ports/esp32/machine_hw_spi.c - lite/micropython - Linaro Git Browser

 /*
  * This file is part of the MicroPython project, http://micropython.org/
  *
  * The MIT License (MIT)
  *
  * Copyright (c) 2017 "Eric Poulsen" <eric@zyxod.com>
  *
  * 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 <stdio.h>
 #include <stdint.h>
 #include <string.h>

 #include "py/runtime.h"
 #include "py/stream.h"
 #include "py/mphal.h"
 #include "extmod/modmachine.h"

 #include "driver/spi_master.h"
 #include "soc/gpio_sig_map.h"
 #include "soc/spi_pins.h"

 // SPI mappings by device, naming used by IDF old/new
 // upython   | ESP32     | ESP32S2   | ESP32S3 | ESP32C3 | ESP32C6
 // ----------+-----------+-----------+---------+---------+---------
 // SPI(id=1) | HSPI/SPI2 | FSPI/SPI2 | SPI2    | SPI2    | SPI2
 // SPI(id=2) | VSPI/SPI3 | HSPI/SPI3 | SPI3    | err     | err

 // Number of available hardware SPI peripherals.
 #if SOC_SPI_PERIPH_NUM > 2
 #define MICROPY_HW_SPI_MAX (2)
 #else
 #define MICROPY_HW_SPI_MAX (1)
 #endif

 // Default pins for SPI(id=1) aka IDF SPI2, can be overridden by a board
 #ifndef MICROPY_HW_SPI1_SCK
 // Use IO_MUX pins by default.
 // If SPI lines are routed to other pins through GPIO matrix
 // routing adds some delay and lower limit applies to SPI clk freq
 #define MICROPY_HW_SPI1_SCK SPI2_IOMUX_PIN_NUM_CLK
 #define MICROPY_HW_SPI1_MOSI SPI2_IOMUX_PIN_NUM_MOSI
 #define MICROPY_HW_SPI1_MISO SPI2_IOMUX_PIN_NUM_MISO
 #endif

 // Default pins for SPI(id=2) aka IDF SPI3, can be overridden by a board
 #ifndef MICROPY_HW_SPI2_SCK
 #if CONFIG_IDF_TARGET_ESP32
 // ESP32 has IO_MUX pins for VSPI/SPI3 lines, use them as defaults
 #define MICROPY_HW_SPI2_SCK SPI3_IOMUX_PIN_NUM_CLK      // pin 18
 #define MICROPY_HW_SPI2_MOSI SPI3_IOMUX_PIN_NUM_MOSI    // pin 23
 #define MICROPY_HW_SPI2_MISO SPI3_IOMUX_PIN_NUM_MISO    // pin 19
 #elif CONFIG_IDF_TARGET_ESP32S2 || CONFIG_IDF_TARGET_ESP32S3
 // ESP32S2 and S3 uses GPIO matrix for SPI3 pins, no IO_MUX possible
 // Set defaults to the pins used by SPI2 in Octal mode
 #define MICROPY_HW_SPI2_SCK (36)
 #define MICROPY_HW_SPI2_MOSI (35)
 #define MICROPY_HW_SPI2_MISO (37)
 #endif
 #endif

 #define MP_HW_SPI_MAX_XFER_BYTES (4092)
 #define MP_HW_SPI_MAX_XFER_BITS (MP_HW_SPI_MAX_XFER_BYTES * 8) // Has to be an even multiple of 8

 typedef struct _machine_hw_spi_default_pins_t {
     union {
         int8_t array[3];
         struct {
             // Must be in enum's ARG_sck, ARG_mosi, ARG_miso, etc. order
             int8_t sck;
             int8_t mosi;
             int8_t miso;
         } pins;
     };
 } machine_hw_spi_default_pins_t;

 typedef struct _machine_hw_spi_obj_t {
     mp_obj_base_t base;
     spi_host_device_t host;
     uint32_t baudrate;
     uint8_t polarity;
     uint8_t phase;
     uint8_t bits;
     uint8_t firstbit;
     int8_t sck;
     int8_t mosi;
     int8_t miso;
     spi_device_handle_t spi;
     enum {
         MACHINE_HW_SPI_STATE_NONE,
         MACHINE_HW_SPI_STATE_INIT,
         MACHINE_HW_SPI_STATE_DEINIT
     } state;
 } machine_hw_spi_obj_t;

 // Default pin mappings for the hardware SPI instances
 static const machine_hw_spi_default_pins_t machine_hw_spi_default_pins[MICROPY_HW_SPI_MAX] = {
     { .pins = { .sck = MICROPY_HW_SPI1_SCK, .mosi = MICROPY_HW_SPI1_MOSI, .miso = MICROPY_HW_SPI1_MISO }},
     #ifdef MICROPY_HW_SPI2_SCK
     { .pins = { .sck = MICROPY_HW_SPI2_SCK, .mosi = MICROPY_HW_SPI2_MOSI, .miso = MICROPY_HW_SPI2_MISO }},
     #endif
 };

