complete coding to initialize and write.

Author: yuuu

src/mruby_esp32_spi.c

@@ -8,14 +8,22 @@
 #include <stdio.h>
 #include <string.h>
 
-#ifdef ESP_PLATFORM
+#if ESP_PLATFORM
 #include "freertos/FreeRTOS.h"
 #include "freertos/task.h"
+#include "driver/spi_master.h"
 #include "esp_log.h"
 #else
 #define ESP_LOGI(tag, fmt, ...)  printf(fmt, __VA_ARGS__)
 #endif
 
+#ifdef CONFIG_IDF_TARGET_ESP32
+#define PIN_NUM_MISO 19
+#define PIN_NUM_MOSI 23
+#define PIN_NUM_CLK  18
+#define PIN_NUM_CS   5
+#endif
+
 #define TAG ("mruby-esp32-spi")
 
 typedef struct spi_t {
@@ -24,6 +32,9 @@ typedef struct spi_t {
   mrb_int mode;
   mrb_int first_bit;
   mrb_state *mrb;
+#ifdef ESP_PLATFORM
+  spi_device_handle_t *device_handle;
+#endif
 } spi_t;
 
 static void mrb_spi_free(mrb_state *mrb, void *p);
@@ -32,6 +43,12 @@ static const struct mrb_data_type mrb_spi = {
   "mrb_mruby_esp32_spi", mrb_spi_free
 };
 
+#if ESP_PLATFORM
+static void
+mrb_spi_pre_transfer_callback(spi_transaction_t *t) {
+}
+#endif
+
 static void
 mrb_spi_free(mrb_state *mrb, void *p) {
   spi_t *spi = (spi_t *)p;
@@ -51,6 +68,34 @@ mrb_spi_init(mrb_state *mrb, mrb_value self) {
     spi->unit, spi->mode, spi->first_bit, spi->frequency
   );
 
+#ifdef ESP_PLATFORM
+  esp_err_t ret;
+  spi_device_handle_t device_handle;
+  spi_bus_config_t bus_config = {
+    .miso_io_num = PIN_NUM_MISO,
+    .mosi_io_num = PIN_NUM_MOSI,
+    .sclk_io_num = PIN_NUM_CLK,
+    .quadwp_io_num = -1,
+    .quadhd_io_num = -1,
+    .max_transfer_sz = 0
+  };
+  spi_device_interface_config_t device_config = {
+    .clock_speed_hz = spi->frequency,
+    .mode = spi->mode,
+    .spics_io_num = PIN_NUM_CS,
+    .queue_size = 7,
+    .pre_cb = mrb_spi_pre_transfer_callback,
+  };
+
+  ret = spi_bus_initialize(VSPI_HOST, &bus_config, SPI_DMA_CH_AUTO);
+  ESP_ERROR_CHECK(ret);
+
+  ret = spi_bus_add_device(VSPI_HOST, &device_config, &device_handle);
+  ESP_ERROR_CHECK(ret);
+
+  spi->device_handle = device_handle;
+#endif
+
   mrb_data_init(self, spi, &mrb_spi);
 
   return self;
@@ -68,6 +113,9 @@ mrb_spi_setmode(mrb_state *mrb, mrb_value self) {
     spi->unit, spi->mode, spi->first_bit, spi->frequency
   );
 
+#ifdef ESP_PLATFORM
+#endif
+
   return self;
 }
 
@@ -79,15 +127,31 @@ mrb_spi_read(mrb_state *mrb, mrb_value self) {
   mrb_get_args(mrb, "i", &read_bytes);
   ESP_LOGI(TAG, "read(%d)", read_bytes);
 
+#ifdef ESP_PLATFORM
+#endif
+
   return self;
 }
 
 static mrb_value
 mrb_spi_write(mrb_state *mrb, mrb_value self) {
   spi_t *spi = (spi_t *) DATA_PTR(self);
-  mrb_value data;
+  char *data;
+  mrb_int len;
+
+  mrb_get_args(mrb, "s", &data, &len);
+  ESP_LOGI(TAG, "write(%s)", data);
 
-  mrb_get_args(mrb, "S", &data);
+#ifdef ESP_PLATFORM
+  esp_err_t ret;
+  spi_transaction_t transaction = {
+    .length = len * 8,
+    .tx_buffer = data,
+    .user = (void*)0,
+  };
+  ret = spi_device_polling_transmit(spi->device_handle, &transaction);
+  assert(ret == ESP_OK);
+#endif
 
   return self;
 }