[PATCH] ACPI video: ignore BIOS initial backlight value for HP 1000

[PATCH] ACPI video: ignore BIOS initial backlight value for HP 1000

[Alex Hung]

On HP 1000 lapops, BIOS reports minimum backlight on boot and
causes backlight to dim completely. This ignores the initial backlight
values and set to max brightness.

Buglink: https://bugs.launchpad.net/bugs/1167760

Signed-off-by: Alex Hung <alex.hung@canonical.com>
---
 drivers/acpi/video.c |    8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index c3932d0..5b32e15 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -456,6 +456,14 @@ static struct dmi_system_id video_dmi_table[] __initdata = {
 		DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dm4 Notebook PC"),
 		},
 	},
+	{
+	 .callback = video_ignore_initial_backlight,
+	 .ident = "HP 1000 Notebook PC",
+	 .matches = {
+		DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
+		DMI_MATCH(DMI_PRODUCT_NAME, "HP 1000 Notebook PC"),
+		},
+	},
 	{}
 };
 
-- 
1.7.9.5

Re: [PATCH] ACPI video: ignore BIOS initial backlight value for HP 1000

[Rafael J. Wysocki]

On Monday, May 06, 2013 04:23:43 PM Alex Hung wrote:
> On HP 1000 lapops, BIOS reports minimum backlight on boot and
> causes backlight to dim completely. This ignores the initial backlight
> values and set to max brightness.
> 
> Buglink: https://bugs.launchpad.net/bugs/1167760
> 
> Signed-off-by: Alex Hung <alex.hung@canonical.com>

Queued up for a post-3.10-rc1 push as 3.10 material.

Thanks,
Rafael


> ---
>  drivers/acpi/video.c |    8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
> index c3932d0..5b32e15 100644
> --- a/drivers/acpi/video.c
> +++ b/drivers/acpi/video.c
> @@ -456,6 +456,14 @@ static struct dmi_system_id video_dmi_table[] __initdata = {
>  		DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dm4 Notebook PC"),
>  		},
>  	},
> +	{
> +	 .callback = video_ignore_initial_backlight,
> +	 .ident = "HP 1000 Notebook PC",
> +	 .matches = {
> +		DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
> +		DMI_MATCH(DMI_PRODUCT_NAME, "HP 1000 Notebook PC"),
> +		},
> +	},
>  	{}
>  };
>  
> 
-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.

Re: [PATCH] ACPI video: ignore BIOS initial backlight value for HP 1000

[Aaron Lu]

On 05/06/2013 04:23 PM, Alex Hung wrote:
> On HP 1000 lapops, BIOS reports minimum backlight on boot and
> causes backlight to dim completely. This ignores the initial backlight
> values and set to max brightness.
> 
> Buglink: https://bugs.launchpad.net/bugs/1167760

I've checked the acpi dump from the bug page, it should be the same
firmware problem which the following patch is meant to solve:
http://www.spinics.net/lists/linux-acpi/msg47212.html

commit 2c62333a408f5badd2d2ffd7177f95deeccc5ca4
Author: Aaron Lu <aaron.lu@intel.com>
Date:   Wed Nov 6 09:07:10 2013 +0800

    ACPI / video: Quirk initial backlight level 0

Possible to give it a test? It's in Rafael's linux-next branch:
http://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git

If confirmed, we can save an entry in the DMI table.

Thanks,
Aaron

> 
> Signed-off-by: Alex Hung <alex.hung@canonical.com>
> ---
>  drivers/acpi/video.c |    8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
> index c3932d0..5b32e15 100644
> --- a/drivers/acpi/video.c
> +++ b/drivers/acpi/video.c
> @@ -456,6 +456,14 @@ static struct dmi_system_id video_dmi_table[] __initdata = {
>  		DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dm4 Notebook PC"),
>  		},
>  	},
> +	{
> +	 .callback = video_ignore_initial_backlight,
> +	 .ident = "HP 1000 Notebook PC",
> +	 .matches = {
> +		DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
> +		DMI_MATCH(Drjw@sisk.plMI_PRODUCT_NAME, "HP 1000 Notebook PC"),
> +		},
> +	},
>  	{}
>  };
>  
> 

Re: [PATCH] ACPI video: ignore BIOS initial backlight value for HP 1000

[Alex Hung]

Hi,

It works as expected.



