tmc2240: initial implementation

Signed-off-by: Alex Voinea <voinea.dragos.alexandru@gmail.com>
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

docs/Config_Reference.md

@@ -3307,6 +3307,125 @@ run_current:
 #   HDEC) is interpreted as the MSB of HSTRT in this case).
 ```
 
+### [tmc2240]
+
+Configure a TMC2240 stepper motor driver via SPI bus. To use this
+feature, define a config section with a "tmc2240" prefix followed by
+the name of the corresponding stepper config section (for example,
+"[tmc2240 stepper_x]").
+
+```
+[tmc2240 stepper_x]
+cs_pin:
+#   The pin corresponding to the TMC2240 chip select line. This pin
+#   will be set to low at the start of SPI messages and raised to high
+#   after the message completes. This parameter must be provided.
+#spi_speed:
+#spi_bus:
+#spi_software_sclk_pin:
+#spi_software_mosi_pin:
+#spi_software_miso_pin:
+#   See the "common SPI settings" section for a description of the
+#   above parameters.
+#chain_position:
+#chain_length:
+#   These parameters configure an SPI daisy chain. The two parameters
+#   define the stepper position in the chain and the total chain length.
+#   Position 1 corresponds to the stepper that connects to the MOSI signal.
+#   The default is to not use an SPI daisy chain.
+#interpolate: True
+#   If true, enable step interpolation (the driver will internally
+#   step at a rate of 256 micro-steps). The default is True.
+run_current:
+#   The amount of current (in amps RMS) to configure the driver to use
+#   during stepper movement. This parameter must be provided.
+#hold_current:
+#   The amount of current (in amps RMS) to configure the driver to use
+#   when the stepper is not moving. Setting a hold_current is not
+#   recommended (see TMC_Drivers.md for details). The default is to
+#   not reduce the current.
+#rref: 12000
+#   The resistance (in ohms) of the resistor between IREF and GND. The
+#   default is 12000.
+#stealthchop_threshold: 0
+#   The velocity (in mm/s) to set the "stealthChop" threshold to. When
+#   set, "stealthChop" mode will be enabled if the stepper motor
+#   velocity is below this value. The default is 0, which disables
+#   "stealthChop" mode.
+#driver_MSLUT0: 2863314260
+#driver_MSLUT1: 1251300522
+#driver_MSLUT2: 608774441
+#driver_MSLUT3: 269500962
+#driver_MSLUT4: 4227858431
+#driver_MSLUT5: 3048961917
+#driver_MSLUT6: 1227445590
+#driver_MSLUT7: 4211234
+#driver_W0: 2
+#driver_W1: 1
+#driver_W2: 1
+#driver_W3: 1
+#driver_X1: 128
+#driver_X2: 255
+#driver_X3: 255
+#driver_START_SIN: 0
+#driver_START_SIN90: 247
+#driver_OFFSET_SIN90: 0
+#   These fields control the Microstep Table registers directly. The optimal
+#   wave table is specific to each motor and might vary with current. An
+#   optimal configuration will have minimal print artifacts caused by
+#   non-linear stepper movement. The values specified above are the default
+#   values used by the driver. The value must be specified as a decimal integer
+#   (hex form is not supported). In order to compute the wave table fields,
+#   see the tmc2130 "Calculation Sheet" from the Trinamic website.
+#   Additionally, this driver also has the OFFSET_SIN90 field which can be used
+#   to tune a motor with unbalanced coils. See the `Sine Wave Lookup Table`
+#   section in the datasheet for information about this field and how to tune
+#   it.
+#driver_IHOLDDELAY: 6
+#driver_IRUNDELAY: 4
+#driver_TPOWERDOWN: 10
+#driver_TBL: 2
+#driver_TOFF: 3
+#driver_HEND: 2
+#driver_HSTRT: 5
+#driver_FD3: 0
+#driver_TPFD: 4
+#driver_CHM: 0
+#driver_VHIGHFS: 0
+#driver_VHIGHCHM: 0
+#driver_DISS2G: 0
+#driver_DISS2VS: 0
+#driver_PWM_AUTOSCALE: True
+#driver_PWM_AUTOGRAD: True
+#driver_PWM_FREQ: 0
+#driver_FREEWHEEL: 0
+#driver_PWM_GRAD: 0
+#driver_PWM_OFS: 29
+#driver_PWM_REG: 4
+#driver_PWM_LIM: 12
+#driver_SGT: 0
+#driver_SEMIN: 0
+#driver_SEUP: 0
+#driver_SEMAX: 0
+#driver_SEDN: 0
+#driver_SEIMIN: 0
+#driver_SFILT: 0
+#   Set the given register during the configuration of the TMC2240
+#   chip. This may be used to set custom motor parameters. The
+#   defaults for each parameter are next to the parameter name in the
+#   above list.
+#diag0_pin:
+#diag1_pin:
+#   The micro-controller pin attached to one of the DIAG lines of the
+#   TMC2240 chip. Only a single diag pin should be specified. The pin
+#   is "active low" and is thus normally prefaced with "^!". Setting
+#   this creates a "tmc2240_stepper_x:virtual_endstop" virtual pin
+#   which may be used as the stepper's endstop_pin. Doing this enables
+#   "sensorless homing". (Be sure to also set driver_SGT to an
+#   appropriate sensitivity value.) The default is to not enable
+#   sensorless homing.
+```
+
 ### [tmc5160]
 
 Configure a TMC5160 stepper motor driver via SPI bus. To use this