pwm.hpp: Add C++ wrapper around Pwm

* maa_pwm_context becomes an opaque pointer
* C++ wrapper class Pwm
* swig now uses C++ wrapper Pwm to generate API

Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>

api/pwm.h

@@ -39,16 +39,7 @@ extern "C" {
 
 #include "maa.h"
 
-/**
- * A strucutre representing a PWM pin
- */
-typedef struct {
-    /*@{*/
-    int pin; /**< the pin number, as known to the os. */
-    int chipid; /**< the chip id, which the pwm resides */
-    FILE *duty_fp; /**< File pointer to duty file */
-    /*@}*/
-} maa_pwm_context;
+typedef struct _pwm* maa_pwm_context;
 
 /** Initialise pwm_context, uses board mapping.
  *
@@ -56,7 +47,7 @@ typedef struct {
  *
  * @return maa_pwm_context The returned initialised pwm context
  */
-maa_pwm_context* maa_pwm_init(int pin);
+maa_pwm_context maa_pwm_init(int pin);
 
 /** Initialise pwm_context, raw mode.
  *
@@ -65,7 +56,7 @@ maa_pwm_context* maa_pwm_init(int pin);
  *
  * @return maa_pwm_context The returned initialised pwm context
  */
-maa_pwm_context* maa_pwm_init_raw(int chipid, int pin);
+maa_pwm_context maa_pwm_init_raw(int chipid, int pin);
 
 /** Set the ouput duty-cycle percentage, as a float
  *
@@ -76,7 +67,7 @@ maa_pwm_context* maa_pwm_init_raw(int chipid, int pin);
  *
  * @return maa_result_t the maa result.
  */
-maa_result_t maa_pwm_write(maa_pwm_context* pwm, float percentage);
+maa_result_t maa_pwm_write(maa_pwm_context pwm, float percentage);
 
 /** Read the ouput duty-cycle percentage, as a float
  *
@@ -85,7 +76,7 @@ maa_result_t maa_pwm_write(maa_pwm_context* pwm, float percentage);
  *    The value should lie between 0.0f (representing on 0%) and 1.0f
  *    Values above or below this range will be set at either 0.0f or 1.0f.
  */
-float maa_pwm_read(maa_pwm_context* pwm);
+float maa_pwm_read(maa_pwm_context pwm);
 
 /** Set the PWM period as seconds represented in a float
  *
@@ -94,7 +85,7 @@ float maa_pwm_read(maa_pwm_context* pwm);
  *
  * @return maa_result_t the maa result.
  */
-maa_result_t maa_pwm_period(maa_pwm_context* pwm, float seconds);
+maa_result_t maa_pwm_period(maa_pwm_context pwm, float seconds);
 
 /** Set period, milli-oseconds.
  *
@@ -103,7 +94,7 @@ maa_result_t maa_pwm_period(maa_pwm_context* pwm, float seconds);
  *
  * @return maa_result_t the maa result.
  */
-maa_result_t maa_pwm_period_ms(maa_pwm_context* pwm, int ms);
+maa_result_t maa_pwm_period_ms(maa_pwm_context pwm, int ms);
 
 /** Set period, microseconds
  *
@@ -112,7 +103,7 @@ maa_result_t maa_pwm_period_ms(maa_pwm_context* pwm, int ms);
  *
  * @return maa_result_t the maa result.
  */
-maa_result_t maa_pwm_period_us(maa_pwm_context* pwm, int us);
+maa_result_t maa_pwm_period_us(maa_pwm_context pwm, int us);
 
 /** Set pulsewidth, As represnted by seconds in a (float).
  *
@@ -121,7 +112,7 @@ maa_result_t maa_pwm_period_us(maa_pwm_context* pwm, int us);
  *
  * @return maa_result_t the maa result.
  */
-maa_result_t maa_pwm_pulsewidth(maa_pwm_context* pwm, float seconds);
+maa_result_t maa_pwm_pulsewidth(maa_pwm_context pwm, float seconds);
 
 /** Set pulsewidth, milliseconds
  *
@@ -130,7 +121,7 @@ maa_result_t maa_pwm_pulsewidth(maa_pwm_context* pwm, float seconds);
  *
  * @return maa_result_t the maa result.
  */
-maa_result_t maa_pwm_pulsewidth_ms(maa_pwm_context* pwm, int ms);
+maa_result_t maa_pwm_pulsewidth_ms(maa_pwm_context pwm, int ms);
 