On Tue, Nov 12, 2013 at 10:03 AM, Aaron Lu <aaron.lu@intel.com> wrote:
> On 05/06/2013 04:23 PM, Alex Hung wrote:
>> On HP 1000 lapops, BIOS reports minimum backlight on boot and
>> causes backlight to dim completely. This ignores the initial backlight
>> values and set to max brightness.
>>
>> Buglink: https://bugs.launchpad.net/bugs/1167760
>
> I've checked the acpi dump from the bug page, it should be the same
> firmware problem which the following patch is meant to solve:
> http://www.spinics.net/lists/linux-acpi/msg47212.html
>
> commit 2c62333a408f5badd2d2ffd7177f95deeccc5ca4
> Author: Aaron Lu <aaron.lu@intel.com>
> Date:   Wed Nov 6 09:07:10 2013 +0800
>
>     ACPI / video: Quirk initial backlight level 0
>
> Possible to give it a test? It's in Rafael's linux-next branch:
> http://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git
>
> If confirmed, we can save an entry in the DMI table.
>
> Thanks,
> Aaron
>
>>
>> Signed-off-by: Alex Hung <alex.hung@canonical.com>
>> ---
>>  drivers/acpi/video.c |    8 ++++++++
>>  1 file changed, 8 insertions(+)
>>
>> diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
>> index c3932d0..5b32e15 100644
>> --- a/drivers/acpi/video.c
>> +++ b/drivers/acpi/video.c
>> @@ -456,6 +456,14 @@ static struct dmi_system_id video_dmi_table[] __initdata = {
>>               DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dm4 Notebook PC"),
>>               },
>>       },
>> +     {
>> +      .callback = video_ignore_initial_backlight,
>> +      .ident = "HP 1000 Notebook PC",
>> +      .matches = {
>> +             DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
>> +             DMI_MATCH(Drjw@sisk.plMI_PRODUCT_NAME, "HP 1000 Notebook PC"),
>> +             },
>> +     },
>>       {}
>>  };
>>
>>
>



-- 
Cheers,
Alex Hung

More initial black screen system for removal from DMI table

[Aaron Lu]

On 11/13/2013 01:04 AM, Alex Hung wrote:
> Hi,
> 
> It works as expected.

Thanks for the confirm!

Now I look at the DMI table for initial backlight broken systems, in
addition to the "HP Pavilion m4" and "HP 1000 Notebook PC", the following
systems are also candidates for removal:
HP Pavilion g6 Notebook PC - bug 56661
HP Pavilion dm4 - no bug entry
Fujitsu E753 - bug 60161
HP Folio 13-2000 - bug 51141

I've checked the acpidump of all the above laptops except HP dm4, which
doesn't have a bug page, they all have the same problem we are
talking about here. The HP dm4 is very suspicious according to its
corresponding commit message and its brand.

I've asked in the individual bug page for test, once confirmed, I'll
remove them all.

Hi Gustavo,
Can you please test this? I've prepared a branch for you:
https://github.com/aaronlu/linux acpi_video_dmi
It is based on Rafael's linux-next branch, with only one patch
on top: remove all the above systems from the DMI table.

Thanks,
Aaron

> 
> 
> 
> On Tue, Nov 12, 2013 at 10:03 AM, Aaron Lu <aaron.lu@intel.com> wrote:
>> On 05/06/2013 04:23 PM, Alex Hung wrote:
>>> On HP 1000 lapops, BIOS reports minimum backlight on boot and
>>> causes backlight to dim completely. This ignores the initial backlight
>>> values and set to max brightness.
>>>
>>> Buglink: https://bugs.launchpad.net/bugs/1167760
>>
>> I've checked the acpi dump from the bug page, it should be the same
>> firmware problem which the following patch is meant to solve:
>> http://www.spinics.net/lists/linux-acpi/msg47212.html
>>
>> commit 2c62333a408f5badd2d2ffd7177f95deeccc5ca4
>> Author: Aaron Lu <aaron.lu@intel.com>
>> Date:   Wed Nov 6 09:07:10 2013 +0800
>>
>>     ACPI / video: Quirk initial backlight level 0
>>
>> Possible to give it a test? It's in Rafael's linux-next branch:
>> http://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git
>>
>> If confirmed, we can save an entry in the DMI table.
>>
>> Thanks,
>> Aaron
>>
>>>
>>> Signed-off-by: Alex Hung <alex.hung@canonical.com>
>>> ---
>>>  drivers/acpi/video.c |    8 ++++++++
>>>  1 file changed, 8 insertions(+)
>>>
>>> diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
>>> index c3932d0..5b32e15 100644
>>> --- a/drivers/acpi/video.c
>>> +++ b/drivers/acpi/video.c
>>> @@ -456,6 +456,14 @@ static struct dmi_system_id video_dmi_table[] __initdata = {
>>>               DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dm4 Notebook PC"),
>>>               },
>>>       },
>>> +     {
>>> +      .callback = video_ignore_initial_backlight,
>>> +      .ident = "HP 1000 Notebook PC",
>>> +      .matches = {
>>> +             DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
>>> +             DMI_MATCH(Drjw@sisk.plMI_PRODUCT_NAME, "HP 1000 Notebook PC"),
>>> +             },
>>> +     },
>>>       {}
>>>  };
>>>
>>>
>>
> 
> 
> 

