[PATCH 0/3] adc-joystick: Add polled support

[PATCH 0/3] adc-joystick: Add polled support

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Add support to the existing adc-joystick driver to support polling
rather than relying on triggered buffers. This is useful for devices
that do not offer triggered buffers in hardware. Code adapted from
changes made by Maya Matuszczyk <maccraft123mc@gmail.com>.

Chris Morgan (3):
  dt-bindings: adc-joystick: bindings for adc-joystick-polled
  Input: adc-joystick - Add polled input device support
  arm64: dts: rockchip: Update joystick to polled for Odroid-Go2

 .../bindings/input/adc-joystick.yaml          |  8 ++-
 .../boot/dts/rockchip/rk3326-odroid-go2.dts   |  2 +-
 drivers/input/joystick/adc-joystick.c         | 53 +++++++++++++++----
 3 files changed, 49 insertions(+), 14 deletions(-)

-- 
2.25.1

[PATCH 1/3] dt-bindings: adc-joystick: bindings for adc-joystick-polled

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Add devicetree bindings for adc-joystick-polled.

Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
---
 Documentation/devicetree/bindings/input/adc-joystick.yaml | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/input/adc-joystick.yaml b/Documentation/devicetree/bindings/input/adc-joystick.yaml
index 2ee04e03bc22..a9d2ac157322 100644
--- a/Documentation/devicetree/bindings/input/adc-joystick.yaml
+++ b/Documentation/devicetree/bindings/input/adc-joystick.yaml
@@ -12,11 +12,15 @@ maintainers:
 
 description: >
   Bindings for joystick devices connected to ADC controllers supporting
-  the Industrial I/O subsystem.
+  the Industrial I/O subsystem. Supports both polled devices where no
+  iio trigger is available and non-polled devices which are triggered
+  by iio.
 
 properties:
   compatible:
-    const: adc-joystick
+    enum:
+      - adc-joystick
+      - adc-joystick-polled
 
   io-channels:
     minItems: 1
-- 
2.25.1

[PATCH 2/3] Input: adc-joystick - Add polled input device support

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Add polled input device support to the adc-joystick driver. This is
useful for devices which do not have hardware capable triggers on
their SARADC. Code modified from adc-joystick.c changes made by Maya
Matuszczyk.

Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
---
 drivers/input/joystick/adc-joystick.c | 53 +++++++++++++++++++++------
 1 file changed, 42 insertions(+), 11 deletions(-)

diff --git a/drivers/input/joystick/adc-joystick.c b/drivers/input/joystick/adc-joystick.c
index 78ebca7d400a..83a5a420141e 100644
--- a/drivers/input/joystick/adc-joystick.c
+++ b/drivers/input/joystick/adc-joystick.c
@@ -13,6 +13,10 @@
 
 #include <asm/unaligned.h>
 
+#define ADC_JSK_POLL_INTERVAL	16
+#define ADC_JSK_POLL_MIN	8
+#define ADC_JSK_POLL_MAX	32
+
 struct adc_joystick_axis {
 	u32 code;
 	s32 range[2];
@@ -26,8 +30,21 @@ struct adc_joystick {
 	struct adc_joystick_axis *axes;
 	struct iio_channel *chans;
 	int num_chans;
+	bool polled;
 };
 
+static void adc_joystick_poll(struct input_dev *input)
+{
+	struct adc_joystick *joy = input_get_drvdata(input);
+	int i, val;
+
+	for (i = 0; i < joy->num_chans; i++) {
+		iio_read_channel_raw(&joy->chans[i], &val);
+		input_report_abs(input, joy->axes[i].code, val);
+	}
+	input_sync(input);
+}
+
 static int adc_joystick_handle(const void *data, void *private)
 {
 	struct adc_joystick *joy = private;
@@ -215,8 +232,19 @@ static int adc_joystick_probe(struct platform_device *pdev)
 	joy->input = input;
 	input->name = pdev->name;
 	input->id.bustype = BUS_HOST;
-	input->open = adc_joystick_open;
-	input->close = adc_joystick_close;
+
+	if (of_device_is_compatible(dev->of_node, "adc-joystick-polled"))
+		joy->polled = 1;
+
+	if (joy->polled == 1) {
+		input_setup_polling(input, adc_joystick_poll);
+		input_set_poll_interval(input, ADC_JSK_POLL_INTERVAL);
+		input_set_min_poll_interval(input, ADC_JSK_POLL_MIN);
+		input_set_max_poll_interval(input, ADC_JSK_POLL_MAX);
+	} else {
+		input->open = adc_joystick_open;
+		input->close = adc_joystick_close;
+	}
 
 	error = adc_joystick_set_axes(dev, joy);
 	if (error)
@@ -229,16 +257,18 @@ static int adc_joystick_probe(struct platform_device *pdev)
 		return error;
 	}
 
-	joy->buffer = iio_channel_get_all_cb(dev, adc_joystick_handle, joy);
-	if (IS_ERR(joy->buffer)) {
-		dev_err(dev, "Unable to allocate callback buffer\n");
-		return PTR_ERR(joy->buffer);
-	}
+	if (joy->polled == 0) {
+		joy->buffer = iio_channel_get_all_cb(dev, adc_joystick_handle, joy);
+		if (IS_ERR(joy->buffer)) {
+			dev_err(dev, "Unable to allocate callback buffer\n");
+			return PTR_ERR(joy->buffer);
+		}
 
