mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 01:10:04 +00:00
![Kamal Mostafa](/assets/img/avatar_default.png)
Make "acpi_backlight=video" param enable ACPI_VIDEO_BACKLIGHT_FORCE_VIDEO as intended, instead of incorrectly enabling video output switching. BugLink: http://bugs.launchpad.net/bugs/573120 Signed-off-by: Kamal Mostafa <kamal@canonical.com> Acked-by: Zhang Rui <rui.zhang@intel.com> Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: <stable@kernel.org> Acked-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
273 lines
8.5 KiB
C
273 lines
8.5 KiB
C
/*
|
|
* 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:
|
|
* Provides acpi_is_video_device() for early scanning of ACPI devices in scan.c
|
|
* There a Linux specific (Spec does not provide a HID for video devices) is
|
|
* assigned
|
|
*
|
|
* 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
|
|
*
|
|
* Now acpi_video_get_capabilities() can be called to check which
|
|
* capabilities the graphics cards plugged in support. The check for general
|
|
* video capabilities will be triggered by the first caller of
|
|
* acpi_video_get_capabilities(NULL); which will happen when the first
|
|
* backlight (or display output) switching supporting driver calls:
|
|
* acpi_video_backlight_support();
|
|
*
|
|
* 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_acpi,
|
|
* sony_acpi,... can take care about backlight brightness and display output
|
|
* switching.
|
|
*
|
|
* If CONFIG_ACPI_VIDEO is neither set as "compiled in" (y) nor as a module (m)
|
|
* this file will not be compiled, acpi_video_get_capabilities() and
|
|
* acpi_video_backlight_support() will always return 0 and vendor specific
|
|
* drivers always can handle backlight.
|
|
*
|
|
*/
|
|
|
|
#include <linux/acpi.h>
|
|
#include <linux/dmi.h>
|
|
#include <linux/pci.h>
|
|
|
|
#define PREFIX "ACPI: "
|
|
|
|
ACPI_MODULE_NAME("video");
|
|
#define _COMPONENT ACPI_VIDEO_COMPONENT
|
|
|
|
static long acpi_video_support;
|
|
static bool acpi_video_caps_checked;
|
|
|
|
static acpi_status
|
|
acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context,
|
|
void **retyurn_value)
|
|
{
|
|
long *cap = context;
|
|
acpi_handle h_dummy;
|
|
|
|
if (ACPI_SUCCESS(acpi_get_handle(handle, "_BCM", &h_dummy)) &&
|
|
ACPI_SUCCESS(acpi_get_handle(handle, "_BCL", &h_dummy))) {
|
|
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight "
|
|
"support\n"));
|
|
*cap |= ACPI_VIDEO_BACKLIGHT;
|
|
if (ACPI_FAILURE(acpi_get_handle(handle, "_BQC", &h_dummy)))
|
|
printk(KERN_WARNING FW_BUG PREFIX "ACPI brightness "
|
|
"control misses _BQC function\n");
|
|
/* We have backlight support, no need to scan further */
|
|
return AE_CTRL_TERMINATE;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* Returns true if the device is a video device which can be handled by
|
|
* video.ko.
|
|
* The device will get a Linux specific CID added in scan.c to
|
|
* identify the device as an ACPI graphics device
|
|
* Be aware that the graphics device may not be physically present
|
|
* Use acpi_video_get_capabilities() to detect general ACPI video
|
|
* capabilities of present cards
|
|
*/
|
|
long acpi_is_video_device(struct acpi_device *device)
|
|
{
|
|
acpi_handle h_dummy;
|
|
long video_caps = 0;
|
|
|
|
if (!device)
|
|
return 0;
|
|
|
|
/* Is this device able to support video switching ? */
|
|
if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOD", &h_dummy)) ||
|
|
ACPI_SUCCESS(acpi_get_handle(device->handle, "_DOS", &h_dummy)))
|
|
video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING;
|
|
|
|
/* Is this device able to retrieve a video ROM ? */
|
|
if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_ROM", &h_dummy)))
|
|
video_caps |= ACPI_VIDEO_ROM_AVAILABLE;
|
|
|
|
/* Is this device able to configure which video head to be POSTed ? */
|
|
if (ACPI_SUCCESS(acpi_get_handle(device->handle, "_VPO", &h_dummy)) &&
|
|
ACPI_SUCCESS(acpi_get_handle(device->handle, "_GPD", &h_dummy)) &&
|
|
ACPI_SUCCESS(acpi_get_handle(device->handle, "_SPD", &h_dummy)))
|
|
video_caps |= ACPI_VIDEO_DEVICE_POSTING;
|
|
|
|
/* Only check for backlight functionality if one of the above hit. */
|
|
if (video_caps)
|
|
acpi_walk_namespace(ACPI_TYPE_DEVICE, device->handle,
|
|
ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
|
|
&video_caps, NULL);
|
|
|
|
return video_caps;
|
|
}
|
|
EXPORT_SYMBOL(acpi_is_video_device);
|
|
|
|
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;
|
|
|
|
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(acpi_dev);
|
|
}
|
|
return AE_OK;
|
|
}
|
|
|
|
/*
|
|
* Returns the video capabilities of a specific ACPI graphics device
|
|
*
|
|
* if NULL is passed as argument all ACPI devices are enumerated and
|
|
* all graphics capabilities of physically present devices are
|
|
* summarized and returned. This is cached and done only once.
