extmod/machine_uart: Factor ports' UART Python bindings to common code.

This is a code factoring to have the Python bindings in one location, and
all the ports use those same bindings.  For all ports except the two listed
below there is no functional change.

The nrf port has UART.sendbreak() removed, but this method previously did
nothing.

The zephyr port has the following methods added:
- UART.init(): supports setting timeout and timeout_char.
- UART.deinit(): does nothing, just returns None.
- UART.flush(): raises OSError(EINVAL) because it's not implemented.
- UART.any() and UART.txdone(): raise NotImplementedError.

Signed-off-by: Damien George <damien@micropython.org>

drivers/cyw43/cywbt.c

@@ -49,7 +49,7 @@ extern uint8_t mp_bluetooth_hci_cmd_buf[4 + 256];
 #include "uart.h"
 
 // Provided by the port.
-extern pyb_uart_obj_t mp_bluetooth_hci_uart_obj;
+extern machine_uart_obj_t mp_bluetooth_hci_uart_obj;
 
 STATIC void cywbt_wait_cts_low(void) {
     mp_hal_pin_config(CYW43_PIN_BT_CTS, MP_HAL_PIN_MODE_INPUT, MP_HAL_PIN_PULL_UP, 0);

extmod/extmod.cmake

@@ -16,6 +16,7 @@ set(MICROPY_SOURCE_EXTMOD
     ${MICROPY_EXTMOD_DIR}/machine_pwm.c
     ${MICROPY_EXTMOD_DIR}/machine_signal.c
     ${MICROPY_EXTMOD_DIR}/machine_spi.c
+    ${MICROPY_EXTMOD_DIR}/machine_uart.c
     ${MICROPY_EXTMOD_DIR}/machine_wdt.c
     ${MICROPY_EXTMOD_DIR}/modbluetooth.c
     ${MICROPY_EXTMOD_DIR}/modframebuf.c

extmod/extmod.mk

@@ -13,6 +13,7 @@ SRC_EXTMOD_C += \
 	extmod/machine_signal.c \
 	extmod/machine_spi.c \
 	extmod/machine_timer.c \
+	extmod/machine_uart.c \
 	extmod/machine_wdt.c \
 	extmod/modasyncio.c \
 	extmod/modbinascii.c \

