[PATCH v5 0/3] adc-joystick: Add polled support

[PATCH v5 0/3] adc-joystick: Add polled support

[Chris Morgan]

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>.

Changes from V4:
 - Added unit property to devicetree attribute making it now
   "poll-interval-ms".
 - Simplified logic for setting polled value and made variable names
   more clear.

Changes from V3:
 - After lengthy discussion decided to support with existing attribute
   of "poll-interval". If present, the driver will use polling and if
   not present, it will use triggered buffers (as the driver does
   today).
 - Corrected some lines to honor the 80 character line-limit.
 - Check return value from polling method and return early if there
   is an error reading the data.

Changes from V2:
 - Changed parameter from "adc-joystick,polled" to
   "adc-joystick,no-hardware-trigger" as it is more representative of
   what the driver and hardware are doing.

Changes from V1:
 - Removed driver compatible string of "adc-joystick-polled".
 - Added new optional boolean value of "adc-joystick,polled".
 - Cleaned up if statements regarding polling behavior.

Chris Morgan (3):
  dt-bindings: adc-joystick: add poll-interval-ms
  Input: adc-joystick - Add polled input device support
  arm64: dts: rockchip: Update joystick to polled for OG2

 .../bindings/input/adc-joystick.yaml          |  6 +++
 .../boot/dts/rockchip/rk3326-odroid-go2.dts   |  1 +
 drivers/input/joystick/adc-joystick.c         | 51 +++++++++++++++----
 3 files changed, 47 insertions(+), 11 deletions(-)

-- 
2.34.1

[PATCH v5 1/3] dt-bindings: adc-joystick: add poll-interval-ms

[Chris Morgan]

New devicetree attribute of "poll-interval-ms".

Add poll-interval support for the adc-joystick documentation. This is
an optional value and if not provided the adc-joystick works as it
does today (with triggered buffers). If this value is provided, the
adc-joystick driver is polled at the specified interval. A new
attribute was added instead of using the existing attribute of
"poll-interval" to comply with rules detailed in property-units.yaml.

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

diff --git a/Documentation/devicetree/bindings/input/adc-joystick.yaml b/Documentation/devicetree/bindings/input/adc-joystick.yaml
index 2ee04e03bc22..cfd8d1af5d2c 100644
--- a/Documentation/devicetree/bindings/input/adc-joystick.yaml
+++ b/Documentation/devicetree/bindings/input/adc-joystick.yaml
@@ -18,6 +18,12 @@ properties:
   compatible:
     const: adc-joystick
 
+  poll-interval-ms:
+    description:
+      Poll interval time in milliseconds. If not specified, device will use
+      iio buffer.
+    $ref: /schemas/types.yaml#/definitions/uint32
+
   io-channels:
     minItems: 1
     maxItems: 1024
-- 
2.34.1

[PATCH v5 2/3] Input: adc-joystick - Add polled input device support

[Chris Morgan]

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 | 51 +++++++++++++++++++++------
 1 file changed, 40 insertions(+), 11 deletions(-)

diff --git a/drivers/input/joystick/adc-joystick.c b/drivers/input/joystick/adc-joystick.c
index 78ebca7d400a..e52f8b2b5563 100644
--- a/drivers/input/joystick/adc-joystick.c
+++ b/drivers/input/joystick/adc-joystick.c
@@ -26,8 +26,23 @@ 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, ret;
+
+	for (i = 0; i < joy->num_chans; i++) {
+		ret = iio_read_channel_raw(&joy->chans[i], &val);
+		if (ret < 0)
+			return;
+		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;
@@ -179,6 +194,7 @@ static int adc_joystick_probe(struct platform_device *pdev)
 	int error;
 	int bits;
 	int i;
+	unsigned int poll_interval;
 
 	joy = devm_kzalloc(dev, sizeof(*joy), GFP_KERNEL);
 	if (!joy)
@@ -215,8 +231,17 @@ 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;
+
+	joy->polled = !device_property_read_u32(dev, "poll-interval-ms",
+						&poll_interval);
+
+	if (joy->polled) {
+		input_setup_polling(input, adc_joystick_poll);
+		input_set_poll_interval(input, poll_interval);
+	} else {
+		input->open = adc_joystick_open;
+		input->close = adc_joystick_close;
+	}
 
 	error = adc_joystick_set_axes(dev, joy);
 	if (error)
@@ -229,16 +254,20 @@ 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) {
+		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;
-- 
2.34.1

[PATCH v5 3/3] arm64: dts: rockchip: Update joystick to polled for OG2

[Chris Morgan]

Update the Odroid Go Advance to use "poll-interval-ms" 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 | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/boot/dts/rockchip/rk3326-odroid-go2.dts b/arch/arm64/boot/dts/rockchip/rk3326-odroid-go2.dts
index ea0695b51ecd..5a4f81861e07 100644
--- a/arch/arm64/boot/dts/rockchip/rk3326-odroid-go2.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3326-odroid-go2.dts
@@ -26,6 +26,7 @@ adc-joystick {
 		compatible = "adc-joystick";
 		io-channels = <&saradc 1>,
 			      <&saradc 2>;
+		poll-interval-ms = <60>;
 		#address-cells = <1>;
 		#size-cells = <0>;
 
-- 
2.34.1

Re: [PATCH v5 1/3] dt-bindings: adc-joystick: add poll-interval-ms

[Rob Herring]

On Tue, 28 Jun 2022 14:14:58 -0500, Chris Morgan wrote:
> New devicetree attribute of "poll-interval-ms".
> 
> Add poll-interval support for the adc-joystick documentation. This is
> an optional value and if not provided the adc-joystick works as it
> does today (with triggered buffers). If this value is provided, the
> adc-joystick driver is polled at the specified interval. A new
> attribute was added instead of using the existing attribute of
> "poll-interval" to comply with rules detailed in property-units.yaml.
> 
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> ---
>  Documentation/devicetree/bindings/input/adc-joystick.yaml | 6 ++++++
>  1 file changed, 6 insertions(+)
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/input/adc-joystick.yaml: properties:poll-interval-ms: '$ref' should not be valid under {'const': '$ref'}
	hint: Standard unit suffix properties don't need a type $ref
	from schema $id: http://devicetree.org/meta-schemas/core.yaml#
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml: patternProperties:^thermistor@:properties:adi,excitation-current-nanoamp: '$ref' should not be valid under {'const': '$ref'}
	hint: Standard unit suffix properties don't need a type $ref
	from schema $id: http://devicetree.org/meta-schemas/core.yaml#
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/input/adc-joystick.yaml: ignoring, error in schema: properties: poll-interval-ms
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.yaml: ignoring, error in schema: patternProperties: ^thermistor@: properties: adi,excitation-current-nanoamp
Documentation/devicetree/bindings/input/adc-joystick.example.dtb:0:0: /example-0/adc-joystick: failed to match any schema with compatible: ['adc-joystick']
Documentation/devicetree/bindings/iio/temperature/adi,ltc2983.example.dtb:0:0: /example-0/spi/ltc2983@0: failed to match any schema with compatible: ['adi,ltc2983']

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/patch/

This check can fail if there are any dependencies. The base for a patch
series is generally the most recent rc1.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit.