Merge remote-tracking branch 'adafruit/main' into busio-uart-rp

8 files changed, 155 insertions, 55 deletions

diff --git a/py/circuitpy_defns.mk b/py/circuitpy_defns.mk
index 47870ede1..943c99f93 100644
--- a/py/circuitpy_defns.mk
+++ b/py/circuitpy_defns.mk
@@ -132,9 +132,6 @@ endif
 ifeq ($(CIRCUITPY_AUDIOMP3),1)
 SRC_PATTERNS += audiomp3/%
 endif
-ifeq ($(CIRCUITPY_BITOPS),1)
-SRC_PATTERNS += bitops/%
-endif
 ifeq ($(CIRCUITPY_BITBANGIO),1)
 SRC_PATTERNS += bitbangio/%
 endif
@@ -142,6 +139,9 @@ endif
 ifeq ($(CIRCUITPY_BITBANG_APA102),1)
 SRC_PATTERNS += bitbangio/SPI%
 endif
+ifeq ($(CIRCUITPY_BITOPS),1)
+SRC_PATTERNS += bitops/%
+endif
 ifeq ($(CIRCUITPY_BLEIO),1)
 SRC_PATTERNS += _bleio/%
 endif
@@ -289,6 +289,9 @@ endif
 ifeq ($(CIRCUITPY_UHEAP),1)
 SRC_PATTERNS += uheap/%
 endif
+ifeq ($(CIRCUITPY_USB_CDC),1)
+SRC_PATTERNS += usb_cdc/%
+endif
 ifeq ($(CIRCUITPY_USB_HID),1)
 SRC_PATTERNS += usb_hid/%
 endif
diff --git a/py/circuitpy_mpconfig.h b/py/circuitpy_mpconfig.h
index d72146c42..cbe668289 100644
--- a/py/circuitpy_mpconfig.h
+++ b/py/circuitpy_mpconfig.h
@@ -299,6 +299,13 @@ extern const struct _mp_obj_module_t audiopwmio_module;
 #define BINASCII_MODULE
 #endif
 
+#if CIRCUITPY_BITBANGIO
+#define BITBANGIO_MODULE       { MP_OBJ_NEW_QSTR(MP_QSTR_bitbangio), (mp_obj_t)&bitbangio_module },
+extern const struct _mp_obj_module_t bitbangio_module;
+#else
+#define BITBANGIO_MODULE
+#endif
+
 #if CIRCUITPY_BITOPS
 extern const struct _mp_obj_module_t bitops_module;
 #define BITOPS_MODULE        { MP_OBJ_NEW_QSTR(MP_QSTR_bitops),(mp_obj_t)&bitops_module },
@@ -307,13 +314,6 @@ extern const struct _mp_obj_module_t bitops_module;
 #endif
 
 
-#if CIRCUITPY_BITBANGIO
-#define BITBANGIO_MODULE       { MP_OBJ_NEW_QSTR(MP_QSTR_bitbangio), (mp_obj_t)&bitbangio_module },
-extern const struct _mp_obj_module_t bitbangio_module;
-#else
-#define BITBANGIO_MODULE
-#endif
-
 #if CIRCUITPY_BLEIO
 #define BLEIO_MODULE           { MP_OBJ_NEW_QSTR(MP_QSTR__bleio), (mp_obj_t)&bleio_module },
 extern const struct _mp_obj_module_t bleio_module;
@@ -744,6 +744,13 @@ extern const struct _mp_obj_module_t uheap_module;
 #define UHEAP_MODULE
 #endif
 
