[PATCH] ARM: mxs/tx28: fix up LCD pads

Subsystems: arm port, the rest

STALE5640d

6 messages, 3 authors, 2011-03-15 · open the first message on its own page

[PATCH] ARM: mxs/tx28: fix up LCD pads

From: Shawn Guo <hidden>
Date: 2011-03-05 16:27:20

* 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 <redacted>
---
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

[PATCH] ARM: mxs/tx28: fix up LCD pads

From: s.hauer@pengutronix.de (Sascha Hauer)
Date: 2011-03-07 07:34:00

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
quoted hunk
Signed-off-by: Shawn Guo <redacted>
---
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 |

[PATCH] ARM: mxs/tx28: fix up LCD pads

From: Lothar Waßmann <hidden>
Date: 2011-03-11 16:16:18

Hi,

Shawn Guo writes:
quoted hunk
* 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 <redacted>
---
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
___________________________________________________________

[PATCH] ARM: mxs/tx28: fix up LCD pads

From: Shawn Guo <hidden>
Date: 2011-03-15 02:32:49

On Fri, Mar 11, 2011 at 05:16:18PM +0100, Lothar Wa?mann wrote:
Hi,

Shawn Guo writes:
quoted
* 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 <redacted>
---
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?
quoted
-	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.
quoted
-	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?
quoted
 	MX28_PAD_LCD_RESET__GPIO_3_30 | LCD_MODE,
 	MX28_PAD_PWM0__PWM_0 | LCD_MODE,
 
-- 
Regards,
Shawn

[PATCH] ARM: mxs/tx28: fix up LCD pads

From: Lothar Waßmann <hidden>
Date: 2011-03-15 06:39:38

Hi,

Shawn Guo writes:
On Fri, Mar 11, 2011 at 05:16:18PM +0100, Lothar Wa?mann wrote:
quoted
Hi,

Shawn Guo writes:
quoted
* 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 <redacted>
---
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,
quoted
quoted
-	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.
quoted
-	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
___________________________________________________________

[PATCH] ARM: mxs/tx28: fix up LCD pads

From: Shawn Guo <hidden>
Date: 2011-03-15 07:33:06

On Tue, Mar 15, 2011 at 07:39:38AM +0100, Lothar Wa?mann wrote:
Hi,

Shawn Guo writes:
quoted
On Fri, Mar 11, 2011 at 05:16:18PM +0100, Lothar Wa?mann wrote:
quoted
Hi,

Shawn Guo writes:
quoted
* 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 <redacted>
---
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,
quoted
quoted
quoted
-	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.
quoted
-	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.
quoted
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
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