
+acpi_video_get_next_level(struct acpi_video_device *device,
+ u32 level_current, u32 event)
+{
+ int min, max, min_above, max_below, i, l, delta = 255;
+ max = max_below = 0;
+ min = min_above = 255;
+ /* Find closest level to level_current */
+ for (i = 2; i < device->brightness->count; i++) {
+ l = device->brightness->levels[i];
+ if (abs(l - level_current) < abs(delta)) {
+ delta = l - level_current;
+ if (!delta)
+ break;
+ }
+ }
+ /* Ajust level_current to closest available level */
+ level_current += delta;
+ for (i = 2; i < device->brightness->count; i++) {
+ l = device->brightness->levels[i];
+ if (l < min)
+ min = l;
+ if (l > max)
+ max = l;
+ if (l < min_above && l > level_current)
+ min_above = l;
+ if (l > max_below && l < level_current)
+ max_below = l;
+ }
+
+ switch (event) {
+ case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
+ return (level_current < max) ? min_above : min;
+ case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
+ return (level_current < max) ? min_above : max;
+ case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
+ return (level_current > min) ? max_below : min;
+ case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
+ case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
+ return 0;
+ default:
+ return level_current;
+ }
+}
+
+static void
+acpi_video_switch_brightness(struct work_struct *work)
+{
+ struct acpi_video_device *device = container_of(to_delayed_work(work),
+ struct acpi_video_device, switch_brightness_work);
+ unsigned long long level_current, level_next;
+ int event = device->switch_brightness_event;
+ int result = -EINVAL;
+
+ /* no warning message if acpi_backlight=vendor or a quirk is used */
+ if (!device->backlight)
+ return;
+
+ if (!device->brightness)
+ goto out;
+
+ result = acpi_video_device_lcd_get_level_current(device,
+ &level_current,
+ false);
+ if (result)
+ goto out;
+
+ level_next = acpi_video_get_next_level(device, level_current, event);
+
+ result = acpi_video_device_lcd_set_level(device, level_next);
+
+ if (!result)
+ backlight_force_update(device->backlight,
+ BACKLIGHT_UPDATE_HOTKEY);
+
+out:
+ if (result)
+ printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
+}
+
+int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
+ void **edid)
+{
+ struct acpi_video_bus *video;
+ struct acpi_video_device *video_device;
+ union acpi_object *buffer = NULL;
+ acpi_status status;
+ int i, length;
+
+ if (!device || !acpi_driver_data(device))
+ return -EINVAL;
+
+ video = acpi_driver_data(device);
+
+ for (i = 0; i < video->attached_count; i++) {
+ video_device = video->attached_array[i].bind_info;
+ length = 256;
+
+ if (!video_device)
+ continue;
+
+ if (!video_device->cap._DDC)
+ continue;
+
+ if (type) {
+ switch (type) {
+ case ACPI_VIDEO_DISPLAY_CRT:
+ if (!video_device->flags.crt)
+ continue;
+ break;
+ case ACPI_VIDEO_DISPLAY_TV:
+ if (!video_device->flags.tvout)
+ continue;
+ break;
+ case ACPI_VIDEO_DISPLAY_DVI:
+ if (!video_device->flags.dvi)
+ continue;
+ break;
+ case ACPI_VIDEO_DISPLAY_LCD:
+ if (!video_device->flags.lcd)
+ continue;
+ break;
+ }
+ } else if (video_device->device_id != device_id) {
+ continue;
+ }
+
+ status = acpi_video_device_EDID(video_device, &buffer, length);
+
+ if (ACPI_FAILURE(status) || !buffer ||
+ buffer->type != ACPI_TYPE_BUFFER) {
+ length = 128;
+ status = acpi_video_device_EDID(video_device, &buffer,
+ length);
+ if (ACPI_FAILURE(status) || !buffer ||
+ buffer->type != ACPI_TYPE_BUFFER) {
+ continue;
+ }
+ }
+
+ *edid = buffer->buffer.pointer;
+ return length;
+ }
+
+ return -ENODEV;
+}
+EXPORT_SYMBOL(acpi_video_get_edid);
+
+static int
+acpi_video_bus_get_devices(struct acpi_video_bus *video,
+ struct acpi_device *device)
+{
+ int status = 0;
+ struct acpi_device *dev;
+
+ /*
+ * There are systems where video module known to work fine regardless
+ * of broken _DOD and ignoring returned value here doesn't cause
+ * any issues later.