 // Common arguments for init() and make new
 enum { ARG_id, ARG_baudrate, ARG_polarity, ARG_phase, ARG_bits, ARG_firstbit, ARG_sck, ARG_mosi, ARG_miso };
 static const mp_arg_t spi_allowed_args[] = {
     { MP_QSTR_id,       MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = -1} },
     { MP_QSTR_baudrate, MP_ARG_INT, {.u_int = -1} },
     { MP_QSTR_polarity, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1} },
     { MP_QSTR_phase,    MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1} },
     { MP_QSTR_bits,     MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1} },
     { MP_QSTR_firstbit, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = -1} },
     { MP_QSTR_sck,      MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
     { MP_QSTR_mosi,     MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
     { MP_QSTR_miso,     MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
 };

 // Static objects mapping to SPI2 (and SPI3 if available) hardware peripherals.
 static machine_hw_spi_obj_t machine_hw_spi_obj[MICROPY_HW_SPI_MAX];

 static void machine_hw_spi_deinit_internal(machine_hw_spi_obj_t *self) {
     switch (spi_bus_remove_device(self->spi)) {
         case ESP_ERR_INVALID_ARG:
             mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("invalid configuration"));
             return;

         case ESP_ERR_INVALID_STATE:
             mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("SPI device already freed"));
             return;
     }

     switch (spi_bus_free(self->host)) {
         case ESP_ERR_INVALID_ARG:
             mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("invalid configuration"));
             return;

         case ESP_ERR_INVALID_STATE:
             mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("SPI bus already freed"));
             return;
     }

     int8_t pins[3] = {self->miso, self->mosi, self->sck};

     for (int i = 0; i < 3; i++) {
         if (pins[i] != -1) {
             esp_rom_gpio_pad_select_gpio(pins[i]);
             esp_rom_gpio_connect_out_signal(pins[i], SIG_GPIO_OUT_IDX, false, false);
             gpio_set_direction(pins[i], GPIO_MODE_INPUT);
         }
     }
 }

 static void machine_hw_spi_init_internal(machine_hw_spi_obj_t *self, mp_arg_val_t args[]) {

     // if we're not initialized, then we're
     // implicitly 'changed', since this is the init routine
     bool changed = self->state != MACHINE_HW_SPI_STATE_INIT;

     esp_err_t ret;

     machine_hw_spi_obj_t old_self = *self;

     if (args[ARG_baudrate].u_int != -1) {
         // calculate the actual clock frequency that the SPI peripheral can produce
         uint32_t baudrate = spi_get_actual_clock(APB_CLK_FREQ, args[ARG_baudrate].u_int, 0);
         if (baudrate != self->baudrate) {
             self->baudrate = baudrate;
             changed = true;
         }
     }

     if (args[ARG_polarity].u_int != -1 && args[ARG_polarity].u_int != self->polarity) {
         self->polarity = args[ARG_polarity].u_int;
         changed = true;
     }

     if (args[ARG_phase].u_int != -1 && args[ARG_phase].u_int != self->phase) {
         self->phase = args[ARG_phase].u_int;
         changed = true;
     }

     if (args[ARG_bits].u_int != -1 && args[ARG_bits].u_int <= 0) {
         mp_raise_ValueError(MP_ERROR_TEXT("invalid bits"));
     }

     if (args[ARG_bits].u_int != -1 && args[ARG_bits].u_int != self->bits) {
         self->bits = args[ARG_bits].u_int;
         changed = true;
     }

     if (args[ARG_firstbit].u_int != -1 && args[ARG_firstbit].u_int != self->firstbit) {
         self->firstbit = args[ARG_firstbit].u_int;
         changed = true;
     }

     if (args[ARG_sck].u_int != -2 && args[ARG_sck].u_int != self->sck) {
         self->sck = args[ARG_sck].u_int;
         changed = true;
     }

     if (args[ARG_mosi].u_int != -2 && args[ARG_mosi].u_int != self->mosi) {
         self->mosi = args[ARG_mosi].u_int;
         changed = true;
     }

     if (args[ARG_miso].u_int != -2 && args[ARG_miso].u_int != self->miso) {
         self->miso = args[ARG_miso].u_int;
         changed = true;
     }

     if (changed) {
         if (self->state == MACHINE_HW_SPI_STATE_INIT) {
             self->state = MACHINE_HW_SPI_STATE_DEINIT;
             machine_hw_spi_deinit_internal(&old_self);
         }
     } else {
         return; // no changes
     }

     spi_bus_config_t buscfg = {
         .miso_io_num = self->miso,
         .mosi_io_num = self->mosi,
         .sclk_io_num = self->sck,
         .quadwp_io_num = -1,
         .quadhd_io_num = -1
     };

     spi_device_interface_config_t devcfg = {
         .clock_speed_hz = self->baudrate,
         .mode = self->phase | (self->polarity << 1),
         .spics_io_num = -1, // No CS pin
         .queue_size = 2,
         .flags = self->firstbit == MICROPY_PY_MACHINE_SPI_LSB ? SPI_DEVICE_TXBIT_LSBFIRST | SPI_DEVICE_RXBIT_LSBFIRST : 0,
         .pre_cb = NULL
     };

