ARM: dts: at91: Reenable UART TX pull-ups

Commit Message

Ingo van Lil Dec. 3, 2019, 2:21 p.m. UTC

Pull-ups for SAM9 UART/USART TX lines were disabled in a previous
commit. However, several chips in the SAM9 family require pull-ups to
prevent the TX lines from falling (and causing an endless break
condition) when the transceiver is disabled.

From the SAM9G20 datasheet, 32.5.1: "To prevent the TXD line from
falling when the USART is disabled, the use of an internal pull up
is mandatory.". This commit reenables the pull-ups for all chips having
that sentence in their datasheets.

Fixes: 5e04822f7db5 ("ARM: dts: at91: fixes uart pinctrl, set pullup on rx, clear pullup on tx")
Signed-off-by: Ingo van Lil <[e-mail]>
Cc: Peter Rosin <[e-mail]>
---
 arch/arm/boot/dts/at91sam9260.dtsi | 12 ++++++------
 arch/arm/boot/dts/at91sam9261.dtsi |  6 +++---
 arch/arm/boot/dts/at91sam9263.dtsi |  6 +++---
 arch/arm/boot/dts/at91sam9g45.dtsi |  8 ++++----
 arch/arm/boot/dts/at91sam9rl.dtsi  |  8 ++++----
 5 files changed, 20 insertions(+), 20 deletions(-)

--
2.21.0

Comments

Alexandre Belloni Dec. 10, 2019, 10:57 a.m. UTC | #1

On 03/12/2019 15:21:47+0100, Ingo van Lil wrote:
> Pull-ups for SAM9 UART/USART TX lines were disabled in a previous
> commit. However, several chips in the SAM9 family require pull-ups to
> prevent the TX lines from falling (and causing an endless break
> condition) when the transceiver is disabled.
> 
> From the SAM9G20 datasheet, 32.5.1: "To prevent the TXD line from
> falling when the USART is disabled, the use of an internal pull up
> is mandatory.". This commit reenables the pull-ups for all chips having
> that sentence in their datasheets.
> 
> Fixes: 5e04822f7db5 ("ARM: dts: at91: fixes uart pinctrl, set pullup on rx, clear pullup on tx")
> Signed-off-by: Ingo van Lil <[e-mail]>
> Cc: Peter Rosin <[e-mail]>
> ---
>  arch/arm/boot/dts/at91sam9260.dtsi | 12 ++++++------
>  arch/arm/boot/dts/at91sam9261.dtsi |  6 +++---
>  arch/arm/boot/dts/at91sam9263.dtsi |  6 +++---
>  arch/arm/boot/dts/at91sam9g45.dtsi |  8 ++++----
>  arch/arm/boot/dts/at91sam9rl.dtsi  |  8 ++++----
>  5 files changed, 20 insertions(+), 20 deletions(-)
> 
Applied, thanks.

