1 files changed, 57 insertions, 0 deletions
diff --git a/circuitpython/supervisor/shared/external_flash/qspi_flash.c b/circuitpython/supervisor/shared/external_flash/qspi_flash.c
new file mode 100644
index 0000000..293654b
--- /dev/null
+++ b/circuitpython/supervisor/shared/external_flash/qspi_flash.c
@@ -0,0 +1,57 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016, 2017, 2018 Scott Shawcroft for Adafruit Industries
+ *
+ * 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 "supervisor/spi_flash_api.h"
+
+#include "supervisor/shared/external_flash/common_commands.h"
+#include "supervisor/shared/external_flash/qspi_flash.h"
+
+void check_quad_enable(const external_flash_device *device) {
+    if (device->quad_enable_bit_mask == 0x00) {
+        return;
+    }
+
+    // Verify that QSPI mode is enabled.
+    uint8_t status;
+    if (device->single_status_byte) {
+        spi_flash_read_command(CMD_READ_STATUS, &status, 1);
+    } else {
+        spi_flash_read_command(CMD_READ_STATUS2, &status, 1);
+    }
+
+    // Check the quad enable bit.
+    if ((status & device->quad_enable_bit_mask) == 0) {
+        uint8_t full_status[2] = {0x00, device->quad_enable_bit_mask};
+        spi_flash_command(CMD_ENABLE_WRITE);
+        if (device->write_status_register_split) {
+            spi_flash_write_command(CMD_WRITE_STATUS_BYTE2, full_status + 1, 1);
+        } else if (device->single_status_byte) {
+            spi_flash_write_command(CMD_WRITE_STATUS_BYTE1, full_status + 1, 1);
+        } else {
+            spi_flash_write_command(CMD_WRITE_STATUS_BYTE1, full_status, 2);
+        }
+    }
+}