+#if CIRCUITPY_USB_CDC
+extern const struct _mp_obj_module_t usb_cdc_module;
+#define USB_CDC_MODULE         { MP_OBJ_NEW_QSTR(MP_QSTR_usb_cdc),(mp_obj_t)&usb_cdc_module },
+#else
+#define USB_CDC_MODULE
+#endif
+
 #if CIRCUITPY_USB_HID
 extern const struct _mp_obj_module_t usb_hid_module;
 #define USB_HID_MODULE         { MP_OBJ_NEW_QSTR(MP_QSTR_usb_hid),(mp_obj_t)&usb_hid_module },
@@ -827,8 +834,8 @@ extern const struct _mp_obj_module_t msgpack_module;
     AUDIOMP3_MODULE \
     AUDIOPWMIO_MODULE \
     BINASCII_MODULE \
-    BITOPS_MODULE \
     BITBANGIO_MODULE \
+    BITOPS_MODULE \
     BLEIO_MODULE \
     BOARD_MODULE \
     BUSDEVICE_MODULE \
@@ -884,6 +891,7 @@ extern const struct _mp_obj_module_t msgpack_module;
     SUPERVISOR_MODULE \
     TOUCHIO_MODULE \
     UHEAP_MODULE \
+    USB_CDC_MODULE \
     USB_HID_MODULE \
     USB_MIDI_MODULE \
     USTACK_MODULE \
diff --git a/py/circuitpy_mpconfig.mk b/py/circuitpy_mpconfig.mk
index 6244ed136..ad6386636 100644
--- a/py/circuitpy_mpconfig.mk
+++ b/py/circuitpy_mpconfig.mk
@@ -89,12 +89,15 @@ CFLAGS += -DCIRCUITPY_AUDIOMP3=$(CIRCUITPY_AUDIOMP3)
 CIRCUITPY_BINASCII ?= $(CIRCUITPY_FULL_BUILD)
 CFLAGS += -DCIRCUITPY_BINASCII=$(CIRCUITPY_BINASCII)
 
-CIRCUITPY_BITOPS ?= 0
-CFLAGS += -DCIRCUITPY_BITOPS=$(CIRCUITPY_BITOPS)
+CIRCUITPY_BITBANG_APA102 ?= 0
+CFLAGS += -DCIRCUITPY_BITBANG_APA102=$(CIRCUITPY_BITBANG_APA102)
 
 CIRCUITPY_BITBANGIO ?= $(CIRCUITPY_FULL_BUILD)
 CFLAGS += -DCIRCUITPY_BITBANGIO=$(CIRCUITPY_BITBANGIO)
 
+CIRCUITPY_BITOPS ?= 0
+CFLAGS += -DCIRCUITPY_BITOPS=$(CIRCUITPY_BITOPS)
+
 # _bleio can be supported on most any board via HCI
 CIRCUITPY_BLEIO_HCI ?= $(CIRCUITPY_FULL_BUILD)
 CFLAGS += -DCIRCUITPY_BLEIO_HCI=$(CIRCUITPY_BLEIO_HCI)
@@ -103,6 +106,9 @@ CFLAGS += -DCIRCUITPY_BLEIO_HCI=$(CIRCUITPY_BLEIO_HCI)
 CIRCUITPY_BLEIO ?= $(CIRCUITPY_BLEIO_HCI)
 CFLAGS += -DCIRCUITPY_BLEIO=$(CIRCUITPY_BLEIO)
 
+CIRCUITPY_BLE_FILE_SERVICE ?= 0
+CFLAGS += -DCIRCUITPY_BLE_FILE_SERVICE=$(CIRCUITPY_BLE_FILE_SERVICE)
+
 CIRCUITPY_BOARD ?= 1
 CFLAGS += -DCIRCUITPY_BOARD=$(CIRCUITPY_BOARD)
 
@@ -130,6 +136,13 @@ CFLAGS += -DCIRCUITPY_COUNTIO=$(CIRCUITPY_COUNTIO)
 CIRCUITPY_DISPLAYIO ?= $(CIRCUITPY_FULL_BUILD)
 CFLAGS += -DCIRCUITPY_DISPLAYIO=$(CIRCUITPY_DISPLAYIO)
 
+CIRCUITPY_DUALBANK ?= 0
+CFLAGS += -DCIRCUITPY_DUALBANK=$(CIRCUITPY_DUALBANK)
+
+# Enabled micropython.native decorator (experimental)
+CIRCUITPY_ENABLE_MPY_NATIVE ?= 0
+CFLAGS += -DCIRCUITPY_ENABLE_MPY_NATIVE=$(CIRCUITPY_ENABLE_MPY_NATIVE)
+
 CIRCUITPY_ERRNO ?= $(CIRCUITPY_FULL_BUILD)
 CFLAGS += -DCIRCUITPY_ERRNO=$(CIRCUITPY_ERRNO)
 
@@ -182,6 +195,9 @@ CFLAGS += -DCIRCUITPY_MEMORYMONITOR=$(CIRCUITPY_MEMORYMONITOR)
 CIRCUITPY_MICROCONTROLLER ?= 1
 CFLAGS += -DCIRCUITPY_MICROCONTROLLER=$(CIRCUITPY_MICROCONTROLLER)
 