 /** Set pulsewidth, microseconds.
  *
@@ -139,7 +130,7 @@ maa_result_t maa_pwm_pulsewidth_ms(maa_pwm_context* pwm, int ms);
  *
  * @return maa_result_t the maa result.
  */
-maa_result_t maa_pwm_pulsewidth_us(maa_pwm_context* pwm, int us);
+maa_result_t maa_pwm_pulsewidth_us(maa_pwm_context pwm, int us);
 
 /** Set the enable status of the PWM pin. None zero will assume on with output being driven.
  *   and 0 will disable the output.
@@ -149,7 +140,7 @@ maa_result_t maa_pwm_pulsewidth_us(maa_pwm_context* pwm, int us);
  *
  * @return maa_result_t the maa result.
  */
-maa_result_t maa_pwm_enable(maa_pwm_context* pwm, int enable);
+maa_result_t maa_pwm_enable(maa_pwm_context pwm, int enable);
 
 /** Unexport the PWM context (maa_pwm_close() will call this function)
  *
@@ -157,7 +148,7 @@ maa_result_t maa_pwm_enable(maa_pwm_context* pwm, int enable);
  *
  * @return maa result type.
  */
-maa_result_t maa_pwm_unexport(maa_pwm_context* pwm);
+maa_result_t maa_pwm_unexport(maa_pwm_context pwm);
 
 /** Close and unexport the PWM pin.
  * 
@@ -165,7 +156,7 @@ maa_result_t maa_pwm_unexport(maa_pwm_context* pwm);
  *
  * @return maa_result_t the maa result.
  */
-maa_result_t maa_pwm_close(maa_pwm_context* pwm);
+maa_result_t maa_pwm_close(maa_pwm_context pwm);
 
 #ifdef __cplusplus
 }

api/pwm.hpp

@@ -0,0 +1,82 @@
+/*
+ * Author: Brendan Le Foll <brendan.le.foll@intel.com>
+ * Copyright (c) 2014 Intel Corporation.
+ *
+ * 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.
+ */
+
+#pragma once
+
+/** @file
+ *
+ * This file defines the pwm C++ interface for libmaa
+ *
+ */
+
+#include "pwm.h"
+
+namespace maa {
+
+class Pwm {
+    public:
+        Pwm(int pin, int chipid=-1) {
+            if (chipid == -1)
+                m_pwm = maa_pwm_init(pin);
+            else
+                m_pwm = maa_pwm_init_raw(pin, chipid);
+        }
+        ~Pwm() {
+            maa_pwm_close(m_pwm);
+        }
+        maa_result_t write(float percentage) {
+            return maa_pwm_write(m_pwm, percentage);
+        }
+        float read() {
+            return maa_pwm_read(m_pwm);
+        }
+        maa_result_t period(float period) {
+            return maa_pwm_period(m_pwm, period);
+        }
+        maa_result_t period_ms(int ms) {
+            return maa_pwm_period_ms(m_pwm, ms);
+        }
+        maa_result_t period_us(int us) {
+            return maa_pwm_period_us(m_pwm, us);
+        }
+        maa_result_t pulsewidth(float seconds) {
+            return maa_pwm_pulsewidth(m_pwm, seconds);
+        }
+        maa_result_t pulsewidth_ms(int ms) {
+            return maa_pwm_pulsewidth_ms(m_pwm, ms);
+        }
+        maa_result_t pulsewidth_us(int us) {
+            return maa_pwm_pulsewidth_us(m_pwm, us);
+        }
+        maa_result_t enable(bool enable) {
+            if (enable)
+                return maa_pwm_enable(m_pwm, 1);
+            else
+                return maa_pwm_enable(m_pwm, 0);
+        }
+    private:
+        maa_pwm_context m_pwm;
+};
+
+}

examples/cycle-pwm3.c

@@ -30,7 +30,7 @@ int
 main ()
 {
     maa_init();
-    maa_pwm_context* pwm;
+    maa_pwm_context pwm;
     pwm = maa_pwm_init(3);
     if (pwm == NULL) {
         return 1;