Patch

diff --git a/arch/arm/boot/dts/at91sam9260.dtsi b/arch/arm/boot/dts/at91sam9260.dtsi
index dee9c0c8a096..16c6fd3c4246 100644
--- a/arch/arm/boot/dts/at91sam9260.dtsi
+++ b/arch/arm/boot/dts/at91sam9260.dtsi
@@ -187,7 +187,7 @@ 
 				usart0 {
 					pinctrl_usart0: usart0-0 {
 						atmel,pins =
-							<AT91_PIOB 4 AT91_PERIPH_A AT91_PINCTRL_NONE
+							<AT91_PIOB 4 AT91_PERIPH_A AT91_PINCTRL_PULL_UP
 							 AT91_PIOB 5 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -221,7 +221,7 @@ 
 				usart1 {
 					pinctrl_usart1: usart1-0 {
 						atmel,pins =
-							<AT91_PIOB 6 AT91_PERIPH_A AT91_PINCTRL_NONE
+							<AT91_PIOB 6 AT91_PERIPH_A AT91_PINCTRL_PULL_UP
 							 AT91_PIOB 7 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -239,7 +239,7 @@ 
 				usart2 {
 					pinctrl_usart2: usart2-0 {
 						atmel,pins =
-							<AT91_PIOB 8 AT91_PERIPH_A AT91_PINCTRL_NONE
+							<AT91_PIOB 8 AT91_PERIPH_A AT91_PINCTRL_PULL_UP
 							 AT91_PIOB 9 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -257,7 +257,7 @@ 
 				usart3 {
 					pinctrl_usart3: usart3-0 {
 						atmel,pins =
-							<AT91_PIOB 10 AT91_PERIPH_A AT91_PINCTRL_NONE
+							<AT91_PIOB 10 AT91_PERIPH_A AT91_PINCTRL_PULL_UP
 							 AT91_PIOB 11 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -275,7 +275,7 @@ 
 				uart0 {
 					pinctrl_uart0: uart0-0 {
 						atmel,pins =
-							<AT91_PIOA 31 AT91_PERIPH_B AT91_PINCTRL_NONE
+							<AT91_PIOA 31 AT91_PERIPH_B AT91_PINCTRL_PULL_UP
 							 AT91_PIOA 30 AT91_PERIPH_B AT91_PINCTRL_PULL_UP>;
 					};
 				};
@@ -283,7 +283,7 @@ 
 				uart1 {
 					pinctrl_uart1: uart1-0 {
 						atmel,pins =
-							<AT91_PIOB 12 AT91_PERIPH_A AT91_PINCTRL_NONE
+							<AT91_PIOB 12 AT91_PERIPH_A AT91_PINCTRL_PULL_UP
 							 AT91_PIOB 13 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};
 				};
diff --git a/arch/arm/boot/dts/at91sam9261.dtsi b/arch/arm/boot/dts/at91sam9261.dtsi
index dba025a98527..5ed3d745ac86 100644
--- a/arch/arm/boot/dts/at91sam9261.dtsi
+++ b/arch/arm/boot/dts/at91sam9261.dtsi
@@ -329,7 +329,7 @@ 
 				usart0 {
 					pinctrl_usart0: usart0-0 {
 						atmel,pins =
-							<AT91_PIOC 8 AT91_PERIPH_A AT91_PINCTRL_NONE>,
+							<AT91_PIOC 8 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>,
 							<AT91_PIOC 9 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -347,7 +347,7 @@ 
 				usart1 {
 					pinctrl_usart1: usart1-0 {
 						atmel,pins =
-							<AT91_PIOC 12 AT91_PERIPH_A AT91_PINCTRL_NONE>,
+							<AT91_PIOC 12 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>,
 							<AT91_PIOC 13 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -365,7 +365,7 @@ 
 				usart2 {
 					pinctrl_usart2: usart2-0 {
 						atmel,pins =
-							<AT91_PIOC 14 AT91_PERIPH_A AT91_PINCTRL_NONE>,
+							<AT91_PIOC 14 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>,
 							<AT91_PIOC 15 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

diff --git a/arch/arm/boot/dts/at91sam9263.dtsi b/arch/arm/boot/dts/at91sam9263.dtsi
index 99678abdda93..5c990cfae254 100644
--- a/arch/arm/boot/dts/at91sam9263.dtsi
+++ b/arch/arm/boot/dts/at91sam9263.dtsi
@@ -183,7 +183,7 @@ 
 				usart0 {
 					pinctrl_usart0: usart0-0 {
 						atmel,pins =
-							<AT91_PIOA 26 AT91_PERIPH_A AT91_PINCTRL_NONE
+							<AT91_PIOA 26 AT91_PERIPH_A AT91_PINCTRL_PULL_UP
 							 AT91_PIOA 27 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -201,7 +201,7 @@ 
 				usart1 {
 					pinctrl_usart1: usart1-0 {
 						atmel,pins =
-							<AT91_PIOD 0 AT91_PERIPH_A AT91_PINCTRL_NONE
+							<AT91_PIOD 0 AT91_PERIPH_A AT91_PINCTRL_PULL_UP
 							 AT91_PIOD 1 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -219,7 +219,7 @@ 
 				usart2 {
 					pinctrl_usart2: usart2-0 {
 						atmel,pins =
-							<AT91_PIOD 2 AT91_PERIPH_A AT91_PINCTRL_NONE
+							<AT91_PIOD 2 AT91_PERIPH_A AT91_PINCTRL_PULL_UP
 							 AT91_PIOD 3 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

