Re: [PATCH v2 3/3] ACPI / video: Do not register backlight if win8 and native interface exists
On 09/20/2013 04:36 PM, Jani Nikula wrote:
> On Tue, 17 Sep 2013, Aaron Lu wrote:
>> According to Matthew Garrett, "Windows 8 leaves backlight control up
>> to individual graphics drivers rather than making ACPI calls itself.
>> There's plenty of evidence to suggest that the Intel driver for
>> Windows 8 doesn't use the ACPI interface, including the fact that
>> it's broken on a bunch of machines when the OS claims to support
>> Windows 8. The simplest thing to do appears to be to disable the
>> ACPI backlight interface on these systems".
>>
>> So for Win8 systems, if there is native backlight control interface
>> registered by GPU driver, ACPI video will not register its own. For
>> users who prefer to keep ACPI video's backlight interface, the existing
>> kernel cmdline option acpi_backlight=video can be used.
>>
>> This patch is an evolution from previous work done by Matthew Garrett,
>> Chun-Yi Lee, Seth Forshee and Rafael J. Wysocki.
>>
>> Signed-off-by: Aaron Lu
>> ---
>> drivers/acpi/internal.h | 5 ++---
>> drivers/acpi/video.c| 27 +--
>> drivers/acpi/video_detect.c | 14 --
>> 3 files changed, 19 insertions(+), 27 deletions(-)
>>
>> diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
>> index 20f4233..453ae8d 100644
>> --- a/drivers/acpi/internal.h
>> +++ b/drivers/acpi/internal.h
>> @@ -169,9 +169,8 @@ int acpi_create_platform_device(struct acpi_device *adev,
>> Video
>>
>> -- */
>> #if defined(CONFIG_ACPI_VIDEO) || defined(CONFIG_ACPI_VIDEO_MODULE)
>> -bool acpi_video_backlight_quirks(void);
>> -#else
>> -static inline bool acpi_video_backlight_quirks(void) { return false; }
>> +bool acpi_osi_is_win8(void);
>> +bool acpi_video_verify_backlight_support(void);
>> #endif
>>
>> #endif /* _ACPI_INTERNAL_H_ */
>> diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
>> index 5ad5a71..343db59 100644
>> --- a/drivers/acpi/video.c
>> +++ b/drivers/acpi/video.c
>> @@ -1256,8 +1256,8 @@ acpi_video_switch_brightness(struct acpi_video_device
>> *device, int event)
>> unsigned long long level_current, level_next;
>> int result = -EINVAL;
>>
>> -/* no warning message if acpi_backlight=vendor is used */
>> -if (!acpi_video_backlight_support())
>> +/* no warning message if acpi_backlight=vendor or a quirk is used */
>> +if (!acpi_video_verify_backlight_support())
>> return 0;
>>
>> if (!device->brightness)
>> @@ -1386,13 +1386,13 @@ acpi_video_bus_get_devices(struct acpi_video_bus
>> *video,
>> static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
>> {
>> return acpi_video_bus_DOS(video, 0,
>> - acpi_video_backlight_quirks() ? 1 : 0);
>> + acpi_osi_is_win8() ? 1 : 0);
>> }
>>
>> static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
>> {
>> return acpi_video_bus_DOS(video, 0,
>> - acpi_video_backlight_quirks() ? 0 : 1);
>> + acpi_osi_is_win8() ? 0 : 1);
>> }
>>
>> static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
>> @@ -1558,7 +1558,7 @@ acpi_video_bus_match(acpi_handle handle, u32 level,
>> void *context,
>>
>> static void acpi_video_dev_register_backlight(struct acpi_video_device
>> *device)
>> {
>> -if (acpi_video_backlight_support()) {
>> +if (acpi_video_verify_backlight_support()) {
>> struct backlight_properties props;
>> struct pci_dev *pdev;
>> acpi_handle acpi_parent;
>> @@ -1677,23 +1677,6 @@ static int acpi_video_bus_unregister_backlight(struct
>> acpi_video_bus *video)
>> return error;
>> }
>>
>> -int acpi_video_unregister_backlight(void)
>> -{
>> -struct acpi_video_bus *video;
>> -int error = 0;
>> -
>> -mutex_lock(&video_list_lock);
>> -list_for_each_entry(video, &video_bus_head, entry) {
>> -error = acpi_video_bus_unregister_backlight(video);
>> -if (error)
>> -break;
>> -}
>> -mutex_unlock(&video_list_lock);
>> -
>> -return error;
>> -}
>> -EXPORT_SYMBOL(acpi_video_unregister_backlight);
>
> You add this in patch 2/3 only to remove it again in 3/3?
