1 files changed, 50 insertions, 12 deletions
diff --git a/os/hal/src/pwm.c b/os/hal/src/pwm.c
index cf619e508..e7dd6b64c 100644
--- a/os/hal/src/pwm.c
+++ b/os/hal/src/pwm.c
@@ -1,5 +1,6 @@
 /*
-    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010 Giovanni Di Sirio.
+    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
+                 2011 Giovanni Di Sirio.
 
     This file is part of ChibiOS/RT.
 
@@ -67,8 +68,8 @@ void pwmInit(void) {
  */
 void pwmObjectInit(PWMDriver *pwmp) {
 
-  pwmp->pd_state    = PWM_STOP;
-  pwmp->pd_config   = NULL;
+  pwmp->state    = PWM_STOP;
+  pwmp->config   = NULL;
 #if defined(PWM_DRIVER_EXT_INIT_HOOK)
   PWM_DRIVER_EXT_INIT_HOOK(pwmp);
 #endif
@@ -76,6 +77,8 @@ void pwmObjectInit(PWMDriver *pwmp) {
 
 /**
  * @brief   Configures and activates the PWM peripheral.
+ * @note    Starting a driver that is already in the @p PWM_READY state
+ *          disables all the active channels.
  *
  * @param[in] pwmp      pointer to a @p PWMDriver object
  * @param[in] config    pointer to a @p PWMConfig object
@@ -87,11 +90,12 @@ void pwmStart(PWMDriver *pwmp, const PWMConfig *config) {
   chDbgCheck((pwmp != NULL) && (config != NULL), "pwmStart");
 
   chSysLock();
-  chDbgAssert((pwmp->pd_state == PWM_STOP) || (pwmp->pd_state == PWM_READY),
+  chDbgAssert((pwmp->state == PWM_STOP) || (pwmp->state == PWM_READY),
               "pwmStart(), #1", "invalid state");
-  pwmp->pd_config = config;
+  pwmp->config = config;
+  pwmp->period = config->period;
   pwm_lld_start(pwmp);
-  pwmp->pd_state = PWM_READY;
+  pwmp->state = PWM_READY;
   chSysUnlock();
 }
 
@@ -107,16 +111,46 @@ void pwmStop(PWMDriver *pwmp) {
   chDbgCheck(pwmp != NULL, "pwmStop");
 
   chSysLock();
-  chDbgAssert((pwmp->pd_state == PWM_STOP) || (pwmp->pd_state == PWM_READY),
+  chDbgAssert((pwmp->state == PWM_STOP) || (pwmp->state == PWM_READY),
               "pwmStop(), #1", "invalid state");
   pwm_lld_stop(pwmp);
-  pwmp->pd_state = PWM_STOP;
+  pwmp->state = PWM_STOP;
+  chSysUnlock();
+}
+
+/**
+ * @brief   Changes the period the PWM peripheral.
+ * @details This function changes the period of a PWM unit that has already
+ *          been activated using @p pwmStart().
+ * @pre     The PWM unit must have been activated using @p pwmStart().
+ * @post    The PWM unit period is changed to the new value.
+ * @note    If a period is specified that is shorter than the pulse width
+ *          programmed in one of the channels then the behavior is not
+ *          guaranteed.
+ *
+ * @param[in] pwmp      pointer to a @p PWMDriver object
+ * @param[in] period    new cycle time in ticks
+ *
+ * @api
+ */
+void pwmChangePeriod(PWMDriver *pwmp, pwmcnt_t period) {
+
+  chDbgCheck(pwmp != NULL, "pwmChangePeriod");
+
+  chSysLock();
+  chDbgAssert(pwmp->state == PWM_READY,
+              "pwmChangePeriod(), #1", "invalid state");
+  pwmChangePeriodI(pwmp, period);
   chSysUnlock();
 }
 
 /**
  * @brief   Enables a PWM channel.
- * @details Programs (or reprograms) a PWM channel.
+ * @pre     The PWM unit must have been activated using @p pwmStart().
+ * @post    The channel is active using the specified configuration.
+ * @note    Depending on the hardware implementation this function has
+ *          effect starting on the next cycle (recommended implementation)
+ *          or immediately (fallback implementation).
  *
  * @param[in] pwmp      pointer to a @p PWMDriver object
  * @param[in] channel   PWM channel identifier (0...PWM_CHANNELS-1)
@@ -132,7 +166,7 @@ void pwmEnableChannel(PWMDriver *pwmp,
              "pwmEnableChannel");
 
   chSysLock();
-  chDbgAssert(pwmp->pd_state == PWM_READY,
+  chDbgAssert(pwmp->state == PWM_READY,
               "pwmEnableChannel(), #1", "not ready");
   pwm_lld_enable_channel(pwmp, channel, width);
   chSysUnlock();
@@ -140,8 +174,12 @@ void pwmEnableChannel(PWMDriver *pwmp,
 
 /**
  * @brief   Disables a PWM channel.
- * @details The channel is disabled and its output line returned to the
+ * @pre     The PWM unit must have been activated using @p pwmStart().
+ * @post    The channel is disabled and its output line returned to the
  *          idle state.
+ * @note    Depending on the hardware implementation this function has
+ *          effect starting on the next cycle (recommended implementation)
+ *          or immediately (fallback implementation).
  *
  * @param[in] pwmp      pointer to a @p PWMDriver object
  * @param[in] channel   PWM channel identifier (0...PWM_CHANNELS-1)
@@ -154,7 +192,7 @@ void pwmDisableChannel(PWMDriver *pwmp, pwmchannel_t channel) {
              "pwmEnableChannel");
 
   chSysLock();
-  chDbgAssert(pwmp->pd_state == PWM_READY,
+  chDbgAssert(pwmp->state == PWM_READY,
               "pwmDisableChannel(), #1", "not ready");
   pwm_lld_disable_channel(pwmp, channel);
   chSysUnlock();