[PATCH V2 0/2] input: rotary-encoder: Support key events

[PATCH V2 0/2] input: rotary-encoder: Support key events

[Donghoon Han]

This patchset supports generating EV_KEY, instead of EV_REL.

An example could be a volume knob, with key events:
 - KEY_VOLUMEDOWN / KEY_VOLUMEUP

[tested on imx6q platform,  full period, half period]

Donghoon Han (2):
    Input: rotary_encoder - Support key events
    Input: rotaty-encoder - Add DT binding document

 Documentation/devicetree/bindings/input/rotary-encoder.txt | 12 ++++++++++++
 drivers/input/misc/rotary_encoder.c                        | 24 ++++++++++++++++++++++--
 2 files changed, 34 insertions(+), 2 deletions(-)

[PATCH V2 1/2] Input: rotary_encoder - Support key events

[Donghoon Han]

From: Steven Han <nazgul33@gmail.com>

Support generating EV_KEY pair, instead of EV_REL.

Signed-off-by: Donghoon Han <nazgul33@gmail.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Daniel Mack <daniel@caiaq.de>
To: linux-input@vger.kernel.org
---
V2: added missing input_sync()
---
 drivers/input/misc/rotary_encoder.c | 24 ++++++++++++++++++++++--
 1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/drivers/input/misc/rotary_encoder.c b/drivers/input/misc/rotary_encoder.c
index 72eee6d55527..0014a7d9f8f9 100644
--- a/drivers/input/misc/rotary_encoder.c
+++ b/drivers/input/misc/rotary_encoder.c
@@ -41,6 +41,8 @@ struct rotary_encoder {
 	u32 steps;
 	u32 axis;
 	bool relative_axis;
+	bool relative_keys;
+	u32 keycodes[2];
 	bool rollover;
 	enum rotary_encoder_encoding encoding;
 
@@ -79,6 +81,11 @@ static void rotary_encoder_report_event(struct rotary_encoder *encoder)
 	if (encoder->relative_axis) {
 		input_report_rel(encoder->input,
 				 encoder->axis, encoder->dir);
+	} else if (encoder->relative_keys) {
+		u32 keycode = encoder->keycodes[encoder->dir > 0];
+		input_event(encoder->input, EV_KEY, keycode, 1);
+		input_sync(encoder->input);
+		input_event(encoder->input, EV_KEY, keycode, 0);
 	} else {
 		unsigned int pos = encoder->pos;
 
@@ -237,6 +244,16 @@ static int rotary_encoder_probe(struct platform_device *pdev)
 	device_property_read_u32(dev, "linux,axis", &encoder->axis);
 	encoder->relative_axis =
 		device_property_read_bool(dev, "rotary-encoder,relative-axis");
+	encoder->relative_keys =
+		device_property_read_bool(dev, "rotary-encoder,relative-keys");
+	if (encoder->relative_keys) {
+		err = device_property_read_u32_array(dev,
+					"rotary-encoder,relative-keycodes",
+					encoder->keycodes, 2);
+		if (err)
+			dev_err(dev, "unable to get keycodes: %d\n", err);
+		return err;
+	}
 
 	encoder->gpios = devm_gpiod_get_array(dev, NULL, GPIOD_IN);
 	if (IS_ERR(encoder->gpios)) {
@@ -260,9 +277,12 @@ static int rotary_encoder_probe(struct platform_device *pdev)
 	input->id.bustype = BUS_HOST;
 	input->dev.parent = dev;
 
-	if (encoder->relative_axis)
+	if (encoder->relative_axis) {
 		input_set_capability(input, EV_REL, encoder->axis);
-	else
+	} else if (encoder->relative_keys) {
+		input_set_capability(input, EV_KEY, encoder->keycodes[0]);
+		input_set_capability(input, EV_KEY, encoder->keycodes[1]);
+	} else
 		input_set_abs_params(input,
 				     encoder->axis, 0, encoder->steps, 0, 1);
 
-- 
2.17.1

[PATCH V2 2/2] Input: rotaty-encoder - Add DT binding document

[Donghoon Han]

Add DT binding document for rotary-encoder, keycode options.