     // Initialize the SPI bus

     // Select DMA channel based on the hardware SPI host
     int dma_chan = 0;
     #if CONFIG_IDF_TARGET_ESP32
     if (self->host == SPI2_HOST) {
         dma_chan = 1;
     } else {
         dma_chan = 2;
     }
     #else
     dma_chan = SPI_DMA_CH_AUTO;
     #endif

     ret = spi_bus_initialize(self->host, &buscfg, dma_chan);
     switch (ret) {
         case ESP_ERR_INVALID_ARG:
             mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("invalid configuration"));
             return;

         case ESP_ERR_INVALID_STATE:
             mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("SPI host already in use"));
             return;
     }

     ret = spi_bus_add_device(self->host, &devcfg, &self->spi);
     switch (ret) {
         case ESP_ERR_INVALID_ARG:
             mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("invalid configuration"));
             spi_bus_free(self->host);
             return;

         case ESP_ERR_NO_MEM:
             mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("out of memory"));
             spi_bus_free(self->host);
             return;

         case ESP_ERR_NOT_FOUND:
             mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("no free slots"));
             spi_bus_free(self->host);
             return;
     }
     self->state = MACHINE_HW_SPI_STATE_INIT;
 }

 static void machine_hw_spi_deinit(mp_obj_base_t *self_in) {
     machine_hw_spi_obj_t *self = (machine_hw_spi_obj_t *)self_in;
     if (self->state == MACHINE_HW_SPI_STATE_INIT) {
         self->state = MACHINE_HW_SPI_STATE_DEINIT;
         machine_hw_spi_deinit_internal(self);
     }
 }

 static mp_uint_t gcd(mp_uint_t x, mp_uint_t y) {
     while (x != y) {
         if (x > y) {
             x -= y;
         } else {
             y -= x;
         }
     }
     return x;
 }

 static void machine_hw_spi_transfer(mp_obj_base_t *self_in, size_t len, const uint8_t *src, uint8_t *dest) {
     machine_hw_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);

     if (self->state == MACHINE_HW_SPI_STATE_DEINIT) {
         mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("transfer on deinitialized SPI"));
         return;
     }

     // Round to nearest whole set of bits
     int bits_to_send = len * 8 / self->bits * self->bits;

     if (!bits_to_send) {
         mp_raise_ValueError(MP_ERROR_TEXT("buffer too short"));
     }

     if (len <= 4) {
         spi_transaction_t transaction = { 0 };

         if (src != NULL) {
             memcpy(&transaction.tx_data, src, len);
         }

         transaction.flags = SPI_TRANS_USE_TXDATA | SPI_TRANS_USE_RXDATA;
         transaction.length = bits_to_send;
         spi_device_transmit(self->spi, &transaction);

         if (dest != NULL) {
             memcpy(dest, &transaction.rx_data, len);
         }
     } else {
         int offset = 0;
         int bits_remaining = bits_to_send;
         int optimum_word_size = 8 * self->bits / gcd(8, self->bits);
         int max_transaction_bits = MP_HW_SPI_MAX_XFER_BITS / optimum_word_size * optimum_word_size;
         spi_transaction_t *transaction, *result, transactions[2];
         int i = 0;

         spi_device_acquire_bus(self->spi, portMAX_DELAY);

         while (bits_remaining) {
             transaction = transactions + i++ % 2;
             memset(transaction, 0, sizeof(spi_transaction_t));

             transaction->length =
                 bits_remaining > max_transaction_bits ? max_transaction_bits : bits_remaining;

             if (src != NULL) {
                 transaction->tx_buffer = src + offset;
             }
             if (dest != NULL) {
                 transaction->rx_buffer = dest + offset;
             }

             spi_device_queue_trans(self->spi, transaction, portMAX_DELAY);
             bits_remaining -= transaction->length;

             if (offset > 0) {
                 // wait for previously queued transaction
                 MP_THREAD_GIL_EXIT();
                 spi_device_get_trans_result(self->spi, &result, portMAX_DELAY);
                 MP_THREAD_GIL_ENTER();
             }

             // doesn't need ceil(); loop ends when bits_remaining is 0
             offset += transaction->length / 8;
         }

