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acpi_video.c
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acpi_video.c
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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* video.c - ACPI Video Driver
*
* Copyright (C) 2004 Luming Yu <[email protected]>
* Copyright (C) 2004 Bruno Ducrot <[email protected]>
* Copyright (C) 2006 Thomas Tuttle <[email protected]>
*/
#define pr_fmt(fmt) "ACPI: video: " fmt
#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 <linux/uaccess.h>
#define ACPI_VIDEO_BUS_NAME "Video Bus"
#define ACPI_VIDEO_DEVICE_NAME "Video Device"
#define MAX_NAME_LEN 20
MODULE_AUTHOR("Bruno Ducrot");
MODULE_DESCRIPTION("ACPI Video Driver");
MODULE_LICENSE("GPL");
static bool brightness_switch_enabled = true;
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);
#define REPORT_OUTPUT_KEY_EVENTS 0x01
#define REPORT_BRIGHTNESS_KEY_EVENTS 0x02
static int report_key_events = -1;
module_param(report_key_events, int, 0644);
MODULE_PARM_DESC(report_key_events,
"0: none, 1: output changes, 2: brightness changes, 3: all");
static int hw_changes_brightness = -1;
module_param(hw_changes_brightness, int, 0644);
MODULE_PARM_DESC(hw_changes_brightness,
"Set this to 1 on buggy hw which changes the brightness itself when "
"a hotkey is pressed: -1: auto, 0: normal 1: hw-changes-brightness");
/*
* Whether the struct acpi_video_device_attrib::device_id_scheme bit should be
* assumed even if not actually set.
*/
static bool device_id_scheme = false;
module_param(device_id_scheme, bool, 0444);
static int only_lcd;
module_param(only_lcd, int, 0444);
static bool may_report_brightness_keys;
static int register_count;
static DEFINE_MUTEX(register_count_mutex);
static DEFINE_MUTEX(video_list_lock);
static LIST_HEAD(video_bus_head);
static int acpi_video_bus_add(struct acpi_device *device);
static void acpi_video_bus_remove(struct acpi_device *device);
static void acpi_video_bus_notify(acpi_handle handle, u32 event, void *data);
/*
* Indices in the _BCL method response: the first two items are special,
* the rest are all supported levels.
*
* See page 575 of the ACPI spec 3.0
*/
enum acpi_video_level_idx {
ACPI_VIDEO_AC_LEVEL, /* level when machine has full power */
ACPI_VIDEO_BATTERY_LEVEL, /* level when machine is on batteries */
ACPI_VIDEO_FIRST_LEVEL, /* actual supported levels begin here */
};
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,
},
};
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 */
/*
* The device ID might not actually follow the scheme described by this
* struct acpi_video_device_attrib. If it does, then this bit
* device_id_scheme is set; otherwise, other fields should be ignored.
*
* (but also see the global flag device_id_scheme)
*/
u32 device_id_scheme:1;
};
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;
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 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_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 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);
/* 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 = ACPI_VIDEO_FIRST_LEVEL; i < vd->brightness->count; i++) {
if (vd->brightness->levels[i] == cur_level)
return i - ACPI_VIDEO_FIRST_LEVEL;
}
return 0;
}
static int acpi_video_set_brightness(struct backlight_device *bd)
{
int request_level = bd->props.brightness + ACPI_VIDEO_FIRST_LEVEL;
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_video_device *video = cooling_dev->devdata;
*state = video->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
return 0;
}
static int video_get_cur_state(struct thermal_cooling_device *cooling_dev,
unsigned long *state)
{
struct acpi_video_device *video = cooling_dev->devdata;
unsigned long long level;
int offset;
if (acpi_video_device_lcd_get_level_current(video, &level, false))
return -EINVAL;
for (offset = ACPI_VIDEO_FIRST_LEVEL; 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_video_device *video = cooling_dev->devdata;
int level;
if (state >= video->brightness->count - ACPI_VIDEO_FIRST_LEVEL)
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(acpi_handle handle,
union acpi_object **levels)
{
int status;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
*levels = NULL;
status = acpi_evaluate_object(handle, "_BCL", NULL, &buffer);
if (ACPI_FAILURE(status))
return status;
obj = (union acpi_object *)buffer.pointer;
if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
acpi_handle_info(handle, "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_handle_info(device->dev->handle, "_BCM evaluation failed\n");
return -EIO;
}
device->brightness->curr = level;
for (state = ACPI_VIDEO_FIRST_LEVEL; state < device->brightness->count;
state++)
if (level == device->brightness->levels[state]) {
if (device->backlight)
device->backlight->props.brightness =
state - ACPI_VIDEO_FIRST_LEVEL;
return 0;
}
acpi_handle_info(device->dev->handle, "Current brightness invalid\n");
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 video_set_bqc_offset(const struct dmi_system_id *d)
{
bqc_offset_aml_bug_workaround = 9;
return 0;
}
static int video_set_device_id_scheme(const struct dmi_system_id *d)
{
device_id_scheme = true;
return 0;
}
static int video_enable_only_lcd(const struct dmi_system_id *d)
{
only_lcd = true;
return 0;
}
static int video_set_report_key_events(const struct dmi_system_id *id)
{
if (report_key_events == -1)
report_key_events = (uintptr_t)id->driver_data;
return 0;
}
static int video_hw_changes_brightness(
const struct dmi_system_id *d)
{
if (hw_changes_brightness == -1)
hw_changes_brightness = 1;
return 0;
}
static const struct dmi_system_id video_dmi_table[] = {
/*
* 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"),
},
},
/*
* Some machine's _DOD IDs don't have bit 31(Device ID Scheme) set
* but the IDs actually follow the Device ID Scheme.
