Bad _BQC behaviour on Packard Bell Easynot BG-45

Bad _BQC behaviour on Packard Bell Easynot BG-45

[Vladimir 'phcoder' Serbinenko]

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Hello. On the following model
	Manufacturer: Packard Bell BV
	Product Name: EasyNote_BG45-U-001CH
BQC returns a value between 0 and 15 but the brightness levels are
between 0 and 8. I could make a table of correspondance however I find
it too inflexible. So I propose the following patch which disables BQC
if it behaves badly

-- 
Regards
Vladimir 'phcoder' Serbinenko

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diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 1bdfb37..1735c34 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -594,6 +594,7 @@ acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
 					unsigned long long *level)
 {
 	acpi_status status = AE_OK;
+	int i;
 
 	if (device->cap._BQC || device->cap._BCQ) {
 		char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
@@ -609,8 +610,15 @@ acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
 
 			}
 			*level += bqc_offset_aml_bug_workaround;
-			device->brightness->curr = *level;
-			return 0;
+ 			for (i = 2; i < device->brightness->count; i++)
+ 			        if (device->brightness->levels[i] == *level) {
+ 				        device->brightness->curr = *level;
+ 			                return 0;
+ 			        }
+ 			/* BQC returned an invalid level. Stop using it.  */
+ 			ACPI_WARNING((AE_INFO, "%s returned an invalid level",
+ 				      buf));
+ 			device->cap._BQC = device->cap._BCQ = 0;
 		} else {
 			/* Fixme:
 			 * should we return an error or ignore this failure?

Re: Bad _BQC behaviour on Packard Bell Easynot BG-45

[Zhang Rui]

On Tue, 2009-06-09 at 23:19 +0800, Vladimir 'phcoder' Serbinenko wrote:
> Hello. On the following model
> 	Manufacturer: Packard Bell BV
> 	Product Name: EasyNote_BG45-U-001CH
> BQC returns a value between 0 and 15 but the brightness levels are
> between 0 and 8. I could make a table of correspondance however I find
> it too inflexible. So I propose the following patch which disables BQC
> if it behaves badly
> 
the patch seems good.
could you please send the acpidump of your laptop so that we can see if
there is any chance that we can enable the brightness control on this
laptop?

thanks,
rui

Re: Bad _BQC behaviour on Packard Bell Easynot BG-45

[Vladimir 'phcoder' Serbinenko]

On Wed, Jun 10, 2009 at 4:24 AM, Zhang Rui<rui.zhang@intel.com> wrote:
> On Tue, 2009-06-09 at 23:19 +0800, Vladimir 'phcoder' Serbinenko wrote:
>> Hello. On the following model
>>       Manufacturer: Packard Bell BV
>>       Product Name: EasyNote_BG45-U-001CH
>> BQC returns a value between 0 and 15 but the brightness levels are
>> between 0 and 8. I could make a table of correspondance however I find
>> it too inflexible. So I propose the following patch which disables BQC
>> if it behaves badly
>>
> the patch seems good.
> could you please send the acpidump of your laptop so that we can see if
> there is any chance that we can enable the brightness control on this
> laptop?
>
Is there any reason why this patch haven't been comitted?
> thanks,
> rui
>
>



-- 
Regards
Vladimir 'phcoder' Serbinenko

Personal git repository: http://repo.or.cz/w/grub2/phcoder.git
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Re: Bad _BQC behaviour on Packard Bell Easynot BG-45

[Zhang Rui]

On Fri, 2009-07-31 at 21:16 +0800, Vladimir 'phcoder' Serbinenko wrote:
> On Wed, Jun 10, 2009 at 4:24 AM, Zhang Rui<rui.zhang@intel.com> wrote:
> > On Tue, 2009-06-09 at 23:19 +0800, Vladimir 'phcoder' Serbinenko wrote:
> >> Hello. On the following model
> >>       Manufacturer: Packard Bell BV
> >>       Product Name: EasyNote_BG45-U-001CH
> >> BQC returns a value between 0 and 15 but the brightness levels are
> >> between 0 and 8. I could make a table of correspondance however I find
> >> it too inflexible. So I propose the following patch which disables BQC
> >> if it behaves badly
> >>
> > the patch seems good.
> > could you please send the acpidump of your laptop so that we can see if
> > there is any chance that we can enable the brightness control on this
> > laptop?
> >
> Is there any reason why this patch haven't been comitted?

well, len is on vacation.
he'll be back by this week. :)

> > thanks,
> > rui
> >
> >
> 
> 
>