src/CMakeLists.txt

@@ -9,6 +9,7 @@ set (maa_LIB_HEADERS
   ${PROJECT_SOURCE_DIR}/api/i2c.h
   ${PROJECT_SOURCE_DIR}/api/i2c.hpp
   ${PROJECT_SOURCE_DIR}/api/pwm.h
+  ${PROJECT_SOURCE_DIR}/api/pwm.hpp
   ${PROJECT_SOURCE_DIR}/api/spi.h
   ${PROJECT_SOURCE_DIR}/api/aio.h
   ${PROJECT_SOURCE_DIR}/api/aio.hpp

src/maa.i

@@ -1,7 +1,7 @@
 %{
     #include "maa.h"
     #include "gpio.h"
-    #include "pwm.h"
+    #include "pwm.hpp"
     #include "i2c.hpp"
     #include "spi.h"
     #include "aio.hpp"
@@ -130,68 +130,7 @@ typedef struct {
 
 #### PWM ####
 
-%rename(Pwm) maa_pwm_context;
-
-%ignore duty_fp;
-typedef struct {
-    /*@{*/
-    int pin; /**< the pin number, as known to the os. */
-    int chipid; /**< the chip id, which the pwm resides */
-    FILE *duty_fp; /**< File pointer to duty file */
-    /*@}*/
-} maa_pwm_context;
-
-%nodefault maa_pwm_context;
-%extend maa_pwm_context {
-  maa_pwm_context(int pin)
-  {
-    return maa_pwm_init(pin);
-  }
-  maa_pwm_context(int chipid, int pin)
-  {
-    return maa_pwm_init_raw(chipid, pin);
-  }
-  ~maa_pwm_context()
-  {
-    maa_pwm_unexport($self);
-  }
-  int write(float percentage)
-  {
-    return maa_pwm_write($self, percentage);
-  }
-  int read()
-  {
-    return maa_pwm_read($self);
-  }
-  int period(float seconds)
-  {
-    return maa_pwm_period($self, seconds);
-  }
-  int period_ms(int ms)
-  {
-    return maa_pwm_period_ms($self, ms);
-  }
-  int period_us(int us)
-  {
-    return maa_pwm_period_us($self, us);
-  }
-  int pulsewidth(float seconds)
-  {
-    return maa_pwm_pulsewidth($self, seconds);
-  }
-  int pulsewidth_ms(int ms)
-  {
-    return maa_pwm_pulsewidth($self, ms);
-  }
-  int pulsewidth_us(int us)
-  {
-    return maa_pwm_pulsewidth($self, us);
-  }
-  int enable(int enable)
-  {
-    return maa_pwm_enable($self, enable);
-  }
-}
+%include "pwm.hpp"
 
 #### SPI ####
 

src/pwm/pwm.c

@@ -26,8 +26,19 @@
 
 #include "pwm.h"
 
+/**
+ * A strucutre representing a PWM pin
+ */
+struct _pwm {
+    /*@{*/
+    int pin; /**< the pin number, as known to the os. */
+    int chipid; /**< the chip id, which the pwm resides */
+    FILE *duty_fp; /**< File pointer to duty file */
+    /*@}*/
+};
+
 static int
-maa_pwm_setup_duty_fp(maa_pwm_context* dev)
+maa_pwm_setup_duty_fp(maa_pwm_context dev)
 {
     char bu[64];
     sprintf(bu, "/sys/class/pwm/pwmchip%d/pwm%d/duty_cycle", dev->chipid, dev->pin);
@@ -39,7 +50,7 @@ maa_pwm_setup_duty_fp(maa_pwm_context* dev)
 }
 
 static maa_result_t
-maa_pwm_write_period(maa_pwm_context* dev, int period)
+maa_pwm_write_period(maa_pwm_context dev, int period)
 {
     FILE *period_f;
     char bu[64];
@@ -57,7 +68,7 @@ maa_pwm_write_period(maa_pwm_context* dev, int period)
 }
 
 static maa_result_t
-maa_pwm_write_duty(maa_pwm_context* dev, int duty)
+maa_pwm_write_duty(maa_pwm_context dev, int duty)
 {
     if (dev->duty_fp == NULL) {
         maa_pwm_setup_duty_fp(dev);
@@ -71,7 +82,7 @@ maa_pwm_write_duty(maa_pwm_context* dev, int duty)
 }
 
 static int
-maa_pwm_get_period(maa_pwm_context* dev)
+maa_pwm_get_period(maa_pwm_context dev)
 {
     FILE *period_f;
     char bu[64];
@@ -88,7 +99,7 @@ maa_pwm_get_period(maa_pwm_context* dev)
 }
 
 static int
-maa_pwm_get_duty(maa_pwm_context* dev)
+maa_pwm_get_duty(maa_pwm_context dev)
 {
     if (dev->duty_fp == NULL) {
         maa_pwm_setup_duty_fp(dev);
@@ -99,7 +110,7 @@ maa_pwm_get_duty(maa_pwm_context* dev)
     return atoi(output);
 }
 
