/*
* Copyright (C) 2015 Red Hat Inc.
* Hans de Goede <hdegoede@redhat.com>
* Copyright (C) 2008 SuSE Linux Products GmbH
* Thomas Renninger <trenn@suse.de>
*
* May be copied or modified under the terms of the GNU General Public License
*
* video_detect.c:
* After PCI devices are glued with ACPI devices
* acpi_get_pci_dev() can be called to identify ACPI graphics
* devices for which a real graphics card is plugged in
*
* Depending on whether ACPI graphics extensions (cmp. ACPI spec Appendix B)
* are available, video.ko should be used to handle the device.
*
* Otherwise vendor specific drivers like thinkpad_acpi, asus-laptop,
* sony_acpi,... can take care about backlight brightness.
*
* Backlight drivers can use acpi_video_get_backlight_type() to determine
* which driver should handle the backlight.
*
* If CONFIG_ACPI_VIDEO is neither set as "compiled in" (y) nor as a module (m)
* this file will not be compiled and acpi_video_get_backlight_type() will
* always return acpi_backlight_vendor.
*/
#include <linux/export.h>
#include <linux/acpi.h>
#include <linux/backlight.h>
#include <linux/dmi.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/types.h>
#include <linux/workqueue.h>
#include <acpi/video.h>
ACPI_MODULE_NAME("video");
#define _COMPONENT ACPI_VIDEO_COMPONENT
void acpi_video_unregister_backlight(void);
static bool backlight_notifier_registered;
static struct notifier_block backlight_nb;
static struct work_struct backlight_notify_work;
static enum acpi_backlight_type acpi_backlight_cmdline = acpi_backlight_undef;
static enum acpi_backlight_type acpi_backlight_dmi = acpi_backlight_undef;
static void acpi_video_parse_cmdline(void)
{
if (!strcmp("vendor", acpi_video_backlight_string))
acpi_backlight_cmdline = acpi_backlight_vendor;
if (!strcmp("video", acpi_video_backlight_string))
acpi_backlight_cmdline = acpi_backlight_video;
if (!strcmp("native", acpi_video_backlight_string))
acpi_backlight_cmdline = acpi_backlight_native;
if (!strcmp("none", acpi_video_backlight_string))
acpi_backlight_cmdline = acpi_backlight_none;
}
static acpi_status
find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
{
long *cap = context;
struct pci_dev *dev;
struct acpi_device *acpi_dev;
static const struct acpi_device_id video_ids[] = {
{ACPI_VIDEO_HID, 0},
{"", 0},
};
if (acpi_bus_get_device(handle, &acpi_dev))
return AE_OK;
if (!acpi_match_device_ids(acpi_dev, video_ids)) {
dev = acpi_get_pci_dev(handle);
if (!dev)
return AE_OK;
pci_dev_put(dev);
*cap |= acpi_is_video_device(handle);
}
return AE_OK;
}
/* Force to use vendor driver when the ACPI device is known to be
* buggy */
static int video_detect_force_vendor(const struct dmi_system_id *d)
{
acpi_backlight_dmi = acpi_backlight_vendor;
return 0;
}
static int video_detect_force_video(const struct dmi_system_id *d)
{
acpi_backlight_dmi = acpi_backlight_video;
return 0;
}
static int video_detect_force_native(const struct dmi_system_id *d)
{
acpi_backlight_dmi = acpi_backlight_native;
return 0;
}
static const struct dmi_system_id video_detect_dmi_table[] = {
/* On Samsung X360, the BIOS will set a flag (VDRV) if generic
* ACPI backlight device is used. This flag will definitively break
* the backlight interface (even the vendor interface) untill next
* reboot. It's why we should prevent video.ko from being used here
* and we can't rely on a later call to acpi_video_unregister().
