diff mbox series

[1/6] dt-bindings: mfd: Add ST Multi-Function eXpander driver

Message ID 1518100057-23234-2-git-send-email-amelie.delaunay@st.com
State New
Headers show
Series Introduce STMicroelectronics MultiFunction eXpander | expand

Commit Message

Amelie DELAUNAY Feb. 8, 2018, 2:27 p.m. UTC
This patch adds documentation of device tree bindings for the
STMicroelectronics Multi-Function eXpander (MFX).

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
---
 Documentation/devicetree/bindings/mfd/st-mfx.txt | 51 ++++++++++++++++++++++++
 1 file changed, 51 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mfd/st-mfx.txt

Comments

Rob Herring Feb. 18, 2018, 11:19 p.m. UTC | #1
On Thu, Feb 08, 2018 at 03:27:32PM +0100, Amelie Delaunay wrote:
> This patch adds documentation of device tree bindings for the
> STMicroelectronics Multi-Function eXpander (MFX).
> 
> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
> ---
>  Documentation/devicetree/bindings/mfd/st-mfx.txt | 51 ++++++++++++++++++++++++
>  1 file changed, 51 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mfd/st-mfx.txt
> 
> diff --git a/Documentation/devicetree/bindings/mfd/st-mfx.txt b/Documentation/devicetree/bindings/mfd/st-mfx.txt
> new file mode 100644
> index 0000000..423d800
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/st-mfx.txt
> @@ -0,0 +1,51 @@
> +STMicroelectronics Multi-Function eXpander
> +
> +ST Multi-Function eXpander (MFX) is a slave controller using I2C for
> +communication with the main MCU. Its main features are gpio expansion, main
> +MCU IDD measurement (IDD is the amount of current that flows through VDD)
> +and resistive touchscreen controller.

You don't have to implement all the drivers now, but please completely 
describe the device. As is, there is no reason to have a child GPIO 
node.

> +
> +Required properties:
> +- compatible: must be "st,mfx"

Kind of generic. Only 1 single version ever?

> +- reg: I2C address of the device
> +- interrupts: interrupt triggered by MFX_IRQ_OUT signal
> +- interrupt-parent: interrupt controller MFX is connected to
> +- interrupt-controller: marks the device as an interrupt controller
> +- #interrupt-cells: should be <1>, index of the interrupt within the
> +  controller, in accordance with the "one cell" variant of
> +  <devicetree/bindings/interrupt-controller/interrupt.txt>
> +
> +Optional nodes:
> +
> +* GPIO eXpander
> +MFX provides 16 programmable GPIOs, and it is also possible to recover 8
> +alternate GPIOs if the main functions are not used (touchscreen controller and
> +IDD measurement not enabled).
> +
> +Required properties:
> +- compatible : must be "st,mfx-gpio"
> +- interrupt-parent : must be <&mfx>

Not necessary. A parent node with 'interrupt-controller' property is the 
interrupt's parent.

> +- interrupts = must be <0>
> +- gpio-controller: marks the device node as a GPIO controller
> +- #gpio-cells: should be <2>, the first cell is the GPIO offset on this GPIO
> +  controller, the second cell is the gpio flags in accordance with
> +  <dt-bindings/gpio/st-mfx-gpio.h>.

Custom flags? Use standard flags.

DT binding headers should be part of this patch.

> +
> +Example:
> +
> +	mfx: mfx@42 {
> +		compatible = "st,mfx";
> +		reg = <0x42>;
> +		interrupts = <8 IRQ_TYPE_EDGE_RISING>;
> +		interrupt-parent = <&gpioi>;
> +		interrupt-controller;
> +		#interrupt-cells = <1>;
> +
> +		mfxgpio: mfx_gpio {

gpio {

> +			compatible = "st,mfx-gpio";
> +			interrupt-parent = <&mfx>;
> +			interrupts = <0>;
> +			gpio-controller;
> +			#gpio-cells = <2>;
> +		};
> +	};
> -- 
> 2.7.4
> 
--
To unsubscribe from this list: send the line "unsubscribe linux-gpio" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Amelie DELAUNAY Feb. 19, 2018, 3:59 p.m. UTC | #2
On 02/19/2018 12:19 AM, Rob Herring wrote:
> On Thu, Feb 08, 2018 at 03:27:32PM +0100, Amelie Delaunay wrote:

>> This patch adds documentation of device tree bindings for the

>> STMicroelectronics Multi-Function eXpander (MFX).