-maa_pwm_context*
+maa_pwm_context
 maa_pwm_init(int pin) {
     maa_pin_t* pinm = maa_check_pwm(pin);
     if (pinm == NULL)
@@ -110,10 +121,10 @@ maa_pwm_init(int pin) {
     return maa_pwm_init_raw(chip,pinn);
 }
 
-maa_pwm_context*
+maa_pwm_context
 maa_pwm_init_raw(int chipin, int pin)
 {
-    maa_pwm_context* dev = (maa_pwm_context*) malloc(sizeof(maa_pwm_context));
+    maa_pwm_context dev = (maa_pwm_context) malloc(sizeof(struct _pwm));
     if (dev == NULL)
         return NULL;
 
@@ -137,56 +148,56 @@ maa_pwm_init_raw(int chipin, int pin)
 }
 
 maa_result_t
-maa_pwm_write(maa_pwm_context* dev, float percentage)
+maa_pwm_write(maa_pwm_context dev, float percentage)
 {
    return maa_pwm_write_duty(dev, percentage * maa_pwm_get_period(dev));
 }
 
 float
-maa_pwm_read(maa_pwm_context* dev)
+maa_pwm_read(maa_pwm_context dev)
 {
     float output = maa_pwm_get_duty(dev) / (float) maa_pwm_get_period(dev);
     return output;
 }
 
 maa_result_t
-maa_pwm_period(maa_pwm_context* dev, float seconds)
+maa_pwm_period(maa_pwm_context dev, float seconds)
 {
     return maa_pwm_period_ms(dev, seconds*1000);
 }
 
 maa_result_t
-maa_pwm_period_ms(maa_pwm_context* dev, int ms)
+maa_pwm_period_ms(maa_pwm_context dev, int ms)
 {
     return maa_pwm_period_us(dev, ms*1000);
 }
 
 maa_result_t
-maa_pwm_period_us(maa_pwm_context* dev, int us)
+maa_pwm_period_us(maa_pwm_context dev, int us)
 {
     return maa_pwm_write_period(dev, us*1000);
 }
 
 maa_result_t
-maa_pwm_pulsewidth(maa_pwm_context* dev, float seconds)
+maa_pwm_pulsewidth(maa_pwm_context dev, float seconds)
 {
     return maa_pwm_pulsewidth_ms(dev, seconds*1000);
 }
 
 maa_result_t
-maa_pwm_pulsewidth_ms(maa_pwm_context* dev, int ms)
+maa_pwm_pulsewidth_ms(maa_pwm_context dev, int ms)
 {
     return maa_pwm_pulsewidth_us(dev, ms*1000);
 }
 
 maa_result_t
-maa_pwm_pulsewidth_us(maa_pwm_context* dev, int us)
+maa_pwm_pulsewidth_us(maa_pwm_context dev, int us)
 {
     return maa_pwm_write_duty(dev, us*1000);
 }
 
 maa_result_t
-maa_pwm_enable(maa_pwm_context* dev, int enable)
+maa_pwm_enable(maa_pwm_context dev, int enable)
 {
     int status;
     if (enable != 0) {
@@ -210,7 +221,7 @@ maa_pwm_enable(maa_pwm_context* dev, int enable)
 }
 
 maa_result_t
-maa_pwm_unexport(maa_pwm_context* dev)
+maa_pwm_unexport(maa_pwm_context dev)
 {
     // disable pwm before unexporting
     maa_pwm_enable(dev, 0);
@@ -230,7 +241,7 @@ maa_pwm_unexport(maa_pwm_context* dev)
 }
 
 maa_result_t
-maa_pwm_close(maa_pwm_context* dev)
+maa_pwm_close(maa_pwm_context dev)
 {
     maa_pwm_unexport(dev);
     free(dev);