ASUS Transformers require this driver for proper work with their dock.
Dock is controlled by EC and its presence is detected by a GPIO.
---
Changes in v2:
- adjusted documentation
---
Michał Mirosław (1):
i2c: Add GPIO-based hotplug gate
Svyatoslav Ryhel (1):
dt-bindings: i2c: add binding for i2c-hotplug-gpio
.../bindings/i2c/i2c-hotplug-gpio.yaml | 65 +++++
drivers/i2c/Kconfig | 11 +
drivers/i2c/Makefile | 1 +
drivers/i2c/i2c-hotplug-gpio.c | 266 ++++++++++++++++++
4 files changed, 343 insertions(+)
create mode 100644 Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml
create mode 100644 drivers/i2c/i2c-hotplug-gpio.c
--
2.39.2
On 19/06/2023 17:37, Svyatoslav Ryhel wrote:
> ASUS Transformers require this driver for proper work with their dock.
> Dock is controlled by EC and its presence is detected by a GPIO.
>
> ---
> Changes in v2:
> - adjusted documentation
This is too generic. Everything can be adjustment. Be precise what you
did here. What changed?
Best regards,
Krzysztof
Document device tree schema which describes hot-pluggable via GPIO
i2c bus.
Signed-off-by: Svyatoslav Ryhel <[email protected]>
---
.../bindings/i2c/i2c-hotplug-gpio.yaml | 65 +++++++++++++++++++
1 file changed, 65 insertions(+)
create mode 100644 Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml
diff --git a/Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml b/Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml
new file mode 100644
index 000000000000..21f2b74ca6c1
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml
@@ -0,0 +1,65 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/i2c-hotplug-gpio.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: GPIO detected hot-plugged I2C bus
+
+maintainers:
+ - Michał Mirosław <[email protected]>
+
+description:
+ Driver for hot-plugged I2C busses, where some devices on a bus
+ are hot-pluggable and their presence is indicated by GPIO line.
+
+properties:
+ compatible:
+ items:
+ - const: i2c-hotplug-gpio
+
+ '#address-cells':
+ const: 1
+
+ '#size-cells':
+ const: 0
+
+ interrupts-extended:
+ minItems: 1
+
+ detect-gpios:
+ maxItems: 1
+
+ i2c-parent:
+ maxItems: 1
+
+required:
+ - compatible
+ - '#address-cells'
+ - '#size-cells'
+ - interrupts-extended
+ - detect-gpios
+ - i2c-parent
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ /*
+ * Asus Transformers use I2C hotplug for attachable dock keyboard
+ */
+ #include <dt-bindings/gpio/gpio.h>
+ #include <dt-bindings/interrupt-controller/irq.h>
+
+ i2c-dock {
+ compatible = "i2c-hotplug-gpio";
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ interrupts-extended = <&gpio 164 IRQ_TYPE_EDGE_BOTH>;
+ detect-gpios = <&gpio 164 GPIO_ACTIVE_LOW>;
+
+ i2c-parent = <&gen2_i2c>;
+ };
+...
--
2.39.2
On 19/06/2023 17:37, Svyatoslav Ryhel wrote:
> Document device tree schema which describes hot-pluggable via GPIO
> i2c bus.
>
> Signed-off-by: Svyatoslav Ryhel <[email protected]>
1. Don't send new version before discussion finishes. v2 after one hour
is definitely not enough. Usually one day.
2. Test the patches before sending...
What changed here?
> ---
> .../bindings/i2c/i2c-hotplug-gpio.yaml | 65 +++++++++++++++++++
> 1 file changed, 65 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml
>
> diff --git a/Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml b/Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml
> new file mode 100644
> index 000000000000..21f2b74ca6c1
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml
> @@ -0,0 +1,65 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/i2c/i2c-hotplug-gpio.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: GPIO detected hot-plugged I2C bus
> +
> +maintainers:
> + - Michał Mirosław <[email protected]>
> +
> +description:
> + Driver for hot-plugged I2C busses, where some devices on a bus
"Driver" so SW? Bindings are for hardware, not for drivers.
> + are hot-pluggable and their presence is indicated by GPIO line.
> +
> +properties:
> + compatible:
> + items:
Drop items.
> + - const: i2c-hotplug-gpio
> +
> + '#address-cells':
> + const: 1
> +
> + '#size-cells':
> + const: 0
> +
> + interrupts-extended:
I missed last time - this is wrong. Just interrupts.
> + minItems: 1
maxItems
> +
> + detect-gpios:
> + maxItems: 1
> +
> + i2c-parent:
> + maxItems: 1
Discussion from v1 stands - this is a software construct, not a real device.
> +
> +required:
> + - compatible
> + - '#address-cells'
> + - '#size-cells'
> + - interrupts-extended
> + - detect-gpios
> + - i2c-parent
> +
> +unevaluatedProperties: false
instead additionalProperties: false
Anyway, don't send v3, before the discussion about the entire concept
finishes. You create a software/virtual device, instead of adding these
properties to bindings for a real hardware.
