s64 iio_get_time_ns(const struct iio_dev *indio_dev);
unsigned int iio_get_time_res(const struct iio_dev *indio_dev);
-/* Device operating modes */
+/*
+ * Device operating modes
+ * @INDIO_DIRECT_MODE: There is an access to either:
+ * a) The last single value available for devices that do not provide
+ * on-demand reads.
+ * b) A new value after performing an on-demand read otherwise.
+ * On most devices, this is a single-shot read. On some devices with data
+ * streams without an 'on-demand' function, this might also be the 'last value'
+ * feature. Above all, this mode internally means that we are not in any of the
+ * other modes, and sysfs reads should work.
+ * Device drivers should inform the core if they support this mode.
+ * @INDIO_BUFFER_TRIGGERED: Common mode when dealing with kfifo buffers.
+ * It indicates that an explicit trigger is required. This requests the core to
+ * attach a poll function when enabling the buffer, which is indicated by the
+ * _TRIGGERED suffix.
+ * The core will ensure this mode is set when registering a triggered buffer
+ * with iio_triggered_buffer_setup().
+ * @INDIO_BUFFER_SOFTWARE: Another kfifo buffer mode, but not event triggered.
+ * No poll function can be attached because there is no triggered infrastructure
+ * we can use to cause capture. There is a kfifo that the driver will fill, but
+ * not "only one scan at a time". Typically, hardware will have a buffer that
+ * can hold multiple scans. Software may read one or more scans at a single time
+ * and push the available data to a Kfifo. This means the core will not attach
+ * any poll function when enabling the buffer.
+ * The core will ensure this mode is set when registering a simple kfifo buffer
+ * with devm_iio_kfifo_buffer_setup().
+ * @INDIO_BUFFER_HARDWARE: For specific hardware, if unsure do not use this mode.
+ * Same as above but this time the buffer is not a kfifo where we have direct
+ * access to the data. Instead, the consumer driver must access the data through
+ * non software visible channels (or DMA when there is no demux possible in
+ * software)
+ * The core will ensure this mode is set when registering a dmaengine buffer
+ * with devm_iio_dmaengine_buffer_setup().
+ * @INDIO_EVENT_TRIGGERED: Very unusual mode.
+ * Triggers usually refer to an external event which will start data capture.
+ * Here it is kind of the opposite as, a particular state of the data might
+ * produce an event which can be considered as an event. We don't necessarily
+ * have access to the data itself, but to the event produced. For example, this
+ * can be a threshold detector. The internal path of this mode is very close to
+ * the INDIO_BUFFER_TRIGGERED mode.
+ * The core will ensure this mode is set when registering a triggered event.
+ * @INDIO_HARDWARE_TRIGGERED: Very unusual mode.
+ * Here, triggers can result in data capture and can be routed to multiple
+ * hardware components, which make them close to regular triggers in the way
+ * they must be managed by the core, but without the entire interrupts/poll
+ * functions burden. Interrupts are irrelevant as the data flow is hardware
+ * mediated and distributed.
+ */
#define INDIO_DIRECT_MODE 0x01
#define INDIO_BUFFER_TRIGGERED 0x02
#define INDIO_BUFFER_SOFTWARE 0x04