--- /dev/null
+/*
+ * 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);
Code Review / kvmfornfv.git / blobdiff