Fix some SPI-related code to get BME280 example code working

[hackapet/Adafruit_Blinka.git] / src / adafruit_blinka / microcontroller / ft232h / spi.py

diff --git a/src/adafruit_blinka/microcontroller/ft232h/spi.py b/src/adafruit_blinka/microcontroller/ft232h/spi.py
index 6a2d18f9334f0b9156d0d85410a3bfbd6a9af8eb..a260e7206e42ed2f4e89f8468e481d01f37f7301 100644 (file)
--- a/src/adafruit_blinka/microcontroller/ft232h/spi.py
+++ b/src/adafruit_blinka/microcontroller/ft232h/spi.py
@@ -3,55 +3,52 @@ from adafruit_blinka.microcontroller.ft232h.pin import Pin
 class SPI:
     MSB = 0
 
 class SPI:
     MSB = 0
 

-    baudrate = 100000
-    mode = 0
-    bits = 8
-

     def __init__(self):
     def __init__(self):

-        # change GPIO controller to SPI

         from pyftdi.spi import SpiController
         self._spi = SpiController(cs_count=1)
         self._spi.configure('ftdi:///1')
         from pyftdi.spi import SpiController
         self._spi = SpiController(cs_count=1)
         self._spi.configure('ftdi:///1')

+        self._port = self._spi.get_port(0)
+        self._port.set_frequency(100000)
+        self._port._cpol = 0
+        self._port._cpha = 0
+        # Change GPIO controller to SPI

         Pin.ft232h_gpio = self._spi.get_gpio()
 
     def init(self, baudrate=100000, polarity=0, phase=0, bits=8,
                   firstbit=MSB, sck=None, mosi=None, miso=None):
         Pin.ft232h_gpio = self._spi.get_gpio()
 
     def init(self, baudrate=100000, polarity=0, phase=0, bits=8,
                   firstbit=MSB, sck=None, mosi=None, miso=None):

-        self.cs = 0
-        self.freq = baudrate
-        if polarity == 0 and phase == 0:
-            self.mode = 0
-        elif polarity == 0 and phase == 1:
-            self.mode = 1
-        elif polarity == 1 and phase == 0:
-            raise ValueError("SPI mode 2 is not supported.")
-        elif polarity == 1 and phase == 1:
-            self.mode = 3
-        else:
-            raise ValueError("Unknown SPI mode.")
+        self._port.set_frequency(baudrate)
+        # FTDI device can only support mode 0 and mode 2
+        # due to the limitation of MPSSE engine.
+        # This means CPHA must = 0
+        self._port._cpol = polarity
+        if phase != 0:
+            raise ValueError("Only SPI phase 0 is supported by FT232H.")
+        self._port._cpha = phase
+
+    @property
+    def frequency(self):
+        return self._port.frequency

 
     def write(self, buf, start=0, end=None):
         end = end if end else len(buf)
 
     def write(self, buf, start=0, end=None):
         end = end if end else len(buf)

-        port = self._spi.get_port(self.cs, self.freq, self.mode)

         chunks, rest = divmod(end - start, self._spi.PAYLOAD_MAX_LENGTH)
         for i in range(chunks):
             chunk_start = start + i * self._spi.PAYLOAD_MAX_LENGTH
             chunk_end = chunk_start + self._spi.PAYLOAD_MAX_LENGTH
         chunks, rest = divmod(end - start, self._spi.PAYLOAD_MAX_LENGTH)
         for i in range(chunks):
             chunk_start = start + i * self._spi.PAYLOAD_MAX_LENGTH
             chunk_end = chunk_start + self._spi.PAYLOAD_MAX_LENGTH

-            port.write(buf[chunk_start:chunk_end])
+            self._port.write(buf[chunk_start:chunk_end])

         if rest:
         if rest:

-            port.write(buf[-1*rest:])
+            self._port.write(buf[-1*rest:])

 
     def readinto(self, buf, start=0, end=None, write_value=0):
         end = end if end else len(buf)
 
     def readinto(self, buf, start=0, end=None, write_value=0):
         end = end if end else len(buf)

-        port = self._spi.get_port(self.cs, self.freq, self.mode)
-        result = port.read(end-start)
+        result = self._port.read(end-start)

         for i, b in enumerate(result):
             buf[start+i] = b
 
     def write_readinto(self, buffer_out, buffer_in,  out_start=0, out_end=None, in_start=0, in_end=None):
         out_end = out_end if out_end else len(buffer_out)
         in_end = in_end if in_end else len(buffer_in)
         for i, b in enumerate(result):
             buf[start+i] = b
 
     def write_readinto(self, buffer_out, buffer_in,  out_start=0, out_end=None, in_start=0, in_end=None):
         out_end = out_end if out_end else len(buffer_out)
         in_end = in_end if in_end else len(buffer_in)

-        port = self._spi.get_port(self.cs, self.freq, self.mode)
-        result = port.exchange(buffer_out[out_start:out_end],
-                               in_end-in_start)
+        result = self._port.exchange(buffer_out[out_start:out_end],
+                                     in_end-in_start, duplex=True)

         for i, b in enumerate(result):
             buffer_in[in_start+i] = b
         for i, b in enumerate(result):
             buffer_in[in_start+i] = b