mpm: adding adf400x support to chips

Adding ADF400X driver to MPM. This uses the Boost.Python bound spidev,
and is largely a translation from the C++ driver in UHD.

3 files changed, 216 insertions, 2 deletions

diff --git a/mpm/python/usrp_mpm/chips/CMakeLists.txt b/mpm/python/usrp_mpm/chips/CMakeLists.txt
index ffe1b2419..94b62f33d 100644
--- a/mpm/python/usrp_mpm/chips/CMakeLists.txt
+++ b/mpm/python/usrp_mpm/chips/CMakeLists.txt
@@ -1,5 +1,5 @@
 #
-# Copyright 2017 Ettus Research, National Instruments Company
+# Copyright 2017-2018 Ettus Research, a National Instruments Company
 #
 # SPDX-License-Identifier: GPL-3.0
 #
@@ -8,7 +8,7 @@ SET(USRP_MPM_FILES ${USRP_MPM_FILES})
 SET(USRP_MPM_CHIP_FILES
     ${CMAKE_CURRENT_SOURCE_DIR}/__init__.py
     ${CMAKE_CURRENT_SOURCE_DIR}/lmk04828.py
+    ${CMAKE_CURRENT_SOURCE_DIR}/adf400x.py
 )
 LIST(APPEND USRP_MPM_FILES ${USRP_MPM_CHIP_FILES})
 SET(USRP_MPM_FILES ${USRP_MPM_FILES} PARENT_SCOPE)
-
diff --git a/mpm/python/usrp_mpm/chips/__init__.py b/mpm/python/usrp_mpm/chips/__init__.py
index c8d50d714..15b4a3704 100644
--- a/mpm/python/usrp_mpm/chips/__init__.py
+++ b/mpm/python/usrp_mpm/chips/__init__.py
@@ -7,4 +7,5 @@
 Chips submodule
 """
 
+from .adf400x import ADF400x
 from .lmk04828 import LMK04828
diff --git a/mpm/python/usrp_mpm/chips/adf400x.py b/mpm/python/usrp_mpm/chips/adf400x.py
new file mode 100644
index 000000000..4a33a33a9
--- /dev/null
+++ b/mpm/python/usrp_mpm/chips/adf400x.py
@@ -0,0 +1,213 @@
+#
+# Copyright 2018 Ettus Research, a National Instruments Company
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+"""
+ADF400x driver class
+
+Compatible with ADF4001 and ADF4002.
+"""
+
+from builtins import object
+from usrp_mpm.mpmlog import get_logger
+
+
+BASE_REF_CLOCK_FREQ = 40e6
+DEFAULT_REF_CLOCK_FREQ = 20e6
+
+class ADF400x(object):
+    """
+    Generic driver class for ADF4002 access.