+ */
+ acpi_video_device_enumerate(video);
+
+ list_for_each_entry(dev, &device->children, node) {
+
+ status = acpi_video_bus_get_one_device(dev, video);
+ if (status) {
+ dev_err(&dev->dev, "Can't attach device\n");
+ break;
+ }
+ video->child_count++;
+ }
+ return status;
+}
+
+/* acpi_video interface */
+
+/*
+ * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
+ * preform any automatic brightness change on receiving a notification.
+ */
+static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
+{
+ return acpi_video_bus_DOS(video, 0,
+ acpi_osi_is_win8() ? 1 : 0);
+}
+
+static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
+{
+ return acpi_video_bus_DOS(video, 0,
+ acpi_osi_is_win8() ? 0 : 1);
+}
+
+static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
+{
+ struct acpi_video_bus *video = acpi_driver_data(device);
+ struct input_dev *input;
+ int keycode = 0;
+
+ if (!video || !video->input)
+ return;
+
+ input = video->input;
+
+ switch (event) {
+ case ACPI_VIDEO_NOTIFY_SWITCH: /* User requested a switch,
+ * most likely via hotkey. */
+ keycode = KEY_SWITCHVIDEOMODE;
+ break;
+
+ case ACPI_VIDEO_NOTIFY_PROBE: /* User plugged in or removed a video
+ * connector. */
+ acpi_video_device_enumerate(video);
+ acpi_video_device_rebind(video);
+ keycode = KEY_SWITCHVIDEOMODE;
+ break;
+
+ case ACPI_VIDEO_NOTIFY_CYCLE: /* Cycle Display output hotkey pressed. */
+ keycode = KEY_SWITCHVIDEOMODE;
+ break;
+ case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT: /* Next Display output hotkey pressed. */
+ keycode = KEY_VIDEO_NEXT;
+ break;
+ case ACPI_VIDEO_NOTIFY_PREV_OUTPUT: /* previous Display output hotkey pressed. */
+ keycode = KEY_VIDEO_PREV;
+ break;
+
+ default:
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Unsupported event [0x%x]\n", event));
+ break;
+ }
+
+ if (acpi_notifier_call_chain(device, event, 0))
+ /* Something vetoed the keypress. */
+ keycode = 0;
+
+ if (keycode) {
+ input_report_key(input, keycode, 1);
+ input_sync(input);
+ input_report_key(input, keycode, 0);
+ input_sync(input);
+ }
+
+ return;
+}
+
+static void brightness_switch_event(struct acpi_video_device *video_device,
+ u32 event)
+{
+ if (!brightness_switch_enabled)
+ return;
+
+ video_device->switch_brightness_event = event;
+ schedule_delayed_work(&video_device->switch_brightness_work, HZ / 10);
+}
+
+static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
+{
+ struct acpi_video_device *video_device = data;
+ struct acpi_device *device = NULL;
+ struct acpi_video_bus *bus;
+ struct input_dev *input;
+ int keycode = 0;
+
+ if (!video_device)
+ return;
+
+ device = video_device->dev;
+ bus = video_device->video;
+ input = bus->input;
+
+ switch (event) {
+ case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS: /* Cycle brightness */
+ brightness_switch_event(video_device, event);
+ keycode = KEY_BRIGHTNESS_CYCLE;
+ break;
+ case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS: /* Increase brightness */
+ brightness_switch_event(video_device, event);
+ keycode = KEY_BRIGHTNESSUP;
+ break;
+ case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS: /* Decrease brightness */
+ brightness_switch_event(video_device, event);
+ keycode = KEY_BRIGHTNESSDOWN;
+ break;
+ case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
+ brightness_switch_event(video_device, event);
+ keycode = KEY_BRIGHTNESS_ZERO;
