The series adds support for the basic extended CAN controller (bxCAN)
found in many low- to middle-end STM32 SoCs.
The driver design (one core module and one driver module) was inspired
by other ST drivers (e. g. drivers/iio/adc/stm32-adc.c,
drivers/iio/adc/stm32-adc-core.c) where device instances share resources.
The shared resources functions are implemented in the core module, the
device driver in a separate module.
The driver has been tested on the stm32f469i-discovery board with a
kernel version 5.19.0-rc2 in loopback + silent mode:
ip link set can0 type can bitrate 125000 loopback on listen-only on
ip link set up can0
candump can0 -L &
cansend can0 300#AC.AB.AD.AE.75.49.AD.D1
For uboot and kernel compilation, as well as for rootfs creation I used
buildroot:
make stm32f469_disco_sd_defconfig
make
but I had to patch can-utils and busybox as can-utils and iproute are
not compiled for MMU-less microcotrollers. In the case of can-utils,
replacing the calls to fork() with vfork(), I was able to compile the
package with working candump and cansend applications, while in the
case of iproute, I ran into more than one problem and finally I decided
to extend busybox's ip link command for CAN-type devices. I'm still
wondering if it was really necessary, but this way I was able to test
the driver.
Changes in v2:
- Change the file name into 'st,stm32-bxcan-core.yaml'.
- Rename compatibles:
- st,stm32-bxcan-core -> st,stm32f4-bxcan-core
- st,stm32-bxcan -> st,stm32f4-bxcan
- Rename master property to st,can-master.
- Remove the status property from the example.
- Put the node child properties as required.
- Remove a blank line.
- Fix sparse errors.
- Create a MAINTAINERS entry.
- Remove the print of the registers address.
- Remove the volatile keyword from bxcan_rmw().
- Use tx ring algorithm to manage tx mailboxes.
- Use can_{get|put}_echo_skb().
- Update DT properties.
Dario Binacchi (4):
dt-bindings: net: can: add STM32 bxcan DT bindings
ARM: dts: stm32: add CAN support on stm32f429
ARM: dts: stm32: add pin map for CAN controller on stm32f4
can: bxcan: add support for ST bxCAN controller
.../bindings/net/can/st,stm32-bxcan.yaml | 136 +++
MAINTAINERS | 7 +
arch/arm/boot/dts/stm32f4-pinctrl.dtsi | 31 +
arch/arm/boot/dts/stm32f429.dtsi | 30 +
drivers/net/can/Kconfig | 1 +
drivers/net/can/Makefile | 1 +
drivers/net/can/bxcan/Kconfig | 34 +
drivers/net/can/bxcan/Makefile | 4 +
drivers/net/can/bxcan/bxcan-core.c | 200 ++++
drivers/net/can/bxcan/bxcan-core.h | 33 +
drivers/net/can/bxcan/bxcan-drv.c | 1043 +++++++++++++++++
11 files changed, 1520 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
create mode 100644 drivers/net/can/bxcan/Kconfig
create mode 100644 drivers/net/can/bxcan/Makefile
create mode 100644 drivers/net/can/bxcan/bxcan-core.c
create mode 100644 drivers/net/can/bxcan/bxcan-core.h
create mode 100644 drivers/net/can/bxcan/bxcan-drv.c
--
2.32.0
Add support for bxcan (Basic eXtended CAN controller) to STM32F429. The
chip contains two CAN peripherals, CAN1 the master and CAN2 the slave,
that share some of the required logic like clock and filters. This means
that the slave CAN can't be used without the master CAN.
