Re: [PATCH 1/5] ARM: dts: stm32: add usart2, usart3 and uart7 pins in stm32mp15-pinctrl

[Alexandre Torgue <alexandre.torgue@st.com>]

Hi Erwan

On 5/28/20 9:40 AM, Erwan Le Ray wrote:
> Adds usart2_pins_c, usart3_pins_b, usart3_pins_c and uart7_pins_c pins
> configurations in stm32mp15-pinctrl.
> - usart2_pins_c pins are connected to Bluetooth chip on dk2 board.
> - usart3_pins_b pins are connected to GPIO expansion connector on evx board.
> - usart3_pins_c pins are connected to GPIO expansion connector on dkx board.
> - uart7_pins_c pins are connected to Arduino Uno connector on dkx board.
> 
> Signed-off-by: Erwan Le Ray <erwan.leray@st.com>
> 
> diff --git a/arch/arm/boot/dts/stm32mp15-pinctrl.dtsi b/arch/arm/boot/dts/stm32mp15-pinctrl.dtsi
> index fb98a66977fe..99e399e4e4c3 100644
> --- a/arch/arm/boot/dts/stm32mp15-pinctrl.dtsi
> +++ b/arch/arm/boot/dts/stm32mp15-pinctrl.dtsi
> @@ -1658,6 +1658,36 @@
>   		};
> 

...


> +	usart3_pins_b: usart3-0 {
> +		pins1 {
> +			pinmux = <STM32_PINMUX('B', 10, AF7)>, /* USART3_TX */
> +				 <STM32_PINMUX('G', 8, AF8)>; /* USART3_RTS */

On EVx board this line is shared with ETH_CLK. The choice between both 
is done thanks to SB23 and default choice is "ETH_CLK". So hardware 
update has to be done to use usart3_rts. some words around that in 
comment would be great.

Thanks
alex

> +			bias-disable;
> +			drive-push-pull;
> +			slew-rate = <0>;
> +		};
> +		pins2 {
> +			pinmux = <STM32_PINMUX('B', 12, AF8)>, /* USART3_RX */
> +				 <STM32_PINMUX('I', 10, AF8)>; /* USART3_CTS_NSS */
> +			bias-disable;
> +		};
> +	};
> +
> +	usart3_idle_pins_b: usart3-idle-0 {
> +		pins1 {
> +			pinmux = <STM32_PINMUX('B', 10, ANALOG)>, /* USART3_TX */
> +				 <STM32_PINMUX('G', 8, ANALOG)>, /* USART3_RTS */
> +				 <STM32_PINMUX('I', 10, ANALOG)>; /* USART3_CTS_NSS */
> +		};
> +		pins2 {
> +			pinmux = <STM32_PINMUX('B', 12, AF8)>; /* USART3_RX */
> +			bias-disable;
> +		};
> +	};
> +
> +	usart3_sleep_pins_b: usart3-sleep-0 {
> +		pins {
> +			pinmux = <STM32_PINMUX('B', 10, ANALOG)>, /* USART3_TX */
> +				 <STM32_PINMUX('G', 8, ANALOG)>, /* USART3_RTS */
> +				 <STM32_PINMUX('I', 10, ANALOG)>, /* USART3_CTS_NSS */
> +				 <STM32_PINMUX('B', 12, ANALOG)>; /* USART3_RX */
> +		};
> +	};
> +
> +	usart3_pins_c: usart3-1 {
> +		pins1 {
> +			pinmux = <STM32_PINMUX('B', 10, AF7)>, /* USART3_TX */
> +				 <STM32_PINMUX('G', 8, AF8)>; /* USART3_RTS */
> +			bias-disable;
> +			drive-push-pull;
> +			slew-rate = <0>;
> +		};
> +		pins2 {
> +			pinmux = <STM32_PINMUX('B', 12, AF8)>, /* USART3_RX */
> +				 <STM32_PINMUX('B', 13, AF7)>; /* USART3_CTS_NSS */
> +			bias-disable;
> +		};
> +	};
> +
> +	usart3_idle_pins_c: usart3-idle-1 {
> +		pins1 {
> +			pinmux = <STM32_PINMUX('B', 10, ANALOG)>, /* USART3_TX */
> +				 <STM32_PINMUX('G', 8, ANALOG)>, /* USART3_RTS */
> +				 <STM32_PINMUX('B', 13, ANALOG)>; /* USART3_CTS_NSS */
> +		};
> +		pins2 {
> +			pinmux = <STM32_PINMUX('B', 12, AF8)>; /* USART3_RX */
> +			bias-disable;
> +		};
> +	};
> +
> +	usart3_sleep_pins_c: usart3-sleep-1 {
> +		pins {
> +			pinmux = <STM32_PINMUX('B', 10, ANALOG)>, /* USART3_TX */
> +				 <STM32_PINMUX('G', 8, ANALOG)>, /* USART3_RTS */
> +				 <STM32_PINMUX('B', 13, ANALOG)>, /* USART3_CTS_NSS */
> +				 <STM32_PINMUX('B', 12, ANALOG)>; /* USART3_RX */
> +		};
> +	};
> +
>   	usbotg_hs_pins_a: usbotg-hs-0 {
>   		pins {
>   			pinmux = <STM32_PINMUX('A', 10, ANALOG)>; /* OTG_ID */
>