coredevice: add AD9154 SPI access driver

artiq/coredevice/ad9154_spi.py

@@ -0,0 +1,24 @@
+from artiq.language.core import kernel
+
+
+class AD9154:
+    """Kernel interface to AD9154 registers, using non-realtime SPI."""
+
+    def __init__(self, dmgr, spi_device, chip_select):
+        self.core = dmgr.get("core")
+        self.bus = dmgr.get(spi_device)
+        self.chip_select = chip_select
+
+    @kernel
+    def setup_bus(self, write_div=16, read_div=16):
+        self.bus.set_config_mu(0, write_div, read_div)
+        self.bus.set_xfer(self.chip_select, 24, 0)
+
+    @kernel
+    def write(self, addr, data):
+        self.bus.write((addr << 16) | (data<< 8))
+
+    @kernel
+    def read(self, addr):
+        self.write((1 << 15) | addr, 0)
+        return self.bus.read()