+ break;
+ case ACPI_VIDEO_NOTIFY_DISPLAY_OFF: /* display device off */
+ brightness_switch_event(video_device, event);
+ keycode = KEY_DISPLAY_OFF;
+ break;
+ default:
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Unsupported event [0x%x]\n", event));
+ break;
+ }
+
+ acpi_notifier_call_chain(device, event, 0);
+
+ if (keycode) {
+ input_report_key(input, keycode, 1);
+ input_sync(input);
+ input_report_key(input, keycode, 0);
+ input_sync(input);
+ }
+
+ return;
+}
+
+static int acpi_video_resume(struct notifier_block *nb,
+ unsigned long val, void *ign)
+{
+ struct acpi_video_bus *video;
+ struct acpi_video_device *video_device;
+ int i;
+
+ switch (val) {
+ case PM_HIBERNATION_PREPARE:
+ case PM_SUSPEND_PREPARE:
+ case PM_RESTORE_PREPARE:
+ return NOTIFY_DONE;
+ }
+
+ video = container_of(nb, struct acpi_video_bus, pm_nb);
+
+ dev_info(&video->device->dev, "Restoring backlight state\n");
+
+ for (i = 0; i < video->attached_count; i++) {
+ video_device = video->attached_array[i].bind_info;
+ if (video_device && video_device->brightness)
+ acpi_video_device_lcd_set_level(video_device,
+ video_device->brightness->curr);
+ }
+
+ return NOTIFY_OK;
+}
+
+static acpi_status
+acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
+ void **return_value)
+{
+ struct acpi_device *device = context;
+ struct acpi_device *sibling;
+ int result;
+
+ if (handle == device->handle)
+ return AE_CTRL_TERMINATE;
+
+ result = acpi_bus_get_device(handle, &sibling);
+ if (result)
+ return AE_OK;
+
+ if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
+ return AE_ALREADY_EXISTS;
+
+ return AE_OK;
+}
+
+static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
+{
+ struct backlight_properties props;
+ struct pci_dev *pdev;
+ acpi_handle acpi_parent;
+ struct device *parent = NULL;
+ int result;
+ static int count;
+ char *name;
+
+ /*
+ * Do not create backlight device for video output
+ * device that is not in the enumerated list.
+ */
+ if (!acpi_video_device_in_dod(device)) {
+ dev_dbg(&device->dev->dev, "not in _DOD list, ignore\n");
+ return;
+ }
+
+ result = acpi_video_init_brightness(device);
+ if (result)
+ return;
+
+ if (disable_backlight_sysfs_if > 0)
+ return;
+
+ name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
+ if (!name)
+ return;
+ count++;
+
+ acpi_get_parent(device->dev->handle, &acpi_parent);
+
+ pdev = acpi_get_pci_dev(acpi_parent);
+ if (pdev) {
+ parent = &pdev->dev;
+ pci_dev_put(pdev);
+ }
+
+ memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_FIRMWARE;
+ props.max_brightness = device->brightness->count - 3;
+ device->backlight = backlight_device_register(name,
+ parent,
+ device,
+ &acpi_backlight_ops,
+ &props);
+ kfree(name);
+ if (IS_ERR(device->backlight)) {
+ device->backlight = NULL;
+ return;
+ }
+
+ /*
+ * Save current brightness level in case we have to restore it
+ * before acpi_video_device_lcd_set_level() is called next time.
+ */
+ device->backlight->props.brightness =
+ acpi_video_get_brightness(device->backlight);
+
+ device->cooling_dev = thermal_cooling_device_register("LCD",
+ device->dev, &video_cooling_ops);
+ if (IS_ERR(device->cooling_dev)) {
+ /*
+ * Set cooling_dev to NULL so we don't crash trying to free it.
+ * Also, why the hell we are returning early and not attempt to
+ * register video output if cooling device registration failed?
