* [PATCH] ARM: mxs/tx28: fix up LCD pads
@ 2011-03-05 16:27 Shawn Guo
2011-03-07 7:34 ` Sascha Hauer
2011-03-11 16:16 ` Lothar Waßmann
0 siblings, 2 replies; 6+ messages in thread
From: Shawn Guo @ 2011-03-05 16:27 UTC (permalink / raw)
To: linux-arm-kernel
* In any case, LCD only needs one group of VSYNC, HSYNC, and DOTCLK.
So remove the redundant and useless one.
* LCD_ENABLE pad should not work as a GPIO for LCD, and there must be
one pad for ENABLE function.
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
---
Hi Lothar, Uwe,
I do not have the schematics of TX28 board, and I'm guessing the fix.
So it really needs your comments here.
Regards,
Shawn
arch/arm/mach-mxs/mach-tx28.c | 6 +-----
1 files changed, 1 insertions(+), 5 deletions(-)
diff --git a/arch/arm/mach-mxs/mach-tx28.c b/arch/arm/mach-mxs/mach-tx28.c
index b65e371..16a0059 100644
--- a/arch/arm/mach-mxs/mach-tx28.c
+++ b/arch/arm/mach-mxs/mach-tx28.c
@@ -61,11 +61,7 @@ static const iomux_cfg_t tx28_stk5v3_pads[] __initconst = {
MX28_PAD_LCD_RD_E__LCD_VSYNC | LCD_MODE,
MX28_PAD_LCD_WR_RWN__LCD_HSYNC | LCD_MODE,
MX28_PAD_LCD_RS__LCD_DOTCLK | LCD_MODE,
- MX28_PAD_LCD_CS__LCD_CS | LCD_MODE,
- MX28_PAD_LCD_VSYNC__LCD_VSYNC | LCD_MODE,
- MX28_PAD_LCD_HSYNC__LCD_HSYNC | LCD_MODE,
- MX28_PAD_LCD_DOTCLK__LCD_DOTCLK | LCD_MODE,
- MX28_PAD_LCD_ENABLE__GPIO_1_31 | LCD_MODE,
+ MX28_PAD_LCD_CS__LCD_ENABLE | LCD_MODE,
MX28_PAD_LCD_RESET__GPIO_3_30 | LCD_MODE,
MX28_PAD_PWM0__PWM_0 | LCD_MODE,
--
1.7.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH] ARM: mxs/tx28: fix up LCD pads
2011-03-05 16:27 [PATCH] ARM: mxs/tx28: fix up LCD pads Shawn Guo
@ 2011-03-07 7:34 ` Sascha Hauer
2011-03-11 16:16 ` Lothar Waßmann
1 sibling, 0 replies; 6+ messages in thread
From: Sascha Hauer @ 2011-03-07 7:34 UTC (permalink / raw)
To: linux-arm-kernel
On Sun, Mar 06, 2011 at 12:27:20AM +0800, Shawn Guo wrote:
> * In any case, LCD only needs one group of VSYNC, HSYNC, and DOTCLK.
> So remove the redundant and useless one.
> * LCD_ENABLE pad should not work as a GPIO for LCD, and there must be
> one pad for ENABLE function.
Thanks for pointing this out. I'll have a look into it.
Sascha
>
> Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
> ---
> Hi Lothar, Uwe,
>
> I do not have the schematics of TX28 board, and I'm guessing the fix.
> So it really needs your comments here.
