[PATCH v3 2/3] Input: adc-joystick - Add polled input device support

Chris Morgan
2022-06-13T20:35:03Z

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 | 52 +++++++++++++++++++++------
1 file changed, 41 insertions(+), 11 deletions(-)

diff --git a/drivers/input/joystick/adc-joystick.c b/drivers/input/joystick/adc-joystick.c
index 78ebca7d400a..dc01cd0214d2 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 (device_property_read_bool(dev, "adc-joystick,no-hardware-trigger"))
+ joy->polled = 1;
+
+ 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) {
+ 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;
--
2.25.1