Signed-off-by: Donghoon Han <nazgul33@gmail.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Daniel Mack <daniel@caiaq.de>
Cc: devicetree@vger.kernel.org
To: linux-input@vger.kernel.org
---
 .../devicetree/bindings/input/rotary-encoder.txt     | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/Documentation/devicetree/bindings/input/rotary-encoder.txt b/Documentation/devicetree/bindings/input/rotary-encoder.txt
index f99fe5cdeaec..9986ec2af2d4 100644
--- a/Documentation/devicetree/bindings/input/rotary-encoder.txt
+++ b/Documentation/devicetree/bindings/input/rotary-encoder.txt
@@ -12,6 +12,10 @@ Optional properties:
 - rotary-encoder,relative-axis: register a relative axis rather than an
   absolute one. Relative axis will only generate +1/-1 events on the input
   device, hence no steps need to be passed.
+- rotary-encoder,relative-keys : generate pair of key events. This setting
+  behaves just like relative-axis, generating key events instead.
+  (Keycodes[2] corresponds to -1/1 events.)
+- rotary-encoder,relative-keycodes : keycodes for relative-keys
 - rotary-encoder,rollover: Automatic rollover when the rotary value becomes
   greater than the specified steps or smaller than 0. For absolute axis only.
 - rotary-encoder,steps-per-period: Number of steps (stable states) per period.
@@ -48,3 +52,11 @@ Example:
 			rotary-encoder,encoding = "binary";
 			rotary-encoder,rollover;
 		};
+
+		rotary@2 {
+			compatible = "rotary-encoder";
+			gpios = <&gpio 21 0>, <&gpio 22 0>;
+			rotary-encoder,relative-keys;
+			rotary-encoder,relative-keycode = <103>, <108>;
+			rotary-encoder,steps-per-period = <2>;
+		};
-- 
2.17.1

Re: [PATCH V2 2/2] Input: rotaty-encoder - Add DT binding document

[Rob Herring]

On Mon, Jan 7, 2019 at 10:43 AM Donghoon Han <nazgul33@gmail.com> wrote:
>

The subject needs to be improved. It doesn't match the change.

> Add DT binding document for rotary-encoder, keycode options.
>
> Signed-off-by: Donghoon Han <nazgul33@gmail.com>
> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> Cc: Daniel Mack <daniel@caiaq.de>
> Cc: devicetree@vger.kernel.org
> To: linux-input@vger.kernel.org
> ---
>  .../devicetree/bindings/input/rotary-encoder.txt     | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/input/rotary-encoder.txt b/Documentation/devicetree/bindings/input/rotary-encoder.txt
> index f99fe5cdeaec..9986ec2af2d4 100644
> --- a/Documentation/devicetree/bindings/input/rotary-encoder.txt
> +++ b/Documentation/devicetree/bindings/input/rotary-encoder.txt
> @@ -12,6 +12,10 @@ Optional properties:
>  - rotary-encoder,relative-axis: register a relative axis rather than an
>    absolute one. Relative axis will only generate +1/-1 events on the input
>    device, hence no steps need to be passed.
> +- rotary-encoder,relative-keys : generate pair of key events. This setting
> +  behaves just like relative-axis, generating key events instead.
> +  (Keycodes[2] corresponds to -1/1 events.)
> +- rotary-encoder,relative-keycodes : keycodes for relative-keys
>  - rotary-encoder,rollover: Automatic rollover when the rotary value becomes
>    greater than the specified steps or smaller than 0. For absolute axis only.
>  - rotary-encoder,steps-per-period: Number of steps (stable states) per period.
> @@ -48,3 +52,11 @@ Example:
>                         rotary-encoder,encoding = "binary";
>                         rotary-encoder,rollover;
>                 };
> +
> +               rotary@2 {
> +                       compatible = "rotary-encoder";
> +                       gpios = <&gpio 21 0>, <&gpio 22 0>;
> +                       rotary-encoder,relative-keys;
> +                       rotary-encoder,relative-keycode = <103>, <108>;
> +                       rotary-encoder,steps-per-period = <2>;
> +               };
> --
> 2.17.1
>

