samd/machine_uart: Implement uart.txdone() and uart.flush().

Using the stream method for uart.flush().

uart.txdone() returns True, if the uart not busy, False otherwise.

uart.flush() waits until all bytes have been transmitted or a timeout
triggers.  The timeout is determined by the buffer size and the baud rate.

Also fix two inconsistencies when not using txbuf:
- Report in ioctl as being writeable if there is room in the tx buffer,
  only if it is configured.
- Print the txbuf size if configured.
This commit is contained in:
robert-hh 2022-08-18 11:58:09 +02:00 committed by Damien George
parent ddd41b8bbf
commit 2251cb774b
1 changed files with 49 additions and 4 deletions

View File

@ -116,9 +116,17 @@ void sercom_enable(Sercom *uart, int state) {
STATIC void machine_uart_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
machine_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
mp_printf(print, "UART(%u, baudrate=%u, bits=%u, parity=%s, stop=%u, "
"timeout=%u, timeout_char=%u, rxbuf=%d)",
"timeout=%u, timeout_char=%u, rxbuf=%d"
#if MICROPY_HW_UART_TXBUF
", txbuf=%d"
#endif
")",
self->id, self->baudrate, self->bits, _parity_name[self->parity],
self->stop + 1, self->timeout, self->timeout_char, self->read_buffer.size - 1);
self->stop + 1, self->timeout, self->timeout_char, self->read_buffer.size - 1
#if MICROPY_HW_UART_TXBUF
, self->write_buffer.size - 1
#endif
);
}
STATIC mp_obj_t machine_uart_init_helper(machine_uart_obj_t *self, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
@ -385,6 +393,22 @@ STATIC mp_obj_t machine_uart_sendbreak(mp_obj_t self_in) {
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_uart_sendbreak_obj, machine_uart_sendbreak);
STATIC mp_obj_t machine_uart_txdone(mp_obj_t self_in) {
machine_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
Sercom *uart = sercom_instance[self->id];
if (uart->USART.INTFLAG.bit.DRE
#if MICROPY_HW_UART_TXBUF
&& ringbuf_avail(&self->write_buffer) == 0
#endif
&& uart->USART.INTFLAG.bit.TXC) {
return mp_const_true;
} else {
return mp_const_false;
}
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_uart_txdone_obj, machine_uart_txdone);
void uart_deinit_all(void) {
for (int i = 0; i < SERCOM_INST_NUM; i++) {
if (uart_table[i] != NULL) {
@ -399,7 +423,9 @@ STATIC const mp_rom_map_elem_t machine_uart_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_any), MP_ROM_PTR(&machine_uart_any_obj) },
{ MP_ROM_QSTR(MP_QSTR_sendbreak), MP_ROM_PTR(&machine_uart_sendbreak_obj) },
{ MP_ROM_QSTR(MP_QSTR_txdone), MP_ROM_PTR(&machine_uart_txdone_obj) },
{ MP_ROM_QSTR(MP_QSTR_flush), MP_ROM_PTR(&mp_stream_flush_obj) },
{ MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
{ MP_ROM_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj) },
{ MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
@ -414,7 +440,6 @@ STATIC mp_uint_t machine_uart_read(mp_obj_t self_in, void *buf_in, mp_uint_t siz
uint8_t *dest = buf_in;
Sercom *uart = sercom_instance[self->id];
// t.b.d. Cater timeout for timer wrap after 50 days.
for (size_t i = 0; i < size; i++) {
// Wait for the first/next character
while (ringbuf_avail(&self->read_buffer) == 0) {
@ -488,9 +513,29 @@ STATIC mp_uint_t machine_uart_ioctl(mp_obj_t self_in, mp_uint_t request, mp_uint
if ((flags & MP_STREAM_POLL_RD) && (uart->USART.INTFLAG.bit.RXC != 0 || ringbuf_avail(&self->read_buffer) > 0)) {
ret |= MP_STREAM_POLL_RD;
}
if ((flags & MP_STREAM_POLL_WR) && (uart->USART.INTFLAG.bit.DRE != 0)) {
if ((flags & MP_STREAM_POLL_WR) && (uart->USART.INTFLAG.bit.DRE != 0
#if MICROPY_HW_UART_TXBUF
|| ringbuf_avail(&self->write_buffer) > 0
#endif
)) {
ret |= MP_STREAM_POLL_WR;
}
} else if (request == MP_STREAM_FLUSH) {
// The timeout is defined by the buffer size and the baudrate.
// Take the worst case assumtions at 13 bit symbol size times 2.
uint64_t timeout = mp_hal_ticks_ms_64() + (3
#if MICROPY_HW_UART_TXBUF
+ self->write_buffer.size
#endif
) * 13000 * 2 / self->baudrate;
do {
if (machine_uart_txdone((mp_obj_t)self) == mp_const_true) {
return 0;
}
MICROPY_EVENT_POLL_HOOK
} while (mp_hal_ticks_ms_64() < timeout);
*errcode = MP_ETIMEDOUT;
ret = MP_STREAM_ERROR;
} else {
*errcode = MP_EINVAL;
ret = MP_STREAM_ERROR;