Re: More initial black screen system for removal from DMI table

[Gustavo Maciel Dias Vieira]

Em Qua, 2013-11-13 às 10:07 +0800, Aaron Lu escreveu:
> Hi Gustavo,
> Can you please test this? I've prepared a branch for you:
> https://github.com/aaronlu/linux acpi_video_dmi
> It is based on Rafael's linux-next branch, with only one patch
> on top: remove all the above systems from the DMI table.

Aaron, thanks for setting the branch up. However, I will only be able to
test it over the weekend. 

For completeness my instance of the bug was (wrongly) tracked here:
https://bugs.freedesktop.org/show_bug.cgi?id=43577

Abraços,
Gustavo

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Re: More initial black screen system for removal from DMI table

[Aaron Lu]

On 11/14/2013 07:50 PM, Gustavo Maciel Dias Vieira wrote:
> Em Qua, 2013-11-13 às 10:07 +0800, Aaron Lu escreveu:
>> Hi Gustavo,
>> Can you please test this? I've prepared a branch for you:
>> https://github.com/aaronlu/linux acpi_video_dmi
>> It is based on Rafael's linux-next branch, with only one patch
>> on top: remove all the above systems from the DMI table.
> 
> Aaron, thanks for setting the branch up. However, I will only be able to
> test it over the weekend. 

No problem :-)

> 
> For completeness my instance of the bug was (wrongly) tracked here:
> https://bugs.freedesktop.org/show_bug.cgi?id=43577

Thanks for the info. Unfortunately, there isn't acpidump either.
Please attach the dump there when you have time, thanks.

As root:
# acpidump > acpidump.txt

-Aaron
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Re: More initial black screen system for removal from DMI table

[Gustavo Maciel Dias Vieira]

Em Sex, 2013-11-15 às 08:42 +0800, Aaron Lu escreveu:
> >> Can you please test this? I've prepared a branch for you:
> >> https://github.com/aaronlu/linux acpi_video_dmi
> >> It is based on Rafael's linux-next branch, with only one patch
> >> on top: remove all the above systems from the DMI table.

Tested and it works perfectly, no brightness regressions observed.

> > 
> > For completeness my instance of the bug was (wrongly) tracked here:
> > https://bugs.freedesktop.org/show_bug.cgi?id=43577
> 
> Thanks for the info. Unfortunately, there isn't acpidump either.
> Please attach the dump there when you have time, thanks.

Done

Abraços,
Gustavo

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Re: More initial black screen system for removal from DMI table

[Aaron Lu]

On 11/15/2013 09:17 AM, Gustavo Maciel Dias Vieira wrote:
> Em Sex, 2013-11-15 às 08:42 +0800, Aaron Lu escreveu:
>>>> Can you please test this? I've prepared a branch for you:
>>>> https://github.com/aaronlu/linux acpi_video_dmi
>>>> It is based on Rafael's linux-next branch, with only one patch
>>>> on top: remove all the above systems from the DMI table.
> 
> Tested and it works perfectly, no brightness regressions observed.

Thanks a lot for the test and info, I'll add your tested-by tag for that
patch if you don't mind.

-Aaron

> 
>>>
>>> For completeness my instance of the bug was (wrongly) tracked here:
>>> https://bugs.freedesktop.org/show_bug.cgi?id=43577
>>
>> Thanks for the info. Unfortunately, there isn't acpidump either.
>> Please attach the dump there when you have time, thanks.
> 
> Done
> 
> Abraços,
> Gustavo
> 

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Re: More initial black screen system for removal from DMI table

[Gustavo Maciel Dias Vieira]

Em Sex, 2013-11-15 às 09:31 +0800, Aaron Lu escreveu:
> >>>> Can you please test this? I've prepared a branch for you:
> >>>> https://github.com/aaronlu/linux acpi_video_dmi
> >>>> It is based on Rafael's linux-next branch, with only one patch
> >>>> on top: remove all the above systems from the DMI table.
> > 
> > Tested and it works perfectly, no brightness regressions observed.
> 
> Thanks a lot for the test and info, I'll add your tested-by tag for
> that
> patch if you don't mind.