>>

>> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>

>> ---

>>   Documentation/devicetree/bindings/mfd/st-mfx.txt | 51 ++++++++++++++++++++++++

>>   1 file changed, 51 insertions(+)

>>   create mode 100644 Documentation/devicetree/bindings/mfd/st-mfx.txt

>>

>> diff --git a/Documentation/devicetree/bindings/mfd/st-mfx.txt b/Documentation/devicetree/bindings/mfd/st-mfx.txt

>> new file mode 100644

>> index 0000000..423d800

>> --- /dev/null

>> +++ b/Documentation/devicetree/bindings/mfd/st-mfx.txt

>> @@ -0,0 +1,51 @@

>> +STMicroelectronics Multi-Function eXpander

>> +

>> +ST Multi-Function eXpander (MFX) is a slave controller using I2C for

>> +communication with the main MCU. Its main features are gpio expansion, main

>> +MCU IDD measurement (IDD is the amount of current that flows through VDD)

>> +and resistive touchscreen controller.

> 

> You don't have to implement all the drivers now, but please completely

> describe the device. As is, there is no reason to have a child GPIO

> node.

>

The MFD driver will be abandoned as only GPIO part is used. I'll send a 
V2 soon.
>> +

>> +Required properties:

>> +- compatible: must be "st,mfx"

> 

> Kind of generic. Only 1 single version ever?

> 

"st-mfx" compatible will disappear in V2 (we keep only GPIO driver). MFX 
version can be read in MFX FW_VERSION register. So do I keep 
"st,mfx-gpio" compatible or you want to see mfx version ?

>> +- reg: I2C address of the device

>> +- interrupts: interrupt triggered by MFX_IRQ_OUT signal

>> +- interrupt-parent: interrupt controller MFX is connected to

>> +- interrupt-controller: marks the device as an interrupt controller

>> +- #interrupt-cells: should be <1>, index of the interrupt within the

>> +  controller, in accordance with the "one cell" variant of

>> +  <devicetree/bindings/interrupt-controller/interrupt.txt>

>> +

>> +Optional nodes:

>> +

>> +* GPIO eXpander

>> +MFX provides 16 programmable GPIOs, and it is also possible to recover 8

>> +alternate GPIOs if the main functions are not used (touchscreen controller and

>> +IDD measurement not enabled).

>> +

>> +Required properties:

>> +- compatible : must be "st,mfx-gpio"

>> +- interrupt-parent : must be <&mfx>

> 

> Not necessary. A parent node with 'interrupt-controller' property is the

> interrupt's parent.

> 

I will keep it in mind.
>> +- interrupts = must be <0>

>> +- gpio-controller: marks the device node as a GPIO controller

>> +- #gpio-cells: should be <2>, the first cell is the GPIO offset on this GPIO

>> +  controller, the second cell is the gpio flags in accordance with

>> +  <dt-bindings/gpio/st-mfx-gpio.h>.

> 

> Custom flags? Use standard flags.

> 

> DT binding headers should be part of this patch.

> 

Custom flags because MFX GPIOs have several types:
- Output open drain with internal pull-up resistor
- Output open drain without internal pull-up resistor
- Output push pull without internal pull resistor
- Input with internal pull-up resistor
- Input with internal pull-down resistor
- Input floating
- Input analog.
Standard flags don't have pull up or down information. That's why I am 
using custom flags, they overloads standard flags.
I will add DT bindings header in this patch V2.
>> +

>> +Example:

>> +

>> +	mfx: mfx@42 {

>> +		compatible = "st,mfx";

>> +		reg = <0x42>;

>> +		interrupts = <8 IRQ_TYPE_EDGE_RISING>;

>> +		interrupt-parent = <&gpioi>;

>> +		interrupt-controller;

>> +		#interrupt-cells = <1>;

>> +

>> +		mfxgpio: mfx_gpio {

> 

> gpio {

> 

OK. Will change it in V2.

