[PATCH v11 0/8] Turris Omnia MCU driver

[PATCH v11 0/8] Turris Omnia MCU driver

[Marek Behún]

Hello Andy, Hans, Ilpo, Arnd, Gregory, and others,

this is v11 of the series adding Turris Omnia MCU driver.

Changes since v10:
- dropped patch 7 from v10 ("Add support for digital message signing via
  debugfs"). This must be done via different kernel API (should be
  doable via keyctl), but this requires more work which I currently
  don't have, unfortunately
- in patch 3 where I introduce support for MCU connected GPIOs
  changed u32 types to unsigned long where it made sense, in order
  to be able to use __assign_bit(), __set_bit(), test_bit().
  This was suggested by Andy.
- in patch 3 deduplicated code in omnia_gpio_get_multiple()
- moved the "fixing" in patch 3 of functions introduced in patch 2
  to patch 2, this was a rebasing error in v10
- changed date to September 2024 and KernelVersion to 6.11 in
  Documentation/ABI/testing/sysfs-bus-i2c-devices-turris-omnia-mcu

Links to previous cover letters (v1 to v10):
  https://patchwork.kernel.org/project/linux-soc/cover/20230823161012.6986-1-kabel@kernel.org/
  https://patchwork.kernel.org/project/linux-soc/cover/20230919103815.16818-1-kabel@kernel.org/
  https://patchwork.kernel.org/project/linux-soc/cover/20231023143130.11602-1-kabel@kernel.org/
  https://patchwork.kernel.org/project/linux-soc/cover/20231026161803.16750-1-kabel@kernel.org/
  https://patchwork.kernel.org/project/linux-soc/cover/20240323164359.21642-1-kabel@kernel.org/
  https://patchwork.kernel.org/project/linux-soc/cover/20240418121116.22184-1-kabel@kernel.org/
  https://patchwork.kernel.org/project/linux-soc/cover/20240424173809.7214-1-kabel@kernel.org/
  https://patchwork.kernel.org/project/linux-soc/cover/20240430115111.3453-1-kabel@kernel.org/
  https://patchwork.kernel.org/project/linux-soc/cover/20240508103118.23345-1-kabel@kernel.org/
  https://patchwork.kernel.org/project/linux-soc/cover/20240510101819.13551-1-kabel@kernel.org/

Marek Behún (8):
  dt-bindings: firmware: add cznic,turris-omnia-mcu binding
  platform: cznic: Add preliminary support for Turris Omnia MCU
  platform: cznic: turris-omnia-mcu: Add support for MCU connected GPIOs
  platform: cznic: turris-omnia-mcu: Add support for poweroff and wakeup
  platform: cznic: turris-omnia-mcu: Add support for MCU watchdog
  platform: cznic: turris-omnia-mcu: Add support for MCU provided TRNG
  ARM: dts: turris-omnia: Add MCU system-controller node
  ARM: dts: turris-omnia: Add GPIO key node for front button

 .../sysfs-bus-i2c-devices-turris-omnia-mcu    |  113 ++
 .../firmware/cznic,turris-omnia-mcu.yaml      |   86 ++
 MAINTAINERS                                   |    4 +
 .../dts/marvell/armada-385-turris-omnia.dts   |   35 +-
 drivers/platform/Kconfig                      |    2 +
 drivers/platform/Makefile                     |    1 +
 drivers/platform/cznic/Kconfig                |   48 +
 drivers/platform/cznic/Makefile               |    8 +
 .../platform/cznic/turris-omnia-mcu-base.c    |  407 +++++++
 .../platform/cznic/turris-omnia-mcu-gpio.c    | 1071 +++++++++++++++++
 .../cznic/turris-omnia-mcu-sys-off-wakeup.c   |  257 ++++
 .../platform/cznic/turris-omnia-mcu-trng.c    |  103 ++
 .../cznic/turris-omnia-mcu-watchdog.c         |  128 ++
 drivers/platform/cznic/turris-omnia-mcu.h     |  194 +++
 include/linux/turris-omnia-mcu-interface.h    |  249 ++++
 15 files changed, 2705 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/ABI/testing/sysfs-bus-i2c-devices-turris-omnia-mcu
 create mode 100644 Documentation/devicetree/bindings/firmware/cznic,turris-omnia-mcu.yaml
 create mode 100644 drivers/platform/cznic/Kconfig
 create mode 100644 drivers/platform/cznic/Makefile
 create mode 100644 drivers/platform/cznic/turris-omnia-mcu-base.c
 create mode 100644 drivers/platform/cznic/turris-omnia-mcu-gpio.c
 create mode 100644 drivers/platform/cznic/turris-omnia-mcu-sys-off-wakeup.c
 create mode 100644 drivers/platform/cznic/turris-omnia-mcu-trng.c
 create mode 100644 drivers/platform/cznic/turris-omnia-mcu-watchdog.c
 create mode 100644 drivers/platform/cznic/turris-omnia-mcu.h
 create mode 100644 include/linux/turris-omnia-mcu-interface.h

-- 
2.44.2

[PATCH v11 1/8] dt-bindings: firmware: add cznic,turris-omnia-mcu binding

[Marek Behún]

Add binding for cznic,turris-omnia-mcu, the device-tree node
representing the system-controller features provided by the MCU on the
Turris Omnia router.