Signed-off-by: Dario Binacchi <[email protected]>
Signed-off-by: Dario Binacchi <[email protected]>
---
(no changes since v1)
arch/arm/boot/dts/stm32f429.dtsi | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/arch/arm/boot/dts/stm32f429.dtsi b/arch/arm/boot/dts/stm32f429.dtsi
index c31ceb821231..da46d13e7ad4 100644
--- a/arch/arm/boot/dts/stm32f429.dtsi
+++ b/arch/arm/boot/dts/stm32f429.dtsi
@@ -362,6 +362,36 @@ i2c3: i2c@40005c00 {
status = "disabled";
};
+ can: can@40006400 {
+ compatible = "st,stm32f4-bxcan-core";
+ reg = <0x40006400 0x800>;
+ resets = <&rcc STM32F4_APB1_RESET(CAN1)>;
+ clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN1)>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+
+ can1: can@0 {
+ compatible = "st,stm32f4-bxcan";
+ reg = <0x0>;
+ interrupts = <19>, <20>, <21>, <22>;
+ interrupt-names = "tx", "rx0", "rx1", "sce";
+ resets = <&rcc STM32F4_APB1_RESET(CAN1)>;
+ st,can-master;
+ status = "disabled";
+ };
+
+ can2: can@400 {
+ compatible = "st,stm32f4-bxcan";
+ reg = <0x400>;
+ interrupts = <63>, <64>, <65>, <66>;
+ interrupt-names = "tx", "rx0", "rx1", "sce";
+ resets = <&rcc STM32F4_APB1_RESET(CAN2)>;
+ clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN2)>;
+ status = "disabled";
+ };
+ };
+
dac: dac@40007400 {
compatible = "st,stm32f4-dac-core";
reg = <0x40007400 0x400>;
--
2.32.0
Add documentation of device tree bindings for the STM32 basic extended
CAN (bxcan) controller.
Signed-off-by: Dario Binacchi <[email protected]>
Signed-off-by: Dario Binacchi <[email protected]>
---
Changes in v2:
- Change the file name into 'st,stm32-bxcan-core.yaml'.
- Rename compatibles:
- st,stm32-bxcan-core -> st,stm32f4-bxcan-core
- st,stm32-bxcan -> st,stm32f4-bxcan
- Rename master property to st,can-master.
- Remove the status property from the example.
- Put the node child properties as required.
.../bindings/net/can/st,stm32-bxcan.yaml | 136 ++++++++++++++++++
1 file changed, 136 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
diff --git a/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
new file mode 100644
index 000000000000..288631b5556d
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
@@ -0,0 +1,136 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/can/st,stm32-bxcan.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: STMicroelectronics bxCAN controller
+
+description: STMicroelectronics BxCAN controller for CAN bus
+
+maintainers:
+ - Dario Binacchi <[email protected]>
+
+allOf:
+ - $ref: can-controller.yaml#
+
+properties:
+ compatible:
+ enum:
+ - st,stm32f4-bxcan-core
+
+ reg:
+ maxItems: 1
+
+ resets:
+ maxItems: 1
+
+ clocks:
+ description:
+ Input clock for registers access
+ maxItems: 1
+
+ '#address-cells':
+ const: 1
+
+ '#size-cells':
+ const: 0
+
+additionalProperties: false
+
+required:
+ - compatible
+ - reg
+ - resets
+ - clocks
+ - '#address-cells'
+ - '#size-cells'
+
+patternProperties:
+ "^can@[0-9]+$":
+ type: object
+ description:
+ A CAN block node contains two subnodes, representing each one a CAN
+ instance available on the machine.
+
+ properties:
+ compatible:
+ enum:
+ - st,stm32f4-bxcan
+
+ st,can-master:
+ description:
+ Master and slave mode of the bxCAN peripheral is only relevant
+ if the chip has two CAN peripherals. In that case they share
+ some of the required logic, and that means you cannot use the
+ slave CAN without the master CAN.
+ type: boolean
+
+ reg:
+ description: |
+ Offset of CAN instance in CAN block. Valid values are:
+ - 0x0: CAN1
+ - 0x400: CAN2
+ maxItems: 1
+
+ interrupts:
+ items:
+ - description: transmit interrupt
+ - description: FIFO 0 receive interrupt
+ - description: FIFO 1 receive interrupt
+ - description: status change error interrupt
+
+ interrupt-names:
+ items:
+ - const: tx
+ - const: rx0
+ - const: rx1
+ - const: sce
+
+ resets:
+ maxItems: 1
+
+ clocks:
+ description:
+ Input clock for registers access
+ maxItems: 1
+
+ additionalProperties: false
+
+ required:
+ - compatible
+ - reg
+ - interrupts
+ - resets
+
+examples:
+ - |
+ #include <dt-bindings/clock/stm32fx-clock.h>
+ #include <dt-bindings/mfd/stm32f4-rcc.h>
+
+ can: can@40006400 {
+ compatible = "st,stm32f4-bxcan-core";
+ reg = <0x40006400 0x800>;
+ resets = <&rcc STM32F4_APB1_RESET(CAN1)>;
+ clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN1)>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ can1: can@0 {
+ compatible = "st,stm32f4-bxcan";
+ reg = <0x0>;
+ interrupts = <19>, <20>, <21>, <22>;
+ interrupt-names = "tx", "rx0", "rx1", "sce";
+ resets = <&rcc STM32F4_APB1_RESET(CAN1)>;
+ st,can-master;
+ };
+
+ can2: can@400 {
+ compatible = "st,stm32f4-bxcan";
+ reg = <0x400>;
+ interrupts = <63>, <64>, <65>, <66>;
+ interrupt-names = "tx", "rx0", "rx1", "sce";
+ resets = <&rcc STM32F4_APB1_RESET(CAN2)>;
+ clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN2)>;
+ };
+ };
--
2.32.0
On 20/08/2022 11:29, Dario Binacchi wrote:
> Add documentation of device tree bindings for the STM32 basic extended
> CAN (bxcan) controller.