         // wait for last transaction
         MP_THREAD_GIL_EXIT();
         spi_device_get_trans_result(self->spi, &result, portMAX_DELAY);
         MP_THREAD_GIL_ENTER();
         spi_device_release_bus(self->spi);
     }
 }

 /******************************************************************************/
 // MicroPython bindings for hw_spi

 static void machine_hw_spi_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
     machine_hw_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);
     mp_printf(print, "SPI(id=%u, baudrate=%u, polarity=%u, phase=%u, bits=%u, firstbit=%u, sck=%d, mosi=%d, miso=%d)",
         self->host, self->baudrate, self->polarity,
         self->phase, self->bits, self->firstbit,
         self->sck, self->mosi, self->miso);
 }

 // Take an arg list made from spi_allowed_args, and put in default or "keep same" values
 // into all the u_int fields.
 // The behavior is slightly different for a new call vs an init method on an existing object.
 // Unspecified arguments for new will use defaults, for init they keep the existing value.
 static void machine_hw_spi_argcheck(mp_arg_val_t args[], const machine_hw_spi_default_pins_t *default_pins) {
 // A non-NULL default_pins argument will trigger the "use default" behavior.
     // Replace pin args with default/current values for new vs init call, respectively
     for (int i = ARG_sck; i <= ARG_miso; i++) {
         if (args[i].u_obj == MP_OBJ_NULL) {
             args[i].u_int = default_pins ? default_pins->array[i - ARG_sck] : -2;
         } else if (args[i].u_obj == mp_const_none) {
             args[i].u_int = -1;
         } else {
             args[i].u_int = machine_pin_get_id(args[i].u_obj);
         }
     }
 }

 static void machine_hw_spi_init(mp_obj_base_t *self_in, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
     machine_hw_spi_obj_t *self = (machine_hw_spi_obj_t *)self_in;

     mp_arg_val_t args[MP_ARRAY_SIZE(spi_allowed_args)];
     // offset arg lists by 1 to skip first arg, id, which is not valid for init()
     mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(spi_allowed_args) - 1,
         spi_allowed_args + 1, args + 1);

     machine_hw_spi_argcheck(args, NULL);
     machine_hw_spi_init_internal(self, args);
 }

 mp_obj_t machine_hw_spi_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
     MP_MACHINE_SPI_CHECK_FOR_LEGACY_SOFTSPI_CONSTRUCTION(n_args, n_kw, all_args);

     mp_arg_val_t args[MP_ARRAY_SIZE(spi_allowed_args)];
     mp_arg_parse_all_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(spi_allowed_args), spi_allowed_args, args);

     const mp_int_t spi_id = args[ARG_id].u_int;
     if (1 <= spi_id && spi_id <= MICROPY_HW_SPI_MAX) {
         machine_hw_spi_argcheck(args, &machine_hw_spi_default_pins[spi_id - 1]);
     } else {
         mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("SPI(%d) doesn't exist"), spi_id);
     }
     // Replace -1 non-pin args with default values
     static const mp_int_t defaults[] = { 500000, 0, 0, 8, MICROPY_PY_MACHINE_SPI_MSB };
     for (int i = ARG_baudrate; i <= ARG_firstbit; i++) {
         if (args[i].u_int == -1) {
             args[i].u_int = defaults[i - ARG_baudrate];
         }
     }

     machine_hw_spi_obj_t *self = &machine_hw_spi_obj[spi_id - 1];
     self->host = spi_id;

     self->base.type = &machine_spi_type;

     machine_hw_spi_init_internal(self, args);

     return MP_OBJ_FROM_PTR(self);
 }

 spi_host_device_t machine_hw_spi_get_host(mp_obj_t in) {
     if (mp_obj_get_type(in) != &machine_spi_type) {
         mp_raise_ValueError(MP_ERROR_TEXT("expecting a SPI object"));
     }
     machine_hw_spi_obj_t *self = (machine_hw_spi_obj_t *)in;
     return self->host;
 }

 static const mp_machine_spi_p_t machine_hw_spi_p = {
     .init = machine_hw_spi_init,
     .deinit = machine_hw_spi_deinit,
     .transfer = machine_hw_spi_transfer,
 };

 MP_DEFINE_CONST_OBJ_TYPE(
     machine_spi_type,
     MP_QSTR_SPI,
     MP_TYPE_FLAG_NONE,
     make_new, machine_hw_spi_make_new,
     print, machine_hw_spi_print,
     protocol, &machine_hw_spi_p,
     locals_dict, &mp_machine_spi_locals_dict
     );
	/*
	* This file is part of the MicroPython project, http://micropython.org/
	*
	* The MIT License (MIT)
	*
	* Copyright (c) 2017 "Eric Poulsen" <eric@zyxod.com>
	*
	* 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 <stdio.h>
	#include <stdint.h>
	#include <string.h>

	#include "py/runtime.h"
	#include "py/stream.h"
	#include "py/mphal.h"
	#include "extmod/modmachine.h"