+
+    Inputs:
+    freq : frequency of reference input
+    parent_log : logger of parent
+    """
+    def __init__(self, regs_iface, freq=None, parent_log=None):
+        self.log = \
+            parent_log.getChild("ADF400x") if parent_log is not None \
+            else get_logger("ADF400x")
+        self.regs_iface = regs_iface
+        assert hasattr(self.regs_iface, 'transfer24_8')
+        self.transfer24_8 = regs_iface.transfer24_8
+
+        # Instantiate our own copy of the register mapping and update some values
+        self.adf400x_regs = ADF400xRegs()
+        self.adf400x_regs.ref_counter = 1
+        self.adf400x_regs.charge_pump_current_1 = 7
+        self.adf400x_regs.charge_pump_current_2 = 7
+        self.adf400x_regs.muxout = ADF400xRegs.MUXOUT_DLD
+        self.adf400x_regs.counter_reset = ADF400xRegs.COUNTER_RESET_NORMAL
+        self.adf400x_regs.phase_detector_polarity = ADF400xRegs.PHASE_DETECTOR_POLARITY_POS
+        self.adf400x_regs.charge_pump_mode = ADF400xRegs.CHARGE_PUMP_TRISTATE
+        # Set the N counter
+        if freq is None:
+            freq = DEFAULT_REF_CLOCK_FREQ
+        self._set_n_counter(freq)
+
+        # Now initialize the ADF400x
+        self.program_regs()
+
+    def program_regs(self):
+        """
+        Run through the programming sequence
+        """
+        # No control over CE, only LE, therefore we use the initialization latch method
+        self._write_reg(3)
+        # Conduct a function latch (2)
+        self._write_reg(2)
+        # Write R counter latch (0)
+        self._write_reg(0)
+        # Write N counter latch (1)
+        self._write_reg(1)
+
+    def _write_reg(self, addr):
+        """Write the expected value to the given addr"""
+        reg_val = self.adf400x_regs.get_reg(addr)
+        self.log.trace("Writing {:06x} to spidev".format(reg_val))
+        self.transfer24_8(reg_val)
+
+    def set_lock_to_ext_ref(self, external):
+        """Set the clock source to external"""
+        if bool(external):
+            self.adf400x_regs.charge_pump_mode = ADF400xRegs.CHARGE_PUMP_NORMAL
+        else:
+            self.adf400x_regs.charge_pump_mode = ADF400xRegs.CHARGE_PUMP_TRISTATE
+        self.program_regs()
+
+    def _set_n_counter(self, freq):
+        n_counter = int(BASE_REF_CLOCK_FREQ / freq)
+        if self.adf400x_regs.n_counter == n_counter:
+            self.log.trace("No change to N counter value ({}); returning early".format(n_counter))
+            return
+        self.log.trace("Setting N counter to {}".format(n_counter))
+        # Limits from the datasheet
+        assert 1 <= n_counter <= 8191
+        self.adf400x_regs.n_counter = n_counter
+
+    def set_ref_freq(self, freq):
+        """Set the input reference frequency"""
+        self._set_n_counter(freq)
+        self.program_regs()
+
+
+class ADF400xRegs(object):
+    """Register map for ADF400x"""
+    # TODO: Move each field into an Enum or something
+    # TODO: Add setters/getters for each field
+    # anti backlash widths
+    ANTI_BACKLASH_WIDTH_2_9NS = 0
+    ANTI_BACKLASH_WIDTH_1_3NS = 1
+    ANTI_BACKLASH_WIDTH_6_0NS = 2
+    ANTI_BACKLASH_WIDTH_2_9NS_WAT = 3
+
+    # lock detect precision
+    LOCK_DETECT_PRECISION_3CYC = 0
+    LOCK_DETECT_PRECISION_5CYC = 1
+
+    # charge pump gain
+    CHARGE_PUMP_GAIN_1 = 0
+    CHARGE_PUMP_GAIN_2 = 1
+
+    # counter reset
+    COUNTER_RESET_NORMAL = 0
+    COUNTER_RESET_RESET = 1
+
+    # power down
+    POWER_DOWN_NORMAL = 0
+    POWER_DOWN_ASYNC = 1