>
> Regards,
> Shawn
>
> arch/arm/mach-mxs/mach-tx28.c | 6 +-----
> 1 files changed, 1 insertions(+), 5 deletions(-)
>
> diff --git a/arch/arm/mach-mxs/mach-tx28.c b/arch/arm/mach-mxs/mach-tx28.c
> index b65e371..16a0059 100644
> --- a/arch/arm/mach-mxs/mach-tx28.c
> +++ b/arch/arm/mach-mxs/mach-tx28.c
> @@ -61,11 +61,7 @@ static const iomux_cfg_t tx28_stk5v3_pads[] __initconst = {
> MX28_PAD_LCD_RD_E__LCD_VSYNC | LCD_MODE,
> MX28_PAD_LCD_WR_RWN__LCD_HSYNC | LCD_MODE,
> MX28_PAD_LCD_RS__LCD_DOTCLK | LCD_MODE,
> - MX28_PAD_LCD_CS__LCD_CS | LCD_MODE,
> - MX28_PAD_LCD_VSYNC__LCD_VSYNC | LCD_MODE,
> - MX28_PAD_LCD_HSYNC__LCD_HSYNC | LCD_MODE,
> - MX28_PAD_LCD_DOTCLK__LCD_DOTCLK | LCD_MODE,
> - MX28_PAD_LCD_ENABLE__GPIO_1_31 | LCD_MODE,
> + MX28_PAD_LCD_CS__LCD_ENABLE | LCD_MODE,
> MX28_PAD_LCD_RESET__GPIO_3_30 | LCD_MODE,
> MX28_PAD_PWM0__PWM_0 | LCD_MODE,
>
> --
> 1.7.1
>
>
>
--
Pengutronix e.K. | |
Industrial Linux Solutions | http://www.pengutronix.de/ |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH] ARM: mxs/tx28: fix up LCD pads
2011-03-05 16:27 [PATCH] ARM: mxs/tx28: fix up LCD pads Shawn Guo
2011-03-07 7:34 ` Sascha Hauer
@ 2011-03-11 16:16 ` Lothar Waßmann
2011-03-15 2:32 ` Shawn Guo
1 sibling, 1 reply; 6+ messages in thread
From: Lothar Waßmann @ 2011-03-11 16:16 UTC (permalink / raw)
To: linux-arm-kernel
Hi,
Shawn Guo writes:
> * In any case, LCD only needs one group of VSYNC, HSYNC, and DOTCLK.
> So remove the redundant and useless one.
> * LCD_ENABLE pad should not work as a GPIO for LCD, and there must be
> one pad for ENABLE function.
>
> Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
> ---
> Hi Lothar, Uwe,
>
> I do not have the schematics of TX28 board, and I'm guessing the fix.
> So it really needs your comments here.
>
> Regards,
> Shawn
>
> arch/arm/mach-mxs/mach-tx28.c | 6 +-----
> 1 files changed, 1 insertions(+), 5 deletions(-)
>
> diff --git a/arch/arm/mach-mxs/mach-tx28.c b/arch/arm/mach-mxs/mach-tx28.c
> index b65e371..16a0059 100644
> --- a/arch/arm/mach-mxs/mach-tx28.c
> +++ b/arch/arm/mach-mxs/mach-tx28.c
> @@ -61,11 +61,7 @@ static const iomux_cfg_t tx28_stk5v3_pads[] __initconst = {
> MX28_PAD_LCD_RD_E__LCD_VSYNC | LCD_MODE,
> MX28_PAD_LCD_WR_RWN__LCD_HSYNC | LCD_MODE,
> MX28_PAD_LCD_RS__LCD_DOTCLK | LCD_MODE,
> - MX28_PAD_LCD_CS__LCD_CS | LCD_MODE,
>
This one is correct as it stands (i.e. the suggested change is wrong).
> - MX28_PAD_LCD_VSYNC__LCD_VSYNC | LCD_MODE,
> - MX28_PAD_LCD_HSYNC__LCD_HSYNC | LCD_MODE,
> - MX28_PAD_LCD_DOTCLK__LCD_DOTCLK | LCD_MODE,
>
These should be removed from the pin list, as suggested.
> - MX28_PAD_LCD_ENABLE__GPIO_1_31 | LCD_MODE,
> + MX28_PAD_LCD_CS__LCD_ENABLE | LCD_MODE,
>
This change is also wrong. The pad is used as a (power) enable pin for
a certain family of LCDs that we recommend for use with our
modules. It should be configured as GPIO and pulled high/low whenever
the LCD is activated/deactivated (just like the LCD_RESET pad below).