	#include "driver/spi_master.h"
	#include "soc/gpio_sig_map.h"
	#include "soc/spi_pins.h"

	// SPI mappings by device, naming used by IDF old/new
	// upython \| ESP32 \| ESP32S2 \| ESP32S3 \| ESP32C3 \| ESP32C6
	// ----------+-----------+-----------+---------+---------+---------
	// SPI(id=1) \| HSPI/SPI2 \| FSPI/SPI2 \| SPI2 \| SPI2 \| SPI2
	// SPI(id=2) \| VSPI/SPI3 \| HSPI/SPI3 \| SPI3 \| err \| err

	// Number of available hardware SPI peripherals.
	#if SOC_SPI_PERIPH_NUM > 2
	#define MICROPY_HW_SPI_MAX (2)
	#else
	#define MICROPY_HW_SPI_MAX (1)
	#endif

	// Default pins for SPI(id=1) aka IDF SPI2, can be overridden by a board
	#ifndef MICROPY_HW_SPI1_SCK
	// Use IO_MUX pins by default.
	// If SPI lines are routed to other pins through GPIO matrix
	// routing adds some delay and lower limit applies to SPI clk freq
	#define MICROPY_HW_SPI1_SCK SPI2_IOMUX_PIN_NUM_CLK
	#define MICROPY_HW_SPI1_MOSI SPI2_IOMUX_PIN_NUM_MOSI
	#define MICROPY_HW_SPI1_MISO SPI2_IOMUX_PIN_NUM_MISO
	#endif

	// Default pins for SPI(id=2) aka IDF SPI3, can be overridden by a board
	#ifndef MICROPY_HW_SPI2_SCK
	#if CONFIG_IDF_TARGET_ESP32
	// ESP32 has IO_MUX pins for VSPI/SPI3 lines, use them as defaults
	#define MICROPY_HW_SPI2_SCK SPI3_IOMUX_PIN_NUM_CLK // pin 18
	#define MICROPY_HW_SPI2_MOSI SPI3_IOMUX_PIN_NUM_MOSI // pin 23
	#define MICROPY_HW_SPI2_MISO SPI3_IOMUX_PIN_NUM_MISO // pin 19
	#elif CONFIG_IDF_TARGET_ESP32S2 \|\| CONFIG_IDF_TARGET_ESP32S3
	// ESP32S2 and S3 uses GPIO matrix for SPI3 pins, no IO_MUX possible
	// Set defaults to the pins used by SPI2 in Octal mode
	#define MICROPY_HW_SPI2_SCK (36)
	#define MICROPY_HW_SPI2_MOSI (35)
	#define MICROPY_HW_SPI2_MISO (37)
	#endif
	#endif

	#define MP_HW_SPI_MAX_XFER_BYTES (4092)
	#define MP_HW_SPI_MAX_XFER_BITS (MP_HW_SPI_MAX_XFER_BYTES * 8) // Has to be an even multiple of 8

	typedef struct _machine_hw_spi_default_pins_t {
	union {
	int8_t array[3];
	struct {
	// Must be in enum's ARG_sck, ARG_mosi, ARG_miso, etc. order
	int8_t sck;
	int8_t mosi;
	int8_t miso;
	} pins;
	};
	} machine_hw_spi_default_pins_t;

	typedef struct _machine_hw_spi_obj_t {
	mp_obj_base_t base;
	spi_host_device_t host;
	uint32_t baudrate;
	uint8_t polarity;
	uint8_t phase;
	uint8_t bits;
	uint8_t firstbit;
	int8_t sck;
	int8_t mosi;
	int8_t miso;
	spi_device_handle_t spi;
	enum {
	MACHINE_HW_SPI_STATE_NONE,
	MACHINE_HW_SPI_STATE_INIT,
	MACHINE_HW_SPI_STATE_DEINIT
	} state;
	} machine_hw_spi_obj_t;

	// Default pin mappings for the hardware SPI instances
	static const machine_hw_spi_default_pins_t machine_hw_spi_default_pins[MICROPY_HW_SPI_MAX] = {
	{ .pins = { .sck = MICROPY_HW_SPI1_SCK, .mosi = MICROPY_HW_SPI1_MOSI, .miso = MICROPY_HW_SPI1_MISO }},
	#ifdef MICROPY_HW_SPI2_SCK
	{ .pins = { .sck = MICROPY_HW_SPI2_SCK, .mosi = MICROPY_HW_SPI2_MOSI, .miso = MICROPY_HW_SPI2_MISO }},
	#endif
	};

