340 lines
11 KiB
C
340 lines
11 KiB
C
/*
|
|
* SPI Master library for nRF5x.
|
|
*
|
|
* Copyright (c) 2019 Dan Halbert for Adafruit Industries
|
|
* Copyright (c) 2018 Artur Pacholec
|
|
* Copyright (c) 2017 hathach
|
|
* Copyright (c) 2016 Sandeep Mistry All right reserved.
|
|
* Copyright (c) 2015 Arduino LLC
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#include "shared-bindings/busio/SPI.h"
|
|
#include "py/mperrno.h"
|
|
#include "py/runtime.h"
|
|
|
|
#include "nrfx_spim.h"
|
|
#include "nrf_gpio.h"
|
|
|
|
STATIC spim_peripheral_t spim_peripherals[] = {
|
|
#if NRFX_CHECK(NRFX_SPIM3_ENABLED)
|
|
// SPIM3 exists only on nRF52840 and supports 32MHz max. All other SPIM's are only 8MHz max.
|
|
// Allocate SPIM3 first.
|
|
{ .spim = NRFX_SPIM_INSTANCE(3),
|
|
.max_frequency_MHz = 32,
|
|
.max_xfer_size = SPIM3_EASYDMA_MAXCNT_SIZE,
|
|
},
|
|
#endif
|
|
#if NRFX_CHECK(NRFX_SPIM2_ENABLED)
|
|
// SPIM2 is not shared with a TWIM, so allocate before the shared ones.
|
|
{ .spim = NRFX_SPIM_INSTANCE(2),
|
|
.max_frequency_MHz = 8,
|
|
.max_xfer_size = SPIM2_EASYDMA_MAXCNT_SIZE,
|
|
},
|
|
#endif
|
|
#if NRFX_CHECK(NRFX_SPIM1_ENABLED)
|
|
// SPIM1 and TWIM1 share an address.
|
|
{ .spim = NRFX_SPIM_INSTANCE(1),
|
|
.max_frequency_MHz = 8,
|
|
.max_xfer_size = SPIM1_EASYDMA_MAXCNT_SIZE,
|
|
},
|
|
#endif
|
|
#if NRFX_CHECK(NRFX_SPIM0_ENABLED)
|
|
// SPIM0 and TWIM0 share an address.
|
|
{ .spim = NRFX_SPIM_INSTANCE(0),
|
|
.max_frequency_MHz = 8,
|
|
.max_xfer_size = SPIM0_EASYDMA_MAXCNT_SIZE,
|
|
},
|
|
#endif
|
|
};
|
|
|
|
STATIC bool never_reset[MP_ARRAY_SIZE(spim_peripherals)];
|
|
|
|
void spi_reset(void) {
|
|
for (size_t i = 0 ; i < MP_ARRAY_SIZE(spim_peripherals); i++) {
|
|
if (never_reset[i]) {
|
|
continue;
|
|
}
|
|
nrf_spim_disable(spim_peripherals[i].spim.p_reg);
|
|
}
|
|
}
|
|
|
|
void common_hal_busio_spi_never_reset(busio_spi_obj_t *self) {
|
|
for (size_t i = 0 ; i < MP_ARRAY_SIZE(spim_peripherals); i++) {
|
|
if (self->spim_peripheral == &spim_peripherals[i]) {
|
|
never_reset[i] = true;
|
|
|
|
never_reset_pin_number(self->clock_pin_number);
|
|
never_reset_pin_number(self->MOSI_pin_number);
|
|
never_reset_pin_number(self->MISO_pin_number);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Convert frequency to clock-speed-dependent value. Choose the next lower baudrate if in between
|
|
// available baudrates.
|
|
static nrf_spim_frequency_t baudrate_to_spim_frequency(const uint32_t baudrate) {
|
|
|
|
static const struct {
|
|
const uint32_t boundary;
|
|
nrf_spim_frequency_t spim_frequency;
|
|
} baudrate_map[] = {
|
|
#ifdef SPIM_FREQUENCY_FREQUENCY_M32
|
|
{ 32000000, NRF_SPIM_FREQ_32M },
|
|
#endif
|
|
#ifdef SPIM_FREQUENCY_FREQUENCY_M16
|
|
{ 16000000, NRF_SPIM_FREQ_16M },
|
|
#endif
|
|
{ 8000000, NRF_SPIM_FREQ_8M },
|
|
{ 4000000, NRF_SPIM_FREQ_4M },
|
|
{ 2000000, NRF_SPIM_FREQ_2M },
|
|
{ 1000000, NRF_SPIM_FREQ_1M },
|
|
{ 500000, NRF_SPIM_FREQ_500K },
|
|
{ 250000, NRF_SPIM_FREQ_250K },
|
|
{ 0, NRF_SPIM_FREQ_125K },
|
|
};
|
|
|
|
size_t i = 0;
|
|
uint32_t boundary;
|
|
do {
|
|
boundary = baudrate_map[i].boundary;
|
|
if (baudrate >= boundary) {
|
|
return baudrate_map[i].spim_frequency;
|
|
}
|
|
i++;
|
|
} while (boundary != 0);
|
|
// Should not get here.