> MX28_PAD_LCD_RESET__GPIO_3_30 | LCD_MODE,
> MX28_PAD_PWM0__PWM_0 | LCD_MODE,
>
Lothar Wa?mann
--
___________________________________________________________
Ka-Ro electronics GmbH | Pascalstra?e 22 | D - 52076 Aachen
Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10
Gesch?ftsf?hrer: Matthias Kaussen
Handelsregistereintrag: Amtsgericht Aachen, HRB 4996
www.karo-electronics.de | info at karo-electronics.de
___________________________________________________________
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH] ARM: mxs/tx28: fix up LCD pads
2011-03-11 16:16 ` Lothar Waßmann
@ 2011-03-15 2:32 ` Shawn Guo
2011-03-15 6:39 ` Lothar Waßmann
0 siblings, 1 reply; 6+ messages in thread
From: Shawn Guo @ 2011-03-15 2:32 UTC (permalink / raw)
To: linux-arm-kernel
On Fri, Mar 11, 2011 at 05:16:18PM +0100, Lothar Wa?mann wrote:
> Hi,
>
> Shawn Guo writes:
> > * In any case, LCD only needs one group of VSYNC, HSYNC, and DOTCLK.
> > So remove the redundant and useless one.
> > * LCD_ENABLE pad should not work as a GPIO for LCD, and there must be
> > one pad for ENABLE function.
> >
> > Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
> > ---
> > Hi Lothar, Uwe,
> >
> > I do not have the schematics of TX28 board, and I'm guessing the fix.
> > So it really needs your comments here.
> >
> > Regards,
> > Shawn
> >
> > arch/arm/mach-mxs/mach-tx28.c | 6 +-----
> > 1 files changed, 1 insertions(+), 5 deletions(-)
> >
> > diff --git a/arch/arm/mach-mxs/mach-tx28.c b/arch/arm/mach-mxs/mach-tx28.c
> > index b65e371..16a0059 100644
> > --- a/arch/arm/mach-mxs/mach-tx28.c
> > +++ b/arch/arm/mach-mxs/mach-tx28.c
> > @@ -61,11 +61,7 @@ static const iomux_cfg_t tx28_stk5v3_pads[] __initconst = {
> > MX28_PAD_LCD_RD_E__LCD_VSYNC | LCD_MODE,
> > MX28_PAD_LCD_WR_RWN__LCD_HSYNC | LCD_MODE,
> > MX28_PAD_LCD_RS__LCD_DOTCLK | LCD_MODE,
> > - MX28_PAD_LCD_CS__LCD_CS | LCD_MODE,
> >
> This one is correct as it stands (i.e. the suggested change is wrong).
>
So your panel is using LCD_CS without using LCD_RS as a couple?
> > - MX28_PAD_LCD_VSYNC__LCD_VSYNC | LCD_MODE,
> > - MX28_PAD_LCD_HSYNC__LCD_HSYNC | LCD_MODE,
> > - MX28_PAD_LCD_DOTCLK__LCD_DOTCLK | LCD_MODE,
> >
> These should be removed from the pin list, as suggested.
>
> > - MX28_PAD_LCD_ENABLE__GPIO_1_31 | LCD_MODE,
> > + MX28_PAD_LCD_CS__LCD_ENABLE | LCD_MODE,
> >
> This change is also wrong. The pad is used as a (power) enable pin for
> a certain family of LCDs that we recommend for use with our
> modules. It should be configured as GPIO and pulled high/low whenever
> the LCD is activated/deactivated (just like the LCD_RESET pad below).
>
This pad is not designed for a power enable pin but DATA_ENABLE
signal. Why does your panel need two power enable pins here, LCD_CS
and LCD_RESET?
> > MX28_PAD_LCD_RESET__GPIO_3_30 | LCD_MODE,
> > MX28_PAD_PWM0__PWM_0 | LCD_MODE,
> >
--
Regards,
Shawn
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH] ARM: mxs/tx28: fix up LCD pads
2011-03-15 2:32 ` Shawn Guo
@ 2011-03-15 6:39 ` Lothar Waßmann
2011-03-15 7:33 ` Shawn Guo
0 siblings, 1 reply; 6+ messages in thread
From: Lothar Waßmann @ 2011-03-15 6:39 UTC (permalink / raw)
To: linux-arm-kernel
Hi,
Shawn Guo writes:
> On Fri, Mar 11, 2011 at 05:16:18PM +0100, Lothar Wa?mann wrote:
> > Hi,
> >
> > Shawn Guo writes:
> > > * In any case, LCD only needs one group of VSYNC, HSYNC, and DOTCLK.
> > > So remove the redundant and useless one.
