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* [PATCH] viafb: correct sync polarity for OLPC DCON
@ 2011-11-21 15:05 Daniel Drake
  2011-11-23  6:53 ` Florian Tobias Schandinat
  0 siblings, 1 reply; 2+ messages in thread
From: Daniel Drake @ 2011-11-21 15:05 UTC (permalink / raw)
  To: linux-fbdev

While the OLPC display appears to be able to handle either positive
or negative sync, the Display Controller only recognises positive sync.

This brings viafb (for XO-1.5) in line with lxfb (for XO-1) and
fixes a recent regression where the XO-1.5 DCON could no longer be
frozen. Thanks to Florian Tobias Schandinat for helping identify
the fix.

Test case: from a vt,
	echo 1 > /sys/devices/platform/dcon/freeze
should cause the current screen contents to freeze, rather than garbage being
displayed.

Signed-off-by: Daniel Drake <dsd@laptop.org>
---
 drivers/video/via/share.h |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/video/via/share.h b/drivers/video/via/share.h
index 69d882c..c01c1c1 100644
--- a/drivers/video/via/share.h
+++ b/drivers/video/via/share.h
@@ -559,8 +559,8 @@
 #define M1200X720_R60_VSP       POSITIVE
 
 /* 1200x900@60 Sync Polarity (DCON) */
-#define M1200X900_R60_HSP       NEGATIVE
-#define M1200X900_R60_VSP       NEGATIVE
+#define M1200X900_R60_HSP       POSITIVE
+#define M1200X900_R60_VSP       POSITIVE
 
 /* 1280x600@60 Sync Polarity (GTF Mode) */
 #define M1280x600_R60_HSP       NEGATIVE
-- 
1.7.7.3


^ permalink raw reply related	[flat|nested] 2+ messages in thread

* Re: [PATCH] viafb: correct sync polarity for OLPC DCON
  2011-11-21 15:05 [PATCH] viafb: correct sync polarity for OLPC DCON Daniel Drake
@ 2011-11-23  6:53 ` Florian Tobias Schandinat
  0 siblings, 0 replies; 2+ messages in thread
From: Florian Tobias Schandinat @ 2011-11-23  6:53 UTC (permalink / raw)
  To: linux-fbdev

On 11/21/2011 03:05 PM, Daniel Drake wrote:
> While the OLPC display appears to be able to handle either positive
> or negative sync, the Display Controller only recognises positive sync.
> 
> This brings viafb (for XO-1.5) in line with lxfb (for XO-1) and
> fixes a recent regression where the XO-1.5 DCON could no longer be
> frozen. Thanks to Florian Tobias Schandinat for helping identify
> the fix.
> 
> Test case: from a vt,
> 	echo 1 > /sys/devices/platform/dcon/freeze
> should cause the current screen contents to freeze, rather than garbage being
> displayed.
> 
> Signed-off-by: Daniel Drake <dsd@laptop.org>

Applied.


Thanks,

Florian Tobias Schandinat

> ---
>  drivers/video/via/share.h |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/video/via/share.h b/drivers/video/via/share.h
> index 69d882c..c01c1c1 100644
> --- a/drivers/video/via/share.h
> +++ b/drivers/video/via/share.h
> @@ -559,8 +559,8 @@
>  #define M1200X720_R60_VSP       POSITIVE
>  
>  /* 1200x900@60 Sync Polarity (DCON) */
> -#define M1200X900_R60_HSP       NEGATIVE
> -#define M1200X900_R60_VSP       NEGATIVE
> +#define M1200X900_R60_HSP       POSITIVE
> +#define M1200X900_R60_VSP       POSITIVE
>  
>  /* 1280x600@60 Sync Polarity (GTF Mode) */
>  #define M1280x600_R60_HSP       NEGATIVE


^ permalink raw reply	[flat|nested] 2+ messages in thread

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2011-11-21 15:05 [PATCH] viafb: correct sync polarity for OLPC DCON Daniel Drake
2011-11-23  6:53 ` Florian Tobias Schandinat

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