>
> Signed-off-by: Dario Binacchi <[email protected]>
> Signed-off-by: Dario Binacchi <[email protected]>
>
> ---
>
> Changes in v2:
> - Change the file name into 'st,stm32-bxcan-core.yaml'.
> - Rename compatibles:
> - st,stm32-bxcan-core -> st,stm32f4-bxcan-core
> - st,stm32-bxcan -> st,stm32f4-bxcan
> - Rename master property to st,can-master.
> - Remove the status property from the example.
> - Put the node child properties as required.
>
> .../bindings/net/can/st,stm32-bxcan.yaml | 136 ++++++++++++++++++
> 1 file changed, 136 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
>
> diff --git a/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
> new file mode 100644
> index 000000000000..288631b5556d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
> @@ -0,0 +1,136 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/net/can/st,stm32-bxcan.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: STMicroelectronics bxCAN controller
> +
> +description: STMicroelectronics BxCAN controller for CAN bus
> +
> +maintainers:
> + - Dario Binacchi <[email protected]>
> +
> +allOf:
> + - $ref: can-controller.yaml#
> +
> +properties:
> + compatible:
> + enum:
> + - st,stm32f4-bxcan-core
> +
> + reg:
> + maxItems: 1
> +
> + resets:
> + maxItems: 1
> +
> + clocks:
> + description:
> + Input clock for registers access
> + maxItems: 1
> +
> + '#address-cells':
> + const: 1
> +
> + '#size-cells':
> + const: 0
> +
> +additionalProperties: false
> +
> +required:
> + - compatible
> + - reg
> + - resets
> + - clocks
> + - '#address-cells'
> + - '#size-cells'
> +
> +patternProperties:
No improvements here, so my comment stay. Please fix it.
> + "^can@[0-9]+$":
> + type: object
> + description:
> + A CAN block node contains two subnodes, representing each one a CAN
> + instance available on the machine.
I still do not understand why you need children. You did not CC me on
driver change, so difficult to say. You did not describe the parent
device - there is no description. Why do you need parent device at all?
This looks like some driver-driven-bindings instead of just real
hardware description.
Best regards,
Krzysztof
On Sat, Aug 20, 2022 at 10:29:33AM +0200, Dario Binacchi wrote:
> Add documentation of device tree bindings for the STM32 basic extended
> CAN (bxcan) controller.
>
> Signed-off-by: Dario Binacchi <[email protected]>
> Signed-off-by: Dario Binacchi <[email protected]>
>
> ---
>
> Changes in v2:
> - Change the file name into 'st,stm32-bxcan-core.yaml'.
> - Rename compatibles:
> - st,stm32-bxcan-core -> st,stm32f4-bxcan-core
> - st,stm32-bxcan -> st,stm32f4-bxcan
> - Rename master property to st,can-master.
> - Remove the status property from the example.
> - Put the node child properties as required.
>
> .../bindings/net/can/st,stm32-bxcan.yaml | 136 ++++++++++++++++++
> 1 file changed, 136 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
>
> diff --git a/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
> new file mode 100644
> index 000000000000..288631b5556d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
> @@ -0,0 +1,136 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/net/can/st,stm32-bxcan.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: STMicroelectronics bxCAN controller
> +
> +description: STMicroelectronics BxCAN controller for CAN bus
> +
> +maintainers:
> + - Dario Binacchi <[email protected]>
> +
> +allOf:
> + - $ref: can-controller.yaml#
> +
> +properties:
> + compatible:
> + enum:
> + - st,stm32f4-bxcan-core
> +
> + reg:
> + maxItems: 1
> +
> + resets:
> + maxItems: 1
> +
> + clocks:
> + description:
> + Input clock for registers access
> + maxItems: 1
> +
> + '#address-cells':
> + const: 1
> +
> + '#size-cells':
> + const: 0
> +
> +additionalProperties: false
> +
> +required:
> + - compatible
> + - reg
> + - resets
> + - clocks
> + - '#address-cells'
> + - '#size-cells'
> +
> +patternProperties:
> + "^can@[0-9]+$":
> + type: object
> + description:
> + A CAN block node contains two subnodes, representing each one a CAN
> + instance available on the machine.