+CIRCUITPY_MSGPACK ?= $(CIRCUITPY_FULL_BUILD)
+CFLAGS += -DCIRCUITPY_MSGPACK=$(CIRCUITPY_MSGPACK)
+
 CIRCUITPY_NEOPIXEL_WRITE ?= 1
 CFLAGS += -DCIRCUITPY_NEOPIXEL_WRITE=$(CIRCUITPY_NEOPIXEL_WRITE)
 
@@ -195,8 +211,8 @@ CFLAGS += -DCIRCUITPY_NVM=$(CIRCUITPY_NVM)
 CIRCUITPY_OS ?= 1
 CFLAGS += -DCIRCUITPY_OS=$(CIRCUITPY_OS)
 
-CIRCUITPY_DUALBANK ?= 0
-CFLAGS += -DCIRCUITPY_DUALBANK=$(CIRCUITPY_DUALBANK)
+CIRCUITPY_PEW ?= 0
+CFLAGS += -DCIRCUITPY_PEW=$(CIRCUITPY_PEW)
 
 CIRCUITPY_PIXELBUF ?= $(CIRCUITPY_FULL_BUILD)
 CFLAGS += -DCIRCUITPY_PIXELBUF=$(CIRCUITPY_PIXELBUF)
@@ -219,6 +235,20 @@ CFLAGS += -DCIRCUITPY_RANDOM=$(CIRCUITPY_RANDOM)
 CIRCUITPY_RE ?= $(CIRCUITPY_FULL_BUILD)
 CFLAGS += -DCIRCUITPY_RE=$(CIRCUITPY_RE)
 
+CIRCUITPY_REPL_BLE ?= 0
+CFLAGS += -DCIRCUITPY_REPL_BLE=$(CIRCUITPY_REPL_BLE)
+
+CIRCUITPY_REPL_UART ?= 0
+CFLAGS += -DCIRCUITPY_REPL_UART=$(CIRCUITPY_REPL_UART)
+
+CIRCUITPY_REPL_USB ?= 1
+CFLAGS += -DCIRCUITPY_REPL_USB=$(CIRCUITPY_REPL_USB)
+
+# Should busio.I2C() check for pullups?
+# Some boards in combination with certain peripherals may not want this.
+CIRCUITPY_REQUIRE_I2C_PULLUPS ?= 1
+CFLAGS += -DCIRCUITPY_REQUIRE_I2C_PULLUPS=$(CIRCUITPY_REQUIRE_I2C_PULLUPS)
+
 # CIRCUITPY_RP2PIO is handled in the raspberrypi tree.
 # Only for rp2 chips.
 # Assume not a rp2 build.
@@ -285,46 +315,54 @@ CFLAGS += -DCIRCUITPY_TOUCHIO=$(CIRCUITPY_TOUCHIO)
 CIRCUITPY_UHEAP ?= 0
 CFLAGS += -DCIRCUITPY_UHEAP=$(CIRCUITPY_UHEAP)
 
+# Secondary CDC is usually available if there are at least 8 endpoints.
+CIRCUITPY_USB_CDC ?= $(shell expr $(USB_NUM_EP) '>=' 8)
+CFLAGS += -DCIRCUITPY_USB_CDC=$(CIRCUITPY_USB_CDC)
+
 CIRCUITPY_USB_HID ?= 1
 CFLAGS += -DCIRCUITPY_USB_HID=$(CIRCUITPY_USB_HID)
 
+CIRCUITPY_USB_HID_CONSUMER ?= 1
+CFLAGS += -DCIRCUITPY_USB_HID_CONSUMER=$(CIRCUITPY_USB_HID_CONSUMER)
+
+CIRCUITPY_USB_HID_DIGITIZER ?= 0
+CFLAGS += -DCIRCUITPY_USB_HID_DIGITIZER=$(CIRCUITPY_USB_HID_DIGITIZER)
+
+CIRCUITPY_USB_HID_GAMEPAD ?= 1
+CFLAGS += -DCIRCUITPY_USB_HID_GAMEPAD=$(CIRCUITPY_USB_HID_GAMEPAD)
+
+CIRCUITPY_USB_HID_KEYBOARD ?= 1
+CFLAGS += -DCIRCUITPY_USB_HID_KEYBOARD=$(CIRCUITPY_USB_HID_KEYBOARD)
+
+CIRCUITPY_USB_HID_MOUSE ?= 1
+CFLAGS += -DCIRCUITPY_USB_HID_MOUSE=$(CIRCUITPY_USB_HID_MOUSE)
+
+CIRCUITPY_USB_HID_SYS_CONTROL ?= 0
+CFLAGS += -DCIRCUITPY_USB_HID_SYS_CONTROL=$(CIRCUITPY_USB_HID_SYS_CONTROL)
+
+CIRCUITPY_USB_HID_XAC_COMPATIBLE_GAMEPAD ?= 0
+CFLAGS += -DCIRCUITPY_USB_HID_XAC_COMPATIBLE_GAMEPAD=$(CIRCUITPY_USB_HID_XAC_COMPATIBLE_GAMEPAD)
+
 CIRCUITPY_USB_MIDI ?= 1
 CFLAGS += -DCIRCUITPY_USB_MIDI=$(CIRCUITPY_USB_MIDI)
 