> > > * LCD_ENABLE pad should not work as a GPIO for LCD, and there must be
> > > one pad for ENABLE function.
> > >
> > > Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
> > > ---
> > > Hi Lothar, Uwe,
> > >
> > > I do not have the schematics of TX28 board, and I'm guessing the fix.
> > > So it really needs your comments here.
> > >
> > > Regards,
> > > Shawn
> > >
> > > arch/arm/mach-mxs/mach-tx28.c | 6 +-----
> > > 1 files changed, 1 insertions(+), 5 deletions(-)
> > >
> > > diff --git a/arch/arm/mach-mxs/mach-tx28.c b/arch/arm/mach-mxs/mach-tx28.c
> > > index b65e371..16a0059 100644
> > > --- a/arch/arm/mach-mxs/mach-tx28.c
> > > +++ b/arch/arm/mach-mxs/mach-tx28.c
> > > @@ -61,11 +61,7 @@ static const iomux_cfg_t tx28_stk5v3_pads[] __initconst = {
> > > MX28_PAD_LCD_RD_E__LCD_VSYNC | LCD_MODE,
> > > MX28_PAD_LCD_WR_RWN__LCD_HSYNC | LCD_MODE,
> > > MX28_PAD_LCD_RS__LCD_DOTCLK | LCD_MODE,
> > > - MX28_PAD_LCD_CS__LCD_CS | LCD_MODE,
> > >
> > This one is correct as it stands (i.e. the suggested change is wrong).
> >
> So your panel is using LCD_CS without using LCD_RS as a couple?
>
Sorry, I confused LCD_CS and LCD_ENABLE. It doesn't use LCD_CS, but
the LCD_ENABLE function on the LCD_CS pad. Thus, the pad should be
configured as:
MX28_PAD_LCD_CS__LCD_ENABLE | LCD_MODE,
> > > - MX28_PAD_LCD_VSYNC__LCD_VSYNC | LCD_MODE,
> > > - MX28_PAD_LCD_HSYNC__LCD_HSYNC | LCD_MODE,
> > > - MX28_PAD_LCD_DOTCLK__LCD_DOTCLK | LCD_MODE,
> > >
> > These should be removed from the pin list, as suggested.
> >
> > > - MX28_PAD_LCD_ENABLE__GPIO_1_31 | LCD_MODE,
> > > + MX28_PAD_LCD_CS__LCD_ENABLE | LCD_MODE,
> > >
> > This change is also wrong. The pad is used as a (power) enable pin for
> > a certain family of LCDs that we recommend for use with our
> > modules. It should be configured as GPIO and pulled high/low whenever
> > the LCD is activated/deactivated (just like the LCD_RESET pad below).
> >
> This pad is not designed for a power enable pin but DATA_ENABLE
>
It's also designed to be used as a GPIO, which is what we are doing.
> signal. Why does your panel need two power enable pins here, LCD_CS
> and LCD_RESET?
>
You should ask the manufacturer of the LCD panel. As far as I can tell
asserting LCD_RESET stops the LCD controller, while the pin connected
to the LCD_ENABLE pad enables the backlight (which can be controlled
further via a PWM input).
Lothar Wa?mann
--
___________________________________________________________
Ka-Ro electronics GmbH | Pascalstra?e 22 | D - 52076 Aachen
Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10
Gesch?ftsf?hrer: Matthias Kaussen
Handelsregistereintrag: Amtsgericht Aachen, HRB 4996
www.karo-electronics.de | info at karo-electronics.de
___________________________________________________________
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH] ARM: mxs/tx28: fix up LCD pads
2011-03-15 6:39 ` Lothar Waßmann
@ 2011-03-15 7:33 ` Shawn Guo
0 siblings, 0 replies; 6+ messages in thread
From: Shawn Guo @ 2011-03-15 7:33 UTC (permalink / raw)
To: linux-arm-kernel
On Tue, Mar 15, 2011 at 07:39:38AM +0100, Lothar Wa?mann wrote:
> Hi,
>
> Shawn Guo writes:
> > On Fri, Mar 11, 2011 at 05:16:18PM +0100, Lothar Wa?mann wrote:
> > > Hi,
> > >
> > > Shawn Guo writes:
> > > > * In any case, LCD only needs one group of VSYNC, HSYNC, and DOTCLK.