> +
> + properties:
> + compatible:
> + enum:
> + - st,stm32f4-bxcan
> +
> + st,can-master:
> + description:
> + Master and slave mode of the bxCAN peripheral is only relevant
> + if the chip has two CAN peripherals. In that case they share
> + some of the required logic, and that means you cannot use the
> + slave CAN without the master CAN.
> + type: boolean
> +
> + reg:
> + description: |
> + Offset of CAN instance in CAN block. Valid values are:
> + - 0x0: CAN1
> + - 0x400: CAN2
> + maxItems: 1
> +
> + interrupts:
> + items:
> + - description: transmit interrupt
> + - description: FIFO 0 receive interrupt
> + - description: FIFO 1 receive interrupt
> + - description: status change error interrupt
> +
> + interrupt-names:
> + items:
> + - const: tx
> + - const: rx0
> + - const: rx1
> + - const: sce
> +
> + resets:
> + maxItems: 1
> +
> + clocks:
> + description:
> + Input clock for registers access
> + maxItems: 1
> +
> + additionalProperties: false
> +
> + required:
> + - compatible
> + - reg
> + - interrupts
> + - resets
> +
> +examples:
> + - |
> + #include <dt-bindings/clock/stm32fx-clock.h>
> + #include <dt-bindings/mfd/stm32f4-rcc.h>
> +
> + can: can@40006400 {
> + compatible = "st,stm32f4-bxcan-core";
> + reg = <0x40006400 0x800>;
> + resets = <&rcc STM32F4_APB1_RESET(CAN1)>;
> + clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN1)>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
Missing 'ranges'.
> + can1: can@0 {
> + compatible = "st,stm32f4-bxcan";
> + reg = <0x0>;
> + interrupts = <19>, <20>, <21>, <22>;
> + interrupt-names = "tx", "rx0", "rx1", "sce";
> + resets = <&rcc STM32F4_APB1_RESET(CAN1)>;
> + st,can-master;
No clocks?
> + };
> +
> + can2: can@400 {
> + compatible = "st,stm32f4-bxcan";
> + reg = <0x400>;
> + interrupts = <63>, <64>, <65>, <66>;
> + interrupt-names = "tx", "rx0", "rx1", "sce";
> + resets = <&rcc STM32F4_APB1_RESET(CAN2)>;
> + clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN2)>;
> + };
> + };
> --
> 2.32.0
>
>
Hi Krzysztof,
On Tue, Aug 23, 2022 at 3:41 PM Krzysztof Kozlowski
<[email protected]> wrote:
>
> On 20/08/2022 11:29, Dario Binacchi wrote:
> > Add documentation of device tree bindings for the STM32 basic extended
> > CAN (bxcan) controller.
> >
> > Signed-off-by: Dario Binacchi <[email protected]>
> > Signed-off-by: Dario Binacchi <[email protected]>
> >
> > ---
> >
> > Changes in v2:
> > - Change the file name into 'st,stm32-bxcan-core.yaml'.
> > - Rename compatibles:
> > - st,stm32-bxcan-core -> st,stm32f4-bxcan-core
> > - st,stm32-bxcan -> st,stm32f4-bxcan
> > - Rename master property to st,can-master.
> > - Remove the status property from the example.
> > - Put the node child properties as required.