extmod/machine_uart.c

@@ -0,0 +1,187 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2023 Damien P. George
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "py/runtime.h"
+#include "py/stream.h"
+
+#if MICROPY_PY_MACHINE_UART
+
+#include "extmod/modmachine.h"
+#include "shared/runtime/mpirq.h"
+
+// The port must provide implementations of these low-level UART functions.
+
+STATIC void mp_machine_uart_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind);
+STATIC void mp_machine_uart_init_helper(machine_uart_obj_t *self, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args);
+STATIC mp_obj_t mp_machine_uart_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args);
+STATIC void mp_machine_uart_deinit(machine_uart_obj_t *self);
+STATIC mp_int_t mp_machine_uart_any(machine_uart_obj_t *self);
+STATIC bool mp_machine_uart_txdone(machine_uart_obj_t *self);
+
+#if MICROPY_PY_MACHINE_UART_SENDBREAK
+STATIC void mp_machine_uart_sendbreak(machine_uart_obj_t *self);
+#endif
+
+#if MICROPY_PY_MACHINE_UART_READCHAR_WRITECHAR
+STATIC mp_int_t mp_machine_uart_readchar(machine_uart_obj_t *self);
+STATIC void mp_machine_uart_writechar(machine_uart_obj_t *self, uint16_t data);
+#endif
+
+#if MICROPY_PY_MACHINE_UART_IRQ
+STATIC mp_irq_obj_t *mp_machine_uart_irq(machine_uart_obj_t *self, bool any_args, mp_arg_val_t *args);
+#endif
+
+STATIC mp_uint_t mp_machine_uart_read(mp_obj_t self_in, void *buf_in, mp_uint_t size, int *errcode);
+STATIC mp_uint_t mp_machine_uart_write(mp_obj_t self_in, const void *buf_in, mp_uint_t size, int *errcode);
+STATIC mp_uint_t mp_machine_uart_ioctl(mp_obj_t self_in, mp_uint_t request, uintptr_t arg, int *errcode);
+
+// The port provides implementations of the above in this file.
+#include MICROPY_PY_MACHINE_UART_INCLUDEFILE
+
+// UART.init(...)
+STATIC mp_obj_t machine_uart_init(size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
+    mp_machine_uart_init_helper(MP_OBJ_TO_PTR(args[0]), n_args - 1, args + 1, kw_args);
+    return mp_const_none;
+}
+MP_DEFINE_CONST_FUN_OBJ_KW(machine_uart_init_obj, 1, machine_uart_init);
+
+// UART.deinit()
+STATIC mp_obj_t machine_uart_deinit(mp_obj_t self_in) {
+    machine_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    mp_machine_uart_deinit(self);
+    return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_uart_deinit_obj, machine_uart_deinit);
+
+// UART.any()
+STATIC mp_obj_t machine_uart_any(mp_obj_t self_in) {
+    machine_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    return MP_OBJ_NEW_SMALL_INT(mp_machine_uart_any(self));
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_uart_any_obj, machine_uart_any);
+
+// UART.txdone()
+STATIC mp_obj_t machine_uart_txdone(mp_obj_t self_in) {
+    machine_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    return mp_obj_new_bool(mp_machine_uart_txdone(self));
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_uart_txdone_obj, machine_uart_txdone);
+
+#if MICROPY_PY_MACHINE_UART_SENDBREAK
+
+// UART.sendbreak()
+STATIC mp_obj_t machine_uart_sendbreak(mp_obj_t self_in) {
+    machine_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    mp_machine_uart_sendbreak(self);
+    return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_uart_sendbreak_obj, machine_uart_sendbreak);
+
+#endif
+
+#if MICROPY_PY_MACHINE_UART_READCHAR_WRITECHAR
+
+// UART.readchar()
+STATIC mp_obj_t machine_uart_readchar(mp_obj_t self_in) {
+    machine_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    return MP_OBJ_NEW_SMALL_INT(mp_machine_uart_readchar(self));
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_uart_readchar_obj, machine_uart_readchar);
+
+// UART.writechar(char)
+STATIC mp_obj_t machine_uart_writechar(mp_obj_t self_in, mp_obj_t char_in) {
+    machine_uart_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    mp_machine_uart_writechar(self, mp_obj_get_int(char_in));
+    return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_2(machine_uart_writechar_obj, machine_uart_writechar);
+
+#endif
+
+#if MICROPY_PY_MACHINE_UART_IRQ
+
+// UART.irq(handler, trigger, hard)
+STATIC mp_obj_t machine_uart_irq(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+    mp_arg_val_t args[MP_IRQ_ARG_INIT_NUM_ARGS];
+    mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_IRQ_ARG_INIT_NUM_ARGS, mp_irq_init_args, args);
+    machine_uart_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]);
+    bool any_args = n_args > 1 || kw_args->used != 0;
+    return MP_OBJ_FROM_PTR(mp_machine_uart_irq(self, any_args, args));
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_KW(machine_uart_irq_obj, 1, machine_uart_irq);
+
+#endif
+
+STATIC const mp_rom_map_elem_t machine_uart_locals_dict_table[] = {
+    { MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&machine_uart_init_obj) },
+    { MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&machine_uart_deinit_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) },
+    { MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_stream_write_obj) },
+
+    { MP_ROM_QSTR(MP_QSTR_any), MP_ROM_PTR(&machine_uart_any_obj) },
+    { MP_ROM_QSTR(MP_QSTR_txdone), MP_ROM_PTR(&machine_uart_txdone_obj) },
+
+    #if MICROPY_PY_MACHINE_UART_SENDBREAK
+    { MP_ROM_QSTR(MP_QSTR_sendbreak), MP_ROM_PTR(&machine_uart_sendbreak_obj) },
+    #endif
+
+    #if MICROPY_PY_MACHINE_UART_READCHAR_WRITECHAR
+    { MP_ROM_QSTR(MP_QSTR_readchar), MP_ROM_PTR(&machine_uart_readchar_obj) },
+    { MP_ROM_QSTR(MP_QSTR_writechar), MP_ROM_PTR(&machine_uart_writechar_obj) },
+    #endif
+
+    #if MICROPY_PY_MACHINE_UART_IRQ
+    { MP_ROM_QSTR(MP_QSTR_irq), MP_ROM_PTR(&machine_uart_irq_obj) },
+    #endif
+
+    // A port must add UART class constants defining the following macro.
+    // It can be defined to nothing if there are no constants.
+    MICROPY_PY_MACHINE_UART_CLASS_CONSTANTS
+};
+STATIC MP_DEFINE_CONST_DICT(machine_uart_locals_dict, machine_uart_locals_dict_table);
+
+STATIC const mp_stream_p_t uart_stream_p = {
+    .read = mp_machine_uart_read,
+    .write = mp_machine_uart_write,
+    .ioctl = mp_machine_uart_ioctl,
+    .is_text = false,
+};
+
+MP_DEFINE_CONST_OBJ_TYPE(
+    machine_uart_type,
+    MP_QSTR_UART,
+    MP_TYPE_FLAG_ITER_IS_STREAM,
+    make_new, mp_machine_uart_make_new,
+    print, mp_machine_uart_print,
+    protocol, &uart_stream_p,
+    locals_dict, &machine_uart_locals_dict
+    );
+
+#endif // MICROPY_PY_MACHINE_UART