Signed-off-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
---
 .../firmware/cznic,turris-omnia-mcu.yaml      | 86 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 87 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/firmware/cznic,turris-omnia-mcu.yaml

diff --git a/Documentation/devicetree/bindings/firmware/cznic,turris-omnia-mcu.yaml b/Documentation/devicetree/bindings/firmware/cznic,turris-omnia-mcu.yaml
new file mode 100644
index 000000000000..af9249695ef5
--- /dev/null
+++ b/Documentation/devicetree/bindings/firmware/cznic,turris-omnia-mcu.yaml
@@ -0,0 +1,86 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/firmware/cznic,turris-omnia-mcu.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: CZ.NIC's Turris Omnia MCU
+
+maintainers:
+  - Marek Behún <kabel@kernel.org>
+
+description:
+  The MCU on Turris Omnia acts as a system controller providing additional
+  GPIOs, interrupts, watchdog, system power off and wakeup configuration.
+
+properties:
+  compatible:
+    const: cznic,turris-omnia-mcu
+
+  reg:
+    description: MCU I2C slave address
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  interrupt-controller: true
+
+  '#interrupt-cells':
+    const: 2
+    description: |
+      The first cell specifies the interrupt number (0 to 63), the second cell
+      specifies interrupt type (which can be one of IRQ_TYPE_EDGE_RISING,
+      IRQ_TYPE_EDGE_FALLING or IRQ_TYPE_EDGE_BOTH).
+      The interrupt numbers correspond sequentially to GPIO numbers, taking the
+      GPIO banks into account:
+        IRQ number   GPIO bank   GPIO pin within bank
+           0 - 15      0           0 - 15
+          16 - 47      1           0 - 31
+          48 - 63      2           0 - 15
+      There are several exceptions:
+        IRQ number   meaning
+          11           LED panel brightness changed by button press
+          13           TRNG entropy ready
+          14           ECDSA message signature computation done
+
+  gpio-controller: true
+
+  '#gpio-cells':
+    const: 3
+    description:
+      The first cell is bank number (0, 1 or 2), the second cell is pin number
+      within the bank (0 to 15 for banks 0 and 2, 0 to 31 for bank 1), and the
+      third cell specifies consumer flags.
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - interrupt-controller
+  - gpio-controller
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        system-controller@2a {
+            compatible = "cznic,turris-omnia-mcu";
+            reg = <0x2a>;
+
+            interrupt-parent = <&gpio1>;
+            interrupts = <11 IRQ_TYPE_NONE>;
+
+            gpio-controller;
+            #gpio-cells = <3>;
+
+            interrupt-controller;
+            #interrupt-cells = <2>;
+        };
+    };
diff --git a/MAINTAINERS b/MAINTAINERS
index 8754ac2c259d..ee8b6dcd8f53 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2211,6 +2211,7 @@ F:	Documentation/ABI/testing/sysfs-bus-moxtet-devices
 F:	Documentation/ABI/testing/sysfs-firmware-turris-mox-rwtm
 F:	Documentation/devicetree/bindings/bus/moxtet.txt
 F:	Documentation/devicetree/bindings/firmware/cznic,turris-mox-rwtm.txt
+F:	Documentation/devicetree/bindings/firmware/cznic,turris-omnia-mcu.yaml
 F:	Documentation/devicetree/bindings/gpio/gpio-moxtet.txt
 F:	Documentation/devicetree/bindings/leds/cznic,turris-omnia-leds.yaml
 F:	Documentation/devicetree/bindings/watchdog/armada-37xx-wdt.txt
-- 
2.44.2

[PATCH v11 7/8] ARM: dts: turris-omnia: Add MCU system-controller node

[Marek Behún]

Turris Omnia's MCU provides various features that can be configured over
I2C at address 0x2a. Add device-tree node.

