diff options
Diffstat (limited to 'kernel/drivers/acpi/video_detect.c')
| -rw-r--r-- | kernel/drivers/acpi/video_detect.c | 310 |
1 files changed, 310 insertions, 0 deletions
diff --git a/kernel/drivers/acpi/video_detect.c b/kernel/drivers/acpi/video_detect.c new file mode 100644 index 000000000..c42feb2ba --- /dev/null +++ b/kernel/drivers/acpi/video_detect.c @@ -0,0 +1,310 @@ +/* + * 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 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-laptop, + * sony_acpi,... can take care about backlight brightness. + * + * 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/export.h> +#include <linux/acpi.h> +#include <linux/dmi.h> +#include <linux/pci.h> + +#include "internal.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 **return_value) +{ + long *cap = context; + + if (acpi_has_method(handle, "_BCM") && + acpi_has_method(handle, "_BCL")) { + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight " + "support\n")); + *cap |= ACPI_VIDEO_BACKLIGHT; + if (!acpi_has_method(handle, "_BQC")) + printk(KERN_WARNING FW_BUG PREFIX "No _BQC method, " + "cannot determine initial brightness\n"); + /* We have backlight support, no need to scan further */ + return AE_CTRL_TERMINATE; + } + return 0; +} + +/* Returns true if the ACPI object 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(acpi_handle handle) +{ + long video_caps = 0; + + /* Is this device able to support video switching ? */ + if (acpi_has_method(handle, "_DOD") || acpi_has_method(handle, "_DOS")) + video_caps |= ACPI_VIDEO_OUTPUT_SWITCHING; + + /* Is this device able to retrieve a video ROM ? */ + if (acpi_has_method(handle, "_ROM")) + video_caps |= ACPI_VIDEO_ROM_AVAILABLE; + + /* Is this device able to configure which video head to be POSTed ? */ + if (acpi_has_method(handle, "_VPO") && + acpi_has_method(handle, "_GPD") && + acpi_has_method(handle, "_SPD")) + 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, 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(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_video_support |= ACPI_VIDEO_BACKLIGHT_DMI_VENDOR; + return 0; +} + +static 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"), + }, + }, + { + .callback = video_detect_force_vendor, + .ident = "Dell Inspiron 5737", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 5737"), + }, + }, + { }, +}; + +/* + * 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_BACKLIGHT_DMI_VENDOR; + *} + */ + + dmi_check_system(video_detect_dmi_table); + } 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); + +static void acpi_video_caps_check(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); +} + +bool acpi_osi_is_win8(void) +{ + return acpi_gbl_osi_data >= ACPI_OSI_WIN_8; +} +EXPORT_SYMBOL(acpi_osi_is_win8); + +/* Promote the vendor interface instead of the generic video module. + * This function allow DMI blacklists to be implemented by externals + * platform drivers instead of putting a big blacklist in video_detect.c + * After calling this function you will probably want to call + * acpi_video_unregister() to make sure the video module is not loaded + */ +void acpi_video_dmi_promote_vendor(void) +{ + acpi_video_caps_check(); + acpi_video_support |= ACPI_VIDEO_BACKLIGHT_DMI_VENDOR; +} +EXPORT_SYMBOL(acpi_video_dmi_promote_vendor); + +/* To be called when a driver who previously promoted the vendor + * interface */ +void acpi_video_dmi_demote_vendor(void) +{ + acpi_video_caps_check(); + acpi_video_support &= ~ACPI_VIDEO_BACKLIGHT_DMI_VENDOR; +} +EXPORT_SYMBOL(acpi_video_dmi_demote_vendor); + +/* Returns true if video.ko can do backlight switching */ +int acpi_video_backlight_support(void) +{ + acpi_video_caps_check(); + + /* 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); + +/* + * Use acpi_backlight=vendor/video to force that backlight 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); |