*/
{
/* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
.callback = video_set_device_id_scheme,
.ident = "ESPRIMO Mobile M9410",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
},
},
/*
* Some machines have multiple video output devices, but only the one
* that is the type of LCD can do the backlight control so we should not
* register backlight interface for other video output devices.
*/
{
/* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
.callback = video_enable_only_lcd,
.ident = "ESPRIMO Mobile M9410",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
},
},
/*
* Some machines report wrong key events on the acpi-bus, suppress
* key event reporting on these. Note this is only intended to work
* around events which are plain wrong. In some cases we get double
* events, in this case acpi-video is considered the canonical source
* and the events from the other source should be filtered. E.g.
* by calling acpi_video_handles_brightness_key_presses() from the
* vendor acpi/wmi driver or by using /lib/udev/hwdb.d/60-keyboard.hwdb
*/
{
.callback = video_set_report_key_events,
.driver_data = (void *)((uintptr_t)REPORT_OUTPUT_KEY_EVENTS),
.ident = "Dell Vostro V131",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
},
},
{
.callback = video_set_report_key_events,
.driver_data = (void *)((uintptr_t)REPORT_BRIGHTNESS_KEY_EVENTS),
.ident = "Dell Vostro 3350",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "Vostro 3350"),
},
},
{
.callback = video_set_report_key_events,
.driver_data = (void *)((uintptr_t)REPORT_BRIGHTNESS_KEY_EVENTS),
.ident = "COLORFUL X15 AT 23",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "COLORFUL"),
DMI_MATCH(DMI_PRODUCT_NAME, "X15 AT 23"),
},
},
/*
* Some machines change the brightness themselves when a brightness
* hotkey gets pressed, despite us telling them not to. In this case
* acpi_video_device_notify() should only call backlight_force_update(
* BACKLIGHT_UPDATE_HOTKEY) and not do anything else.
*/
{
/* https://bugzilla.kernel.org/show_bug.cgi?id=204077 */
.callback = video_hw_changes_brightness,
.ident = "Packard Bell EasyNote MZ35",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Packard Bell"),
DMI_MATCH(DMI_PRODUCT_NAME, "EasyNote MZ35"),
},
},
{}
};
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 (see enum acpi_video_level_idx),
* so we need to compensate for that by offsetting ourselves
*/
if (device->brightness->flags._BCL_reversed)
bqc_value = device->brightness->count -
ACPI_VIDEO_FIRST_LEVEL - 1 - bqc_value;
level = device->brightness->levels[bqc_value +
ACPI_VIDEO_FIRST_LEVEL];
} 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 = ACPI_VIDEO_FIRST_LEVEL;
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_handle_info(device->dev->handle,
"%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_handle_info(device->dev->handle,
"%s evaluation 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 {
acpi_handle_info(device->dev->handle, "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 (ACPI appendix B)
* - a brightness hotkey gets pressed (implied by Win7/8 backlight docs)
* 1. The system BIOS should NOT automatically control the brightness
* level of the LCD when:
* - the power changes from AC to DC (ACPI appendix B)
* - a brightness hotkey gets pressed (implied by Win7/8 backlight docs)
* 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. However,
* there is a subtlety:
*
* If the _BCL package ordering is descending, the first level
* (br->levels[2]) is likely to be 0, and if the number of levels
* matches the number of steps, we might confuse a returned level to
* mean the index.
*
* For example:
*
* current_level = max_level = 100
* test_level = 0
* returned level = 100
*
* In this case 100 means the level, not the index, and _BCM failed.
* Still, if the _BCL package ordering is descending, the index of
* level 0 is also 100, so we assume _BQC is indexed, when it's not.