+CIRCUITPY_USB_MSC ?= 1
+CFLAGS += -DCIRCUITPY_USB_MSC=$(CIRCUITPY_USB_MSC)
+
 # Defaulting this to OFF initially because it has only been tested on a
 # limited number of platforms, and the other platforms do not have this
 # setting in their mpconfigport.mk and/or mpconfigboard.mk files yet.
 CIRCUITPY_USB_VENDOR ?= 0
 CFLAGS += -DCIRCUITPY_USB_VENDOR=$(CIRCUITPY_USB_VENDOR)
 
-CIRCUITPY_PEW ?= 0
-CFLAGS += -DCIRCUITPY_PEW=$(CIRCUITPY_PEW)
+ifndef USB_NUM_EP
+$(error "USB_NUM_EP (number of USB endpoint pairs)must be defined")
+endif
 
 # For debugging.
 CIRCUITPY_USTACK ?= 0
 CFLAGS += -DCIRCUITPY_USTACK=$(CIRCUITPY_USTACK)
 
-# Non-module conditionals
-
-CIRCUITPY_BITBANG_APA102 ?= 0
-CFLAGS += -DCIRCUITPY_BITBANG_APA102=$(CIRCUITPY_BITBANG_APA102)
-
-# Should busio.I2C() check for pullups?
-# Some boards in combination with certain peripherals may not want this.
-CIRCUITPY_REQUIRE_I2C_PULLUPS ?= 1
-CFLAGS += -DCIRCUITPY_REQUIRE_I2C_PULLUPS=$(CIRCUITPY_REQUIRE_I2C_PULLUPS)
-
-# REPL over BLE
-CIRCUITPY_SERIAL_BLE ?= 0
-CFLAGS += -DCIRCUITPY_SERIAL_BLE=$(CIRCUITPY_SERIAL_BLE)
-
-CIRCUITPY_BLE_FILE_SERVICE ?= 0
-CFLAGS += -DCIRCUITPY_BLE_FILE_SERVICE=$(CIRCUITPY_BLE_FILE_SERVICE)
-
-# REPL over UART
-CIRCUITPY_SERIAL_UART ?= 0
-CFLAGS += -DCIRCUITPY_SERIAL_UART=$(CIRCUITPY_SERIAL_UART)
-
 # ulab numerics library
 CIRCUITPY_ULAB ?= $(CIRCUITPY_FULL_BUILD)
 CFLAGS += -DCIRCUITPY_ULAB=$(CIRCUITPY_ULAB)
@@ -335,10 +373,3 @@ CFLAGS += -DCIRCUITPY_WATCHDOG=$(CIRCUITPY_WATCHDOG)
 