This is a mistake while I'm preparing the patches, I'll fix it in next
revision, thanks for pointing this out.
>
>> -
>> static void acpi_video_dev_add_notify_handler(struct acpi_video_device
>> *device)
>> {
>> acpi_status status;
>> diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c
>> index 940edbf..23d7d26 100644
>> --- a/drivers/acpi/video_detect.c
>> +++ b/drivers/acpi/video_detect.c
>> @@ -37,6 +37,7 @@
>> #include
>> #include
>> #include
>> +#include
>>
>> #include "internal.h"
>>
>> @@ -233,11 +234,11 @@ static void acpi_video_caps_check(void)
>>
Re: [PATCH v2 3/3] ACPI / video: Do not register backlight if win8 and native interface exists
On mar., 2013-09-17 at 17:23 +0800, Aaron Lu wrote: > According to Matthew Garrett, "Windows 8 leaves backlight control up > to individual graphics drivers rather than making ACPI calls itself. > There's plenty of evidence to suggest that the Intel driver for > Windows 8 doesn't use the ACPI interface, including the fact that > it's broken on a bunch of machines when the OS claims to support > Windows 8. The simplest thing to do appears to be to disable the > ACPI backlight interface on these systems". > > So for Win8 systems, if there is native backlight control interface > registered by GPU driver, ACPI video will not register its own. For > users who prefer to keep ACPI video's backlight interface, the > existing > kernel cmdline option acpi_backlight=video can be used. > > This patch is an evolution from previous work done by Matthew Garrett, > Chun-Yi Lee, Seth Forshee and Rafael J. Wysocki. > > Signed-off-by: Aaron Lu Tested-by: Yves-Alexis Perez -- Yves-Alexis signature.asc Description: This is a digitally signed message part
Re: [PATCH v2 3/3] ACPI / video: Do not register backlight if win8 and native interface exists
On Tue, 17 Sep 2013, Aaron Lu wrote:
> According to Matthew Garrett, "Windows 8 leaves backlight control up
> to individual graphics drivers rather than making ACPI calls itself.
> There's plenty of evidence to suggest that the Intel driver for
> Windows 8 doesn't use the ACPI interface, including the fact that
> it's broken on a bunch of machines when the OS claims to support
> Windows 8. The simplest thing to do appears to be to disable the
> ACPI backlight interface on these systems".
>
> So for Win8 systems, if there is native backlight control interface
> registered by GPU driver, ACPI video will not register its own. For
> users who prefer to keep ACPI video's backlight interface, the existing
> kernel cmdline option acpi_backlight=video can be used.
>
> This patch is an evolution from previous work done by Matthew Garrett,
> Chun-Yi Lee, Seth Forshee and Rafael J. Wysocki.
>
> Signed-off-by: Aaron Lu
> ---
> drivers/acpi/internal.h | 5 ++---
> drivers/acpi/video.c| 27 +--
> drivers/acpi/video_detect.c | 14 --
> 3 files changed, 19 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
> index 20f4233..453ae8d 100644
> --- a/drivers/acpi/internal.h
> +++ b/drivers/acpi/internal.h
> @@ -169,9 +169,8 @@ int acpi_create_platform_device(struct acpi_device *adev,
> Video
>--
> */
> #if defined(CONFIG_ACPI_VIDEO) || defined(CONFIG_ACPI_VIDEO_MODULE)
> -bool acpi_video_backlight_quirks(void);
> -#else
> -static inline bool acpi_video_backlight_quirks(void) { return false; }
> +bool acpi_osi_is_win8(void);
> +bool acpi_video_verify_backlight_support(void);
> #endif
>
> #endif /* _ACPI_INTERNAL_H_ */
> diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
> index 5ad5a71..343db59 100644
> --- a/drivers/acpi/video.c
> +++ b/drivers/acpi/video.c
> @@ -1256,8 +1256,8 @@ acpi_video_switch_brightness(struct acpi_video_device
> *device, int event)
> unsigned long long level_current, level_next;
> int result = -EINVAL;
>
> - /* no warning message if acpi_backlight=vendor is used */
> - if (!acpi_video_backlight_support())