Not at all, go ahead.

Abraços,
Gustavo


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[PATCH] ACPI / video: clean up DMI table for initial black screen problem

[Aaron Lu]

With commit 2c62333a408f "ACPI / video: Quirk initial backlight level 0"
we do not need to have the following systems in DMI table, so remove them.
HP Pavilion m4, HP 1000 Notebook PC, HP Pavilion g6 Notebook PC,
HP Pavilion dm4, Fujitsu E753, HP Folio 13-2000.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Alex Hung <alex.hung@canonical.com> # for HP 1000 Notebook PC
Tested-by: Gustavo Maciel Dias Vieira <gustavo@sagui.org> # for HP Pavilion dm4
---
Though I don't have test done for other models, their ACPI tables suggest
they have the same problem that should already be quirked by commit
2c62333a408f "ACPI / video: Quirk initial backlight level 0".

 drivers/acpi/video.c | 48 ------------------------------------------------
 1 file changed, 48 deletions(-)

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 18dbdff4656e..4ccb89e5c4ad 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -456,54 +456,6 @@ static struct dmi_system_id video_dmi_table[] __initdata = {
 		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
 		},
 	},
-	{
-	 .callback = video_ignore_initial_backlight,
-	 .ident = "HP Folio 13-2000",
-	 .matches = {
-		DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
-		DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13 - 2000 Notebook PC"),
-		},
-	},
-	{
-	 .callback = video_ignore_initial_backlight,
-	 .ident = "Fujitsu E753",
-	 .matches = {
-		DMI_MATCH(DMI_BOARD_VENDOR, "FUJITSU"),
-		DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E753"),
-		},
-	},
-	{
-	 .callback = video_ignore_initial_backlight,
-	 .ident = "HP Pavilion dm4",
-	 .matches = {
-		DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
-		DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dm4 Notebook PC"),
-		},
-	},
-	{
-	 .callback = video_ignore_initial_backlight,
-	 .ident = "HP Pavilion g6 Notebook PC",
-	 .matches = {
-		 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
-		 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion g6 Notebook PC"),
-		},
-	},
-	{
-	 .callback = video_ignore_initial_backlight,
-	 .ident = "HP 1000 Notebook PC",
-	 .matches = {
-		DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
-		DMI_MATCH(DMI_PRODUCT_NAME, "HP 1000 Notebook PC"),
-		},
-	},
-	{
-	 .callback = video_ignore_initial_backlight,
-	 .ident = "HP Pavilion m4",
-	 .matches = {
-		DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
-		DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion m4 Notebook PC"),
-		},
-	},
 	{}
 };
 
-- 
1.8.3.1

[PATCH v2] ACPI / video: clean up DMI table for initial black screen problem

[Aaron Lu]

With commit 2c62333a408f "ACPI / video: Quirk initial backlight level 0"
we do not need to have the following systems in DMI table, so remove them.
HP Pavilion m4, HP 1000 Notebook PC, HP Pavilion g6 Notebook PC,
HP Pavilion dm4, Fujitsu E753, HP Folio 13-2000.

With this change, the use_bios_initial_backlight module parameter is no
longer needed and thus removed.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Tested-by: Alex Hung <alex.hung@canonical.com> # for HP 1000 Notebook PC
Tested-by: Gustavo Maciel Dias Vieira <gustavo@sagui.org> # for HP Pavilion dm4
---
v2:
Remove use_bios_initial_backlight parameter and related code.

 drivers/acpi/video.c | 87 ++++++++--------------------------------------------
 1 file changed, 12 insertions(+), 75 deletions(-)

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 18dbdff4656e..995e91bcb97b 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -82,13 +82,6 @@ static bool allow_duplicates;
 module_param(allow_duplicates, bool, 0644);
 
