Adds softpwm files

source/py_softpwm.c

@@ -0,0 +1,214 @@
+/*
+Copyright (c) 2016 Robert Wolterman
+
+Original BBIO Author Justin Cooper
+Modified for CHIP_IO Author Robert Wolterman
+
+This file incorporates work covered by the following copyright and
+permission notice, all modified code adopts the original license:
+
+Copyright (c) 2013 Adafruit
+Author: Justin Cooper
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+#include "Python.h"
+#include "constants.h"
+#include "common.h"
+#include "c_softpwm.h"
+
+// python function cleanup()
+static PyObject *py_cleanup(PyObject *self, PyObject *args)
+{
+    // unexport the PWM
+    softpwm_cleanup();
+
+    Py_RETURN_NONE;
+}
+
+// python function start(channel, duty_cycle, freq)
+static PyObject *py_start_channel(PyObject *self, PyObject *args, PyObject *kwargs)
+{
+    char key[8];
+    char *channel;
+    float frequency = 2000.0;
+    float duty_cycle = 0.0;
+    int polarity = 0;
+    static char *kwlist[] = {"channel", "duty_cycle", "frequency", "polarity", NULL};
+
+    if (!PyArg_ParseTupleAndKeywords(args, kwargs, "s|ffi", kwlist, &channel, &duty_cycle, &frequency, &polarity)) {
+        return NULL;
+    }
+
+    if (!get_key(channel, key)) {
+        PyErr_SetString(PyExc_ValueError, "Invalid PWM key or name.");
+        return NULL;
+    }
+
+    if (duty_cycle < 0.0 || duty_cycle > 100.0)
+    {
+        PyErr_SetString(PyExc_ValueError, "duty_cycle must have a value from 0.0 to 100.0");
+        return NULL;
+    }
+
+    if (frequency <= 0.0)
+    {
+        PyErr_SetString(PyExc_ValueError, "frequency must be greater than 0.0");
+        return NULL;
+    }
+
+    if (polarity < 0 || polarity > 1) {
+        PyErr_SetString(PyExc_ValueError, "polarity must be either 0 or 1");
+        return NULL;
+    }
+
+    if (!softpwm_start(key, duty_cycle, frequency, polarity))
+        return NULL;
+
+    Py_RETURN_NONE;
+}
+
+// python function stop(channel)
+static PyObject *py_stop_channel(PyObject *self, PyObject *args, PyObject *kwargs)
+{
+    char key[8];
+    char *channel;
+
+    if (!PyArg_ParseTuple(args, "s", &channel))
+        return NULL;
+
+    if (!get_key(channel, key)) {
+        PyErr_SetString(PyExc_ValueError, "Invalid PWM key or name.");
+        return NULL;
+    }
+
+    softpwm_disable(key);
+
+    Py_RETURN_NONE;
+}
+
+// python method PWM.set_duty_cycle(channel, duty_cycle)
+static PyObject *py_set_duty_cycle(PyObject *self, PyObject *args, PyObject *kwargs)
+{
+    char key[8];
+    char *channel;
+    float duty_cycle = 0.0;
+    static char *kwlist[] = {"channel", "duty_cycle", NULL};
+
+    if (!PyArg_ParseTupleAndKeywords(args, kwargs, "s|f", kwlist, &channel, &duty_cycle))
+        return NULL;
+
+    if (duty_cycle < 0.0 || duty_cycle > 100.0)
+    {
+        PyErr_SetString(PyExc_ValueError, "duty_cycle must have a value from 0.0 to 100.0");
+        return NULL;
+    }
+
+    if (!get_key(channel, key)) {
+        PyErr_SetString(PyExc_ValueError, "Invalid PWM key or name.");
+        return NULL;
+    }
+
+    if (softpwm_set_duty_cycle(key, duty_cycle) == -1) {
+        PyErr_SetString(PyExc_RuntimeError, "You must start() the PWM channel first");
+        return NULL;
+    }
+
+    Py_RETURN_NONE;
+}
+
+// python method PWM.set_frequency(channel, frequency)
+static PyObject *py_set_frequency(PyObject *self, PyObject *args, PyObject *kwargs)
+{
+    char key[8];
+    char *channel;
+    float frequency = 1.0;
+    static char *kwlist[] = {"channel", "frequency", NULL};
+
+    if (!PyArg_ParseTupleAndKeywords(args, kwargs, "s|f", kwlist, &channel, &frequency))
+        return NULL;
+
+    if ((frequency <= 0.0) || (frequency > 10000.0))
+    {
+        PyErr_SetString(PyExc_ValueError, "frequency must be greater than 0.0 and less than 10000.0");
+        return NULL;
+    }
+
+    if (!get_key(channel, key)) {
+        PyErr_SetString(PyExc_ValueError, "Invalid PWM key or name.");
+        return NULL;
+    }
+
+    if (pwm_set_frequency(key, frequency) == -1) {
+        PyErr_SetString(PyExc_RuntimeError, "You must start() the PWM channel first");
+        return NULL;
+    }
+
+    Py_RETURN_NONE;
+}
+
+
+static const char moduledocstring[] = "Software PWM functionality of a CHIP using Python";
+
+PyMethodDef pwm_methods[] = {
+    {"start", (PyCFunction)py_start_channel, METH_VARARGS | METH_KEYWORDS, "Set up and start the PWM channel.  channel can be in the form of 'XIO-P0', or 'U14_13'"},
+    {"stop", (PyCFunction)py_stop_channel, METH_VARARGS | METH_KEYWORDS, "Stop the PWM channel.  channel can be in the form of 'XIO-P0', or 'U14_13'"},
+    { "set_duty_cycle", (PyCFunction)py_set_duty_cycle, METH_VARARGS, "Change the duty cycle\ndutycycle - between 0.0 and 100.0" },
+    { "set_frequency", (PyCFunction)py_set_frequency, METH_VARARGS, "Change the frequency\nfrequency - frequency in Hz (freq > 0.0)" },
+    {"cleanup", py_cleanup, METH_VARARGS, "Clean up by resetting all GPIO channels that have been used by this program to INPUT with no pullup/pulldown and no event detection"},
+    //{"setwarnings", py_setwarnings, METH_VARARGS, "Enable or disable warning messages"},
+    {NULL, NULL, 0, NULL}
+};
+
+#if PY_MAJOR_VERSION > 2
+static struct PyModuleDef chippwmmodule = {
+    PyModuleDef_HEAD_INIT,
+    "SOFTPWM",       // name of module
+    moduledocstring,  // module documentation, may be NULL
+    -1,               // size of per-interpreter state of the module, or -1 if the module keeps state in global variables.
+    pwm_methods
+};
+#endif
+
+#if PY_MAJOR_VERSION > 2
+PyMODINIT_FUNC PyInit_SOFTPWM(void)
+#else
+PyMODINIT_FUNC initSOFTPWM(void)
+#endif
+{
+    PyObject *module = NULL;
+
+#if PY_MAJOR_VERSION > 2
+    if ((module = PyModule_Create(&chippwmmodule)) == NULL)
+       return NULL;
+#else
+    if ((module = Py_InitModule3("SOFTPWM", pwm_methods, moduledocstring)) == NULL)
+       return;
+#endif
+
+   define_constants(module);
+
+
+#if PY_MAJOR_VERSION > 2
+    return module;
+#else
+    return;
+#endif
+}