+ * -- dtor
+ */
+ device->cooling_dev = NULL;
+ return;
+ }
+
+ dev_info(&device->dev->dev, "registered as cooling_device%d\n",
+ device->cooling_dev->id);
+ result = sysfs_create_link(&device->dev->dev.kobj,
+ &device->cooling_dev->device.kobj,
+ "thermal_cooling");
+ if (result)
+ printk(KERN_ERR PREFIX "Create sysfs link\n");
+ result = sysfs_create_link(&device->cooling_dev->device.kobj,
+ &device->dev->dev.kobj, "device");
+ if (result)
+ printk(KERN_ERR PREFIX "Create sysfs link\n");
+}
+
+static void acpi_video_run_bcl_for_osi(struct acpi_video_bus *video)
+{
+ struct acpi_video_device *dev;
+ union acpi_object *levels;
+
+ mutex_lock(&video->device_list_lock);
+ list_for_each_entry(dev, &video->video_device_list, entry) {
+ if (!acpi_video_device_lcd_query_levels(dev, &levels))
+ kfree(levels);
+ }
+ mutex_unlock(&video->device_list_lock);
+}
+
+static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
+{
+ struct acpi_video_device *dev;
+
+ if (video->backlight_registered)
+ return 0;
+
+ acpi_video_run_bcl_for_osi(video);
+
+ if (!acpi_video_verify_backlight_support())
+ return 0;
+
+ mutex_lock(&video->device_list_lock);
+ list_for_each_entry(dev, &video->video_device_list, entry)
+ acpi_video_dev_register_backlight(dev);
+ mutex_unlock(&video->device_list_lock);
+
+ video->backlight_registered = true;
+
+ video->pm_nb.notifier_call = acpi_video_resume;
+ video->pm_nb.priority = 0;
+ return register_pm_notifier(&video->pm_nb);
+}
+
+static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
+{
+ if (device->backlight) {
+ backlight_device_unregister(device->backlight);
+ device->backlight = NULL;
+ }
+ if (device->brightness) {
+ kfree(device->brightness->levels);
+ kfree(device->brightness);
+ device->brightness = NULL;
+ }
+ if (device->cooling_dev) {
+ sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
+ sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
+ thermal_cooling_device_unregister(device->cooling_dev);
+ device->cooling_dev = NULL;
+ }
+}
+
+static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
+{
+ struct acpi_video_device *dev;
+ int error;
+
+ if (!video->backlight_registered)
+ return 0;
+
+ error = unregister_pm_notifier(&video->pm_nb);
+
+ mutex_lock(&video->device_list_lock);
+ list_for_each_entry(dev, &video->video_device_list, entry)
+ acpi_video_dev_unregister_backlight(dev);
+ mutex_unlock(&video->device_list_lock);
+
+ video->backlight_registered = false;
+
+ return error;
+}
+
+static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
+{
+ acpi_status status;
+ struct acpi_device *adev = device->dev;
+
+ status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
+ acpi_video_device_notify, device);
+ if (ACPI_FAILURE(status))
+ dev_err(&adev->dev, "Error installing notify handler\n");
+ else
+ device->flags.notify = 1;
+}
+
+static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video)
+{
+ struct input_dev *input;
+ struct acpi_video_device *dev;
+ int error;
+
+ video->input = input = input_allocate_device();
+ if (!input) {
+ error = -ENOMEM;
+ goto out;
+ }
+
+ error = acpi_video_bus_start_devices(video);
+ if (error)
+ goto err_free_input;
+
+ snprintf(video->phys, sizeof(video->phys),
+ "%s/video/input0", acpi_device_hid(video->device));
+
+ input->name = acpi_device_name(video->device);
+ input->phys = video->phys;
+ input->id.bustype = BUS_HOST;
+ input->id.product = 0x06;
+ input->dev.parent = &video->device->dev;
+ input->evbit[0] = BIT(EV_KEY);
+ set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
+ set_bit(KEY_VIDEO_NEXT, input->keybit);
+ set_bit(KEY_VIDEO_PREV, input->keybit);
+ set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
+ set_bit(KEY_BRIGHTNESSUP, input->keybit);
+ set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
+ set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
+ set_bit(KEY_DISPLAY_OFF, input->keybit);
+
+ error = input_register_device(input);
+ if (error)
+ goto err_stop_dev;
+
+ mutex_lock(&video->device_list_lock);
