drivers/memory/spiflash: Change from hard-coded soft SPI to generic SPI.

The SPI flash driver now supports using an arbitrary SPI object to
communicate with the flash chip, and in particular can use a hardware SPI
peripheral.

Author: dpgeorge

drivers/memory/spiflash.c

@@ -49,10 +49,8 @@ STATIC uint8_t buf[SECTOR_SIZE];
 void mp_spiflash_init(mp_spiflash_t *self) {
     mp_hal_pin_write(self->cs, 1);
     mp_hal_pin_output(self->cs);
-    mp_hal_pin_write(self->spi.sck, 0);
-    mp_hal_pin_output(self->spi.sck);
-    mp_hal_pin_output(self->spi.mosi);
-    mp_hal_pin_input(self->spi.miso);
+    const mp_machine_spi_p_t *protocol = self->spi->type->protocol;
+    protocol->init(self->spi, 0, NULL, (mp_map_t*)&mp_const_empty_map);
 }
 
 STATIC void mp_spiflash_acquire_bus(mp_spiflash_t *self) {
@@ -66,7 +64,8 @@ STATIC void mp_spiflash_release_bus(mp_spiflash_t *self) {
 }
 
 STATIC void mp_spiflash_transfer(mp_spiflash_t *self, size_t len, const uint8_t *src, uint8_t *dest) {
-    mp_machine_soft_spi_transfer(&self->spi.base, len, src, dest);
+    const mp_machine_spi_p_t *protocol = self->spi->type->protocol;
+    protocol->transfer(self->spi, len, src, dest);
 }
 
 STATIC int mp_spiflash_wait_sr(mp_spiflash_t *self, uint8_t mask, uint8_t val, uint32_t timeout) {

drivers/memory/spiflash.h

@@ -30,8 +30,7 @@
 
 typedef struct _mp_spiflash_t {
     mp_hal_pin_obj_t cs;
-    // TODO replace with generic SPI object
-    mp_machine_soft_spi_obj_t spi;
+    mp_obj_base_t *spi; // object must have protocol pointing to mp_machine_spi_p_t struct
 } mp_spiflash_t;
 
 void mp_spiflash_init(mp_spiflash_t *self);

stmhal/storage.c

@@ -176,17 +176,19 @@ static uint8_t *flash_cache_get_addr_for_read(uint32_t flash_addr) {
 
 static bool flash_is_initialised = false;
 
+STATIC const mp_machine_soft_spi_obj_t spiflash_spi_bus = {
+    .base = {&mp_machine_soft_spi_type},
+    .delay_half = MICROPY_PY_MACHINE_SPI_MIN_DELAY,
+    .polarity = 0,
+    .phase = 0,
+    .sck = &MICROPY_HW_SPIFLASH_SCK,
+    .mosi = &MICROPY_HW_SPIFLASH_MOSI,
+    .miso = &MICROPY_HW_SPIFLASH_MISO,
+};
+
 STATIC const mp_spiflash_t spiflash = {
     .cs = &MICROPY_HW_SPIFLASH_CS,
-    .spi = {
-        .base = {&mp_machine_soft_spi_type},
-        .delay_half = MICROPY_PY_MACHINE_SPI_MIN_DELAY,
-        .polarity = 0,
-        .phase = 0,
-        .sck = &MICROPY_HW_SPIFLASH_SCK,
-        .mosi = &MICROPY_HW_SPIFLASH_MOSI,
-        .miso = &MICROPY_HW_SPIFLASH_MISO,
-    },
+    .spi = (mp_obj_base_t*)&spiflash_spi_bus.base,
 };
 
 #endif