Thanks,
Amelie
>> +			compatible = "st,mfx-gpio";

>> +			interrupt-parent = <&mfx>;

>> +			interrupts = <0>;

>> +			gpio-controller;

>> +			#gpio-cells = <2>;

>> +		};

>> +	};

>> -- 

>> 2.7.4

>>
Rob Herring Feb. 22, 2018, 12:06 a.m. UTC | #3
On Mon, Feb 19, 2018 at 9:59 AM, Amelie DELAUNAY <amelie.delaunay@st.com> wrote:
>
>
> On 02/19/2018 12:19 AM, Rob Herring wrote:
>> On Thu, Feb 08, 2018 at 03:27:32PM +0100, Amelie Delaunay wrote:
>>> This patch adds documentation of device tree bindings for the
>>> STMicroelectronics Multi-Function eXpander (MFX).
>>>
>>> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
>>> ---
>>>   Documentation/devicetree/bindings/mfd/st-mfx.txt | 51 ++++++++++++++++++++++++
>>>   1 file changed, 51 insertions(+)
>>>   create mode 100644 Documentation/devicetree/bindings/mfd/st-mfx.txt
>>>
>>> diff --git a/Documentation/devicetree/bindings/mfd/st-mfx.txt b/Documentation/devicetree/bindings/mfd/st-mfx.txt
>>> new file mode 100644
>>> index 0000000..423d800
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/mfd/st-mfx.txt
>>> @@ -0,0 +1,51 @@
>>> +STMicroelectronics Multi-Function eXpander
>>> +
>>> +ST Multi-Function eXpander (MFX) is a slave controller using I2C for
>>> +communication with the main MCU. Its main features are gpio expansion, main
>>> +MCU IDD measurement (IDD is the amount of current that flows through VDD)
>>> +and resistive touchscreen controller.
>>
>> You don't have to implement all the drivers now, but please completely
>> describe the device. As is, there is no reason to have a child GPIO
>> node.
>>
> The MFD driver will be abandoned as only GPIO part is used. I'll send a
> V2 soon.
>>> +
>>> +Required properties:
>>> +- compatible: must be "st,mfx"
>>
>> Kind of generic. Only 1 single version ever?
>>
> "st-mfx" compatible will disappear in V2 (we keep only GPIO driver). MFX
> version can be read in MFX FW_VERSION register. So do I keep
> "st,mfx-gpio" compatible or you want to see mfx version ?

That sounds a bit worrying. The other functions will *never* get
accessed? The DT should reflect the h/w including any future needs,
not just what you have a driver for today.

>>> +- reg: I2C address of the device
>>> +- interrupts: interrupt triggered by MFX_IRQ_OUT signal
>>> +- interrupt-parent: interrupt controller MFX is connected to
>>> +- interrupt-controller: marks the device as an interrupt controller
>>> +- #interrupt-cells: should be <1>, index of the interrupt within the
>>> +  controller, in accordance with the "one cell" variant of
>>> +  <devicetree/bindings/interrupt-controller/interrupt.txt>
>>> +
>>> +Optional nodes:
>>> +
>>> +* GPIO eXpander
>>> +MFX provides 16 programmable GPIOs, and it is also possible to recover 8
>>> +alternate GPIOs if the main functions are not used (touchscreen controller and
>>> +IDD measurement not enabled).
>>> +
>>> +Required properties:
>>> +- compatible : must be "st,mfx-gpio"
>>> +- interrupt-parent : must be <&mfx>
>>
>> Not necessary. A parent node with 'interrupt-controller' property is the
>> interrupt's parent.
>>
> I will keep it in mind.
>>> +- interrupts = must be <0>
>>> +- gpio-controller: marks the device node as a GPIO controller
>>> +- #gpio-cells: should be <2>, the first cell is the GPIO offset on this GPIO
>>> +  controller, the second cell is the gpio flags in accordance with
>>> +  <dt-bindings/gpio/st-mfx-gpio.h>.
>>
>> Custom flags? Use standard flags.
>>
>> DT binding headers should be part of this patch.
>>
> Custom flags because MFX GPIOs have several types:
> - Output open drain with internal pull-up resistor
> - Output open drain without internal pull-up resistor
> - Output push pull without internal pull resistor
> - Input with internal pull-up resistor
> - Input with internal pull-down resistor
> - Input floating
> - Input analog.
> Standard flags don't have pull up or down information. That's why I am
> using custom flags, they overloads standard flags.