+ list_for_each_entry(dev, &video->video_device_list, entry)
+ acpi_video_dev_add_notify_handler(dev);
+ mutex_unlock(&video->device_list_lock);
+
+ return 0;
+
+err_stop_dev:
+ acpi_video_bus_stop_devices(video);
+err_free_input:
+ input_free_device(input);
+ video->input = NULL;
+out:
+ return error;
+}
+
+static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
+{
+ if (dev->flags.notify) {
+ acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
+ acpi_video_device_notify);
+ dev->flags.notify = 0;
+ }
+}
+
+static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video)
+{
+ struct acpi_video_device *dev;
+
+ mutex_lock(&video->device_list_lock);
+ list_for_each_entry(dev, &video->video_device_list, entry)
+ acpi_video_dev_remove_notify_handler(dev);
+ mutex_unlock(&video->device_list_lock);
+
+ acpi_video_bus_stop_devices(video);
+ input_unregister_device(video->input);
+ video->input = NULL;
+}
+
+static int acpi_video_backlight_notify(struct notifier_block *nb,
+ unsigned long val, void *bd)
+{
+ struct backlight_device *backlight = bd;
+ struct acpi_video_bus *video;
+
+ /* acpi_video_verify_backlight_support only cares about raw devices */
+ if (backlight->props.type != BACKLIGHT_RAW)
+ return NOTIFY_DONE;
+
+ video = container_of(nb, struct acpi_video_bus, backlight_nb);
+
+ switch (val) {
+ case BACKLIGHT_REGISTERED:
+ if (!acpi_video_verify_backlight_support())
+ acpi_video_bus_unregister_backlight(video);
+ break;
+ case BACKLIGHT_UNREGISTERED:
+ acpi_video_bus_register_backlight(video);
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+static int acpi_video_bus_add_backlight_notify_handler(
+ struct acpi_video_bus *video)
+{
+ int error;
+
+ video->backlight_nb.notifier_call = acpi_video_backlight_notify;
+ video->backlight_nb.priority = 0;
+ error = backlight_register_notifier(&video->backlight_nb);
+ if (error == 0)
+ video->backlight_notifier_registered = true;
+
+ return error;
+}
+
+static int acpi_video_bus_remove_backlight_notify_handler(
+ struct acpi_video_bus *video)
+{
+ if (!video->backlight_notifier_registered)
+ return 0;
+
+ video->backlight_notifier_registered = false;
+
+ return backlight_unregister_notifier(&video->backlight_nb);
+}
+
+static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
+{
+ struct acpi_video_device *dev, *next;
+
+ mutex_lock(&video->device_list_lock);
+ list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
+ list_del(&dev->entry);
+ kfree(dev);
+ }
+ mutex_unlock(&video->device_list_lock);
+
+ return 0;
+}
+
+static int instance;
+
+static int acpi_video_bus_add(struct acpi_device *device)
+{
+ struct acpi_video_bus *video;
+ int error;
+ acpi_status status;
+
+ status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
+ device->parent->handle, 1,
+ acpi_video_bus_match, NULL,
+ device, NULL);
+ if (status == AE_ALREADY_EXISTS) {
+ printk(KERN_WARNING FW_BUG
+ "Duplicate ACPI video bus devices for the"
+ " same VGA controller, please try module "
+ "parameter \"video.allow_duplicates=1\""
+ "if the current driver doesn't work.\n");
+ if (!allow_duplicates)
+ return -ENODEV;
+ }
+
+ video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
+ if (!video)
+ return -ENOMEM;
+
+ /* a hack to fix the duplicate name "VID" problem on T61 */
+ if (!strcmp(device->pnp.bus_id, "VID")) {
+ if (instance)
+ device->pnp.bus_id[3] = '0' + instance;
+ instance++;
+ }
+ /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
+ if (!strcmp(device->pnp.bus_id, "VGA")) {
+ if (instance)
+ device->pnp.bus_id[3] = '0' + instance;
+ instance++;
+ }
+
+ video->device = device;
+ strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
+ strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
+ device->driver_data = video;
+
+ acpi_video_bus_find_cap(video);
+ error = acpi_video_bus_check(video);
+ if (error)
+ goto err_free_video;
+
+ mutex_init(&video->device_list_lock);
+ INIT_LIST_HEAD(&video->video_device_list);
+
+ error = acpi_video_bus_get_devices(video, device);
+ if (error)
+ goto err_put_video;
+
+ printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s rom: %s post: %s)\n",
+ ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
+ video->flags.multihead ? "yes" : "no",
+ video->flags.rom ? "yes" : "no",
+ video->flags.post ? "yes" : "no");
+ mutex_lock(&video_list_lock);
+ list_add_tail(&video->entry, &video_bus_head);
+ mutex_unlock(&video_list_lock);
+
+ acpi_video_bus_register_backlight(video);
+ acpi_video_bus_add_notify_handler(video);
+ acpi_video_bus_add_backlight_notify_handler(video);
+
+ return 0;
+
+err_put_video:
+ acpi_video_bus_put_devices(video);
+ kfree(video->attached_array);
+err_free_video:
+ kfree(video);
+ device->driver_data = NULL;
+
+ return error;
+}
+
+static int acpi_video_bus_remove(struct acpi_device *device)
+{
+ struct acpi_video_bus *video = NULL;
+
+
+ if (!device || !acpi_driver_data(device))
+ return -EINVAL;
+
+ video = acpi_driver_data(device);
+
+ acpi_video_bus_remove_backlight_notify_handler(video);
+ acpi_video_bus_remove_notify_handler(video);
+ acpi_video_bus_unregister_backlight(video);
+ acpi_video_bus_put_devices(video);
+
+ mutex_lock(&video_list_lock);
+ list_del(&video->entry);
+ mutex_unlock(&video_list_lock);
+
+ kfree(video->attached_array);
+ kfree(video);
+
+ return 0;
+}
+
+static int __init is_i740(struct pci_dev *dev)
+{
+ if (dev->device == 0x00D1)
+ return 1;
+ if (dev->device == 0x7000)
+ return 1;
+ return 0;
+}
+
+static int __init intel_opregion_present(void)
+{
+ int opregion = 0;
+ struct pci_dev *dev = NULL;
+ u32 address;
+
+ for_each_pci_dev(dev) {
+ if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
+ continue;
+ if (dev->vendor != PCI_VENDOR_ID_INTEL)
+ continue;
+ /* We don't want to poke around undefined i740 registers */
+ if (is_i740(dev))
+ continue;
+ pci_read_config_dword(dev, 0xfc, &address);
+ if (!address)
+ continue;
+ opregion = 1;
+ }
+ return opregion;
+}
+
+int acpi_video_register(void)
+{
+ int ret;
+
+ if (register_count) {
+ /*
+ * if the function of acpi_video_register is already called,
+ * don't register the acpi_vide_bus again and return no error.
+ */
+ return 0;
+ }
+
+ mutex_init(&video_list_lock);
+ INIT_LIST_HEAD(&video_bus_head);
+
+ ret = acpi_bus_register_driver(&acpi_video_bus);
+ if (ret)
+ return ret;
+
+ /*
+ * When the acpi_video_bus is loaded successfully, increase
+ * the counter reference.
+ */
+ register_count = 1;
+
+ return 0;
+}
+EXPORT_SYMBOL(acpi_video_register);
+
+void acpi_video_unregister(void)
+{
+ if (!register_count) {
+ /*
+ * If the acpi video bus is already unloaded, don't
+ * unload it again and return directly.
+ */
+ return;
+ }
+ acpi_bus_unregister_driver(&acpi_video_bus);
+
+ register_count = 0;
+
+ return;
+}
+EXPORT_SYMBOL(acpi_video_unregister);
+
+void acpi_video_unregister_backlight(void)
+{
+ struct acpi_video_bus *video;
+
+ if (!register_count)
+ return;
+
+ mutex_lock(&video_list_lock);
+ list_for_each_entry(video, &video_bus_head, entry)
+ acpi_video_bus_unregister_backlight(video);
+ mutex_unlock(&video_list_lock);
+}
+EXPORT_SYMBOL(acpi_video_unregister_backlight);
+
+/*
+ * This is kind of nasty. Hardware using Intel chipsets may require
+ * the video opregion code to be run first in order to initialise
+ * state before any ACPI video calls are made. To handle this we defer
+ * registration of the video class until the opregion code has run.
+ */
+
+static int __init acpi_video_init(void)
+{
+ /*
+ * Let the module load even if ACPI is disabled (e.g. due to
+ * a broken BIOS) so that i915.ko can still be loaded on such
+ * old systems without an AcpiOpRegion.
+ *
+ * acpi_video_register() will report -ENODEV later as well due
+ * to acpi_disabled when i915.ko tries to register itself afterwards.
+ */
+ if (acpi_disabled)
+ return 0;
+
+ dmi_check_system(video_dmi_table);
+
+ if (intel_opregion_present())
+ return 0;
+
+ return acpi_video_register();
+}
+
+static void __exit acpi_video_exit(void)
+{
+ acpi_video_unregister();
+
+ return;
+}
+
+module_init(acpi_video_init);
+module_exit(acpi_video_exit);