+    POWER_DOWN_SYNC = 3
+
+    # muxout
+    MUXOUT_TRISTATE_OUT = 0
+    MUXOUT_DLD = 1
+    MUXOUT_NDIV = 2
+    MUXOUT_AVDD = 3
+    MUXOUT_RDIV = 4
+    MUXOUT_NCH_OD_ALD = 5
+    MUXOUT_SDO = 6
+    MUXOUT_GND = 7
+
+    # phase detector polarity
+    PHASE_DETECTOR_POLARITY_NEG = 0
+    PHASE_DETECTOR_POLARITY_POS = 1
+
+    # charge pump mode
+    CHARGE_PUMP_NORMAL = 0
+    CHARGE_PUMP_TRISTATE = 1
+
+    # fastlock mode
+    FASTLOCK_MODE_DISABLED = 0
+    FASTLOCK_MODE_1 = 1
+    FASTLOCK_MODE_2 = 2
+
+    # timer counter control
+    TIMEOUT_3CYC = 0
+    TIMEOUT_7CYC = 1
+    TIMEOUT_11CYC = 2
+    TIMEOUT_15CYC = 3
+    TIMEOUT_19CYC = 4
+    TIMEOUT_23CYC = 5
+    TIMEOUT_27CYC = 6
+    TIMEOUT_31CYC = 7
+    TIMEOUT_35CYC = 8
+    TIMEOUT_39CYC = 9
+    TIMEOUT_43CYC = 10
+    TIMEOUT_47CYC = 11
+    TIMEOUT_51CYC = 12
+    TIMEOUT_55CYC = 13
+    TIMEOUT_59CYC = 14
+    TIMEOUT_63CYC = 15
+
+    def __init__(self):
+        """Set the default configuration"""
+        self.ref_counter = 0
+        self.n_counter = 0
+        self.charge_pump_current_1 = 0
+        self.charge_pump_current_2 = 0
+        self.anti_backlash_width = ADF400xRegs.ANTI_BACKLASH_WIDTH_2_9NS
+        self.lock_detect_precision = ADF400xRegs.LOCK_DETECT_PRECISION_3CYC
+        self.charge_pump_gain = ADF400xRegs.CHARGE_PUMP_GAIN_1
+        self.counter_reset = ADF400xRegs.COUNTER_RESET_NORMAL
+        self.power_down = ADF400xRegs.POWER_DOWN_NORMAL
+        self.muxout = ADF400xRegs.MUXOUT_TRISTATE_OUT
+        self.phase_detector_polarity = ADF400xRegs.PHASE_DETECTOR_POLARITY_NEG
+        self.charge_pump_mode = ADF400xRegs.CHARGE_PUMP_TRISTATE
+        self.fastlock_mode = ADF400xRegs.FASTLOCK_MODE_DISABLED
+        self.timer_counter_control = ADF400xRegs.TIMEOUT_3CYC
+
+    def get_reg(self, addr):
+        """Get the register value to write to the given addr"""
+        reg = 0
+        if addr == 0:
+            reg |= (self.ref_counter & 0x003FFF) << 2
+            reg |= (self.anti_backlash_width & 0x000003) << 16
+            reg |= (self.lock_detect_precision & 0x000001) << 20
+        elif addr == 1:
+            reg |= (self.n_counter & 0x001FFF) << 8
+            reg |= (self.charge_pump_gain & 0x000001) << 21
+        elif addr == 2:
+            reg |= (self.counter_reset & 0x000001) << 2
+            reg |= (self.power_down & 0x000001) << 3
+            reg |= (self.muxout & 0x000007) << 4
+            reg |= (self.phase_detector_polarity & 0x000001) << 7
+            reg |= (self.charge_pump_mode & 0x000001) << 8
+            reg |= (self.fastlock_mode & 0x000003) << 9
+            reg |= (self.timer_counter_control & 0x00000F) << 11
+            reg |= (self.charge_pump_current_1 & 0x000007) << 15
+            reg |= (self.charge_pump_current_2 & 0x000007) << 18
+            reg |= (self.power_down & 0x000002) << 20
+        elif addr == 3:
+            reg |= (self.counter_reset & 0x000001) << 2
+            reg |= (self.power_down & 0x000001) << 3
+            reg |= (self.muxout & 0x000007) << 4
+            reg |= (self.phase_detector_polarity & 0x000001) << 7
+            reg |= (self.charge_pump_mode & 0x000001) << 8
+            reg |= (self.fastlock_mode & 0x000003) << 9
+            reg |= (self.timer_counter_control & 0x00000F) << 11
+            reg |= (self.charge_pump_current_1 & 0x000007) << 15
+            reg |= (self.charge_pump_current_2 & 0x000007) << 18
+            reg |= (self.power_down & 0x000002) << 20
+        reg |= addr
+        return reg