	// Common arguments for init() and make new
	enum { ARG_id, ARG_baudrate, ARG_polarity, ARG_phase, ARG_bits, ARG_firstbit, ARG_sck, ARG_mosi, ARG_miso };
	static const mp_arg_t spi_allowed_args[] = {
	{ MP_QSTR_id, MP_ARG_REQUIRED \| MP_ARG_INT, {.u_int = -1} },
	{ MP_QSTR_baudrate, MP_ARG_INT, {.u_int = -1} },
	{ MP_QSTR_polarity, MP_ARG_KW_ONLY \| MP_ARG_INT, {.u_int = -1} },
	{ MP_QSTR_phase, MP_ARG_KW_ONLY \| MP_ARG_INT, {.u_int = -1} },
	{ MP_QSTR_bits, MP_ARG_KW_ONLY \| MP_ARG_INT, {.u_int = -1} },
	{ MP_QSTR_firstbit, MP_ARG_KW_ONLY \| MP_ARG_INT, {.u_int = -1} },
	{ MP_QSTR_sck, MP_ARG_KW_ONLY \| MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
	{ MP_QSTR_mosi, MP_ARG_KW_ONLY \| MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
	{ MP_QSTR_miso, MP_ARG_KW_ONLY \| MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
	};

	// Static objects mapping to SPI2 (and SPI3 if available) hardware peripherals.
	static machine_hw_spi_obj_t machine_hw_spi_obj[MICROPY_HW_SPI_MAX];

	static void machine_hw_spi_deinit_internal(machine_hw_spi_obj_t *self) {
	switch (spi_bus_remove_device(self->spi)) {
	case ESP_ERR_INVALID_ARG:
	mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("invalid configuration"));
	return;

	case ESP_ERR_INVALID_STATE:
	mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("SPI device already freed"));
	return;
	}

	switch (spi_bus_free(self->host)) {
	case ESP_ERR_INVALID_ARG:
	mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("invalid configuration"));
	return;

	case ESP_ERR_INVALID_STATE:
	mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("SPI bus already freed"));
	return;
	}

	int8_t pins[3] = {self->miso, self->mosi, self->sck};

	for (int i = 0; i < 3; i++) {
	if (pins[i] != -1) {
	esp_rom_gpio_pad_select_gpio(pins[i]);
	esp_rom_gpio_connect_out_signal(pins[i], SIG_GPIO_OUT_IDX, false, false);
	gpio_set_direction(pins[i], GPIO_MODE_INPUT);
	}
	}
	}

	static void machine_hw_spi_init_internal(machine_hw_spi_obj_t *self, mp_arg_val_t args[]) {

	// if we're not initialized, then we're
	// implicitly 'changed', since this is the init routine
	bool changed = self->state != MACHINE_HW_SPI_STATE_INIT;

	esp_err_t ret;

	machine_hw_spi_obj_t old_self = *self;

	if (args[ARG_baudrate].u_int != -1) {
	// calculate the actual clock frequency that the SPI peripheral can produce
	uint32_t baudrate = spi_get_actual_clock(APB_CLK_FREQ, args[ARG_baudrate].u_int, 0);
	if (baudrate != self->baudrate) {
	self->baudrate = baudrate;
	changed = true;
	}
	}

	if (args[ARG_polarity].u_int != -1 && args[ARG_polarity].u_int != self->polarity) {
	self->polarity = args[ARG_polarity].u_int;
	changed = true;
	}

	if (args[ARG_phase].u_int != -1 && args[ARG_phase].u_int != self->phase) {
	self->phase = args[ARG_phase].u_int;
	changed = true;
	}

	if (args[ARG_bits].u_int != -1 && args[ARG_bits].u_int <= 0) {
	mp_raise_ValueError(MP_ERROR_TEXT("invalid bits"));
	}

	if (args[ARG_bits].u_int != -1 && args[ARG_bits].u_int != self->bits) {
	self->bits = args[ARG_bits].u_int;
	changed = true;
	}

	if (args[ARG_firstbit].u_int != -1 && args[ARG_firstbit].u_int != self->firstbit) {
	self->firstbit = args[ARG_firstbit].u_int;
	changed = true;
	}

	if (args[ARG_sck].u_int != -2 && args[ARG_sck].u_int != self->sck) {
	self->sck = args[ARG_sck].u_int;
	changed = true;
	}

	if (args[ARG_mosi].u_int != -2 && args[ARG_mosi].u_int != self->mosi) {
	self->mosi = args[ARG_mosi].u_int;
	changed = true;
	}

	if (args[ARG_miso].u_int != -2 && args[ARG_miso].u_int != self->miso) {
	self->miso = args[ARG_miso].u_int;
	changed = true;
	}

	if (changed) {
	if (self->state == MACHINE_HW_SPI_STATE_INIT) {
	self->state = MACHINE_HW_SPI_STATE_DEINIT;
	machine_hw_spi_deinit_internal(&old_self);
	}
	} else {
	return; // no changes
	}

	spi_bus_config_t buscfg = {
	.miso_io_num = self->miso,
	.mosi_io_num = self->mosi,
	.sclk_io_num = self->sck,
	.quadwp_io_num = -1,
	.quadhd_io_num = -1
	};

	spi_device_interface_config_t devcfg = {
	.clock_speed_hz = self->baudrate,
	.mode = self->phase \| (self->polarity << 1),
	.spics_io_num = -1, // No CS pin
	.queue_size = 2,
	.flags = self->firstbit == MICROPY_PY_MACHINE_SPI_LSB ? SPI_DEVICE_TXBIT_LSBFIRST \| SPI_DEVICE_RXBIT_LSBFIRST : 0,
	.pre_cb = NULL
	};