|
|
return 0;
|
|
}
|
|
|
|
void common_hal_busio_spi_construct(busio_spi_obj_t *self, const mcu_pin_obj_t * clock, const mcu_pin_obj_t * mosi, const mcu_pin_obj_t * miso) {
|
|
// Find a free instance.
|
|
self->spim_peripheral = NULL;
|
|
for (size_t i = 0 ; i < MP_ARRAY_SIZE(spim_peripherals); i++) {
|
|
if ((spim_peripherals[i].spim.p_reg->ENABLE & SPIM_ENABLE_ENABLE_Msk) == 0) {
|
|
self->spim_peripheral = &spim_peripherals[i];
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (self->spim_peripheral == NULL) {
|
|
mp_raise_ValueError(translate("All SPI peripherals are in use"));
|
|
}
|
|
|
|
nrfx_spim_config_t config = NRFX_SPIM_DEFAULT_CONFIG;
|
|
config.frequency = NRF_SPIM_FREQ_8M;
|
|
|
|
config.sck_pin = clock->number;
|
|
self->clock_pin_number = clock->number;
|
|
claim_pin(clock);
|
|
|
|
if (mosi != (mcu_pin_obj_t*)&mp_const_none_obj) {
|
|
config.mosi_pin = mosi->number;
|
|
self->MOSI_pin_number = mosi->number;
|
|
claim_pin(mosi);
|
|
} else {
|
|
self->MOSI_pin_number = NO_PIN;
|
|
}
|
|
|
|
if (miso != (mcu_pin_obj_t*)&mp_const_none_obj) {
|
|
config.miso_pin = miso->number;
|
|
self->MISO_pin_number = mosi->number;
|
|
claim_pin(miso);
|
|
} else {
|
|
self->MISO_pin_number = NO_PIN;
|
|
}
|
|
|
|
nrfx_err_t err = nrfx_spim_init(&self->spim_peripheral->spim, &config, NULL, NULL);
|
|
|
|
// A soft reset doesn't uninit the driver so we might end up with a invalid state
|
|
if (err == NRFX_ERROR_INVALID_STATE) {
|
|
nrfx_spim_uninit(&self->spim_peripheral->spim);
|
|
err = nrfx_spim_init(&self->spim_peripheral->spim, &config, NULL, NULL);
|
|
}
|
|
|
|
if (err != NRFX_SUCCESS) {
|
|
common_hal_busio_spi_deinit(self);
|
|
mp_raise_OSError(MP_EIO);
|
|
}
|
|
}
|
|
|
|
bool common_hal_busio_spi_deinited(busio_spi_obj_t *self) {
|
|
return self->clock_pin_number == NO_PIN;
|
|
}
|
|
|
|
void common_hal_busio_spi_deinit(busio_spi_obj_t *self) {
|
|
if (common_hal_busio_spi_deinited(self))
|
|
return;
|
|
|
|
nrfx_spim_uninit(&self->spim_peripheral->spim);
|
|
|
|
reset_pin_number(self->clock_pin_number);
|
|
reset_pin_number(self->MOSI_pin_number);
|
|
reset_pin_number(self->MISO_pin_number);
|
|
}
|
|
|
|
bool common_hal_busio_spi_configure(busio_spi_obj_t *self, uint32_t baudrate, uint8_t polarity, uint8_t phase, uint8_t bits) {
|
|
// nrf52 does not support 16 bit
|
|
if (bits != 8) {
|
|
return false;
|
|
}
|
|
|
|
// Set desired frequency, rounding down, and don't go above available frequency for this SPIM.
|
|
nrf_spim_frequency_set(self->spim_peripheral->spim.p_reg,
|
|
baudrate_to_spim_frequency(MIN(baudrate,
|
|
self->spim_peripheral->max_frequency_MHz * 1000000)));
|
|
|
|
nrf_spim_mode_t mode = NRF_SPIM_MODE_0;
|
|
if (polarity) {
|
|
mode = (phase) ? NRF_SPIM_MODE_3 : NRF_SPIM_MODE_2;
|
|
} else {
|
|
mode = (phase) ? NRF_SPIM_MODE_1 : NRF_SPIM_MODE_0;
|
|
}
|
|
|
|
nrf_spim_configure(self->spim_peripheral->spim.p_reg, mode, NRF_SPIM_BIT_ORDER_MSB_FIRST);
|
|
|
|
return true;
|
|
}
|
|
|
|
bool common_hal_busio_spi_try_lock(busio_spi_obj_t *self) {
|
|
bool grabbed_lock = false;
|
|
// NRFX_CRITICAL_SECTION_ENTER();
|
|
if (!self->has_lock) {
|
|
grabbed_lock = true;
|
|
self->has_lock = true;
|
|
}
|
|
// NRFX_CRITICAL_SECTION_EXIT();
|
|
return grabbed_lock;
|
|
}
|
|
|
|
bool common_hal_busio_spi_has_lock(busio_spi_obj_t *self) {
|
|
return self->has_lock;
|
|
}
|
|
|
|
void common_hal_busio_spi_unlock(busio_spi_obj_t *self) {
|
|
self->has_lock = false;
|
|
}
|
|
|
|