 CIRCUITPY_WIFI ?= 0
 CFLAGS += -DCIRCUITPY_WIFI=$(CIRCUITPY_WIFI)
-
-# Enabled micropython.native decorator (experimental)
-CIRCUITPY_ENABLE_MPY_NATIVE ?= 0
-CFLAGS += -DCIRCUITPY_ENABLE_MPY_NATIVE=$(CIRCUITPY_ENABLE_MPY_NATIVE)
-
-CIRCUITPY_MSGPACK ?= $(CIRCUITPY_FULL_BUILD)
-CFLAGS += -DCIRCUITPY_MSGPACK=$(CIRCUITPY_MSGPACK)
diff --git a/py/obj.h b/py/obj.h
index 066562cc4..c3ab63b5c 100644
--- a/py/obj.h
+++ b/py/obj.h
@@ -684,6 +684,7 @@ mp_obj_t mp_obj_new_bytearray_by_ref(size_t n, void *items);
 mp_obj_t mp_obj_new_int_from_float(mp_float_t val);
 mp_obj_t mp_obj_new_complex(mp_float_t real, mp_float_t imag);
 extern mp_float_t uint64_to_float(uint64_t ui64);
+extern uint64_t float_to_uint64(float f);
 #endif
 mp_obj_t mp_obj_new_exception(const mp_obj_type_t *exc_type);
 mp_obj_t mp_obj_new_exception_arg1(const mp_obj_type_t *exc_type, mp_obj_t arg);
diff --git a/py/objarray.c b/py/objarray.c
index e0b4cbd55..9640f596a 100644
--- a/py/objarray.c
+++ b/py/objarray.c
@@ -238,6 +238,26 @@ STATIC mp_obj_t memoryview_make_new(const mp_obj_type_t *type_in, size_t n_args,
 
     return MP_OBJ_FROM_PTR(self);
 }
+
+#if MICROPY_CPYTHON_COMPAT
+STATIC mp_obj_t memoryview_cast(const mp_obj_t self_in, const mp_obj_t typecode_in) {
+    mp_obj_array_t *self = MP_OBJ_TO_PTR(self_in);
+    const char *typecode = mp_obj_str_get_str(typecode_in);
+    size_t element_size = mp_binary_get_size('@', typecode[0], NULL);
+    size_t bytelen = self->len * mp_binary_get_size('@', self->typecode & ~MP_OBJ_ARRAY_TYPECODE_FLAG_RW, NULL);
+    if (bytelen % element_size != 0) {
+        mp_raise_TypeError(translate("memoryview: length is not a multiple of itemsize"));
+    }
+    mp_obj_array_t *result = MP_OBJ_TO_PTR(mp_obj_new_memoryview(*typecode, bytelen / element_size, self->items));
+
+    // test if the object can be written to
+    if (self->typecode & MP_OBJ_ARRAY_TYPECODE_FLAG_RW) {
+        result->typecode |= MP_OBJ_ARRAY_TYPECODE_FLAG_RW; // indicate writable buffer
+    }
+    return MP_OBJ_FROM_PTR(result);
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_2(memoryview_cast_obj, memoryview_cast);
+#endif
 #endif
 
 STATIC mp_obj_t array_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
@@ -691,6 +711,15 @@ const mp_obj_type_t mp_type_bytearray = {
 #endif
 
 #if MICROPY_PY_BUILTINS_MEMORYVIEW
+
+#if MICROPY_CPYTHON_COMPAT
+STATIC const mp_rom_map_elem_t memoryview_locals_dict_table[] = {
+    { MP_ROM_QSTR(MP_QSTR_cast), MP_ROM_PTR(&memoryview_cast_obj) },
+};
+
+STATIC MP_DEFINE_CONST_DICT(memoryview_locals_dict, memoryview_locals_dict_table);
+#endif
+
 const mp_obj_type_t mp_type_memoryview = {
     { &mp_type_type },
     .name = MP_QSTR_memoryview,
@@ -700,6 +729,9 @@ const mp_obj_type_t mp_type_memoryview = {
     .binary_op = array_binary_op,
     .subscr = array_subscr,
     .buffer_p = { .get_buffer = array_get_buffer },
+#if MICROPY_CPYTHON_COMPAT
+    .locals_dict = (mp_obj_dict_t*)&memoryview_locals_dict,
+#endif
 };
 #endif
 
diff --git a/py/objfloat.c b/py/objfloat.c
index 80f10e816..329a8b90e 100644
--- a/py/objfloat.c
+++ b/py/objfloat.c
@@ -340,6 +340,15 @@ mp_float_t uint64_to_float(uint64_t ui64) {
     return (mp_float_t) ((uint32_t) (ui64 >> 32) * 4294967296.0f + (uint32_t) (ui64 & 0xffffffff));
 }
 
+// Convert a uint64_t to a 32-bit float to a uint64_t without invoking extra math routines.
+// which are large.
+// Assume f >= 0.
+uint64_t float_to_uint64(float f) {
+    // 4294967296 = 2^32
+    const uint32_t upper_half = (uint32_t) (f /  4294967296.0f);
+    const uint32_t lower_half = (uint32_t) f;
+    return (((uint64_t) upper_half) << 32) + lower_half;
+}
 #pragma GCC diagnostic pop
 