 /*
- * Some BIOSes claim they use minimum backlight at boot,
- * and this may bring dimming screen after boot
- */
-static bool use_bios_initial_backlight = 1;
-module_param(use_bios_initial_backlight, bool, 0644);
-
-/*
  * For Windows 8 systems: if set ture and the GPU driver has
  * registered a backlight interface, skip registering ACPI video's.
  */
@@ -406,12 +399,6 @@ static int __init video_set_bqc_offset(const struct dmi_system_id *d)
 	return 0;
 }
 
-static int video_ignore_initial_backlight(const struct dmi_system_id *d)
-{
-	use_bios_initial_backlight = 0;
-	return 0;
-}
-
 static struct dmi_system_id video_dmi_table[] __initdata = {
 	/*
 	 * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
@@ -456,54 +443,6 @@ static struct dmi_system_id video_dmi_table[] __initdata = {
 		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
 		},
 	},
-	{
-	 .callback = video_ignore_initial_backlight,
-	 .ident = "HP Folio 13-2000",
-	 .matches = {
-		DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
-		DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13 - 2000 Notebook PC"),
-		},
-	},
-	{
-	 .callback = video_ignore_initial_backlight,
-	 .ident = "Fujitsu E753",
-	 .matches = {
-		DMI_MATCH(DMI_BOARD_VENDOR, "FUJITSU"),
-		DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E753"),
-		},
-	},
-	{
-	 .callback = video_ignore_initial_backlight,
-	 .ident = "HP Pavilion dm4",
-	 .matches = {
-		DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
-		DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dm4 Notebook PC"),
-		},
-	},
-	{
-	 .callback = video_ignore_initial_backlight,
-	 .ident = "HP Pavilion g6 Notebook PC",
-	 .matches = {
-		 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
-		 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion g6 Notebook PC"),
-		},
-	},
-	{
-	 .callback = video_ignore_initial_backlight,
-	 .ident = "HP 1000 Notebook PC",
-	 .matches = {
-		DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
-		DMI_MATCH(DMI_PRODUCT_NAME, "HP 1000 Notebook PC"),
-		},
-	},
-	{
-	 .callback = video_ignore_initial_backlight,
-	 .ident = "HP Pavilion m4",
-	 .matches = {
-		DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
-		DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion m4 Notebook PC"),
-		},
-	},
 	{}
 };
 
@@ -839,20 +778,18 @@ acpi_video_init_brightness(struct acpi_video_device *device)
 	if (!device->cap._BQC)
 		goto set_level;
 
-	if (use_bios_initial_backlight) {
-		level = acpi_video_bqc_value_to_level(device, level_old);
-		/*
-		 * On some buggy laptops, _BQC returns an uninitialized
-		 * value when invoked for the first time, i.e.
-		 * level_old is invalid (no matter whether it's a level
-		 * or an index). Set the backlight to max_level in this case.
-		 */
-		for (i = 2; i < br->count; i++)
-			if (level == br->levels[i])
-				break;
-		if (i == br->count || !level)
-			level = max_level;
-	}
+	level = acpi_video_bqc_value_to_level(device, level_old);
+	/*
+	 * On some buggy laptops, _BQC returns an uninitialized
+	 * value when invoked for the first time, i.e.
+	 * level_old is invalid (no matter whether it's a level
+	 * or an index). Set the backlight to max_level in this case.
+	 */
+	for (i = 2; i < br->count; i++)
+		if (level == br->levels[i])
+			break;
+	if (i == br->count || !level)
+		level = max_level;
 
 set_level:
 	result = acpi_video_device_lcd_set_level(device, level);
-- 
1.8.3.1

Re: [PATCH v2] ACPI / video: clean up DMI table for initial black screen problem

[Rafael J. Wysocki]

On Friday, November 15, 2013 02:39:12 PM Aaron Lu wrote:
> With commit 2c62333a408f "ACPI / video: Quirk initial backlight level 0"
> we do not need to have the following systems in DMI table, so remove them.
> HP Pavilion m4, HP 1000 Notebook PC, HP Pavilion g6 Notebook PC,
> HP Pavilion dm4, Fujitsu E753, HP Folio 13-2000.
> 
> With this change, the use_bios_initial_backlight module parameter is no
> longer needed and thus removed.
> 
> Signed-off-by: Aaron Lu <aaron.lu@intel.com>
> Tested-by: Alex Hung <alex.hung@canonical.com> # for HP 1000 Notebook PC
> Tested-by: Gustavo Maciel Dias Vieira <gustavo@sagui.org> # for HP Pavilion dm4

Queued up for the next ACPI pull request, thanks!

-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.