X-Git-Url: https://git.ayoreis.com/Adafruit_Blinka-hackapet.git/blobdiff_plain/ecba441c03a58ce97b3c1c769cb9c76675abbf7f..3306ddab1a11a2d5ccd77d93eeb97a91c114e281:/src/adafruit_blinka/microcontroller/ft232h/spi.py?ds=inline

diff --git a/src/adafruit_blinka/microcontroller/ft232h/spi.py b/src/adafruit_blinka/microcontroller/ft232h/spi.py
index 26e1bbb..a260e72 100644
--- a/src/adafruit_blinka/microcontroller/ft232h/spi.py
+++ b/src/adafruit_blinka/microcontroller/ft232h/spi.py
@@ -3,48 +3,52 @@ from adafruit_blinka.microcontroller.ft232h.pin import Pin
 class SPI:
     MSB = 0
 
-    baudrate = 100000
-    mode = 0
-    bits = 8
-
     def __init__(self):
         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):
-        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)
-        port = self._spi.get_port(self.cs, self.freq, self.mode)
-        port.write(buf[start:end])
+        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
+            self._port.write(buf[chunk_start:chunk_end])
+        if 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)
-        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)
-        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
\ No newline at end of file
+            buffer_in[in_start+i] = b