Re: [PATCH V2 2/2] Input: rotaty-encoder - Add DT binding document

[Dmitry Torokhov]

On Tue, Jan 08, 2019 at 01:42:49AM +0900, Donghoon Han wrote:
> Add DT binding document for rotary-encoder, keycode options.
> 
> Signed-off-by: Donghoon Han <nazgul33@gmail.com>
> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> Cc: Daniel Mack <daniel@caiaq.de>
> Cc: devicetree@vger.kernel.org
> To: linux-input@vger.kernel.org
> ---
>  .../devicetree/bindings/input/rotary-encoder.txt     | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/input/rotary-encoder.txt b/Documentation/devicetree/bindings/input/rotary-encoder.txt
> index f99fe5cdeaec..9986ec2af2d4 100644
> --- a/Documentation/devicetree/bindings/input/rotary-encoder.txt
> +++ b/Documentation/devicetree/bindings/input/rotary-encoder.txt
> @@ -12,6 +12,10 @@ Optional properties:
>  - rotary-encoder,relative-axis: register a relative axis rather than an
>    absolute one. Relative axis will only generate +1/-1 events on the input
>    device, hence no steps need to be passed.
> +- rotary-encoder,relative-keys : generate pair of key events. This setting
> +  behaves just like relative-axis, generating key events instead.
> +  (Keycodes[2] corresponds to -1/1 events.)
> +- rotary-encoder,relative-keycodes : keycodes for relative-keys

Given that keycodes are linux-specific, I think the property should be
linux,keycodes. Also, I am not sure we need separate
rotary-encoder,relative-keys property as we can infer that we want to
generate keys from presence of linux,keycodes property.

Rob, any comments?

>  - rotary-encoder,rollover: Automatic rollover when the rotary value becomes
>    greater than the specified steps or smaller than 0. For absolute axis only.
>  - rotary-encoder,steps-per-period: Number of steps (stable states) per period.
> @@ -48,3 +52,11 @@ Example:
>  			rotary-encoder,encoding = "binary";
>  			rotary-encoder,rollover;
>  		};
> +
> +		rotary@2 {
> +			compatible = "rotary-encoder";
> +			gpios = <&gpio 21 0>, <&gpio 22 0>;
> +			rotary-encoder,relative-keys;
> +			rotary-encoder,relative-keycode = <103>, <108>;
> +			rotary-encoder,steps-per-period = <2>;
> +		};
> -- 
> 2.17.1
> 

Thanks.

-- 
Dmitry

Re: [PATCH V2 2/2] Input: rotaty-encoder - Add DT binding document

[Rob Herring]

On Mon, Jan 14, 2019 at 07:52:21PM -0800, Dmitry Torokhov wrote:
> On Tue, Jan 08, 2019 at 01:42:49AM +0900, Donghoon Han wrote:
> > Add DT binding document for rotary-encoder, keycode options.
> > 
> > Signed-off-by: Donghoon Han <nazgul33@gmail.com>
> > Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> > Cc: Daniel Mack <daniel@caiaq.de>
> > Cc: devicetree@vger.kernel.org
> > To: linux-input@vger.kernel.org
> > ---
> >  .../devicetree/bindings/input/rotary-encoder.txt     | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/input/rotary-encoder.txt b/Documentation/devicetree/bindings/input/rotary-encoder.txt
> > index f99fe5cdeaec..9986ec2af2d4 100644
> > --- a/Documentation/devicetree/bindings/input/rotary-encoder.txt
> > +++ b/Documentation/devicetree/bindings/input/rotary-encoder.txt
> > @@ -12,6 +12,10 @@ Optional properties:
> >  - rotary-encoder,relative-axis: register a relative axis rather than an
> >    absolute one. Relative axis will only generate +1/-1 events on the input
> >    device, hence no steps need to be passed.
> > +- rotary-encoder,relative-keys : generate pair of key events. This setting
> > +  behaves just like relative-axis, generating key events instead.
> > +  (Keycodes[2] corresponds to -1/1 events.)
> > +- rotary-encoder,relative-keycodes : keycodes for relative-keys
> 
> Given that keycodes are linux-specific, I think the property should be
> linux,keycodes. Also, I am not sure we need separate
> rotary-encoder,relative-keys property as we can infer that we want to
> generate keys from presence of linux,keycodes property.
> 
> Rob, any comments?

