tmc2130: Share config reading helpers with tmc2208.py code

Add helper function for reading current, microsteps, and stealthchop
settings from the config file.  Use these helpers in both the tmc2130
and tmc2208 modules.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

2 files changed, 57 insertions, 76 deletions

diff --git a/klippy/extras/tmc2130.py b/klippy/extras/tmc2130.py
index ac99edc4..acb1ca51 100644
--- a/klippy/extras/tmc2130.py
+++ b/klippy/extras/tmc2130.py
@@ -94,6 +94,50 @@ class FieldHelper:
 
 
 ######################################################################
+# Config reading helpers
+######################################################################
+
+def current_bits(current, sense_resistor, vsense_on):
+    sense_resistor += 0.020
+    vsense = 0.32
+    if vsense_on:
+        vsense = 0.18
+    cs = int(32. * current * sense_resistor * math.sqrt(2.) / vsense - 1. + .5)
+    return max(0, min(31, cs))
+
+def get_config_current(config):
+    vsense = False
+    run_current = config.getfloat('run_current', above=0., maxval=2.)
+    hold_current = config.getfloat('hold_current', run_current,
+                                   above=0., maxval=2.)
+    sense_resistor = config.getfloat('sense_resistor', 0.110, above=0.)
+    irun = current_bits(run_current, sense_resistor, vsense)
+    ihold = current_bits(hold_current, sense_resistor, vsense)
+    if irun < 16 and ihold < 16:
+        vsense = True
+        irun = current_bits(run_current, sense_resistor, vsense)
+        ihold = current_bits(hold_current, sense_resistor, vsense)
+    return vsense, irun, ihold
+
+def get_config_microsteps(config):
+    steps = {'256': 0, '128': 1, '64': 2, '32': 3, '16': 4,
+             '8': 5, '4': 6, '2': 7, '1': 8}
+    return config.getchoice('microsteps', steps)
+
+def get_config_stealthchop(config, tmc_freq):
+    mres = get_config_microsteps(config)
+    velocity = config.getfloat('stealthchop_threshold', 0., minval=0.)
+    if not velocity:
+        return mres, False, 0
+    stepper_name = config.get_name().split()[1]
+    stepper_config = config.getsection(stepper_name)
+    step_dist = stepper_config.getfloat('step_distance')
+    step_dist_256 = step_dist / (1 << mres)
+    threshold = int(tmc_freq * step_dist_256 / velocity + .5)
+    return mres, True, max(0, min(0xfffff, threshold))
+
+
+######################################################################
 # TMC2130 printer object
 ######################################################################
 
@@ -112,17 +156,10 @@ class TMC2130:
             "DUMP_TMC", "STEPPER", self.name,
             self.cmd_DUMP_TMC, desc=self.cmd_DUMP_TMC_help)
         # Get config for initial driver settings
-        self.field_helper = FieldHelper(Fields)
-        run_current = config.getfloat('run_current', above=0., maxval=2.)
-        hold_current = config.getfloat('hold_current', run_current,
-                                       above=0., maxval=2.)
-        sense_resistor = config.getfloat('sense_resistor', 0.110, above=0.)
-        steps = {'256': 0, '128': 1, '64': 2, '32': 3, '16': 4,
-                 '8': 5, '4': 6, '2': 7, '1': 8}
-        self.mres = config.getchoice('microsteps', steps)
+        self.fields = FieldHelper(Fields)
         interpolate = config.getboolean('interpolate', True)
-        sc_velocity = config.getfloat('stealthchop_threshold', 0., minval=0.)
-        sc_threshold = self.velocity_to_clock(config, sc_velocity)
+        self.mres, en_pwm, sc_threshold = get_config_stealthchop(
+            config, TMC_FREQUENCY)
         iholddelay = config.getint('driver_IHOLDDELAY', 8, minval=0, maxval=15)
         tpowerdown = config.getint('driver_TPOWERDOWN', 0, minval=0, maxval=255)
         blank_time_select = config.getint('driver_BLANK_TIME_SELECT', 1,
@@ -135,16 +172,9 @@ class TMC2130:
         pwm_freq = config.getint('driver_PWM_FREQ', 1, minval=0, maxval=3)
         pwm_grad = config.getint('driver_PWM_GRAD', 4, minval=0, maxval=255)
         pwm_ampl = config.getint('driver_PWM_AMPL', 128, minval=0, maxval=255)
-        # calculate current
-        vsense = False
-        irun = self.current_bits(run_current, sense_resistor, vsense)
-        ihold = self.current_bits(hold_current, sense_resistor, vsense)
-        if irun < 16 and ihold < 16:
-            vsense = True
-            irun = self.current_bits(run_current, sense_resistor, vsense)
-            ihold = self.current_bits(hold_current, sense_resistor, vsense)
+        vsense, irun, ihold = get_config_current(config)
         # Configure registers
-        self.reg_GCONF = (sc_velocity > 0.) << 2
+        self.reg_GCONF = en_pwm << 2
         self.set_register("GCONF", self.reg_GCONF)
         self.set_register("CHOPCONF", (
             toff | (hstrt << 4) | (hend << 7) | (blank_time_select << 15)
@@ -152,26 +182,10 @@ class TMC2130:
         self.set_register("IHOLD_IRUN",
                           ihold | (irun << 8) | (iholddelay << 16))
         self.set_register("TPOWERDOWN", tpowerdown)
-        self.set_register("TPWMTHRS", max(0, min(0xfffff, sc_threshold)))
+        self.set_register("TPWMTHRS", sc_threshold)
         self.set_register("COOLCONF", sgt << 16)
         self.set_register("PWMCONF", (
             pwm_ampl | (pwm_grad << 8) | (pwm_freq << 16) | (pwm_scale << 18)))
-    def current_bits(self, current, sense_resistor, vsense_on):
-        sense_resistor += 0.020
-        vsense = 0.32
-        if vsense_on:
-            vsense = 0.18
-        cs = int(32. * current * sense_resistor * math.sqrt(2.) / vsense
-                 - 1. + .5)
-        return max(0, min(31, cs))
-    def velocity_to_clock(self, config, velocity):
-        if not velocity:
-            return 0
-        stepper_name = config.get_name().split()[1]
-        stepper_config = config.getsection(stepper_name)
-        step_dist = stepper_config.getfloat('step_distance')
-        step_dist_256 = step_dist / (1 << self.mres)
-        return int(TMC_FREQUENCY * step_dist_256 / velocity + .5)
     def setup_pin(self, pin_type, pin_params):
         if pin_type != 'endstop' or pin_params['pin'] != 'virtual_endstop':
             raise pins.error("tmc2130 virtual endstop only useful as endstop")
@@ -200,7 +214,7 @@ class TMC2130:
         logging.info("DUMP_TMC %s", self.name)
         for reg_name in ReadRegisters:
             val = self.get_register(reg_name)
-            msg = self.field_helper.pretty_format(reg_name, val)
+            msg = self.fields.pretty_format(reg_name, val)
             logging.info(msg)
             gcode.respond_info(msg)
 