> >
> > .../bindings/net/can/st,stm32-bxcan.yaml | 136 ++++++++++++++++++
> > 1 file changed, 136 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
> > new file mode 100644
> > index 000000000000..288631b5556d
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
> > @@ -0,0 +1,136 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/net/can/st,stm32-bxcan.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: STMicroelectronics bxCAN controller
> > +
> > +description: STMicroelectronics BxCAN controller for CAN bus
> > +
> > +maintainers:
> > + - Dario Binacchi <[email protected]>
> > +
> > +allOf:
> > + - $ref: can-controller.yaml#
> > +
> > +properties:
> > + compatible:
> > + enum:
> > + - st,stm32f4-bxcan-core
> > +
> > + reg:
> > + maxItems: 1
> > +
> > + resets:
> > + maxItems: 1
> > +
> > + clocks:
> > + description:
> > + Input clock for registers access
> > + maxItems: 1
> > +
> > + '#address-cells':
> > + const: 1
> > +
> > + '#size-cells':
> > + const: 0
> > +
> > +additionalProperties: false
> > +
> > +required:
> > + - compatible
> > + - reg
> > + - resets
> > + - clocks
> > + - '#address-cells'
> > + - '#size-cells'
> > +
> > +patternProperties:
>
> No improvements here, so my comment stay. Please fix it.
Sorry, I'ff fix it in version 3.
>
>
> > + "^can@[0-9]+$":
> > + type: object
> > + description:
> > + A CAN block node contains two subnodes, representing each one a CAN
> > + instance available on the machine.
>
> I still do not understand why you need children. You did not CC me on
> driver change, so difficult to say. You did not describe the parent
On the next submissions I'll send you all the series patches.
> device - there is no description.
Ok, I'll do it.
> Why do you need parent device at all?
> This looks like some driver-driven-bindings instead of just real
> hardware description.
The two devices are not independent.
As described in the reference manual RM0386 (STM32F469xx and STM32F479xx
advanced Arm®-based 32-bit MCUs) in paragraph 34.2, the bxCAN controller is a
dual CAN peripheral configuration:
• CAN1: Master bxCAN for managing the communication between a Slave bxCAN and
the 512-byte SRAM memory
• CAN2: Slave bxCAN, with no direct access to the SRAM memory.
So, if I want to use CAN2 only (and not CAN1), I need to be able to use shared
resources with CAN1 without having to probe the CAN1 driver. IMHO here is the
justification of the parent node.
Thanks and regards,
Dario
>
> Best regards,
> Krzysztof
--
Dario Binacchi
Embedded Linux Developer
[email protected]
__________________________________
Amarula Solutions SRL
Via Le Canevare 30, 31100 Treviso, Veneto, IT
T. +39 042 243 5310
[email protected]
http://www.amarulasolutions.com
Hi Rob,
On Thu, Aug 25, 2022 at 11:12 PM Rob Herring <[email protected]> wrote:
>
> On Sat, Aug 20, 2022 at 10:29:33AM +0200, Dario Binacchi wrote:
> > Add documentation of device tree bindings for the STM32 basic extended
> > CAN (bxcan) controller.
> >
> > Signed-off-by: Dario Binacchi <[email protected]>
> > Signed-off-by: Dario Binacchi <[email protected]>
> >
> > ---
> >
> > Changes in v2:
> > - Change the file name into 'st,stm32-bxcan-core.yaml'.
> > - Rename compatibles:
> > - st,stm32-bxcan-core -> st,stm32f4-bxcan-core
> > - st,stm32-bxcan -> st,stm32f4-bxcan
> > - Rename master property to st,can-master.
> > - Remove the status property from the example.
> > - Put the node child properties as required.
> >
> > .../bindings/net/can/st,stm32-bxcan.yaml | 136 ++++++++++++++++++
> > 1 file changed, 136 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
> > new file mode 100644
> > index 000000000000..288631b5556d
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
> > @@ -0,0 +1,136 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/net/can/st,stm32-bxcan.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: STMicroelectronics bxCAN controller
> > +
> > +description: STMicroelectronics BxCAN controller for CAN bus
> > +
> > +maintainers:
> > + - Dario Binacchi <[email protected]>
> > +
> > +allOf:
> > + - $ref: can-controller.yaml#
> > +
> > +properties:
> > + compatible:
> > + enum:
> > + - st,stm32f4-bxcan-core
> > +
> > + reg:
> > + maxItems: 1
> > +
> > + resets:
> > + maxItems: 1
> > +
> > + clocks:
> > + description:
> > + Input clock for registers access
> > + maxItems: 1
> > +
> > + '#address-cells':
> > + const: 1
> > +
> > + '#size-cells':
> > + const: 0
> > +
> > +additionalProperties: false
> > +
> > +required:
> > + - compatible
> > + - reg
> > + - resets
> > + - clocks
> > + - '#address-cells'
> > + - '#size-cells'
> > +
> > +patternProperties:
> > + "^can@[0-9]+$":
> > + type: object
> > + description:
> > + A CAN block node contains two subnodes, representing each one a CAN
> > + instance available on the machine.