Yes, I had similar thoughts.

Re: Re: [PATCH V2 2/2] Input: rotaty-encoder - Add DT binding document

[Alexey Slepov]

Hello,

i used this rotary-encoder patch in my embedded project and found two 
errors:


First, in drivers/input/misc/rotary_encoder.c,
at @@ -237,6 +244,16 @@:
instead of

+        if (err)
+            dev_err(dev, "unable to get keycodes: %d\n", err);
+        return err;

it must be

+        if (err) {
+            dev_err(dev, "unable to get keycodes: %d\n", err);
+            return err;
+        }

otherwise successful creation of device is not possible.


Second, a typo in 
Documentation/devicetree/bindings/input/rotary-encoder.txt,
at @@ -48,3 +52,11 @@:
instead of

+            rotary-encoder,relative-keycode = <103>, <108>;

it should be

+            rotary-encoder,relative-keycodes = <103>, <108>;

otherwise keycodes are not found.


I am sorry, I know that E-Mail style is not good.
I have no time right now, but I'll be back in two weeks.
Someone, maybe Mr. Han, could submit a new version of the patch.
If not, I'll try to do it on my return. (it could take some time, since 
I am new to patchwork)

Best Regards and thanks
Alexey Slepov

Re: [PATCH V2 2/2] Input: rotaty-encoder - Add DT binding document

[Dmitry Torokhov]

[ resending to Rob... ]
On Tue, Jan 08, 2019 at 01:42:49AM +0900, Donghoon Han wrote:
> Add DT binding document for rotary-encoder, keycode options.
> 
> Signed-off-by: Donghoon Han <nazgul33@gmail.com>
> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> Cc: Daniel Mack <daniel@caiaq.de>
> Cc: devicetree@vger.kernel.org
> To: linux-input@vger.kernel.org
> ---
>  .../devicetree/bindings/input/rotary-encoder.txt     | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/input/rotary-encoder.txt b/Documentation/devicetree/bindings/input/rotary-encoder.txt
> index f99fe5cdeaec..9986ec2af2d4 100644
> --- a/Documentation/devicetree/bindings/input/rotary-encoder.txt
> +++ b/Documentation/devicetree/bindings/input/rotary-encoder.txt
> @@ -12,6 +12,10 @@ Optional properties:
>  - rotary-encoder,relative-axis: register a relative axis rather than an
>    absolute one. Relative axis will only generate +1/-1 events on the input
>    device, hence no steps need to be passed.
> +- rotary-encoder,relative-keys : generate pair of key events. This setting
> +  behaves just like relative-axis, generating key events instead.
> +  (Keycodes[2] corresponds to -1/1 events.)
> +- rotary-encoder,relative-keycodes : keycodes for relative-keys

Given that keycodes are linux-specific, I think the property should be
linux,keycodes. Also, I am not sure we need separate
rotary-encoder,relative-keys property as we can infer that we want to
generate keys from presence of linux,keycodes property.

Rob, any comments?

>  - rotary-encoder,rollover: Automatic rollover when the rotary value becomes
>    greater than the specified steps or smaller than 0. For absolute axis only.
>  - rotary-encoder,steps-per-period: Number of steps (stable states) per period.
> @@ -48,3 +52,11 @@ Example:
>  			rotary-encoder,encoding = "binary";
>  			rotary-encoder,rollover;
>  		};
> +
> +		rotary@2 {
> +			compatible = "rotary-encoder";
> +			gpios = <&gpio 21 0>, <&gpio 22 0>;
> +			rotary-encoder,relative-keys;
> +			rotary-encoder,relative-keycode = <103>, <108>;
> +			rotary-encoder,steps-per-period = <2>;
> +		};
> -- 
> 2.17.1
> 

Thanks.

-- 
Dmitry