Diff: DigitalInOut.h

Revision:

122:f9eeca106725

Parent:

93:e188a91d3eaa

Child:

123:b0220dba8be7

--- a/DigitalInOut.h	Wed May 25 16:44:06 2016 +0100
+++ b/DigitalInOut.h	Thu Jul 07 14:34:11 2016 +0100
@@ -19,10 +19,13 @@
 #include "platform.h"
 
 #include "gpio_api.h"
+#include "critical.h"
 
 namespace mbed {
 
 /** A digital input/output, used for setting or reading a bi-directional pin
+ *
+ * @Note Synchronization level: Interrupt safe
  */
 class DigitalInOut {
 
@@ -32,6 +35,7 @@
      *  @param pin DigitalInOut pin to connect to
      */
     DigitalInOut(PinName pin) : gpio() {
+        // No lock needed in the constructor
         gpio_init_in(&gpio, pin);
     }
 
@@ -43,6 +47,7 @@
      *  @param value the initial value of the pin if is an output
      */
     DigitalInOut(PinName pin, PinDirection direction, PinMode mode, int value) : gpio() {
+        // No lock needed in the constructor
         gpio_init_inout(&gpio, pin, direction, mode, value);
     }
 
@@ -52,6 +57,7 @@
      *      0 for logical 0, 1 (or any other non-zero value) for logical 1
      */
     void write(int value) {
+        // Thread safe / atomic HAL call
         gpio_write(&gpio, value);
     }
 
@@ -62,19 +68,24 @@
      *    or read the input if set as an input
      */
     int read() {
+        // Thread safe / atomic HAL call
         return gpio_read(&gpio);
     }
 
     /** Set as an output
      */
     void output() {
+        core_util_critical_section_enter();
         gpio_dir(&gpio, PIN_OUTPUT);
+        core_util_critical_section_exit();
     }
 
     /** Set as an input
      */
     void input() {
+        core_util_critical_section_enter();
         gpio_dir(&gpio, PIN_INPUT);
+        core_util_critical_section_exit();
     }
 
     /** Set the input pin mode
@@ -82,7 +93,9 @@
      *  @param mode PullUp, PullDown, PullNone, OpenDrain
      */
     void mode(PinMode pull) {
+        core_util_critical_section_enter();
         gpio_mode(&gpio, pull);
+        core_util_critical_section_exit();
     }
 
     /** Return the output setting, represented as 0 or 1 (int)
@@ -92,6 +105,7 @@
      *    0 if gpio object was initialized with NC
      */
     int is_connected() {
+        // Thread safe / atomic HAL call
         return gpio_is_connected(&gpio);
     }
 
@@ -99,18 +113,22 @@
     /** A shorthand for write()
      */
     DigitalInOut& operator= (int value) {
+        // Underlying write is thread safe
         write(value);
         return *this;
     }
 
     DigitalInOut& operator= (DigitalInOut& rhs) {
+        core_util_critical_section_enter();
         write(rhs.read());
+        core_util_critical_section_exit();
         return *this;
     }
 
     /** A shorthand for read()
      */
     operator int() {
+        // Underlying call is thread safe
         return read();
     }
 #endif