> > +
> > + properties:
> > + compatible:
> > + enum:
> > + - st,stm32f4-bxcan
> > +
> > + st,can-master:
> > + description:
> > + Master and slave mode of the bxCAN peripheral is only relevant
> > + if the chip has two CAN peripherals. In that case they share
> > + some of the required logic, and that means you cannot use the
> > + slave CAN without the master CAN.
> > + type: boolean
> > +
> > + reg:
> > + description: |
> > + Offset of CAN instance in CAN block. Valid values are:
> > + - 0x0: CAN1
> > + - 0x400: CAN2
> > + maxItems: 1
> > +
> > + interrupts:
> > + items:
> > + - description: transmit interrupt
> > + - description: FIFO 0 receive interrupt
> > + - description: FIFO 1 receive interrupt
> > + - description: status change error interrupt
> > +
> > + interrupt-names:
> > + items:
> > + - const: tx
> > + - const: rx0
> > + - const: rx1
> > + - const: sce
> > +
> > + resets:
> > + maxItems: 1
> > +
> > + clocks:
> > + description:
> > + Input clock for registers access
> > + maxItems: 1
> > +
> > + additionalProperties: false
> > +
> > + required:
> > + - compatible
> > + - reg
> > + - interrupts
> > + - resets
> > +
> > +examples:
> > + - |
> > + #include <dt-bindings/clock/stm32fx-clock.h>
> > + #include <dt-bindings/mfd/stm32f4-rcc.h>
> > +
> > + can: can@40006400 {
> > + compatible = "st,stm32f4-bxcan-core";
> > + reg = <0x40006400 0x800>;
> > + resets = <&rcc STM32F4_APB1_RESET(CAN1)>;
> > + clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN1)>;
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > +
>
> Missing 'ranges'.
In the file arch/arm/boot/dts/stm32f429.dtsi, I didn't find any other
node using the 'ranges' property, so
I didn't use it for the CAN node either.
>
> > + can1: can@0 {
> > + compatible = "st,stm32f4-bxcan";
> > + reg = <0x0>;
> > + interrupts = <19>, <20>, <21>, <22>;
> > + interrupt-names = "tx", "rx0", "rx1", "sce";
> > + resets = <&rcc STM32F4_APB1_RESET(CAN1)>;
> > + st,can-master;
>
> No clocks?
It uses the parent node clock, since it is in master mode.
Thanks and regards,
Dario
>
> > + };
> > +
> > + can2: can@400 {
> > + compatible = "st,stm32f4-bxcan";
> > + reg = <0x400>;
> > + interrupts = <63>, <64>, <65>, <66>;
> > + interrupt-names = "tx", "rx0", "rx1", "sce";
> > + resets = <&rcc STM32F4_APB1_RESET(CAN2)>;
> > + clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN2)>;
> > + };
> > + };
> > --
> > 2.32.0
> >
> >
--
Dario Binacchi
Embedded Linux Developer
[email protected]
__________________________________
Amarula Solutions SRL
Via Le Canevare 30, 31100 Treviso, Veneto, IT
T. +39 042 243 5310
[email protected]
http://www.amarulasolutions.com
On Fri, Aug 26, 2022 at 2:27 AM Dario Binacchi
<[email protected]> wrote:
>
> Hi Rob,
>
> On Thu, Aug 25, 2022 at 11:12 PM Rob Herring <[email protected]> wrote:
> >
> > On Sat, Aug 20, 2022 at 10:29:33AM +0200, Dario Binacchi wrote:
> > > Add documentation of device tree bindings for the STM32 basic extended
> > > CAN (bxcan) controller.
> > >
> > > Signed-off-by: Dario Binacchi <[email protected]>
> > > Signed-off-by: Dario Binacchi <[email protected]>
> > >
> > > ---
> > >
> > > Changes in v2:
> > > - Change the file name into 'st,stm32-bxcan-core.yaml'.
> > > - Rename compatibles:
> > > - st,stm32-bxcan-core -> st,stm32f4-bxcan-core
> > > - st,stm32-bxcan -> st,stm32f4-bxcan
> > > - Rename master property to st,can-master.