> > > > So remove the redundant and useless one.
> > > > * LCD_ENABLE pad should not work as a GPIO for LCD, and there must be
> > > > one pad for ENABLE function.
> > > >
> > > > Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
> > > > ---
> > > > Hi Lothar, Uwe,
> > > >
> > > > I do not have the schematics of TX28 board, and I'm guessing the fix.
> > > > So it really needs your comments here.
> > > >
> > > > Regards,
> > > > Shawn
> > > >
> > > > arch/arm/mach-mxs/mach-tx28.c | 6 +-----
> > > > 1 files changed, 1 insertions(+), 5 deletions(-)
> > > >
> > > > diff --git a/arch/arm/mach-mxs/mach-tx28.c b/arch/arm/mach-mxs/mach-tx28.c
> > > > index b65e371..16a0059 100644
> > > > --- a/arch/arm/mach-mxs/mach-tx28.c
> > > > +++ b/arch/arm/mach-mxs/mach-tx28.c
> > > > @@ -61,11 +61,7 @@ static const iomux_cfg_t tx28_stk5v3_pads[] __initconst = {
> > > > MX28_PAD_LCD_RD_E__LCD_VSYNC | LCD_MODE,
> > > > MX28_PAD_LCD_WR_RWN__LCD_HSYNC | LCD_MODE,
> > > > MX28_PAD_LCD_RS__LCD_DOTCLK | LCD_MODE,
> > > > - MX28_PAD_LCD_CS__LCD_CS | LCD_MODE,
> > > >
> > > This one is correct as it stands (i.e. the suggested change is wrong).
> > >
> > So your panel is using LCD_CS without using LCD_RS as a couple?
> >
> Sorry, I confused LCD_CS and LCD_ENABLE. It doesn't use LCD_CS, but
> the LCD_ENABLE function on the LCD_CS pad. Thus, the pad should be
> configured as:
> MX28_PAD_LCD_CS__LCD_ENABLE | LCD_MODE,
>
> > > > - MX28_PAD_LCD_VSYNC__LCD_VSYNC | LCD_MODE,
> > > > - MX28_PAD_LCD_HSYNC__LCD_HSYNC | LCD_MODE,
> > > > - MX28_PAD_LCD_DOTCLK__LCD_DOTCLK | LCD_MODE,
> > > >
> > > These should be removed from the pin list, as suggested.
> > >
> > > > - MX28_PAD_LCD_ENABLE__GPIO_1_31 | LCD_MODE,
> > > > + MX28_PAD_LCD_CS__LCD_ENABLE | LCD_MODE,
> > > >
> > > This change is also wrong. The pad is used as a (power) enable pin for
> > > a certain family of LCDs that we recommend for use with our
> > > modules. It should be configured as GPIO and pulled high/low whenever
> > > the LCD is activated/deactivated (just like the LCD_RESET pad below).
> > >
> > This pad is not designed for a power enable pin but DATA_ENABLE
> >
> It's also designed to be used as a GPIO, which is what we are doing.
>
> > signal. Why does your panel need two power enable pins here, LCD_CS
> > and LCD_RESET?
> >
> You should ask the manufacturer of the LCD panel. As far as I can tell
> asserting LCD_RESET stops the LCD controller, while the pin connected
> to the LCD_ENABLE pad enables the backlight (which can be controlled
> further via a PWM input).
>
It looks that we should have both lines.
MX28_PAD_LCD_CS__LCD_ENABLE | LCD_MODE,
MX28_PAD_LCD_ENABLE__GPIO_1_31 | LCD_MODE,
I was actually trying to draw attention with the patch. Would you
mind submitting a patch (with my Reported-by or SOB) to get it fixed
properly. After all, I do not have the board.
--
Regards,
Shawn
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2011-03-15 7:33 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2011-03-05 16:27 [PATCH] ARM: mxs/tx28: fix up LCD pads Shawn Guo
2011-03-07 7:34 ` Sascha Hauer
2011-03-11 16:16 ` Lothar Waßmann
2011-03-15 2:32 ` Shawn Guo
2011-03-15 6:39 ` Lothar Waßmann
2011-03-15 7:33 ` Shawn Guo
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