From a70b679ed52529f8cc317959b180fd8a34bd220d Mon Sep 17 00:00:00 2001 From: Jeff Epler Date: Fri, 26 Mar 2021 12:06:25 -0500 Subject: [PATCH] bitbangio.SPI.read: Support write_value, fix some other nits --- shared-bindings/bitbangio/SPI.c | 48 ++++++++++++++++++++++++--------- shared-bindings/bitbangio/SPI.h | 2 +- shared-module/bitbangio/SPI.c | 8 ++++-- 3 files changed, 42 insertions(+), 16 deletions(-) diff --git a/shared-bindings/bitbangio/SPI.c b/shared-bindings/bitbangio/SPI.c index e0fc6682e4..1caa658df8 100644 --- a/shared-bindings/bitbangio/SPI.c +++ b/shared-bindings/bitbangio/SPI.c @@ -224,32 +224,53 @@ STATIC mp_obj_t bitbangio_spi_write(mp_obj_t self_in, mp_obj_t wr_buf) { MP_DEFINE_CONST_FUN_OBJ_2(bitbangio_spi_write_obj, bitbangio_spi_write); -//| def readinto(self, buf: WriteableBuffer) -> None: -//| """Read into the buffer specified by ``buf`` while writing zeroes. -//| Requires the SPI being locked. -//| If the number of bytes to read is 0, nothing happens.""" +//| def readinto(self, buffer: WriteableBuffer, *, start: int = 0, end: Optional[int] = None, write_value: int = 0) -> None: +//| """Read into ``buffer`` while writing ``write_value`` for each byte read. +//| The SPI object must be locked. +//| If the number of bytes to read is 0, nothing happens. +//| +//| :param bytearray buffer: Read data into this buffer +//| :param int start: Start of the slice of ``buffer`` to read into: ``buffer[start:end]`` +//| :param int end: End of the slice; this index is not included. Defaults to ``len(buffer)`` +//| :param int write_value: Value to write while reading.""" //| ... //| -// TODO(tannewt): Add support for start and end kwargs. -STATIC mp_obj_t bitbangio_spi_readinto(size_t n_args, const mp_obj_t *args) { - bitbangio_spi_obj_t *self = MP_OBJ_TO_PTR(args[0]); + +STATIC mp_obj_t bitbangio_spi_readinto(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) { + enum { ARG_buffer, ARG_start, ARG_end, ARG_write_value }; + static const mp_arg_t allowed_args[] = { + { MP_QSTR_buffer, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} }, + { MP_QSTR_start, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} }, + { MP_QSTR_end, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = INT_MAX} }, + { MP_QSTR_write_value,MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} }, + }; + bitbangio_spi_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]); check_for_deinit(self); + check_lock(self); + mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)]; + mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args); + mp_buffer_info_t bufinfo; - mp_get_buffer_raise(args[1], &bufinfo, MP_BUFFER_WRITE); - if (bufinfo.len == 0) { + mp_get_buffer_raise(args[ARG_buffer].u_obj, &bufinfo, MP_BUFFER_WRITE); + int32_t start = args[ARG_start].u_int; + size_t length = bufinfo.len; + normalize_buffer_bounds(&start, args[ARG_end].u_int, &length); + + if (length == 0) { return mp_const_none; } - check_lock(args[0]); - bool ok = shared_module_bitbangio_spi_read(self, bufinfo.buf, bufinfo.len); + + bool ok = shared_module_bitbangio_spi_read(self, ((uint8_t*)bufinfo.buf) + start, length, args[ARG_write_value].u_int); if (!ok) { mp_raise_OSError(MP_EIO); } return mp_const_none; } -MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(bitbangio_spi_readinto_obj, 2, 2, bitbangio_spi_readinto); +MP_DEFINE_CONST_FUN_OBJ_KW(bitbangio_spi_readinto_obj, 2, bitbangio_spi_readinto); -//| def write_readinto(self, buffer_out: ReadableBuffer, buffer_in: WriteableBuffer, *, out_start: int = 0, out_end: Optional[int] = None, in_start: int = 0, in_end: Optional[int] = None) -> None: +//| def write_readinto(self, buffer_out: ReadableBuffer, buffer_in: ReadableBuffer, *, out_start: int = 0, out_end: Optional[int] = None, in_start: int = 0, in_end: Optional[int] = None) -> None: //| """Write out the data in ``buffer_out`` while simultaneously reading data into ``buffer_in``. +//| The SPI object must be locked. //| The lengths of the slices defined by ``buffer_out[out_start:out_end]`` and ``buffer_in[in_start:in_end]`` //| must be equal. //| If buffer slice lengths are both 0, nothing happens. @@ -274,6 +295,7 @@ STATIC mp_obj_t bitbangio_spi_write_readinto(size_t n_args, const mp_obj_t *pos_ }; bitbangio_spi_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]); check_for_deinit(self); + check_lock(self); mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)]; mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args); diff --git a/shared-bindings/bitbangio/SPI.h b/shared-bindings/bitbangio/SPI.h index b2a6445754..2d0d75e407 100644 --- a/shared-bindings/bitbangio/SPI.h +++ b/shared-bindings/bitbangio/SPI.h @@ -54,7 +54,7 @@ extern void shared_module_bitbangio_spi_unlock(bitbangio_spi_obj_t *self); extern bool shared_module_bitbangio_spi_write(bitbangio_spi_obj_t *self, const uint8_t *data, size_t len); // Reads in len bytes while outputting zeroes. -extern bool shared_module_bitbangio_spi_read(bitbangio_spi_obj_t *self, uint8_t *data, size_t len); +extern bool shared_module_bitbangio_spi_read(bitbangio_spi_obj_t *self, uint8_t *data, size_t len, uint8_t write_value); // Transfer out len bytes while reading len bytes extern bool shared_module_bitbangio_spi_transfer(bitbangio_spi_obj_t *self, const uint8_t *dout, uint8_t *din, size_t len); diff --git a/shared-module/bitbangio/SPI.c b/shared-module/bitbangio/SPI.c index 8be6cac5fa..65511964a6 100644 --- a/shared-module/bitbangio/SPI.c +++ b/shared-module/bitbangio/SPI.c @@ -176,7 +176,7 @@ bool shared_module_bitbangio_spi_write(bitbangio_spi_obj_t *self, const uint8_t } // Reads in len bytes while outputting zeroes. -bool shared_module_bitbangio_spi_read(bitbangio_spi_obj_t *self, uint8_t *data, size_t len) { +bool shared_module_bitbangio_spi_read(bitbangio_spi_obj_t *self, uint8_t *data, size_t len, uint8_t write_data) { if (len > 0 && !self->has_miso) { mp_raise_ValueError(translate("Cannot read without MISO pin.")); } @@ -210,8 +210,12 @@ bool shared_module_bitbangio_spi_read(bitbangio_spi_obj_t *self, uint8_t *data, common_hal_digitalio_digitalinout_set_value(&self->mosi, false); } for (size_t i = 0; i < len; ++i) { + uint8_t data_out = write_data; uint8_t data_in = 0; - for (int j = 0; j < 8; ++j) { + for (int j = 0; j < 8; ++j, data_out <<= 1) { + if (self->has_mosi) { + common_hal_digitalio_digitalinout_set_value(&self->mosi, (data_out >> 7) & 1); + } if (self->phase == 0) { common_hal_mcu_delay_us(delay_half); common_hal_digitalio_digitalinout_set_value(&self->clock, 1 - self->polarity);