> + /* no warning message if acpi_backlight=vendor or a quirk is used */
> + if (!acpi_video_verify_backlight_support())
> return 0;
>
> if (!device->brightness)
> @@ -1386,13 +1386,13 @@ acpi_video_bus_get_devices(struct acpi_video_bus
> *video,
> static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
> {
> return acpi_video_bus_DOS(video, 0,
> - acpi_video_backlight_quirks() ? 1 : 0);
> + acpi_osi_is_win8() ? 1 : 0);
> }
>
> static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
> {
> return acpi_video_bus_DOS(video, 0,
> - acpi_video_backlight_quirks() ? 0 : 1);
> + acpi_osi_is_win8() ? 0 : 1);
> }
>
> static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
> @@ -1558,7 +1558,7 @@ acpi_video_bus_match(acpi_handle handle, u32 level,
> void *context,
>
> static void acpi_video_dev_register_backlight(struct acpi_video_device
> *device)
> {
> - if (acpi_video_backlight_support()) {
> + if (acpi_video_verify_backlight_support()) {
> struct backlight_properties props;
> struct pci_dev *pdev;
> acpi_handle acpi_parent;
> @@ -1677,23 +1677,6 @@ static int acpi_video_bus_unregister_backlight(struct
> acpi_video_bus *video)
> return error;
> }
>
> -int acpi_video_unregister_backlight(void)
> -{
> - struct acpi_video_bus *video;
> - int error = 0;
> -
> - mutex_lock(&video_list_lock);
> - list_for_each_entry(video, &video_bus_head, entry) {
> - error = acpi_video_bus_unregister_backlight(video);
> - if (error)
> - break;
> - }
> - mutex_unlock(&video_list_lock);
> -
> - return error;
> -}
> -EXPORT_SYMBOL(acpi_video_unregister_backlight);
You add this in patch 2/3 only to remove it again in 3/3?
> -
> static void acpi_video_dev_add_notify_handler(struct acpi_video_device
> *device)
> {
> acpi_status status;
> diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c
> index 940edbf..23d7d26 100644
> --- a/drivers/acpi/video_detect.c
> +++ b/drivers/acpi/video_detect.c
> @@ -37,6 +37,7 @@
> #include
> #include
> #include
> +#include
>
> #include "internal.h"
>
> @@ -233,11 +234,11 @@ static void acpi_video_caps_check(void)
> acpi_video_get_capabilities(NULL);
> }
>
> -bool acpi_video_backlight_quirks(void)
> +bool acpi_osi_is_win8(void)
> {
> return acpi_gbl_osi_data >= ACPI_OSI_WIN_8;
> }
> -EXPORT_SYMBOL(acpi_video_backlight_quirks);
> +EXPORT_SYMBOL(acp
Re: [PATCH v2 3/3] ACPI / video: Do not register backlight if win8 and native interface exists
On Tue, 2013-09-17 at 17:23 +0800, Aaron Lu wrote: > According to Matthew Garrett, "Windows 8 leaves backlight control up > to individual graphics drivers rather than making ACPI calls itself. > There's plenty of evidence to suggest that the Intel driver for > Windows 8 doesn't use the ACPI interface, including the fact that > it's broken on a bunch of machines when the OS claims to support > Windows 8. The simplest thing to do appears to be to disable the > ACPI backlight interface on these systems". > > So for Win8 systems, if there is native backlight control interface > registered by GPU driver, ACPI video will not register its own. For > users who prefer to keep ACPI video's backlight interface, the existing > kernel cmdline option acpi_backlight=video can be used. > > This patch is an evolution from previous work done by Matthew Garrett, > Chun-Yi Lee, Seth Forshee and Rafael J. Wysocki. > > Signed-off-by: Aaron Lu Tested-by: Igor Gnatenko > --- > drivers/acpi/internal.h | 5 ++--- > drivers/acpi/video.c| 27 +-- > drivers/acpi/video_detect.c | 14 -- > 3 files changed, 19 insertions(+), 27 deletions(-) -- Igor Gnatenko Fedora release 20 (Heisenbug) Linux 3.12.0-0.rc1.git0.1.fc20.x86_64 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH v2 3/3] ACPI / video: Do not register backlight if win8 and native interface exists
According to Matthew Garrett, "Windows 8 leaves backlight control up
to individual graphics drivers rather than making ACPI calls itself.
