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jeplerjepler
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Make keypad select/poll'able for better async
This allows a small wrapper class to be written ```py class AsyncEventQueue: def __init__(self, events): self._events = events async def __await__(self): yield asyncio.core._io_queue.queue_read(self._events) return self._events.get() def __enter__(self): return self def __exit__(self, exc_type, exc_value, traceback): pass ``` and used to just "await" the next event: ```py async def key_task(): print("waiting for keypresses") with keypad.KeyMatrix([board.D4], [board.D5]) as keys, AsyncEventQueue(keys.events) as ev: while True: print(await ev) ``` Because checking the empty status of the EventQueue does not enter CircuitPython bytecode, it's assumed (but not measured) that this is more efficient than an equivalent loop with an `await async.sleep(0)` yield and introduces less latency than any non-zero sleep value.
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‎shared-bindings/keypad/EventQueue.c‎

Lines changed: 32 additions & 0 deletions
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@@ -24,8 +24,11 @@
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* THE SOFTWARE.
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*/
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#include "py/ioctl.h"
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#include "py/mperrno.h"
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#include "py/objproperty.h"
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#include "py/runtime.h"
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#include "py/stream.h"
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#include "shared-bindings/keypad/Event.h"
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#include "shared-bindings/keypad/EventQueue.h"
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@@ -141,12 +144,41 @@ STATIC const mp_rom_map_elem_t keypad_eventqueue_locals_dict_table[] = {
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STATIC MP_DEFINE_CONST_DICT(keypad_eventqueue_locals_dict, keypad_eventqueue_locals_dict_table);
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#if MICROPY_PY_USELECT
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STATIC mp_uint_t eventqueue_ioctl(mp_obj_t self_in, mp_uint_t request, uintptr_t arg, int *errcode) {
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(void)errcode;
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keypad_eventqueue_obj_t *self = MP_OBJ_TO_PTR(self_in);
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switch (request) {
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case MP_STREAM_POLL: {
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mp_uint_t flags = arg;
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mp_uint_t ret = 0;
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if ((flags & MP_IOCTL_POLL_RD) && common_hal_keypad_eventqueue_get_length(self)) {
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ret |= MP_IOCTL_POLL_RD;
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}
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return ret;
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}
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default:
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*errcode = MP_EINVAL;
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return MP_STREAM_ERROR;
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}
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}
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STATIC const mp_stream_p_t eventqueue_p = {
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MP_PROTO_IMPLEMENT(MP_QSTR_protocol_stream)
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.ioctl = eventqueue_ioctl,
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};
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#endif
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const mp_obj_type_t keypad_eventqueue_type = {
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{ &mp_type_type },
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.flags = MP_TYPE_FLAG_EXTENDED,
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.name = MP_QSTR_EventQueue,
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MP_TYPE_EXTENDED_FIELDS(
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.unary_op = keypad_eventqueue_unary_op,
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#if MICROPY_PY_USELECT
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.protocol = &eventqueue_p,
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#endif
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),
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.locals_dict = (mp_obj_t)&keypad_eventqueue_locals_dict,
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};

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