diff --git a/klippy/extras/tmc2208.py b/klippy/extras/tmc2208.py
index aa11a21c..60bf5a20 100644
--- a/klippy/extras/tmc2208.py
+++ b/klippy/extras/tmc2208.py
@@ -3,7 +3,7 @@
 # Copyright (C) 2018  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
-import math, logging, collections
+import logging, collections
 import tmc2130
 
 TMC_FREQUENCY=12000000.
@@ -292,30 +292,14 @@ class TMC2208:
         self.fields.set_field("pdn_disable", True)
         self.fields.set_field("mstep_reg_select", True)
         self.fields.set_field("multistep_filt", True)
-        steps = {'256': 0, '128': 1, '64': 2, '32': 3, '16': 4,
-                 '8': 5, '4': 6, '2': 7, '1': 8}
-        mres = config.getchoice('microsteps', steps)
-        self.fields.set_field("MRES", mres)
-        # Calculate current
-        vsense = False
-        run_current = config.getfloat('run_current', above=0., maxval=2.)
-        hold_current = config.getfloat('hold_current', run_current,
-                                       above=0., maxval=2.)
-        sense_resistor = config.getfloat('sense_resistor', 0.110, above=0.)
-        irun = self.current_bits(run_current, sense_resistor, vsense)
-        ihold = self.current_bits(hold_current, sense_resistor, vsense)
-        if irun < 16 and ihold < 16:
-            vsense = True
-            irun = self.current_bits(run_current, sense_resistor, vsense)
-            ihold = self.current_bits(hold_current, sense_resistor, vsense)
+        vsense, irun, ihold = tmc2130.get_config_current(config)
         self.fields.set_field("vsense", vsense)
         self.fields.set_field("IHOLD", ihold)
         self.fields.set_field("IRUN", irun)
-        # Setup stealthchop
-        sc_velocity = config.getfloat('stealthchop_threshold', 0., minval=0.)
-        sc_threshold = self.velocity_to_clock(config, sc_velocity, mres)
-        self.fields.set_field("en_spreadCycle", not sc_velocity)
-        self.fields.set_field("TPWMTHRS", sc_threshold)
+        mres, en, thresh = tmc2130.get_config_stealthchop(config, TMC_FREQUENCY)
+        self.fields.set_field("MRES", mres)
+        self.fields.set_field("en_spreadCycle", not en)
+        self.fields.set_field("TPWMTHRS", thresh)
         # Allow other registers to be set from the config
         set_config_field = self.fields.set_config_field
         set_config_field(config, "toff", 3)
@@ -332,23 +316,6 @@ class TMC2208:
         set_config_field(config, "pwm_autograd", True)
         set_config_field(config, "PWM_REG", 8)
         set_config_field(config, "PWM_LIM", 12)
-    def current_bits(self, current, sense_resistor, vsense_on):
-        sense_resistor += 0.020
-        vsense = 0.32
-        if vsense_on:
-            vsense = 0.18
-        cs = int(32. * current * sense_resistor * math.sqrt(2.) / vsense
-                 - 1. + .5)
-        return max(0, min(31, cs))
-    def velocity_to_clock(self, config, velocity, mres):
-        if not velocity:
-            return 0
-        stepper_name = config.get_name().split()[1]
-        stepper_config = config.getsection(stepper_name)
-        step_dist = stepper_config.getfloat('step_distance')
-        step_dist_256 = step_dist / (1 << mres)
-        threshold = int(TMC_FREQUENCY * step_dist_256 / velocity + .5)
-        return max(0, min(0xfffff, threshold))
     def build_config(self):
         bit_ticks = int(self.mcu.get_adjusted_freq() / 9000.)
         self.mcu.add_config_cmd(