> > > - Remove the status property from the example.
> > > - Put the node child properties as required.
> > >
> > > .../bindings/net/can/st,stm32-bxcan.yaml | 136 ++++++++++++++++++
> > > 1 file changed, 136 insertions(+)
> > > create mode 100644 Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
> > >
> > > diff --git a/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
> > > new file mode 100644
> > > index 000000000000..288631b5556d
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/net/can/st,stm32-bxcan.yaml
> > > @@ -0,0 +1,136 @@
> > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > > +%YAML 1.2
> > > +---
> > > +$id: http://devicetree.org/schemas/net/can/st,stm32-bxcan.yaml#
> > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > +
> > > +title: STMicroelectronics bxCAN controller
> > > +
> > > +description: STMicroelectronics BxCAN controller for CAN bus
> > > +
> > > +maintainers:
> > > + - Dario Binacchi <[email protected]>
> > > +
> > > +allOf:
> > > + - $ref: can-controller.yaml#
> > > +
> > > +properties:
> > > + compatible:
> > > + enum:
> > > + - st,stm32f4-bxcan-core
> > > +
> > > + reg:
> > > + maxItems: 1
> > > +
> > > + resets:
> > > + maxItems: 1
> > > +
> > > + clocks:
> > > + description:
> > > + Input clock for registers access
> > > + maxItems: 1
> > > +
> > > + '#address-cells':
> > > + const: 1
> > > +
> > > + '#size-cells':
> > > + const: 0
> > > +
> > > +additionalProperties: false
> > > +
> > > +required:
> > > + - compatible
> > > + - reg
> > > + - resets
> > > + - clocks
> > > + - '#address-cells'
> > > + - '#size-cells'
> > > +
> > > +patternProperties:
> > > + "^can@[0-9]+$":
> > > + type: object
> > > + description:
> > > + A CAN block node contains two subnodes, representing each one a CAN
> > > + instance available on the machine.
> > > +
> > > + properties:
> > > + compatible:
> > > + enum:
> > > + - st,stm32f4-bxcan
> > > +
> > > + st,can-master:
> > > + description:
> > > + Master and slave mode of the bxCAN peripheral is only relevant
> > > + if the chip has two CAN peripherals. In that case they share
> > > + some of the required logic, and that means you cannot use the
> > > + slave CAN without the master CAN.
> > > + type: boolean
> > > +
> > > + reg:
> > > + description: |
> > > + Offset of CAN instance in CAN block. Valid values are:
> > > + - 0x0: CAN1
> > > + - 0x400: CAN2
> > > + maxItems: 1
> > > +
> > > + interrupts:
> > > + items:
> > > + - description: transmit interrupt
> > > + - description: FIFO 0 receive interrupt
> > > + - description: FIFO 1 receive interrupt
> > > + - description: status change error interrupt
> > > +
> > > + interrupt-names:
> > > + items:
> > > + - const: tx
> > > + - const: rx0
> > > + - const: rx1
> > > + - const: sce
> > > +
> > > + resets:
> > > + maxItems: 1
> > > +
> > > + clocks:
> > > + description:
> > > + Input clock for registers access
> > > + maxItems: 1
> > > +
> > > + additionalProperties: false
> > > +
> > > + required:
> > > + - compatible
> > > + - reg
> > > + - interrupts
> > > + - resets
> > > +
> > > +examples:
> > > + - |
> > > + #include <dt-bindings/clock/stm32fx-clock.h>
> > > + #include <dt-bindings/mfd/stm32f4-rcc.h>
> > > +
> > > + can: can@40006400 {
> > > + compatible = "st,stm32f4-bxcan-core";
> > > + reg = <0x40006400 0x800>;
> > > + resets = <&rcc STM32F4_APB1_RESET(CAN1)>;
> > > + clocks = <&rcc 0 STM32F4_APB1_CLOCK(CAN1)>;
> > > + #address-cells = <1>;
> > > + #size-cells = <0>;
> > > +
> >
> > Missing 'ranges'.
>
> In the file arch/arm/boot/dts/stm32f429.dtsi, I didn't find any other
> node using the 'ranges' property, so
> I didn't use it for the CAN node either.
If the child node is a memory mapped address, then you need 'ranges'.
Otherwise, things like of_iomap() don't work.
Looking at the above file, only efuse@1fff7800 and adc@40012000 seem
to be cases also missing 'ranges'.
Rob