diff --git a/arch/arm/boot/dts/at91sam9g45.dtsi b/arch/arm/boot/dts/at91sam9g45.dtsi
index 691c95ea6175..fd179097a4bf 100644
--- a/arch/arm/boot/dts/at91sam9g45.dtsi
+++ b/arch/arm/boot/dts/at91sam9g45.dtsi
@@ -556,7 +556,7 @@ 
 				usart0 {
 					pinctrl_usart0: usart0-0 {
 						atmel,pins =
-							<AT91_PIOB 19 AT91_PERIPH_A AT91_PINCTRL_NONE
+							<AT91_PIOB 19 AT91_PERIPH_A AT91_PINCTRL_PULL_UP
 							 AT91_PIOB 18 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -574,7 +574,7 @@ 
 				usart1 {
 					pinctrl_usart1: usart1-0 {
 						atmel,pins =
-							<AT91_PIOB 4 AT91_PERIPH_A AT91_PINCTRL_NONE
+							<AT91_PIOB 4 AT91_PERIPH_A AT91_PINCTRL_PULL_UP
 							 AT91_PIOB 5 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -592,7 +592,7 @@ 
 				usart2 {
 					pinctrl_usart2: usart2-0 {
 						atmel,pins =
-							<AT91_PIOB 6 AT91_PERIPH_A AT91_PINCTRL_NONE
+							<AT91_PIOB 6 AT91_PERIPH_A AT91_PINCTRL_PULL_UP
 							 AT91_PIOB 7 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -610,7 +610,7 @@ 
 				usart3 {
 					pinctrl_usart3: usart3-0 {
 						atmel,pins =
-							<AT91_PIOB 8 AT91_PERIPH_A AT91_PINCTRL_NONE
+							<AT91_PIOB 8 AT91_PERIPH_A AT91_PINCTRL_PULL_UP
 							 AT91_PIOB 9 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

diff --git a/arch/arm/boot/dts/at91sam9rl.dtsi b/arch/arm/boot/dts/at91sam9rl.dtsi
index 8643b7151565..ea024e4b6e09 100644
--- a/arch/arm/boot/dts/at91sam9rl.dtsi
+++ b/arch/arm/boot/dts/at91sam9rl.dtsi
@@ -682,7 +682,7 @@ 
 				usart0 {
 					pinctrl_usart0: usart0-0 {
 						atmel,pins =
-							<AT91_PIOA 6 AT91_PERIPH_A AT91_PINCTRL_NONE>,
+							<AT91_PIOA 6 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>,
 							<AT91_PIOA 7 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -721,7 +721,7 @@ 
 				usart1 {
 					pinctrl_usart1: usart1-0 {
 						atmel,pins =
-							<AT91_PIOA 11 AT91_PERIPH_A AT91_PINCTRL_NONE>,
+							<AT91_PIOA 11 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>,
 							<AT91_PIOA 12 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -744,7 +744,7 @@ 
 				usart2 {
 					pinctrl_usart2: usart2-0 {
 						atmel,pins =
-							<AT91_PIOA 13 AT91_PERIPH_A AT91_PINCTRL_NONE>,
+							<AT91_PIOA 13 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>,
 							<AT91_PIOA 14 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};

@@ -767,7 +767,7 @@ 
 				usart3 {
 					pinctrl_usart3: usart3-0 {
 						atmel,pins =
-							<AT91_PIOB 0 AT91_PERIPH_A AT91_PINCTRL_NONE>,
+							<AT91_PIOB 0 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>,
 							<AT91_PIOB 1 AT91_PERIPH_A AT91_PINCTRL_PULL_UP>;
 					};