diff options
author | Len Brown <len.brown@intel.com> | 2008-11-12 03:15:50 +0100 |
---|---|---|
committer | Len Brown <len.brown@intel.com> | 2008-11-12 03:15:50 +0100 |
commit | f398778aa336a2919ee04ba45d915007230c6957 (patch) | |
tree | c7244cd1d4af8d99c861b21ebcaeabf23e355b9f /drivers/acpi/video_detect.c | |
parent | Merge branch 'sysfs' into release (diff) | |
parent | thinkpad_acpi: fingers off backlight if video.ko is serving this functionality (diff) | |
download | linux-f398778aa336a2919ee04ba45d915007230c6957.tar.xz linux-f398778aa336a2919ee04ba45d915007230c6957.zip |
Merge branch 'video' into release
Conflicts:
Documentation/kernel-parameters.txt
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi/video_detect.c')
-rw-r--r-- | drivers/acpi/video_detect.c | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c new file mode 100644 index 000000000000..f022eb6f5637 --- /dev/null +++ b/drivers/acpi/video_detect.c @@ -0,0 +1,267 @@ +/* + * 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 + * assinged + * + * After PCI devices are glued with ACPI devices + * acpi_get_physical_pci_device() 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> + +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; + /* 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; + + /* Does 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; + + /* Does 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; + + /* Does 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, + &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 device *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_physical_pci_device(handle); + if (!dev) + return AE_OK; + put_device(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 + * summerized 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, + &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, + &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. + */ +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_OUTPUT_SWITCHING_FORCE_VIDEO; + } + return 1; +} +__setup("acpi_backlight=", acpi_backlight); + +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); |