extmod/modmachine.h

@@ -65,10 +65,29 @@
 #define MICROPY_PY_MACHINE_ADC_READ (0)
 #endif
 
+// Whether to enable the UART.sendbreak() method.
+// Requires a port to implement mp_machine_uart_sendbreak().
+#ifndef MICROPY_PY_MACHINE_UART_SENDBREAK
+#define MICROPY_PY_MACHINE_UART_SENDBREAK (0)
+#endif
+
+// Whether to enable the UART.readchar() and UART.writechar() methods.
+// Requires a port to implement mp_machine_uart_readchar() and mp_machine_uart_writechar().
+#ifndef MICROPY_PY_MACHINE_UART_READCHAR_WRITECHAR
+#define MICROPY_PY_MACHINE_UART_READCHAR_WRITECHAR (0)
+#endif
+
+// Whether to enable the UART.irq() method.
+// Requires a port to implement mp_machine_uart_irq().
+#ifndef MICROPY_PY_MACHINE_UART_IRQ
+#define MICROPY_PY_MACHINE_UART_IRQ (0)
+#endif
+
 // A port must provide these types, but they are otherwise opaque.
 typedef struct _machine_adc_obj_t machine_adc_obj_t;
 typedef struct _machine_i2s_obj_t machine_i2s_obj_t;
 typedef struct _machine_pwm_obj_t machine_pwm_obj_t;
+typedef struct _machine_uart_obj_t machine_uart_obj_t;
 typedef struct _machine_wdt_obj_t machine_wdt_obj_t;
 
 // These classes correspond to machine.Type entries in the machine module.
@@ -80,6 +99,7 @@ extern const mp_obj_type_t machine_i2s_type;
 extern const mp_obj_type_t machine_pwm_type;
 extern const mp_obj_type_t machine_spi_type;
 extern const mp_obj_type_t machine_timer_type;
+extern const mp_obj_type_t machine_uart_type;
 extern const mp_obj_type_t machine_wdt_type;
 
 #endif // MICROPY_INCLUDED_EXTMOD_MODMACHINE_H

ports/esp32/esp32_common.cmake

@@ -69,7 +69,6 @@ list(APPEND MICROPY_SOURCE_PORT
     machine_adcblock.c
     machine_dac.c
     machine_i2c.c
-    machine_uart.c
     modmachine.c
     network_common.c
     network_lan.c