I'll leave this one to Linus to comment on.

> I will add DT bindings header in this patch V2.
--
To unsubscribe from this list: send the line "unsubscribe linux-gpio" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Linus Walleij Feb. 22, 2018, 1:11 p.m. UTC | #4
On Thu, Feb 8, 2018 at 3:27 PM, Amelie Delaunay <amelie.delaunay@st.com> wrote:

> +Required properties:
> +- compatible: must be "st,mfx"

I bet this should be more specific. Tomorrow there will be a new
version of this expander and then we will wish that we used
a more specific compatible for the first one.

Does this chip have any kind of product number on it?

Else I would be tempted to use the compatible "st,mfx-0000"
or something, indicating it is the first of its kind.

> +- reg: I2C address of the device
> +- interrupts: interrupt triggered by MFX_IRQ_OUT signal
> +- interrupt-parent: interrupt controller MFX is connected to
> +- interrupt-controller: marks the device as an interrupt controller
> +- #interrupt-cells: should be <1>, index of the interrupt within the
> +  controller, in accordance with the "one cell" variant of
> +  <devicetree/bindings/interrupt-controller/interrupt.txt>

Seems fine.

> +Optional nodes:
> +
> +* GPIO eXpander
> +MFX provides 16 programmable GPIOs, and it is also possible to recover 8
> +alternate GPIOs if the main functions are not used (touchscreen controller and
> +IDD measurement not enabled).

Apparenly Rob thinks this should go elsewhere.

> +- gpio-controller: marks the device node as a GPIO controller
> +- #gpio-cells: should be <2>, the first cell is the GPIO offset on this GPIO
> +  controller, the second cell is the gpio flags in accordance with
> +  <dt-bindings/gpio/st-mfx-gpio.h>.

Let's discuss these extra GPIO flag bindings separately.

Yours,
Linus Walleij
--
To unsubscribe from this list: send the line "unsubscribe linux-gpio" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Linus Walleij Feb. 22, 2018, 1:22 p.m. UTC | #5
On Mon, Feb 19, 2018 at 4:59 PM, Amelie DELAUNAY <amelie.delaunay@st.com> wrote:
> On 02/19/2018 12:19 AM, Rob Herring wrote:
>> On Thu, Feb 08, 2018 at 03:27:32PM +0100, Amelie Delaunay wrote:

>>> +- interrupts = must be <0>
>>> +- gpio-controller: marks the device node as a GPIO controller
>>> +- #gpio-cells: should be <2>, the first cell is the GPIO offset on this GPIO
>>> +  controller, the second cell is the gpio flags in accordance with
>>> +  <dt-bindings/gpio/st-mfx-gpio.h>.
>>
>> Custom flags? Use standard flags.
>>
>> DT binding headers should be part of this patch.
>>
> Custom flags because MFX GPIOs have several types:
> - Output open drain with internal pull-up resistor
> - Output open drain without internal pull-up resistor
> - Output push pull without internal pull resistor
> - Input with internal pull-up resistor
> - Input with internal pull-down resistor
> - Input floating
> - Input analog.
> Standard flags don't have pull up or down information. That's why I am
> using custom flags, they overloads standard flags.

