[RESEND PATCH v2 0/5] STM32 pinctrl: Add mux function RSVD

[RESEND PATCH v2 0/5] STM32 pinctrl: Add mux function RSVD

[Antonio Borneo]

This v2 is a subset of the v1, split-out to simplify the review.

This subset:
- introduces the pinctrl mux function RSVD,
- adds two use cases requiring RSVD,
- minor re-format of the dt-bindings.

Changes v1 -> v2 subset:
- rebased on v6.16-rc1,
- added use cases of the new mux function RSVD,
- added Reviewed-by: on 2/5 (former 04/14 in v1),
- added commit to re-format the dt-bindings,
- Link to v1: https://lore.kernel.org/lkml/20241022155658.1647350-1-antonio.borneo@foss.st.com/


Antonio Borneo (3):
  ARM: dts: stm32: Add pinmux for CM4 leds pins
  ARM: dts: stm32: Add leds for CM4 on stm32mp15xx-ed1 and
    stm32mp15xx-dkx
  dt-bindings: pinctrl: stm32: Add missing blank lines

Fabien Dessenne (2):
  pinctrl: stm32: Handle RSVD pin configuration
  dt-bindings: pinctrl: stm32: Add RSVD mux function

 .../bindings/pinctrl/st,stm32-pinctrl.yaml    | 25 +++++++++++++++++++
 arch/arm/boot/dts/st/stm32mp15-pinctrl.dtsi   | 14 +++++++++++
 arch/arm/boot/dts/st/stm32mp157c-ed1.dts      |  2 ++
 arch/arm/boot/dts/st/stm32mp15xx-dkx.dtsi     |  2 ++
 drivers/pinctrl/stm32/pinctrl-stm32.c         |  9 +++++++
 drivers/pinctrl/stm32/pinctrl-stm32.h         |  3 ++-
 include/dt-bindings/pinctrl/stm32-pinfunc.h   |  1 +
 7 files changed, 55 insertions(+), 1 deletion(-)


base-commit: 19272b37aa4f83ca52bdf9c16d5d81bdd1354494
-- 
2.34.1

[RESEND PATCH v2 1/5] pinctrl: stm32: Handle RSVD pin configuration

[Antonio Borneo]

From: Fabien Dessenne <fabien.dessenne@foss.st.com>

When a pin is assigned to a coprocessor not running Linux, the pin
should be flagged in the DT as reserved and not usable by Linux.

Add pin configuration RSVD (Reserved) and instrument the driver to
not update the mux setting.

Signed-off-by: Fabien Dessenne <fabien.dessenne@foss.st.com>
Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
---
 drivers/pinctrl/stm32/pinctrl-stm32.c | 9 +++++++++
 drivers/pinctrl/stm32/pinctrl-stm32.h | 3 ++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/pinctrl/stm32/pinctrl-stm32.c b/drivers/pinctrl/stm32/pinctrl-stm32.c
index ba49d48c3a1d1..e0c85f55557af 100644
--- a/drivers/pinctrl/stm32/pinctrl-stm32.c
+++ b/drivers/pinctrl/stm32/pinctrl-stm32.c
@@ -77,6 +77,7 @@ static const char * const stm32_gpio_functions[] = {
 	"af8", "af9", "af10",
 	"af11", "af12", "af13",
 	"af14", "af15", "analog",
+	"reserved",
 };
 
 struct stm32_pinctrl_group {
@@ -541,6 +542,9 @@ static bool stm32_pctrl_is_function_valid(struct stm32_pinctrl *pctl,
 		if (pin->pin.number != pin_num)
 			continue;
 
+		if (fnum == STM32_PIN_RSVD)
+			return true;
+
 		for (k = 0; k < STM32_CONFIG_NUM; k++) {
 			if (func->num == fnum)
 				return true;
@@ -841,6 +845,11 @@ static int stm32_pmx_set_mux(struct pinctrl_dev *pctldev,
 		return -EINVAL;
 	}
 