-	error = devm_add_action_or_reset(dev, adc_joystick_cleanup, joy->buffer);
-	if (error)  {
-		dev_err(dev, "Unable to add action\n");
-		return error;
+		error = devm_add_action_or_reset(dev, adc_joystick_cleanup, joy->buffer);
+		if (error)  {
+			dev_err(dev, "Unable to add action\n");
+			return error;
+		}
 	}
 
 	return 0;
@@ -246,6 +276,7 @@ static int adc_joystick_probe(struct platform_device *pdev)
 
 static const struct of_device_id adc_joystick_of_match[] = {
 	{ .compatible = "adc-joystick", },
+	{ .compatible = "adc-joystick-polled", },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, adc_joystick_of_match);
-- 
2.25.1

[PATCH 3/3] arm64: dts: rockchip: Update joystick to polled for Odroid-Go2

[Chris Morgan]

From: Chris Morgan <macromorgan@hotmail.com>

Update the Odroid Go Advance to use the polled method from the
adc-joystick driver.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
---
 arch/arm64/boot/dts/rockchip/rk3326-odroid-go2.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/rockchip/rk3326-odroid-go2.dts b/arch/arm64/boot/dts/rockchip/rk3326-odroid-go2.dts
index ea0695b51ecd..9766f80166f8 100644
--- a/arch/arm64/boot/dts/rockchip/rk3326-odroid-go2.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3326-odroid-go2.dts
@@ -23,7 +23,7 @@ chosen {
 	};
 
 	adc-joystick {
-		compatible = "adc-joystick";
+		compatible = "adc-joystick-polled";
 		io-channels = <&saradc 1>,
 			      <&saradc 2>;
 		#address-cells = <1>;
-- 
2.25.1

Re: [PATCH 1/3] dt-bindings: adc-joystick: bindings for adc-joystick-polled

[Artur Rojek]

On 2022-06-01 21:17, Chris Morgan wrote:
> From: Chris Morgan <macromorgan@hotmail.com>

Hi Chris,

> 
> Add devicetree bindings for adc-joystick-polled.
> 
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> ---
>  Documentation/devicetree/bindings/input/adc-joystick.yaml | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/input/adc-joystick.yaml
> b/Documentation/devicetree/bindings/input/adc-joystick.yaml
> index 2ee04e03bc22..a9d2ac157322 100644
> --- a/Documentation/devicetree/bindings/input/adc-joystick.yaml
> +++ b/Documentation/devicetree/bindings/input/adc-joystick.yaml
> @@ -12,11 +12,15 @@ maintainers:
> 
>  description: >
>    Bindings for joystick devices connected to ADC controllers 
> supporting
> -  the Industrial I/O subsystem.
> +  the Industrial I/O subsystem. Supports both polled devices where no
> +  iio trigger is available and non-polled devices which are triggered
> +  by iio.
> 
>  properties:
>    compatible:
> -    const: adc-joystick
> +    enum:
> +      - adc-joystick
> +      - adc-joystick-polled

There is no need to create a new compatible for your functionality. 
Instead, just add a new (optional) property.

cheers,
Artur

> 
>    io-channels:
>      minItems: 1

Re: [PATCH 2/3] Input: adc-joystick - Add polled input device support

[Artur Rojek]

On 2022-06-01 21:17, Chris Morgan wrote:
> From: Chris Morgan <macromorgan@hotmail.com>

Hi Chris,

Thanks for your patch. Here's some things I spotted on a quick glance. 
I'll test this patch against the existing (non-poll) devices over, or 
after the weekend.

> 
> Add polled input device support to the adc-joystick driver. This is
> useful for devices which do not have hardware capable triggers on
> their SARADC. Code modified from adc-joystick.c changes made by Maya
> Matuszczyk.
> 
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> ---
>  drivers/input/joystick/adc-joystick.c | 53 +++++++++++++++++++++------
>  1 file changed, 42 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/input/joystick/adc-joystick.c
> b/drivers/input/joystick/adc-joystick.c
> index 78ebca7d400a..83a5a420141e 100644
> --- a/drivers/input/joystick/adc-joystick.c
> +++ b/drivers/input/joystick/adc-joystick.c
> @@ -13,6 +13,10 @@
> 
>  #include <asm/unaligned.h>
> 
> +#define ADC_JSK_POLL_INTERVAL	16
> +#define ADC_JSK_POLL_MIN	8
> +#define ADC_JSK_POLL_MAX	32
> +
>  struct adc_joystick_axis {
>  	u32 code;
>  	s32 range[2];
> @@ -26,8 +30,21 @@ struct adc_joystick {
>  	struct adc_joystick_axis *axes;
>  	struct iio_channel *chans;
>  	int num_chans;
> +	bool polled;
>  };
> 
> +static void adc_joystick_poll(struct input_dev *input)
> +{
> +	struct adc_joystick *joy = input_get_drvdata(input);
> +	int i, val;
> +
> +	for (i = 0; i < joy->num_chans; i++) {
> +		iio_read_channel_raw(&joy->chans[i], &val);
> +		input_report_abs(input, joy->axes[i].code, val);
> +	}
> +	input_sync(input);
> +}
> +
>  static int adc_joystick_handle(const void *data, void *private)
>  {
>  	struct adc_joystick *joy = private;
> @@ -215,8 +232,19 @@ static int adc_joystick_probe(struct 
> platform_device *pdev)
>  	joy->input = input;
>  	input->name = pdev->name;
>  	input->id.bustype = BUS_HOST;
> -	input->open = adc_joystick_open;
> -	input->close = adc_joystick_close;
> +
> +	if (of_device_is_compatible(dev->of_node, "adc-joystick-polled"))
> +		joy->polled = 1;
Don't use a new compatible for that (see my comment for patch 1/3). Keep 
it as a property and then you can access it through 
`fwnode_property_read_bool`.