This is because pull up/down and tristate/high z (floating)
also known as PIN_CONFIG_BIAS_HIGH_IMPEDANCE,
is controlled by the pin control subsystem, not GPIO.

If your hardware does even more pin control (like multiplexing)
then I suggest that you create a pin control driver back-end for
this and put the resulting driver in drivers/pinctrl.

Some recent additions of expanders in drivers/pinctrl makes
for great inspiration for this work. See for example:
drivers/pinctrl/pinctrl-sx150x.c
drivers/pinctrl/pinctrl-mcp23s08.c

These are both combined pin control and GPIO drivers that
we moved from drivers/gpio because we concluded that they
do more than just GPIO. The GPIO lines are matches to
pins using the GPIO ranges from the call to
gpiochip_add_pin_range() and using gpiochip_generic_config()
as the gpiochip .set_config() callback.

It has been discussed to expose subsets of pin config to
GPIO. Indeed, we already handle open drain/source and
debounce by simply calling into the pin control back-end
or handling it directly in the GPIO driver using the standard
pin config properties.

I am reluctant about this, I think the split of responsibilities
is pretty nice.

I'd recommend looking at the sx150x pin control driver and
check if you can maybe take this direction with the patch?

Yours,
Linus Walleij
--
To unsubscribe from this list: send the line "unsubscribe linux-gpio" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Amelie DELAUNAY Feb. 22, 2018, 3:15 p.m. UTC | #6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--
To unsubscribe from this list: send the line "unsubscribe linux-gpio" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Amelie DELAUNAY Feb. 22, 2018, 3:19 p.m. UTC | #7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--
To unsubscribe from this list: send the line "unsubscribe linux-gpio" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/mfd/st-mfx.txt b/Documentation/devicetree/bindings/mfd/st-mfx.txt
new file mode 100644
index 0000000..423d800
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/st-mfx.txt
@@ -0,0 +1,51 @@ 
+STMicroelectronics Multi-Function eXpander
+
+ST Multi-Function eXpander (MFX) is a slave controller using I2C for
+communication with the main MCU. Its main features are gpio expansion, main
+MCU IDD measurement (IDD is the amount of current that flows through VDD)
+and resistive touchscreen controller.
+
+Required properties:
+- compatible: must be "st,mfx"
+- reg: I2C address of the device
+- interrupts: interrupt triggered by MFX_IRQ_OUT signal
+- interrupt-parent: interrupt controller MFX is connected to
+- interrupt-controller: marks the device as an interrupt controller
+- #interrupt-cells: should be <1>, index of the interrupt within the
+  controller, in accordance with the "one cell" variant of
+  <devicetree/bindings/interrupt-controller/interrupt.txt>
+
+Optional nodes:
+
+* GPIO eXpander
+MFX provides 16 programmable GPIOs, and it is also possible to recover 8
+alternate GPIOs if the main functions are not used (touchscreen controller and
+IDD measurement not enabled).
+
+Required properties:
+- compatible : must be "st,mfx-gpio"
+- interrupt-parent : must be <&mfx>
+- interrupts = must be <0>
+- gpio-controller: marks the device node as a GPIO controller
+- #gpio-cells: should be <2>, the first cell is the GPIO offset on this GPIO
+  controller, the second cell is the gpio flags in accordance with
+  <dt-bindings/gpio/st-mfx-gpio.h>.
+
+Example:
+
+	mfx: mfx@42 {
+		compatible = "st,mfx";
+		reg = <0x42>;
+		interrupts = <8 IRQ_TYPE_EDGE_RISING>;
+		interrupt-parent = <&gpioi>;
+		interrupt-controller;
+		#interrupt-cells = <1>;
+
+		mfxgpio: mfx_gpio {
+			compatible = "st,mfx-gpio";
+			interrupt-parent = <&mfx>;
+			interrupts = <0>;
+			gpio-controller;
+			#gpio-cells = <2>;
+		};
+	};