|
|
*/
|
|
long acpi_video_get_capabilities(acpi_handle graphics_handle)
|
|
{
|
|
long caps = 0;
|
|
struct acpi_device *tmp_dev;
|
|
acpi_status status;
|
|
|
|
if (acpi_video_caps_checked && graphics_handle == NULL)
|
|
return acpi_video_support;
|
|
|
|
if (!graphics_handle) {
|
|
/* Only do the global walk through all graphics devices once */
|
|
acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
|
|
ACPI_UINT32_MAX, find_video, NULL,
|
|
&caps, NULL);
|
|
/* There might be boot param flags set already... */
|
|
acpi_video_support |= caps;
|
|
acpi_video_caps_checked = 1;
|
|
/* Add blacklists here. Be careful to use the right *DMI* bits
|
|
* to still be able to override logic via boot params, e.g.:
|
|
*
|
|
* if (dmi_name_in_vendors("XY")) {
|
|
* acpi_video_support |=
|
|
* ACPI_VIDEO_OUTPUT_SWITCHING_DMI_VENDOR;
|
|
* acpi_video_support |=
|
|
* ACPI_VIDEO_BACKLIGHT_DMI_VENDOR;
|
|
*}
|
|
*/
|
|
} else {
|
|
status = acpi_bus_get_device(graphics_handle, &tmp_dev);
|
|
if (ACPI_FAILURE(status)) {
|
|
ACPI_EXCEPTION((AE_INFO, status, "Invalid device"));
|
|
return 0;
|
|
}
|
|
acpi_walk_namespace(ACPI_TYPE_DEVICE, graphics_handle,
|
|
ACPI_UINT32_MAX, find_video, NULL,
|
|
&caps, NULL);
|
|
}
|
|
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "We have 0x%lX video support %s %s\n",
|
|
graphics_handle ? caps : acpi_video_support,
|
|
graphics_handle ? "on device " : "in general",
|
|
graphics_handle ? acpi_device_bid(tmp_dev) : ""));
|
|
return caps;
|
|
}
|
|
EXPORT_SYMBOL(acpi_video_get_capabilities);
|
|
|
|
/* Returns true if video.ko can do backlight switching */
|
|
int acpi_video_backlight_support(void)
|
|
{
|
|
/*
|
|
* We must check whether the ACPI graphics device is physically plugged
|
|
* in. Therefore this must be called after binding PCI and ACPI devices
|
|
*/
|
|
if (!acpi_video_caps_checked)
|
|
acpi_video_get_capabilities(NULL);
|
|
|
|
/* First check for boot param -> highest prio */
|
|
if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_FORCE_VENDOR)
|
|
return 0;
|
|
else if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_FORCE_VIDEO)
|
|
return 1;
|
|
|
|
/* Then check for DMI blacklist -> second highest prio */
|
|
if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_DMI_VENDOR)
|
|
return 0;
|
|
else if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_DMI_VIDEO)
|
|
return 1;
|
|
|
|
/* Then go the default way */
|
|
return acpi_video_support & ACPI_VIDEO_BACKLIGHT;
|
|
}
|
|
EXPORT_SYMBOL(acpi_video_backlight_support);
|
|
|
|
/*
|
|
* Returns true if video.ko can do display output switching.
|
|
* This does not work well/at all with binary graphics drivers
|
|
* which disable system io ranges and do it on their own.
|
|
*/
|
|
int acpi_video_display_switch_support(void)
|
|
{
|
|
if (!acpi_video_caps_checked)
|
|
acpi_video_get_capabilities(NULL);
|
|
|
|
if (acpi_video_support & ACPI_VIDEO_OUTPUT_SWITCHING_FORCE_VENDOR)
|
|
return 0;
|
|
else if (acpi_video_support & ACPI_VIDEO_OUTPUT_SWITCHING_FORCE_VIDEO)
|
|
return 1;
|
|
|
|
if (acpi_video_support & ACPI_VIDEO_OUTPUT_SWITCHING_DMI_VENDOR)
|
|
return 0;
|
|
else if (acpi_video_support & ACPI_VIDEO_OUTPUT_SWITCHING_DMI_VIDEO)
|
|
return 1;
|
|
|
|
return acpi_video_support & ACPI_VIDEO_OUTPUT_SWITCHING;
|
|
}
|
|
EXPORT_SYMBOL(acpi_video_display_switch_support);
|
|
|
|
/*
|
|
* Use acpi_display_output=vendor/video or acpi_backlight=vendor/video
|
|
* To force that backlight or display output switching is processed by vendor
|
|
* specific acpi drivers or video.ko driver.
|
|
*/
|
|
static int __init acpi_backlight(char *str)
|
|
{
|
|
if (str == NULL || *str == '\0')
|
|
return 1;
|
|
else {
|
|
if (!strcmp("vendor", str))
|
|
acpi_video_support |=
|
|
ACPI_VIDEO_BACKLIGHT_FORCE_VENDOR;
|
|
if (!strcmp("video", str))
|
|
acpi_video_support |=
|
|
ACPI_VIDEO_BACKLIGHT_FORCE_VIDEO;
|
|
}
|
|
return 1;
|
|
}
|
|
__setup("acpi_backlight=", acpi_backlight);
|
|
|
|
static int __init acpi_display_output(char *str)
|
|
{
|
|
if (str == NULL || *str == '\0')
|
|
return 1;
|
|
else {
|
|
if (!strcmp("vendor", str))
|
|
acpi_video_support |=
|
|
ACPI_VIDEO_OUTPUT_SWITCHING_FORCE_VENDOR;
|
|
if (!strcmp("video", str))
|
|
acpi_video_support |=
|
|
ACPI_VIDEO_OUTPUT_SWITCHING_FORCE_VIDEO;
|
|
}
|
|
return 1;
|
|
}
|
|
__setup("acpi_display_output=", acpi_display_output);
|