*
* This causes all _BQC calls to return bogus values causing weird
* behavior from the user's perspective. For example:
*
* xbacklight -set 10; xbacklight -set 20;
*
* would flash to 90% and then slowly down to the desired level (20).
*
* The solution is simple; test anything other than the first level
* (e.g. 1).
*/
test_level = current_level == max_level
? br->levels[ACPI_VIDEO_FIRST_LEVEL + 1]
: 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 - ACPI_VIDEO_FIRST_LEVEL - 1 - level;
if (br->levels[level + ACPI_VIDEO_FIRST_LEVEL] == test_level)
br->flags._BQC_use_index = 1;
}
if (!br->flags._BQC_use_index)
device->cap._BQC = device->cap._BCQ = 0;
}
return 0;
}
int acpi_video_get_levels(struct acpi_device *device,
struct acpi_video_device_brightness **dev_br,
int *pmax_level)
{
union acpi_object *obj = NULL;
int i, max_level = 0, count = 0, level_ac_battery = 0;
union acpi_object *o;
struct acpi_video_device_brightness *br = NULL;
int result = 0;
u32 value;
if (ACPI_FAILURE(acpi_video_device_lcd_query_levels(device->handle, &obj))) {
acpi_handle_debug(device->handle,
"Could not query available LCD brightness level\n");
result = -ENODEV;
goto out;
}
if (obj->package.count < ACPI_VIDEO_FIRST_LEVEL) {
result = -EINVAL;
goto out;
}
br = kzalloc(sizeof(*br), GFP_KERNEL);
if (!br) {
result = -ENOMEM;
goto out;
}
/*
* Note that we have to reserve 2 extra items (ACPI_VIDEO_FIRST_LEVEL),
* in order to account for buggy BIOS which don't export the first two
* special levels (see below)
*/
br->levels = kmalloc_array(obj->package.count + ACPI_VIDEO_FIRST_LEVEL,
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) {
acpi_handle_info(device->handle, "Invalid data\n");
continue;
}
value = (u32) o->integer.value;
/* Skip duplicate entries */
if (count > ACPI_VIDEO_FIRST_LEVEL
&& 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 = ACPI_VIDEO_FIRST_LEVEL; i < count; i++) {
if (br->levels[i] == br->levels[ACPI_VIDEO_AC_LEVEL])
level_ac_battery++;
if (br->levels[i] == br->levels[ACPI_VIDEO_BATTERY_LEVEL])
level_ac_battery++;
}
if (level_ac_battery < ACPI_VIDEO_FIRST_LEVEL) {
level_ac_battery = ACPI_VIDEO_FIRST_LEVEL - level_ac_battery;
br->flags._BCL_no_ac_battery_levels = 1;
for (i = (count - 1 + level_ac_battery);
i >= ACPI_VIDEO_FIRST_LEVEL; i--)
br->levels[i] = br->levels[i - level_ac_battery];
count += level_ac_battery;
} else if (level_ac_battery > ACPI_VIDEO_FIRST_LEVEL)
acpi_handle_info(device->handle,
"Too many duplicates in _BCL package");
/* Check if the _BCL package is in a reversed order */
if (max_level == br->levels[ACPI_VIDEO_FIRST_LEVEL]) {
br->flags._BCL_reversed = 1;
sort(&br->levels[ACPI_VIDEO_FIRST_LEVEL],
count - ACPI_VIDEO_FIRST_LEVEL,
sizeof(br->levels[ACPI_VIDEO_FIRST_LEVEL]),
acpi_video_cmp_level, NULL);
} else if (max_level != br->levels[count - 1])
acpi_handle_info(device->handle,
"Found unordered _BCL package");
br->count = count;
*dev_br = br;
if (pmax_level)
*pmax_level = max_level;
out:
kfree(obj);
return result;
out_free:
kfree(br);
goto out;
}
EXPORT_SYMBOL(acpi_video_get_levels);
/*
* 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)
{
int i, max_level = 0;
unsigned long long level, level_old;
struct acpi_video_device_brightness *br = NULL;
int result;
result = acpi_video_get_levels(device->dev, &br, &max_level);
if (result)
return result;
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 = ACPI_VIDEO_FIRST_LEVEL; 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_handle_debug(device->dev->handle, "found %d brightness levels\n",
br->count - ACPI_VIDEO_FIRST_LEVEL);
return 0;
out_free_levels:
kfree(br->levels);
kfree(br);
device->brightness = NULL;
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")) {
acpi_handle_info(device->dev->handle,
"_BCQ is used instead of _BQC\n");
device->cap._BCQ = 1;
}
if (acpi_has_method(device->dev->handle, "_DDC"))
device->cap._DDC = 1;
}
/*