From: Srinivas Pandruvada Date: Fri, 20 Feb 2026 22:45:14 +0000 (-0800) Subject: iio: hid-sensors: Use software trigger X-Git-Tag: v7.0-rc7~8^2~25^2~10 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c47ac75f5f24020cc0c8b835457a7637ad450939;p=thirdparty%2Fkernel%2Flinux.git iio: hid-sensors: Use software trigger Recent changes linux mainline resulted in warning: "genirq: Warn about using IRQF_ONESHOT without a threaded handler" when HID sensor hub is used. When INDIO_BUFFER_TRIGGERED is used, the core attaches a poll function when enabling the buffer. This poll function uses request_threaded_irq() with both bottom half and top half handlers. But when using HID sensor hub, bottom half (thread handler) is not registered. In HID sensors, once a sensor is powered on, the hub collects samples and pushes data to the host when programmed thresholds are met. When this data is received for a sensor, it is pushed using iio_push_to_buffers_with_ts(). The sensor is powered ON or OFF based on the trigger callback set_trigger_state() when the poll function is attached. During the call to iio_triggered_buffer_setup_ext(), the HID sensor specifies only a handler function but provides no thread handler, as there is no data to read from the hub in thread context. Internally, this results in calling request_threaded_irq(). Recent kernel changes now warn when request_threaded_irq() is called without a thread handler. To address this issue, fundamental changes are required to avoid using iio_triggered_buffer_setup_ext(). HID sensors can use INDIO_BUFFER_SOFTWARE instead of INDIO_BUFFER_TRIGGERED, as this can work in trigger-less mode. In this approach, when user space opens the buffer, the sensor is powered on, and when the buffer is closed, the sensor is powered off using iio_buffer_setup_ops callbacks. Signed-off-by: Srinivas Pandruvada Signed-off-by: Jonathan Cameron --- diff --git a/drivers/iio/common/hid-sensors/hid-sensor-trigger.c b/drivers/iio/common/hid-sensors/hid-sensor-trigger.c index 5540e2d28f4ac..417c4ab8c1b27 100644 --- a/drivers/iio/common/hid-sensors/hid-sensor-trigger.c +++ b/drivers/iio/common/hid-sensors/hid-sensor-trigger.c @@ -14,6 +14,7 @@ #include #include #include +#include #include "hid-sensor-trigger.h" static ssize_t _hid_sensor_set_report_latency(struct device *dev, @@ -202,12 +203,21 @@ static void hid_sensor_set_power_work(struct work_struct *work) _hid_sensor_power_state(attrb, true); } -static int hid_sensor_data_rdy_trigger_set_state(struct iio_trigger *trig, - bool state) +static int buffer_postenable(struct iio_dev *indio_dev) { - return hid_sensor_power_state(iio_trigger_get_drvdata(trig), state); + return hid_sensor_power_state(iio_device_get_drvdata(indio_dev), 1); } +static int buffer_predisable(struct iio_dev *indio_dev) +{ + return hid_sensor_power_state(iio_device_get_drvdata(indio_dev), 0); +} + +static const struct iio_buffer_setup_ops hid_sensor_buffer_ops = { + .postenable = buffer_postenable, + .predisable = buffer_predisable, +}; + void hid_sensor_remove_trigger(struct iio_dev *indio_dev, struct hid_sensor_common *attrb) { @@ -219,14 +229,9 @@ void hid_sensor_remove_trigger(struct iio_dev *indio_dev, cancel_work_sync(&attrb->work); iio_trigger_unregister(attrb->trigger); iio_trigger_free(attrb->trigger); - iio_triggered_buffer_cleanup(indio_dev); } EXPORT_SYMBOL_NS(hid_sensor_remove_trigger, "IIO_HID"); -static const struct iio_trigger_ops hid_sensor_trigger_ops = { - .set_trigger_state = &hid_sensor_data_rdy_trigger_set_state, -}; - int hid_sensor_setup_trigger(struct iio_dev *indio_dev, const char *name, struct hid_sensor_common *attrb) { @@ -239,25 +244,34 @@ int hid_sensor_setup_trigger(struct iio_dev *indio_dev, const char *name, else fifo_attrs = NULL; - ret = iio_triggered_buffer_setup_ext(indio_dev, - &iio_pollfunc_store_time, NULL, - IIO_BUFFER_DIRECTION_IN, - NULL, fifo_attrs); + indio_dev->modes = INDIO_DIRECT_MODE | INDIO_HARDWARE_TRIGGERED; + + ret = devm_iio_kfifo_buffer_setup_ext(&indio_dev->dev, indio_dev, + &hid_sensor_buffer_ops, + fifo_attrs); if (ret) { - dev_err(&indio_dev->dev, "Triggered Buffer Setup Failed\n"); + dev_err(&indio_dev->dev, "Kfifo Buffer Setup Failed\n"); return ret; } + /* + * The current user space in distro "iio-sensor-proxy" is not working in + * trigerless mode and it expects + * /sys/bus/iio/devices/iio:device0/trigger/current_trigger. + * The change replacing iio_triggered_buffer_setup_ext() with + * devm_iio_kfifo_buffer_setup_ext() will not create attribute without + * registering a trigger with INDIO_HARDWARE_TRIGGERED. + * So the below code fragment is still required. + */ + trig = iio_trigger_alloc(indio_dev->dev.parent, "%s-dev%d", name, iio_device_id(indio_dev)); if (trig == NULL) { dev_err(&indio_dev->dev, "Trigger Allocate Failed\n"); - ret = -ENOMEM; - goto error_triggered_buffer_cleanup; + return -ENOMEM; } iio_trigger_set_drvdata(trig, attrb); - trig->ops = &hid_sensor_trigger_ops; ret = iio_trigger_register(trig); if (ret) { @@ -284,8 +298,6 @@ error_unreg_trigger: iio_trigger_unregister(trig); error_free_trig: iio_trigger_free(trig); -error_triggered_buffer_cleanup: - iio_triggered_buffer_cleanup(indio_dev); return ret; } EXPORT_SYMBOL_NS(hid_sensor_setup_trigger, "IIO_HID");