*/
{
.callback = video_detect_force_vendor,
.ident = "X360",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
DMI_MATCH(DMI_PRODUCT_NAME, "X360"),
DMI_MATCH(DMI_BOARD_NAME, "X360"),
},
},
{
.callback = video_detect_force_vendor,
.ident = "Asus UL30VT",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "UL30VT"),
},
},
{
.callback = video_detect_force_vendor,
.ident = "Asus UL30A",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
},
},
/*
* 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_detect_force_video,
.ident = "ThinkPad T420",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
},
},
{
.callback = video_detect_force_video,
.ident = "ThinkPad T520",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
},
},
{
.callback = video_detect_force_video,
.ident = "ThinkPad X201s",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
},
},
{
.callback = video_detect_force_video,
.ident = "ThinkPad X201T",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201T"),
},
},
/* The native backlight controls do not work on some older machines */
{
/* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
.callback = video_detect_force_video,
.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_detect_force_video,
.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_detect_force_video,
.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_detect_force_video,
.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_detect_force_video,
.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_detect_force_video,
.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=1272633 */
.callback = video_detect_force_video,
.ident = "Dell XPS14 L421X",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
},
},
{
/* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
.callback = video_detect_force_video,
.ident = "Dell XPS15 L521X",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
},
},
{
/* https://bugzilla.kernel.org/show_bug.cgi?id=108971 */
.callback = video_detect_force_video,
.ident = "SAMSUNG 530U4E/540U4E",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
DMI_MATCH(DMI_PRODUCT_NAME, "530U4E/540U4E"),
},
},
/* Non win8 machines which need native backlight nevertheless */
{
/* https://bugzilla.redhat.com/show_bug.cgi?id=1201530 */
.callback = video_detect_force_native,
.ident = "Lenovo Ideapad S405",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
DMI_MATCH(DMI_BOARD_NAME, "Lenovo IdeaPad S405"),
},
},
{
/* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
.callback = video_detect_force_native,
.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_detect_force_native,
.ident = "Apple MacBook Pro 12,1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
},
},
{
.callback = video_detect_force_native,
.ident = "Dell Vostro V131",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
},
},
{ },
};
/* This uses a workqueue to avoid various locking ordering issues */
static void acpi_video_backlight_notify_work(struct work_struct *work)
{
if (acpi_video_get_backlight_type() != acpi_backlight_video)
acpi_video_unregister_backlight();
}
static int acpi_video_backlight_notify(struct notifier_block *nb,
unsigned long val, void *bd)
{
struct backlight_device *backlight = bd;
/* A raw bl registering may change video -> native */
if (backlight->props.type == BACKLIGHT_RAW &&
val == BACKLIGHT_REGISTERED)
schedule_work(&backlight_notify_work);
return NOTIFY_OK;
}
/*
* Determine which type of backlight interface to use on this system,
* First check cmdline, then dmi quirks, then do autodetect.
*
* The autodetect order is:
* 1) Is the acpi-video backlight interface supported ->
* no, use a vendor interface
* 2) Is this a win8 "ready" BIOS and do we have a native interface ->
* yes, use a native interface
* 3) Else use the acpi-video interface
*
* Arguably the native on win8 check should be done first, but that would
* be a behavior change, which may causes issues.
*/
enum acpi_backlight_type acpi_video_get_backlight_type(void)
{
static DEFINE_MUTEX(init_mutex);
static bool init_done;
static long video_caps;
/* Parse cmdline, dmi and acpi only once */
mutex_lock(&init_mutex);
if (!init_done) {
acpi_video_parse_cmdline();
dmi_check_system(video_detect_dmi_table);
acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
ACPI_UINT32_MAX, find_video, NULL,
&video_caps, NULL);
INIT_WORK(&backlight_notify_work,
acpi_video_backlight_notify_work);
backlight_nb.notifier_call = acpi_video_backlight_notify;
backlight_nb.priority = 0;
if (backlight_register_notifier(&backlight_nb) == 0)
backlight_notifier_registered = true;
init_done = true;
}
mutex_unlock(&init_mutex);
if (acpi_backlight_cmdline != acpi_backlight_undef)
return acpi_backlight_cmdline;
if (acpi_backlight_dmi != acpi_backlight_undef)
return acpi_backlight_dmi;
if (!(video_caps & ACPI_VIDEO_BACKLIGHT))
return acpi_backlight_vendor;
if (acpi_osi_is_win8() && backlight_device_get_by_type(BACKLIGHT_RAW))
return acpi_backlight_native;
return acpi_backlight_video;
}
EXPORT_SYMBOL(acpi_video_get_backlight_type);
/*
* Set the preferred backlight interface type based on DMI info.
* This function allows DMI blacklists to be implemented by external
* platform drivers instead of putting a big blacklist in video_detect.c
*/
void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)
{
acpi_backlight_dmi = type;
/* Remove acpi-video backlight interface if it is no longer desired */
if (acpi_video_get_backlight_type() != acpi_backlight_video)
acpi_video_unregister_backlight();
}
EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type);
void __exit acpi_video_detect_exit(void)
{
if (backlight_notifier_registered)
backlight_unregister_notifier(&backlight_nb);
}