> +
> +	if (joy->polled == 1) {
It's a bool, so just do `if (joy->polled)`.

> +		input_setup_polling(input, adc_joystick_poll);
> +		input_set_poll_interval(input, ADC_JSK_POLL_INTERVAL);
> +		input_set_min_poll_interval(input, ADC_JSK_POLL_MIN);
> +		input_set_max_poll_interval(input, ADC_JSK_POLL_MAX);
> +	} else {
> +		input->open = adc_joystick_open;
> +		input->close = adc_joystick_close;
> +	}
> 
>  	error = adc_joystick_set_axes(dev, joy);
>  	if (error)
> @@ -229,16 +257,18 @@ static int adc_joystick_probe(struct
> platform_device *pdev)
>  		return error;
>  	}
> 
> -	joy->buffer = iio_channel_get_all_cb(dev, adc_joystick_handle, joy);
> -	if (IS_ERR(joy->buffer)) {
> -		dev_err(dev, "Unable to allocate callback buffer\n");
> -		return PTR_ERR(joy->buffer);
> -	}
> +	if (joy->polled == 0) {
Same here. Just do `if (!joy->polled)`.

Cheers,
Artur

> +		joy->buffer = iio_channel_get_all_cb(dev, adc_joystick_handle, joy);
> +		if (IS_ERR(joy->buffer)) {
> +			dev_err(dev, "Unable to allocate callback buffer\n");
> +			return PTR_ERR(joy->buffer);
> +		}
> 
> -	error = devm_add_action_or_reset(dev, adc_joystick_cleanup, 
> joy->buffer);
> -	if (error)  {
> -		dev_err(dev, "Unable to add action\n");
> -		return error;
> +		error = devm_add_action_or_reset(dev, adc_joystick_cleanup, 
> joy->buffer);
> +		if (error)  {
> +			dev_err(dev, "Unable to add action\n");
> +			return error;
> +		}
>  	}
> 
>  	return 0;
> @@ -246,6 +276,7 @@ static int adc_joystick_probe(struct 
> platform_device *pdev)
> 
>  static const struct of_device_id adc_joystick_of_match[] = {
>  	{ .compatible = "adc-joystick", },
> +	{ .compatible = "adc-joystick-polled", },
>  	{ }
>  };
>  MODULE_DEVICE_TABLE(of, adc_joystick_of_match);

Re: [PATCH 1/3] dt-bindings: adc-joystick: bindings for adc-joystick-polled

[Rob Herring]

On Wed, Jun 01, 2022 at 09:44:43PM +0200, Artur Rojek wrote:
> On 2022-06-01 21:17, Chris Morgan wrote:
> > From: Chris Morgan <macromorgan@hotmail.com>
> 
> Hi Chris,
> 
> > 
> > Add devicetree bindings for adc-joystick-polled.
> > 
> > Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> > Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> > ---
> >  Documentation/devicetree/bindings/input/adc-joystick.yaml | 8 ++++++--
> >  1 file changed, 6 insertions(+), 2 deletions(-)
> > 
> > diff --git a/Documentation/devicetree/bindings/input/adc-joystick.yaml
> > b/Documentation/devicetree/bindings/input/adc-joystick.yaml
> > index 2ee04e03bc22..a9d2ac157322 100644
> > --- a/Documentation/devicetree/bindings/input/adc-joystick.yaml
> > +++ b/Documentation/devicetree/bindings/input/adc-joystick.yaml
> > @@ -12,11 +12,15 @@ maintainers:
> > 
> >  description: >
> >    Bindings for joystick devices connected to ADC controllers supporting
> > -  the Industrial I/O subsystem.
> > +  the Industrial I/O subsystem. Supports both polled devices where no
> > +  iio trigger is available and non-polled devices which are triggered
> > +  by iio.
> > 
> >  properties:
> >    compatible:
> > -    const: adc-joystick
> > +    enum:
> > +      - adc-joystick
> > +      - adc-joystick-polled
> 
> There is no need to create a new compatible for your functionality. Instead,
> just add a new (optional) property.

Perhaps the already defined for input devices 'poll-interval'.

Rob