	// Initialize the SPI bus

	// Select DMA channel based on the hardware SPI host
	int dma_chan = 0;
	#if CONFIG_IDF_TARGET_ESP32
	if (self->host == SPI2_HOST) {
	dma_chan = 1;
	} else {
	dma_chan = 2;
	}
	#else
	dma_chan = SPI_DMA_CH_AUTO;
	#endif

	ret = spi_bus_initialize(self->host, &buscfg, dma_chan);
	switch (ret) {
	case ESP_ERR_INVALID_ARG:
	mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("invalid configuration"));
	return;

	case ESP_ERR_INVALID_STATE:
	mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("SPI host already in use"));
	return;
	}

	ret = spi_bus_add_device(self->host, &devcfg, &self->spi);
	switch (ret) {
	case ESP_ERR_INVALID_ARG:
	mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("invalid configuration"));
	spi_bus_free(self->host);
	return;

	case ESP_ERR_NO_MEM:
	mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("out of memory"));
	spi_bus_free(self->host);
	return;

	case ESP_ERR_NOT_FOUND:
	mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("no free slots"));
	spi_bus_free(self->host);
	return;
	}
	self->state = MACHINE_HW_SPI_STATE_INIT;
	}

	static void machine_hw_spi_deinit(mp_obj_base_t *self_in) {
	machine_hw_spi_obj_t self = (machine_hw_spi_obj_t )self_in;
	if (self->state == MACHINE_HW_SPI_STATE_INIT) {
	self->state = MACHINE_HW_SPI_STATE_DEINIT;
	machine_hw_spi_deinit_internal(self);
	}
	}

	static mp_uint_t gcd(mp_uint_t x, mp_uint_t y) {
	while (x != y) {
	if (x > y) {
	x -= y;
	} else {
	y -= x;
	}
	}
	return x;
	}

	static void machine_hw_spi_transfer(mp_obj_base_t self_in, size_t len, const uint8_t src, uint8_t *dest) {
	machine_hw_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);

	if (self->state == MACHINE_HW_SPI_STATE_DEINIT) {
	mp_raise_msg(&mp_type_OSError, MP_ERROR_TEXT("transfer on deinitialized SPI"));
	return;
	}

	// Round to nearest whole set of bits
	int bits_to_send = len * 8 / self->bits * self->bits;

	if (!bits_to_send) {
	mp_raise_ValueError(MP_ERROR_TEXT("buffer too short"));
	}

	if (len <= 4) {
	spi_transaction_t transaction = { 0 };

	if (src != NULL) {
	memcpy(&transaction.tx_data, src, len);
	}

	transaction.flags = SPI_TRANS_USE_TXDATA \| SPI_TRANS_USE_RXDATA;
	transaction.length = bits_to_send;
	spi_device_transmit(self->spi, &transaction);

	if (dest != NULL) {
	memcpy(dest, &transaction.rx_data, len);
	}
	} else {
	int offset = 0;
	int bits_remaining = bits_to_send;
	int optimum_word_size = 8 * self->bits / gcd(8, self->bits);
	int max_transaction_bits = MP_HW_SPI_MAX_XFER_BITS / optimum_word_size * optimum_word_size;
	spi_transaction_t transaction, result, transactions[2];
	int i = 0;

	spi_device_acquire_bus(self->spi, portMAX_DELAY);

	while (bits_remaining) {
	transaction = transactions + i++ % 2;
	memset(transaction, 0, sizeof(spi_transaction_t));

	transaction->length =
	bits_remaining > max_transaction_bits ? max_transaction_bits : bits_remaining;

	if (src != NULL) {
	transaction->tx_buffer = src + offset;
	}
	if (dest != NULL) {
	transaction->rx_buffer = dest + offset;
	}

	spi_device_queue_trans(self->spi, transaction, portMAX_DELAY);
	bits_remaining -= transaction->length;

	if (offset > 0) {
	// wait for previously queued transaction
	MP_THREAD_GIL_EXIT();
	spi_device_get_trans_result(self->spi, &result, portMAX_DELAY);
	MP_THREAD_GIL_ENTER();
	}

	// doesn't need ceil(); loop ends when bits_remaining is 0
	offset += transaction->length / 8;
	}