+	if (function == STM32_PIN_RSVD) {
+		dev_dbg(pctl->dev, "Reserved pins, skipping HW update.\n");
+		return 0;
+	}
+
 	bank = gpiochip_get_data(range->gc);
 	pin = stm32_gpio_pin(g->pin);
 
diff --git a/drivers/pinctrl/stm32/pinctrl-stm32.h b/drivers/pinctrl/stm32/pinctrl-stm32.h
index 5e5de92ddd58c..8a1c9570b078f 100644
--- a/drivers/pinctrl/stm32/pinctrl-stm32.h
+++ b/drivers/pinctrl/stm32/pinctrl-stm32.h
@@ -17,7 +17,8 @@
 #define STM32_PIN_GPIO		0
 #define STM32_PIN_AF(x)		((x) + 1)
 #define STM32_PIN_ANALOG	(STM32_PIN_AF(15) + 1)
-#define STM32_CONFIG_NUM	(STM32_PIN_ANALOG + 1)
+#define STM32_PIN_RSVD		(STM32_PIN_ANALOG + 1)
+#define STM32_CONFIG_NUM	(STM32_PIN_RSVD + 1)
 
 /*  package information */
 #define STM32MP_PKG_AA		BIT(0)
-- 
2.34.1

[RESEND PATCH v2 2/5] dt-bindings: pinctrl: stm32: Add RSVD mux function

[Antonio Borneo]

From: Fabien Dessenne <fabien.dessenne@foss.st.com>

Document the RSVD (Reserved) mux function, used to reserve pins
for a coprocessor not running Linux.

Signed-off-by: Fabien Dessenne <fabien.dessenne@foss.st.com>
Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
 .../devicetree/bindings/pinctrl/st,stm32-pinctrl.yaml     | 8 ++++++++
 include/dt-bindings/pinctrl/stm32-pinfunc.h               | 1 +
 2 files changed, 9 insertions(+)

diff --git a/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.yaml b/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.yaml
index a28d77748095a..5d17d6487ae9c 100644
--- a/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.yaml
+++ b/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.yaml
@@ -160,9 +160,13 @@ patternProperties:
               * ...
               * 16 : Alternate Function 15
               * 17 : Analog
+              * 18 : Reserved
               To simplify the usage, macro is available to generate "pinmux" field.
               This macro is available here:
                 - include/dt-bindings/pinctrl/stm32-pinfunc.h
+              Setting the pinmux's function to the Reserved (RSVD) value is used to inform
+              the driver that it shall not apply the mux setting. This can be used to
+              reserve some pins, for example to a co-processor not running Linux.
               Some examples of using macro:
                /* GPIO A9 set as alternate function 2 */
                ... {
@@ -176,6 +180,10 @@ patternProperties:
                ... {
                           pinmux = <STM32_PINMUX('A', 9, ANALOG)>;
                };
+               /* GPIO A9 reserved for co-processor */
+               ... {
+                          pinmux = <STM32_PINMUX('A', 9, RSVD)>;
+               };
 
           bias-disable:
             type: boolean
diff --git a/include/dt-bindings/pinctrl/stm32-pinfunc.h b/include/dt-bindings/pinctrl/stm32-pinfunc.h
index 28ad0235086a6..af3fd388329a0 100644
--- a/include/dt-bindings/pinctrl/stm32-pinfunc.h
+++ b/include/dt-bindings/pinctrl/stm32-pinfunc.h
@@ -26,6 +26,7 @@
 #define AF14	0xf
 #define AF15	0x10
 #define ANALOG	0x11
+#define RSVD	0x12
 
 /* define Pins number*/
 #define PIN_NO(port, line)	(((port) - 'A') * 0x10 + (line))
-- 
2.34.1

[RESEND PATCH v2 3/5] ARM: dts: stm32: Add pinmux for CM4 leds pins

[Antonio Borneo]

The GPIO H7 on boards stm32mp15xx-dkx and the GPIO D8 on boards
stm32mp15xx-ed1 are used by the coprocessor Cortex-M4.
Linux running on Cortex-A should not use the GPIO and should left
it available for the coprocessor.

Add two pinmux groups, one for each families of boards, setting
the GPIO function as Reserved (RSVD).

Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
---
 arch/arm/boot/dts/st/stm32mp15-pinctrl.dtsi | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/arch/arm/boot/dts/st/stm32mp15-pinctrl.dtsi b/arch/arm/boot/dts/st/stm32mp15-pinctrl.dtsi
index 40605ea85ee1d..835b034d0aa7e 100644
--- a/arch/arm/boot/dts/st/stm32mp15-pinctrl.dtsi
+++ b/arch/arm/boot/dts/st/stm32mp15-pinctrl.dtsi
@@ -1304,6 +1304,20 @@ pins {
 		};
 	};
 
+	/omit-if-no-ref/
+	m4_leds_orange_pins_a: m4-leds-orange-0 {
+		pins {
+			pinmux = <STM32_PINMUX('H', 7, RSVD)>;
+		};
+	};
+
+	/omit-if-no-ref/
+	m4_leds_orange_pins_b: m4-leds-orange-1 {
+		pins {
+			pinmux = <STM32_PINMUX('D', 8, RSVD)>;
+		};
+	};
+
 	/omit-if-no-ref/
 	mco1_pins_a: mco1-0 {
 		pins {
-- 
2.34.1

[RESEND PATCH v2 4/5] ARM: dts: stm32: Add leds for CM4 on stm32mp15xx-ed1 and stm32mp15xx-dkx

[Antonio Borneo]

Add to the node m4_rproc the pinctrl property corresponding to the
orange LED.
The GPIO is reserved for the coprocessor Cortex-M4 and will be
ignored by Linux.

Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
---
 arch/arm/boot/dts/st/stm32mp157c-ed1.dts  | 2 ++
 arch/arm/boot/dts/st/stm32mp15xx-dkx.dtsi | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/arch/arm/boot/dts/st/stm32mp157c-ed1.dts b/arch/arm/boot/dts/st/stm32mp157c-ed1.dts
index 9cf5ed111b52e..f6c478dbd0418 100644
--- a/arch/arm/boot/dts/st/stm32mp157c-ed1.dts
+++ b/arch/arm/boot/dts/st/stm32mp157c-ed1.dts
@@ -328,6 +328,8 @@ &m4_rproc {
 			<&vdev0vring1>, <&vdev0buffer>;
 	mboxes = <&ipcc 0>, <&ipcc 1>, <&ipcc 2>, <&ipcc 3>;
 	mbox-names = "vq0", "vq1", "shutdown", "detach";
+	pinctrl-names = "default";
+	pinctrl-0 = <&m4_leds_orange_pins_b>;
 	interrupt-parent = <&exti>;
 	interrupts = <68 1>;
 	status = "okay";
diff --git a/arch/arm/boot/dts/st/stm32mp15xx-dkx.dtsi b/arch/arm/boot/dts/st/stm32mp15xx-dkx.dtsi
index a5511b1f0ce30..26f36a232d42d 100644
--- a/arch/arm/boot/dts/st/stm32mp15xx-dkx.dtsi
+++ b/arch/arm/boot/dts/st/stm32mp15xx-dkx.dtsi
@@ -479,6 +479,8 @@ &m4_rproc {
 			<&vdev0vring1>, <&vdev0buffer>;
 	mboxes = <&ipcc 0>, <&ipcc 1>, <&ipcc 2>, <&ipcc 3>;
 	mbox-names = "vq0", "vq1", "shutdown", "detach";
+	pinctrl-names = "default";
+	pinctrl-0 = <&m4_leds_orange_pins_a>;
 	interrupt-parent = <&exti>;
 	interrupts = <68 1>;
 	status = "okay";
-- 
2.34.1

[RESEND PATCH v2 5/5] dt-bindings: pinctrl: stm32: Add missing blank lines

[Antonio Borneo]

Separate the properties through a blank line.

Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
---
 .../bindings/pinctrl/st,stm32-pinctrl.yaml      | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.yaml b/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.yaml
index 5d17d6487ae9c..961161c2ab62b 100644
--- a/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.yaml
+++ b/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.yaml
@@ -32,13 +32,16 @@ properties:
 
   '#address-cells':
     const: 1
+
   '#size-cells':
     const: 1
 
   ranges: true
+
   pins-are-numbered:
     $ref: /schemas/types.yaml#/definitions/flag
     deprecated: true
+
   hwlocks: true
 
   interrupts:
@@ -67,22 +70,29 @@ patternProperties:
     additionalProperties: false
     properties:
       gpio-controller: true
+
       '#gpio-cells':
         const: 2
+
       interrupt-controller: true
       '#interrupt-cells':
         const: 2
 
       reg:
         maxItems: 1
+
       clocks:
         maxItems: 1
+
       resets:
         maxItems: 1
+
       gpio-line-names: true
+
       gpio-ranges:
         minItems: 1
         maxItems: 16
+
       ngpios:
         description:
           Number of available gpios in a bank.
@@ -187,18 +197,25 @@ patternProperties:
 
           bias-disable:
             type: boolean
+
           bias-pull-down:
             type: boolean
+
           bias-pull-up:
             type: boolean
+
           drive-push-pull:
             type: boolean
+
           drive-open-drain:
             type: boolean
+
           output-low:
             type: boolean
+
           output-high:
             type: boolean
+
           slew-rate:
             description: |
               0: Low speed
-- 
2.34.1

Re: [RESEND PATCH v2 5/5] dt-bindings: pinctrl: stm32: Add missing blank lines

[Rob Herring (Arm)]

On Tue, 10 Jun 2025 17:23:09 +0200, Antonio Borneo wrote:
> Separate the properties through a blank line.
> 
> Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
> ---
>  .../bindings/pinctrl/st,stm32-pinctrl.yaml      | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
> 

Acked-by: Rob Herring (Arm) <robh@kernel.org>

Re: [RESEND PATCH v2 5/5] dt-bindings: pinctrl: stm32: Add missing blank lines

[Linus Walleij]

On Tue, Jun 10, 2025 at 5:24 PM Antonio Borneo
<antonio.borneo@foss.st.com> wrote:

> Separate the properties through a blank line.
>
> Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>

This patch 5/5 applied to the pinctrl tree.

Yours,
Linus Walleij

Re: [RESEND PATCH v2 0/5] STM32 pinctrl: Add mux function RSVD

[Linus Walleij]

On Tue, Jun 10, 2025 at 5:24 PM Antonio Borneo
<antonio.borneo@foss.st.com> wrote:

> Antonio Borneo (3):
>   ARM: dts: stm32: Add pinmux for CM4 leds pins
>   ARM: dts: stm32: Add leds for CM4 on stm32mp15xx-ed1 and
>     stm32mp15xx-dkx

Please apply these two through the SoC tree.

>   dt-bindings: pinctrl: stm32: Add missing blank lines

Waiting for a DT binding maintainer review on this one.

> Fabien Dessenne (2):
>   pinctrl: stm32: Handle RSVD pin configuration
>   dt-bindings: pinctrl: stm32: Add RSVD mux function

I applied these tow because I have a DT binding ACK on 2/5.

Yours,
Linus Walleij

Re: [RESEND PATCH v2 0/5] STM32 pinctrl: Add mux function RSVD

[Alexandre TORGUE]

Ciao Antonio

On 6/10/25 17:23, Antonio Borneo wrote:
> This v2 is a subset of the v1, split-out to simplify the review.
> 
> This subset:
> - introduces the pinctrl mux function RSVD,
> - adds two use cases requiring RSVD,
> - minor re-format of the dt-bindings.
> 
> Changes v1 -> v2 subset:
> - rebased on v6.16-rc1,
> - added use cases of the new mux function RSVD,
> - added Reviewed-by: on 2/5 (former 04/14 in v1),
> - added commit to re-format the dt-bindings,
> - Link to v1: https://lore.kernel.org/lkml/20241022155658.1647350-1-antonio.borneo@foss.st.com/
> 
> 
> Antonio Borneo (3):
>    ARM: dts: stm32: Add pinmux for CM4 leds pins
>    ARM: dts: stm32: Add leds for CM4 on stm32mp15xx-ed1 and
>      stm32mp15xx-dkx
>    dt-bindings: pinctrl: stm32: Add missing blank lines
> 
> Fabien Dessenne (2):
>    pinctrl: stm32: Handle RSVD pin configuration
>    dt-bindings: pinctrl: stm32: Add RSVD mux function
> 
>   .../bindings/pinctrl/st,stm32-pinctrl.yaml    | 25 +++++++++++++++++++
>   arch/arm/boot/dts/st/stm32mp15-pinctrl.dtsi   | 14 +++++++++++
>   arch/arm/boot/dts/st/stm32mp157c-ed1.dts      |  2 ++
>   arch/arm/boot/dts/st/stm32mp15xx-dkx.dtsi     |  2 ++
>   drivers/pinctrl/stm32/pinctrl-stm32.c         |  9 +++++++
>   drivers/pinctrl/stm32/pinctrl-stm32.h         |  3 ++-
>   include/dt-bindings/pinctrl/stm32-pinfunc.h   |  1 +
>   7 files changed, 55 insertions(+), 1 deletion(-)
> 
> 
> base-commit: 19272b37aa4f83ca52bdf9c16d5d81bdd1354494

DT patches applied on stm32-next.

Thanks!!
Alex