On Wed, Jun 10, 2015 at 03:01:07PM +0200, Hans de Goede wrote:
Currently we have 2 kernel commandline options + dmi-quirks in 3 places all interacting (in interesting ways) to select which which backlight interface to use. On the commandline we've acpi_backlight=[video|vendor] and video.use_native_backlight=[0|1]. DMI quirks we have in acpi/video-detect.c, acpi/video.c and drivers/platform/x86/*.c .
This commit is the first step to cleaning this up, replacing the 2 cmdline options with just acpi_video.backlight=[video|vendor|native|none], and adding a new API to video_detect.c to reflect this.
I like backlight=[firmware|platform|raw|none] better, but that would require to put the selection/quirk logic to backlight core. What do you think?
Regards, Aaron
Follow up commits will also move other related code, like unregistering the acpi_video backlight interface if it was registered before other drivers which take priority over it are loaded, to video_detect.c where this logic really belongs.
Signed-off-by: Hans de Goede hdegoede@redhat.com
drivers/acpi/video_detect.c | 172 +++++++++++++++++++++----------------------- include/acpi/video.h | 17 +++++ 2 files changed, 100 insertions(+), 89 deletions(-)
diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c index 0bc8b98..01c8c46 100644 --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -1,4 +1,6 @@ /*
- Copyright (C) 2015 Red Hat Inc.
Hans de Goede <hdegoede@redhat.com>- Copyright (C) 2008 SuSE Linux Products GmbH
Thomas Renninger <trenn@suse.de>@@ -9,28 +11,24 @@
- 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.
- 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 <acpi/video.h> #include <linux/export.h> #include <linux/acpi.h> +#include <linux/backlight.h> #include <linux/dmi.h> #include <linux/module.h> #include <linux/pci.h> @@ -38,20 +36,24 @@ ACPI_MODULE_NAME("video"); #define _COMPONENT ACPI_VIDEO_COMPONENT
-static long acpi_video_support; -static bool acpi_video_caps_checked; +static enum acpi_backlight_type acpi_backlight_cmdline = acpi_backlight_undef; +static enum acpi_backlight_type acpi_backlight_dmi = acpi_backlight_undef;
static char acpi_backlight_str[16]; module_param_string(backlight, acpi_backlight_str, 16, 0444); MODULE_PARM_DESC(backlight,
- "Select which backlight interface to use [vendor|video]");
- "Select which backlight interface to use [vendor|video|native]");
static void acpi_video_parse_cmdline(void) { if (!strcmp("vendor", acpi_backlight_str))
acpi_video_support |= ACPI_VIDEO_BACKLIGHT_FORCE_VENDOR;
acpi_backlight_cmdline = acpi_backlight_vendor;
acpi_video_support |= ACPI_VIDEO_BACKLIGHT_FORCE_VIDEO;
acpi_backlight_cmdline = acpi_backlight_video;- if (!strcmp("native", acpi_backlight_str))
acpi_backlight_cmdline = acpi_backlight_native;- if (!strcmp("none", acpi_backlight_str))
acpi_backlight_cmdline = acpi_backlight_none;}
static acpi_status @@ -82,7 +84,7 @@ find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
- buggy */
static int video_detect_force_vendor(const struct dmi_system_id *d) {
- acpi_video_support |= ACPI_VIDEO_BACKLIGHT_DMI_VENDOR;
- acpi_backlight_dmi = acpi_backlight_vendor; return 0;
}
@@ -130,99 +132,91 @@ static struct dmi_system_id video_detect_dmi_table[] = { };
/*
- Returns the video capabilities of a specific ACPI graphics device
- Determine which type of backlight interface to use on this system,
- First check cmdline, then dmi quirks, then do autodetect.
- The autodetect order is:
- Is the acpi-video backlight interface supported ->
- no, use a vendor interface
- Is this a win8 "ready" BIOS and do we have a native interface ->
- yes, use a native interface
- Else use the acpi-video interface
- 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.
- Arguably the native on win8 check should be done first, but that would
*/
- be a behavior change, which may causes issues.
-static long acpi_video_get_capabilities(acpi_handle graphics_handle) +enum acpi_backlight_type acpi_video_get_backlight_type(void) {
- 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;*}*/
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);
- } 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_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, ACPI_UINT32_MAX, find_video, NULL,
&caps, NULL);
&video_caps, NULL);init_done = true;
- 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;
- 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_registered(BACKLIGHT_RAW))
return acpi_backlight_native;- return acpi_backlight_video;
} +EXPORT_SYMBOL(acpi_video_get_backlight_type);
-static void acpi_video_caps_check(void) +/*
- 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) {
- /*
* 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_parse_cmdline();acpi_video_get_capabilities(NULL);- }
- acpi_backlight_dmi = type;
} +EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type);
-/* 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
+/*
- Compatiblity function, this is going away as soon as all drivers are
- converted to acpi_video_set_dmi_backlight_type().
*/
- Promote the vendor interface instead of the generic video module.
- 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;
- acpi_video_set_dmi_backlight_type(acpi_backlight_vendor);
} EXPORT_SYMBOL(acpi_video_dmi_promote_vendor);
-/* Returns true if video.ko can do backlight switching */ +/*
- Compatiblity function, this is going away as soon as all drivers are
- converted to acpi_video_get_backlight_type().
- 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;
- /*
* This is done this way since vendor drivers call this to see* if they should load, and we do not want them to load for both* the acpi_backlight_video and acpi_backlight_native cases.*/- return acpi_video_get_backlight_type() != acpi_backlight_vendor;
} EXPORT_SYMBOL(acpi_video_backlight_support); diff --git a/include/acpi/video.h b/include/acpi/video.h index 843ef1a..01b5cc7 100644 --- a/include/acpi/video.h +++ b/include/acpi/video.h @@ -16,6 +16,14 @@ struct acpi_device; #define ACPI_VIDEO_DISPLAY_LEGACY_PANEL 0x0110 #define ACPI_VIDEO_DISPLAY_LEGACY_TV 0x0200
+enum acpi_backlight_type {
- acpi_backlight_undef = -1,
- acpi_backlight_none = 0,
- acpi_backlight_video,
- acpi_backlight_vendor,
- acpi_backlight_native,
+};
#if (defined CONFIG_ACPI_VIDEO || defined CONFIG_ACPI_VIDEO_MODULE) extern int acpi_video_register(void); extern void acpi_video_unregister(void); @@ -23,6 +31,8 @@ extern void acpi_video_unregister_backlight(void); extern int acpi_video_get_edid(struct acpi_device *device, int type, int device_id, void **edid); extern bool acpi_video_verify_backlight_support(void); +extern enum acpi_backlight_type acpi_video_get_backlight_type(void); +extern void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type); #else static inline int acpi_video_register(void) { return 0; } static inline void acpi_video_unregister(void) { return; } @@ -33,6 +43,13 @@ static inline int acpi_video_get_edid(struct acpi_device *device, int type, return -ENODEV; } static inline bool acpi_video_verify_backlight_support(void) { return false; } +static inline enum acpi_backlight_type acpi_video_get_backlight_type(void) +{
- return acpi_backlight_vendor;
+} +static void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type) +{ +} #endif
#endif
2.4.2
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