X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=bertos%2Fdrv%2Fpwm.h;h=4ed32f85183d576126b2b715996d073999690bb9;hb=e8b0472be10fba4ca6baa62d8d483db90e28c06e;hp=60ae6e922e4bfee52c7d7e6304f0acb9c39262b6;hpb=22b1f5f85862e7cd4a67addf4737a74b1dd30a0b;p=bertos.git

diff --git a/bertos/drv/pwm.h b/bertos/drv/pwm.h
index 60ae6e92..4ed32f85 100644
--- a/bertos/drv/pwm.h
+++ b/bertos/drv/pwm.h
@@ -28,8 +28,9 @@
  *
  * Copyright 2005 Develer S.r.l. (http://www.develer.com/)
  * -->
- *
- *
+ * \defgroup pwm_driver PWM driver
+ * \ingroup drivers
+ * \{
  * \brief Pulse Width Modulation (PWM) driver.
  *
  * \author Francesco Sacchi <batt@develer.com>
@@ -44,41 +45,123 @@
 #ifndef DRV_PWM_H
 #define DRV_PWM_H
 
-#include "hw/pwm_map.h"
-
 #include <cpu/attr.h>
 
-#include CPU_HEADER(pwm)
-
 #include <cfg/compiler.h>
+#include "cfg/cfg_pwm.h"
 
+/**
+ * Maximum PWM duty cycle value (100%)
+ */
 #define PWM_MAX_DUTY              ((pwm_duty_t)0xFFFF)
 #define PWM_MAX_PERIOD                         0xFFFF
 #define PWM_MAX_PERIOD_LOG2                        16
 
 /**
- * PWM type define.
+ * Type for PWM duty cycle.
+ * The value is represented as a 16bit unsigned integer, so it ranges from 0 (0%)
+ * to PWM_MAX_DUTY (0xFFFF = 100%).
  */
 typedef uint16_t pwm_duty_t;
+
+/**
+ * Type for PWM frequency.
+ * Unit of measure is Hz.
+ */
 typedef uint32_t pwm_freq_t;
 
+#if !CFG_PWM_ENABLE_OLD_API || defined(__doxygen__)
+	/**
+	 * \defgroup pwm_api PWM API
+	 * With this driver you can control a device with multiple PWM channels.
+	 * You can enable/disable each channel indipendently and also set frequency
+	 * and duty cycle.
+	 *
+	 * API usage example:
+	 * \code
+	 * Pwm pwm; // declare a context structure
+	 * pwm_init(&pwm, 0); // init pwm channel 0
+	 * pwm_setFrequency(&pwm, 1000); // Set frequency of channel 0 to 1000Hz
+	 * pwm_setDuty(&pwm, 0x7FFF); // Set duty to 50% (0xFFFF/2)
+	 * pwm_enable(&pwm, true); // Activate the output
+	 * \endcode
+	 * \{
+	 */
 
+	/**
+	 * Enum describing PWM polarities.
+	 */
+	typedef enum PwmPolarity
+	{
+		/** High pulse: increasing duty increases the part of the signal at high level. */
+		PWM_POL_HIGH_PULSE,
+		/** Positive pulse: same as High pulse. */
+		PWM_POL_POSITIVE = PWM_POL_HIGH_PULSE,
+		/** Low pulse: increasing duty increases the part of the signal at low level. */
+		PWM_POL_LOW_PULSE,
+		/** Negative pulse: same as Low pulse. */
+		PWM_POL_NEGATIVE = PWM_POL_LOW_PULSE,
+	} PwmPolarity;
 
-/**
- * Set PWM polarity of pwm \p dev.
- */
-INLINE void pwm_setPolarity(PwmDev dev, bool pol)
-{
-    pwm_hw_setPolarity(dev, pol);
-}
+	struct PwmHardware; //Fwd declaration
 
-void pwm_setDuty(PwmDev dev, pwm_duty_t duty);
-void pwm_setFrequency(PwmDev dev, pwm_freq_t freq);
-void pwm_setPolarity(PwmDev dev, bool pol);
-void pwm_enable(PwmDev dev, bool state);
-void pwm_init(void);
+	/**
+	 * PWM context structure.
+	 */
+	typedef struct Pwm
+	{
+		unsigned ch;
+		pwm_duty_t duty;
+		PwmPolarity pol;
+		bool enabled;
+		struct PwmHardware *hw;
+	} Pwm;
 
-/**
+	void pwm_setDuty(Pwm *ctx, pwm_duty_t duty);
+	void pwm_setFrequency(Pwm *ctx, pwm_freq_t freq);
+	void pwm_setPolarity(Pwm *ctx, PwmPolarity pol);
+	void pwm_enable(Pwm *ctx, bool state);
+	void pwm_init(Pwm *ctx, unsigned channel);
+	/** \} */ //defgroup pwm_api
+#endif
+
+
+#if CFG_PWM_ENABLE_OLD_API
+	/**
+	 * \defgroup pwm_old_api Old PWM API
+	 * This API has strong limititations, so it has been deprecated.
+	 * It is active by default for backward compatibility reasons, but
+	 * for new projects please use the new PWM API.
+	 * In order to disable this API, check CFG_PWM_ENABLE_OLD_API.
+	 * \see pwm_api
+	 * \see CFG_PWM_ENABLE_OLD_API
+	 * \{
+	 */
+
+	#include CPU_HEADER(pwm)
+	#include "hw/pwm_map.h"
+
+	/**
+	 * Set PWM polarity of pwm \p dev.
+	 * \param dev PWM channel.
+	 * \param pol if false positive polarity pulses are generated,
+	 *            if true negative polarity pulses are generated.
+	 * \warning This function has to be called with PWM disabled, otherwise
+	 *          the output value will be undefined.
+	 */
+	INLINE void pwm_setPolarity(PwmDev dev, bool pol)
+	{
+		pwm_hw_setPolarity(dev, pol);
+	}
+
+	void pwm_setDuty(PwmDev dev, pwm_duty_t duty);
+	void pwm_setFrequency(PwmDev dev, pwm_freq_t freq);
+	void pwm_enable(PwmDev dev, bool state);
+	void pwm_init(void);
+	/** \} */ //defgroup pwm_old_api
+#endif
+
+/*
  * Test function prototypes.
  *
  * See pwm_test.c for implemntation of these functions.
@@ -89,4 +172,7 @@ int pwm_testSetup(void);
 #define pwm_testSetUp() pwm_testSetup()
 int pwm_testTearDown(void);
 
+
+/** \} */ //defgroup pwm_driver
+
 #endif /* DRV_PWM_H */