Re: [PATCH v2 2/3] Input: adc-joystick - Add polled input device support
From: Heiko Stübner <heiko@sntech.de>
Date: 2022-06-02 11:02:00
Also in:
linux-devicetree
Am Mittwoch, 1. Juni 2022, 22:49:26 CEST schrieb Chris Morgan:
From: Chris Morgan <redacted> 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.
as the dts patch mentiones the odroid go2, this probably means the Rockchip-saradc? I very much remember that we converted the saradc to also support triggered buffers [0] two years ago, and as I remember that worked rather nicely on the Go-1 at least - similar hardware I think. So it would be really helpful to provide some more explanation on why this isn't enough for your use-case. [0] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=4e130dc7b41348b13684f0758c26cc6cf72a3449
quoted hunk ↗ jump to hunk
Signed-off-by: Maya Matuszczyk <redacted> Signed-off-by: Chris Morgan <redacted> --- 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..5a28fe7b8ebc 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,polled")) + 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;