This does not carry a Fixes tag - we do not want this to get backported
to stable kernels for the following reason: U-Boot since v2022.10
inserts a phy-reset-gpio property into the WAN ethernet node pointing to
the MCU node if it finds the MCU node with a cznic,turris-omnia-mcu
compatible. Thus if this change got backported to a stable kernel, the
WAN interface driver would defer probe indefinitely (since it would wait
for the turris-omnia-mcu driver which would not be present).

Signed-off-by: Marek Behún <kabel@kernel.org>
---
 .../dts/marvell/armada-385-turris-omnia.dts   | 22 ++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/marvell/armada-385-turris-omnia.dts b/arch/arm/boot/dts/marvell/armada-385-turris-omnia.dts
index 7b755bb4e4e7..59079d63fe27 100644
--- a/arch/arm/boot/dts/marvell/armada-385-turris-omnia.dts
+++ b/arch/arm/boot/dts/marvell/armada-385-turris-omnia.dts
@@ -218,7 +218,22 @@ i2c@0 {
 			#size-cells = <0>;
 			reg = <0>;
 
-			/* STM32F0 command interface at address 0x2a */
+			mcu: system-controller@2a {
+				compatible = "cznic,turris-omnia-mcu";
+				reg = <0x2a>;
+
+				pinctrl-names = "default";
+				pinctrl-0 = <&mcu_pins>;
+
+				interrupt-parent = <&gpio1>;
+				interrupts = <11 IRQ_TYPE_NONE>;
+
+				gpio-controller;
+				#gpio-cells = <3>;
+
+				interrupt-controller;
+				#interrupt-cells = <2>;
+			};
 
 			led-controller@2b {
 				compatible = "cznic,turris-omnia-leds";
@@ -501,6 +516,11 @@ fixed-link {
 };
 
 &pinctrl {
+	mcu_pins: mcu-pins {
+		marvell,pins = "mpp43";
+		marvell,function = "gpio";
+	};
+
 	pcawan_pins: pcawan-pins {
 		marvell,pins = "mpp46";
 		marvell,function = "gpio";
-- 
2.44.2

[PATCH v11 8/8] ARM: dts: turris-omnia: Add GPIO key node for front button

[Marek Behún]

Now that we have the MCU device-tree node, which acts as a GPIO
controller, add GPIO key node for the front button.

Signed-off-by: Marek Behún <kabel@kernel.org>
---
 .../boot/dts/marvell/armada-385-turris-omnia.dts    | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/arm/boot/dts/marvell/armada-385-turris-omnia.dts b/arch/arm/boot/dts/marvell/armada-385-turris-omnia.dts
index 59079d63fe27..43202890c959 100644
--- a/arch/arm/boot/dts/marvell/armada-385-turris-omnia.dts
+++ b/arch/arm/boot/dts/marvell/armada-385-turris-omnia.dts
@@ -112,6 +112,19 @@ sfp: sfp {
 		status = "disabled";
 	};
 
+	gpio-keys {
+		compatible = "gpio-keys";
+
+		front-button {
+			label = "Front Button";
+			linux,code = <KEY_VENDOR>;
+			linux,can-disable;
+			gpios = <&mcu 0 12 GPIO_ACTIVE_HIGH>;
+			/* debouncing is done by the microcontroller */
+			debounce-interval = <0>;
+		};
+	};
+
 	sound {
 		compatible = "simple-audio-card";
 		simple-audio-card,name = "SPDIF";
-- 
2.44.2

Re: [PATCH v11 0/8] Turris Omnia MCU driver

[Andy Shevchenko]

On Wed, Jun 5, 2024 at 7:19 PM Marek Behún <kabel@kernel.org> wrote:
>
> Hello Andy, Hans, Ilpo, Arnd, Gregory, and others,
>
> this is v11 of the series adding Turris Omnia MCU driver.

Thank you!
There are a few small issues here and there, but overall LGTM. The
only one main question is what to do with gpiochip_get_desc(). I Cc'ed
Bart for this.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v11 0/8] Turris Omnia MCU driver

[Marek Behún]

On Wed, 5 Jun 2024 22:05:37 +0300
Andy Shevchenko <andy.shevchenko@gmail.com> wrote:

> On Wed, Jun 5, 2024 at 7:19 PM Marek Behún <kabel@kernel.org> wrote:
> >
> > Hello Andy, Hans, Ilpo, Arnd, Gregory, and others,
> >
> > this is v11 of the series adding Turris Omnia MCU driver.  
> 
> Thank you!
> There are a few small issues here and there, but overall LGTM. The
> only one main question is what to do with gpiochip_get_desc(). I Cc'ed
> Bart for this.

Thank you for the review, I am going to apply the changes you requested
and wait for Bart, and we'll see what to do with the
gpiochip_get_desc().

Marek