bool common_hal_busio_spi_write(busio_spi_obj_t *self, const uint8_t *data, size_t len) {
|
|
if (len == 0)
|
|
return true;
|
|
|
|
const uint32_t max_xfer_size = self->spim_peripheral->max_xfer_size;
|
|
const uint32_t parts = len / max_xfer_size;
|
|
const uint32_t remainder = len % max_xfer_size;
|
|
|
|
for (uint32_t i = 0; i < parts; ++i) {
|
|
const nrfx_spim_xfer_desc_t xfer = NRFX_SPIM_XFER_TX(data + i * max_xfer_size, max_xfer_size);
|
|
if (nrfx_spim_xfer(&self->spim_peripheral->spim, &xfer, 0) != NRFX_SUCCESS)
|
|
return false;
|
|
}
|
|
|
|
if (remainder > 0) {
|
|
const nrfx_spim_xfer_desc_t xfer = NRFX_SPIM_XFER_TX(data + parts * max_xfer_size, remainder);
|
|
if (nrfx_spim_xfer(&self->spim_peripheral->spim, &xfer, 0) != NRFX_SUCCESS)
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool common_hal_busio_spi_read(busio_spi_obj_t *self, uint8_t *data, size_t len, uint8_t write_value) {
|
|
if (len == 0)
|
|
return true;
|
|
|
|
const uint32_t max_xfer_size = self->spim_peripheral->max_xfer_size;
|
|
const uint32_t parts = len / max_xfer_size;
|
|
const uint32_t remainder = len % max_xfer_size;
|
|
|
|
for (uint32_t i = 0; i < parts; ++i) {
|
|
const nrfx_spim_xfer_desc_t xfer = NRFX_SPIM_XFER_RX(data + i * max_xfer_size, max_xfer_size);
|
|
if (nrfx_spim_xfer(&self->spim_peripheral->spim, &xfer, 0) != NRFX_SUCCESS)
|
|
return false;
|
|
}
|
|
|
|
if (remainder > 0) {
|
|
const nrfx_spim_xfer_desc_t xfer = NRFX_SPIM_XFER_RX(data + parts * max_xfer_size, remainder);
|
|
if (nrfx_spim_xfer(&self->spim_peripheral->spim, &xfer, 0) != NRFX_SUCCESS)
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool common_hal_busio_spi_transfer(busio_spi_obj_t *self, uint8_t *data_out, uint8_t *data_in, size_t len) {
|
|
if (len == 0)
|
|
return true;
|
|
|
|
|
|
const uint32_t max_xfer_size = self->spim_peripheral->max_xfer_size;
|
|
const uint32_t parts = len / max_xfer_size;
|
|
const uint32_t remainder = len % max_xfer_size;
|
|
|
|
for (uint32_t i = 0; i < parts; ++i) {
|
|
const nrfx_spim_xfer_desc_t xfer = NRFX_SPIM_SINGLE_XFER(data_out + i * max_xfer_size, max_xfer_size,
|
|
data_in + i * max_xfer_size, max_xfer_size);
|
|
if (nrfx_spim_xfer(&self->spim_peripheral->spim, &xfer, 0) != NRFX_SUCCESS)
|
|
return false;
|
|
}
|
|
|
|
if (remainder > 0) {
|
|
const nrfx_spim_xfer_desc_t xfer = NRFX_SPIM_SINGLE_XFER(data_out + parts * max_xfer_size, remainder,
|
|
data_in + parts * max_xfer_size, remainder);
|
|
if (nrfx_spim_xfer(&self->spim_peripheral->spim, &xfer, 0) != NRFX_SUCCESS)
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
uint32_t common_hal_busio_spi_get_frequency(busio_spi_obj_t* self) {
|
|
switch (self->spim_peripheral->spim.p_reg->FREQUENCY) {
|
|
case NRF_SPIM_FREQ_125K:
|
|
return 125000;
|
|
case NRF_SPIM_FREQ_250K:
|
|
return 250000;
|
|
case NRF_SPIM_FREQ_500K:
|
|
return 500000;
|
|
case NRF_SPIM_FREQ_1M:
|
|
return 1000000;
|
|
case NRF_SPIM_FREQ_2M:
|
|
return 2000000;
|
|
case NRF_SPIM_FREQ_4M:
|
|
return 4000000;
|
|
case NRF_SPIM_FREQ_8M:
|
|
return 8000000;
|
|
#ifdef SPIM_FREQUENCY_FREQUENCY_M16
|
|
case NRF_SPIM_FREQ_16M:
|
|
return 16000000;
|
|
#endif
|
|
#ifdef SPIM_FREQUENCY_FREQUENCY_M32
|
|
case NRF_SPIM_FREQ_32M:
|
|
return 32000000;
|
|
#endif
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
uint8_t common_hal_busio_spi_get_phase(busio_spi_obj_t* self) {
|
|
return 0;
|
|
}
|
|
|
|
uint8_t common_hal_busio_spi_get_polarity(busio_spi_obj_t* self) {
|
|
return 0;
|
|
}
|