> +
> +examples:
> + - |
> + /*
> + * Asus Transformers use I2C hotplug for attachable dock keyboard
> + */
> + #include <dt-bindings/gpio/gpio.h>
> + #include <dt-bindings/interrupt-controller/irq.h>
> +
> + i2c-dock {
> + compatible = "i2c-hotplug-gpio";
> +
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + interrupts-extended = <&gpio 164 IRQ_TYPE_EDGE_BOTH>;
> + detect-gpios = <&gpio 164 GPIO_ACTIVE_LOW>;
I don't think you can have both interrupt and GPIO on the same line.
> +
> + i2c-parent = <&gen2_i2c>;
> + };
> +...
Best regards,
Krzysztof
On 19/06/2023 17:52, Svyatoslav Ryhel wrote:
> пн, 19 черв. 2023 р. о 18:49 Krzysztof Kozlowski
> <[email protected]> пише:
>>
>> On 19/06/2023 17:37, Svyatoslav Ryhel wrote:
>>> ASUS Transformers require this driver for proper work with their dock.
>>> Dock is controlled by EC and its presence is detected by a GPIO.
>>>
>>> ---
>>> Changes in v2:
>>> - adjusted documentation
>>
>> This is too generic. Everything can be adjustment. Be precise what you
>> did here. What changed?
>>
>
> Everything that you asked for.
And how other people can know it? That's not a proper changelog.
What changed? If you are going to ignore writing proper changelogs, I am
going to ignore patches.
Best regards,
Krzysztof
пн, 19 черв. 2023 р. о 18:49 Krzysztof Kozlowski
<[email protected]> пише:
>
> On 19/06/2023 17:37, Svyatoslav Ryhel wrote:
> > ASUS Transformers require this driver for proper work with their dock.
> > Dock is controlled by EC and its presence is detected by a GPIO.
> >
> > ---
> > Changes in v2:
> > - adjusted documentation
>
> This is too generic. Everything can be adjustment. Be precise what you
> did here. What changed?
>
Everything that you asked for.
> Best regards,
> Krzysztof
>
On Mon, Jun 19, 2023 at 05:53:24PM +0200, Krzysztof Kozlowski wrote:
> On 19/06/2023 17:37, Svyatoslav Ryhel wrote:
> > Document device tree schema which describes hot-pluggable via GPIO
> > i2c bus.
> >
> > Signed-off-by: Svyatoslav Ryhel <[email protected]>
[...]
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/i2c/i2c-hotplug-gpio.yaml
> > @@ -0,0 +1,65 @@
> > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/i2c/i2c-hotplug-gpio.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: GPIO detected hot-plugged I2C bus
> > +
> > +maintainers:
> > + - Micha? Miros?aw <[email protected]>
> > +
> > +description:
> > + Driver for hot-plugged I2C busses, where some devices on a bus
>
> "Driver" so SW? Bindings are for hardware, not for drivers.
[...]
> > + detect-gpios:
> > + maxItems: 1
> > +
> > + i2c-parent:
> > + maxItems: 1
>
> Discussion from v1 stands - this is a software construct, not a real device.
[...]
> Anyway, don't send v3, before the discussion about the entire concept
> finishes. You create a software/virtual device, instead of adding these
> properties to bindings for a real hardware.
Hi,
In this case it's hard for me to tell the difference if this is
real or virtual hardware.
The Transformers have a connector that's used for USB, charging or
for attaching a keyboard (called a dock; it also has a battery and
a touchpad). This connector probably (I don't have the means to verify
that) has an I2C bus lines and a "detect" line (pulled low on the dock
side) among the pins. I guess there is either no additional chip or
a transparent bridge/buffer chip, but nothing that could be controlled
by software. For DT this setup could be modelled like an I2C gate or
2-port mux with enable joining two I2C busses (one "closer" to the
CPU -- parent).
> > +
> > +examples:
> > + - |
> > + /*
> > + * Asus Transformers use I2C hotplug for attachable dock keyboard
> > + */
> > + #include <dt-bindings/gpio/gpio.h>
> > + #include <dt-bindings/interrupt-controller/irq.h>
> > +
> > + i2c-dock {
> > + compatible = "i2c-hotplug-gpio";
> > +
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > +
> > + interrupts-extended = <&gpio 164 IRQ_TYPE_EDGE_BOTH>;
> > + detect-gpios = <&gpio 164 GPIO_ACTIVE_LOW>;
>
> I don't think you can have both interrupt and GPIO on the same line.
This actually works as expected. There are multiple devices (and
drivers) that depend on this, e.g. matrix-keypad and gpio-keys.
Best Regards
Micha? Miros?aw
Hi Svyatoslav,
On Mon, Jun 19, 2023 at 06:52:50PM +0300, Svyatoslav Ryhel wrote:
> пн, 19 черв. 2023 р. о 18:49 Krzysztof Kozlowski
> <[email protected]> пише:
> >
> > On 19/06/2023 17:37, Svyatoslav Ryhel wrote:
> > > ASUS Transformers require this driver for proper work with their dock.
> > > Dock is controlled by EC and its presence is detected by a GPIO.
> > >
> > > ---
> > > Changes in v2:
> > > - adjusted documentation
> >
> > This is too generic. Everything can be adjustment. Be precise what you
> > did here. What changed?
> >
>
> Everything that you asked for.
please list all the changes you made trying to be as more
specific as you can.
You make life to reviewers easier.
Thanks,
Andi