On 2022-07-21 18:46, Chris Morgan wrote:
From: Chris Morgan <macromorgan@xxxxxxxxxxx>
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@xxxxxxxxx>
Signed-off-by: Chris Morgan <macromorgan@xxxxxxxxxxx>
---
Hey Chris,
sorry for the late response. Comments in-line.
Cheers,
Artur
drivers/input/joystick/adc-joystick.c | 82 ++++++++++++++++++++-------
1 file changed, 62 insertions(+), 20 deletions(-)
diff --git a/drivers/input/joystick/adc-joystick.c
b/drivers/input/joystick/adc-joystick.c
index 78ebca7d400a..085b8e10dfb5 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;
@@ -178,7 +193,9 @@ static int adc_joystick_probe(struct
platform_device *pdev)
struct input_dev *input;
int error;
int bits;
+ int chan_storage;
int i;
+ unsigned int poll_interval;
joy = devm_kzalloc(dev, sizeof(*joy), GFP_KERNEL);
if (!joy)
@@ -192,16 +209,31 @@ static int adc_joystick_probe(struct
platform_device *pdev)
return error;
}
- /* Count how many channels we got. NULL terminated. */
+ if (device_property_present(dev, "poll-interval")) {
+ error = device_property_read_u32(dev, "poll-interval",
+ &poll_interval);
+ if (error)
+ return error;
+ joy->polled = true;
+ }
+
+ /* Count how many channels we got. NULL terminated. Do not check the
+ * storage size if using polling.
+ */
As per Linux coding style, the multi-line comment opens with a lone `/*`
line. Also, move the second sentence into a new line for readability.
+ chan_storage = joy->chans[0].channel->scan_type.storagebits;
for (i = 0; joy->chans[i].indio_dev; i++) {
- bits = joy->chans[i].channel->scan_type.storagebits;
- if (!bits || bits > 16) {
- dev_err(dev, "Unsupported channel storage size\n");
- return -EINVAL;
- }
- if (bits != joy->chans[0].channel->scan_type.storagebits) {
- dev_err(dev, "Channels must have equal storage size\n");
- return -EINVAL;
+ if (!joy->polled) {
+ bits = joy->chans[i].channel->scan_type.storagebits;
+ if (!bits || bits > 16) {
+ dev_err(dev,
+ "Unsupported channel storage size\n");
+ return -EINVAL;
+ }
+ if (bits != chan_storage) {
+ dev_err(dev,
+ "Channels must be equal size\n");
+ return -EINVAL;
+ }
Just do `for (i = 0; !joy->polled && joy->chans[i].indio_dev; i++)`, as
this will terminate early if we're polling.
Then we'll also be able to restore the loop body to its original code
and
get rid of that `chan_storage` helper.
}
}
joy->num_chans = i;
@@ -215,8 +247,14 @@ 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 (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 +267,20 @@ 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;