 #endif // MICROPY_PY_BUILTINS_FLOAT
diff --git a/py/stream.c b/py/stream.c
index ae702bb1b..0813c1d7f 100644
--- a/py/stream.c
+++ b/py/stream.c
@@ -99,14 +99,22 @@ const mp_stream_p_t *mp_get_stream_raise(mp_obj_t self_in, int flags) {
 
 STATIC mp_obj_t stream_read_generic(size_t n_args, const mp_obj_t *args, byte flags) {
     // What to do if sz < -1?  Python docs don't specify this case.
-    // CPython does a readall, but here we silently let negatives through,
-    // and they will cause a MemoryError.
+    // CPython does a readall, let's do the same.
     mp_int_t sz;
-    if (n_args == 1 || args[1] == mp_const_none || ((sz = mp_obj_get_int(args[1])) == -1)) {
-        return stream_readall(args[0]);
-    }
-
     const mp_stream_p_t *stream_p = mp_get_stream(args[0]);
+    if (stream_p->pyserial_read_compatibility) {
+        // Pyserial defaults to sz=1 if not specified.
+        if (n_args == 1) {
+            sz = 1;
+        } else {
+            // Pyserial treats negative size as 0.
+            sz = MAX(0, mp_obj_get_int(args[1]));
+        }
+    } else {
+        if (n_args == 1 || args[1] == mp_const_none || (sz = mp_obj_get_int(args[1])) <= -1) {
+            return stream_readall(args[0]);
+        }
+    }
 
     #if MICROPY_PY_BUILTINS_STR_UNICODE
     if (stream_p->is_text) {
@@ -284,7 +292,7 @@ STATIC mp_obj_t stream_readinto(size_t n_args, const mp_obj_t *args) {
     // https://docs.python.org/3/library/socket.html#socket.socket.recv_into
     mp_uint_t len = bufinfo.len;
     if (n_args > 2) {
-        if (mp_get_stream(args[0])->pyserial_compatibility) {
+        if (mp_get_stream(args[0])->pyserial_readinto_compatibility) {
             mp_raise_ValueError(translate("length argument not allowed for this type"));
         }
         len = mp_obj_get_int(args[2]);
@@ -297,7 +305,10 @@ STATIC mp_obj_t stream_readinto(size_t n_args, const mp_obj_t *args) {
     mp_uint_t out_sz = mp_stream_read_exactly(args[0], bufinfo.buf, len, &error);
     if (error != 0) {
         if (mp_is_nonblocking_error(error)) {
-            return mp_const_none;
+            // pyserial readinto never returns None, just 0.
+            return mp_get_stream(args[0])->pyserial_dont_return_none_compatibility
+                ? MP_OBJ_NEW_SMALL_INT(0)
+                : mp_const_none;
         }
         mp_raise_OSError(error);
     } else {
@@ -323,7 +334,10 @@ STATIC mp_obj_t stream_readall(mp_obj_t self_in) {
                 // If we read nothing, return None, just like read().
                 // Otherwise, return data read so far.
                 if (total_size == 0) {
-                    return mp_const_none;
+                    // pyserial read() never returns None, just b''.
+                    return stream_p->pyserial_dont_return_none_compatibility
+                        ? mp_const_empty_bytes
+                        : mp_const_none;
                 }
                 break;
             }
diff --git a/py/stream.h b/py/stream.h
index be6b23d40..c05dcfc50 100644
--- a/py/stream.h
+++ b/py/stream.h
@@ -72,7 +72,9 @@ typedef struct _mp_stream_p_t {
     mp_uint_t (*write)(mp_obj_t obj, const void *buf, mp_uint_t size, int *errcode);
     mp_uint_t (*ioctl)(mp_obj_t obj, mp_uint_t request, uintptr_t arg, int *errcode);
     mp_uint_t is_text : 1; // default is bytes, set this for text stream
-    bool pyserial_compatibility: 1;  // adjust API to match pyserial more closely
+    bool pyserial_readinto_compatibility: 1;         // Disallow size parameter in readinto()
+    bool pyserial_read_compatibility: 1;             // Disallow omitting read(size) size parameter
+    bool pyserial_dont_return_none_compatibility: 1; // Don't return None for read() or readinto()
 } mp_stream_p_t;
 
 MP_DECLARE_CONST_FUN_OBJ_VAR_BETWEEN(mp_stream_read_obj);