	// wait for last transaction
	MP_THREAD_GIL_EXIT();
	spi_device_get_trans_result(self->spi, &result, portMAX_DELAY);
	MP_THREAD_GIL_ENTER();
	spi_device_release_bus(self->spi);
	}
	}

	/******************************************************************************/
	// MicroPython bindings for hw_spi

	static void machine_hw_spi_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
	machine_hw_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);
	mp_printf(print, "SPI(id=%u, baudrate=%u, polarity=%u, phase=%u, bits=%u, firstbit=%u, sck=%d, mosi=%d, miso=%d)",
	self->host, self->baudrate, self->polarity,
	self->phase, self->bits, self->firstbit,
	self->sck, self->mosi, self->miso);
	}

	// Take an arg list made from spi_allowed_args, and put in default or "keep same" values
	// into all the u_int fields.
	// The behavior is slightly different for a new call vs an init method on an existing object.
	// Unspecified arguments for new will use defaults, for init they keep the existing value.
	static void machine_hw_spi_argcheck(mp_arg_val_t args[], const machine_hw_spi_default_pins_t *default_pins) {
	// A non-NULL default_pins argument will trigger the "use default" behavior.
	// Replace pin args with default/current values for new vs init call, respectively
	for (int i = ARG_sck; i <= ARG_miso; i++) {
	if (args[i].u_obj == MP_OBJ_NULL) {
	args[i].u_int = default_pins ? default_pins->array[i - ARG_sck] : -2;
	} else if (args[i].u_obj == mp_const_none) {
	args[i].u_int = -1;
	} else {
	args[i].u_int = machine_pin_get_id(args[i].u_obj);
	}
	}
	}

	static void machine_hw_spi_init(mp_obj_base_t self_in, size_t n_args, const mp_obj_t pos_args, mp_map_t *kw_args) {
	machine_hw_spi_obj_t self = (machine_hw_spi_obj_t )self_in;

	mp_arg_val_t args[MP_ARRAY_SIZE(spi_allowed_args)];
	// offset arg lists by 1 to skip first arg, id, which is not valid for init()
	mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(spi_allowed_args) - 1,
	spi_allowed_args + 1, args + 1);

	machine_hw_spi_argcheck(args, NULL);
	machine_hw_spi_init_internal(self, args);
	}

	mp_obj_t machine_hw_spi_make_new(const mp_obj_type_t type, size_t n_args, size_t n_kw, const mp_obj_t all_args) {
	MP_MACHINE_SPI_CHECK_FOR_LEGACY_SOFTSPI_CONSTRUCTION(n_args, n_kw, all_args);

	mp_arg_val_t args[MP_ARRAY_SIZE(spi_allowed_args)];
	mp_arg_parse_all_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(spi_allowed_args), spi_allowed_args, args);

	const mp_int_t spi_id = args[ARG_id].u_int;
	if (1 <= spi_id && spi_id <= MICROPY_HW_SPI_MAX) {
	machine_hw_spi_argcheck(args, &machine_hw_spi_default_pins[spi_id - 1]);
	} else {
	mp_raise_msg_varg(&mp_type_ValueError, MP_ERROR_TEXT("SPI(%d) doesn't exist"), spi_id);
	}
	// Replace -1 non-pin args with default values
	static const mp_int_t defaults[] = { 500000, 0, 0, 8, MICROPY_PY_MACHINE_SPI_MSB };
	for (int i = ARG_baudrate; i <= ARG_firstbit; i++) {
	if (args[i].u_int == -1) {
	args[i].u_int = defaults[i - ARG_baudrate];
	}
	}

	machine_hw_spi_obj_t *self = &machine_hw_spi_obj[spi_id - 1];
	self->host = spi_id;

	self->base.type = &machine_spi_type;

	machine_hw_spi_init_internal(self, args);

	return MP_OBJ_FROM_PTR(self);
	}

	spi_host_device_t machine_hw_spi_get_host(mp_obj_t in) {
	if (mp_obj_get_type(in) != &machine_spi_type) {
	mp_raise_ValueError(MP_ERROR_TEXT("expecting a SPI object"));
	}
	machine_hw_spi_obj_t self = (machine_hw_spi_obj_t )in;
	return self->host;
	}

	static const mp_machine_spi_p_t machine_hw_spi_p = {
	.init = machine_hw_spi_init,
	.deinit = machine_hw_spi_deinit,
	.transfer = machine_hw_spi_transfer,
	};

	MP_DEFINE_CONST_OBJ_TYPE(
	machine_spi_type,
	MP_QSTR_SPI,
	MP_TYPE_FLAG_NONE,
	make_new, machine_hw_spi_make_new,
	print, machine_hw_spi_print,
	protocol, &machine_hw_spi_p,
	locals_dict, &mp_machine_spi_locals_dict
	);