There's plenty of evidence to suggest that the Intel driver for
Windows 8 doesn't use the ACPI interface, including the fact that
it's broken on a bunch of machines when the OS claims to support
Windows 8. The simplest thing to do appears to be to disable the
ACPI backlight interface on these systems".
So for Win8 systems, if there is native backlight control interface
registered by GPU driver, ACPI video will not register its own. For
users who prefer to keep ACPI video's backlight interface, the existing
kernel cmdline option acpi_backlight=video can be used.
This patch is an evolution from previous work done by Matthew Garrett,
Chun-Yi Lee, Seth Forshee and Rafael J. Wysocki.
Signed-off-by: Aaron Lu
---
drivers/acpi/internal.h | 5 ++---
drivers/acpi/video.c| 27 +--
drivers/acpi/video_detect.c | 14 --
3 files changed, 19 insertions(+), 27 deletions(-)
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index 20f4233..453ae8d 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -169,9 +169,8 @@ int acpi_create_platform_device(struct acpi_device *adev,
Video
-- */
#if defined(CONFIG_ACPI_VIDEO) || defined(CONFIG_ACPI_VIDEO_MODULE)
-bool acpi_video_backlight_quirks(void);
-#else
-static inline bool acpi_video_backlight_quirks(void) { return false; }
+bool acpi_osi_is_win8(void);
+bool acpi_video_verify_backlight_support(void);
#endif
#endif /* _ACPI_INTERNAL_H_ */
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 5ad5a71..343db59 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -1256,8 +1256,8 @@ acpi_video_switch_brightness(struct acpi_video_device
*device, int event)
unsigned long long level_current, level_next;
int result = -EINVAL;
- /* no warning message if acpi_backlight=vendor is used */
- if (!acpi_video_backlight_support())
+ /* no warning message if acpi_backlight=vendor or a quirk is used */
+ if (!acpi_video_verify_backlight_support())
return 0;
if (!device->brightness)
@@ -1386,13 +1386,13 @@ acpi_video_bus_get_devices(struct acpi_video_bus *video,
static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
{
return acpi_video_bus_DOS(video, 0,
- acpi_video_backlight_quirks() ? 1 : 0);
+ acpi_osi_is_win8() ? 1 : 0);
}
static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
{
return acpi_video_bus_DOS(video, 0,
- acpi_video_backlight_quirks() ? 0 : 1);
+ acpi_osi_is_win8() ? 0 : 1);
}
static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
@@ -1558,7 +1558,7 @@ acpi_video_bus_match(acpi_handle handle, u32 level, void
*context,
static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
{
- if (acpi_video_backlight_support()) {
+ if (acpi_video_verify_backlight_support()) {
struct backlight_properties props;
struct pci_dev *pdev;
acpi_handle acpi_parent;
@@ -1677,23 +1677,6 @@ static int acpi_video_bus_unregister_backlight(struct
acpi_video_bus *video)
return error;
}
-int acpi_video_unregister_backlight(void)
-{
- struct acpi_video_bus *video;
- int error = 0;
-
- mutex_lock(&video_list_lock);
- list_for_each_entry(video, &video_bus_head, entry) {
- error = acpi_video_bus_unregister_backlight(video);
- if (error)
- break;
- }
- mutex_unlock(&video_list_lock);
-
- return error;
-}
-EXPORT_SYMBOL(acpi_video_unregister_backlight);
-
static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
{
acpi_status status;
diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c
index 940edbf..23d7d26 100644
--- a/drivers/acpi/video_detect.c
+++ b/drivers/acpi/video_detect.c
@@ -37,6 +37,7 @@
#include
#include
#include
+#include
#include "internal.h"
@@ -233,11 +234,11 @@ static void acpi_video_caps_check(void)
acpi_video_get_capabilities(NULL);
}
-bool acpi_video_backlight_quirks(void)
+bool acpi_osi_is_win8(void)
{
return acpi_gbl_osi_data >= ACPI_OSI_WIN_8;
}
-EXPORT_SYMBOL(acpi_video_backlight_quirks);
+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
@@ -283,6 +284,15 @@ int acpi_video_backlight_support(void)
}
EXPORT_SYMBOL(acpi_video_backlight_support);
+bool acpi_video_verify_bac
