*
* \brief PWM driver (implementation)
*
- * \version $Id$
*
* \author Francesco Sacchi <batt@develer.com>
* \author Daniele Basile <asterix@develer.com>
#include "cfg/cfg_pwm.h"
#include <cfg/macros.h>
+#include <cfg/module.h>
// Define logging setting (for cfg/log.h module).
#define LOG_LEVEL PWM_LOG_LEVEL
#include <cpu/types.h>
#include <cpu/irq.h>
-
-/**
- * Set duty of pwm channel \p dev.
- */
-void pwm_setDuty(PwmDev dev, pwm_duty_t duty)
-{
- pwm_period_t period = 0;
- pwm_duty_t real_duty = 0;
-
- duty = MIN(duty, PWM_MAX_DUTY);
-
- period = pwm_hw_getPeriod(dev);
-
- real_duty = (uint64_t)(duty * period) >> (uint64_t)PWM_MAX_PERIOD_LOG2;
-
- LOG_INFO("real_duty[%d] duty[%d], period[%d]", real_duty, duty, period);
- pwm_hw_setDutyUnlock(dev, real_duty);
-}
-
-/**
- * Set frequency of pwm channel \p dev at \p freq in Hz.
- */
-void pwm_setFrequency(PwmDev dev, pwm_freq_t freq)
-{
- pwm_hw_setFrequency(dev, freq);
-}
-
-/**
- * Set duty of pwm channel \p dev.
- */
-void pwm_enable(PwmDev dev, bool state)
-{
- if (state)
- pwm_hw_enable(dev);
- else
- pwm_hw_disable(dev);
-}
-
-/**
- * Initialize PWM hw.
- */
-void pwm_init(void)
-{
- cpu_flags_t flags;
- PwmDev dev;
-
- IRQ_SAVE_DISABLE(flags);
-
- pwm_hw_init();
-
- /* set all pwm to 0 */
- for (dev = 0; dev < PWM_CNT; dev++)
- pwm_setDuty(dev, 0);
-
- IRQ_RESTORE(flags);
-}
-
-
+#include <string.h>
+
+#if CFG_PWM_ENABLE_OLD_API
+
+ /**
+ * Set duty of PWM channel \p dev.
+ * The current output frequency will be maintained.
+ * \param dev PWM channel.
+ * \param duty the new duty cycle.
+ */
+ void pwm_setDuty(PwmDev dev, pwm_duty_t duty)
+ {
+ pwm_period_t period = 0;
+ pwm_duty_t real_duty = 0;
+
+ duty = MIN(duty, PWM_MAX_DUTY);
+
+ period = pwm_hw_getPeriod(dev);
+
+ real_duty = (uint64_t)(duty * period) >> (uint64_t)PWM_MAX_PERIOD_LOG2;
+
+ LOG_INFO("real_duty[%d] duty[%d], period[%d]\n", real_duty, duty, period);
+ pwm_hw_setDutyUnlock(dev, real_duty);
+ }
+
+ /**
+ * Set frequency of PWM channel \p dev at \p freq.
+ * \param dev PWM channel.
+ * \param freq new frequency, in Hz.
+ * \warning This function has to be called with PWM disabled, otherwise
+ * the output value will be undefined.
+ * The current duty cycle value will be lost, after calling this
+ * function the duty cycle have to be set again.
+ */
+ void pwm_setFrequency(PwmDev dev, pwm_freq_t freq)
+ {
+ pwm_hw_setFrequency(dev, freq);
+ }
+
+ /**
+ * Enable/Disable PWM channel \p dev.
+ * \param dev PWM channel.
+ * \param state if true the PWM on \p dev is activated, if false is disabled.
+ */
+ void pwm_enable(PwmDev dev, bool state)
+ {
+ if (state)
+ pwm_hw_enable(dev);
+ else
+ pwm_hw_disable(dev);
+ }
+
+ MOD_DEFINE(pwm);
+
+ /**
+ * Initialize the PWM driver.
+ * \warning all available PWM channels are initialized.
+ */
+ void pwm_init(void)
+ {
+ cpu_flags_t flags;
+ PwmDev dev;
+
+ IRQ_SAVE_DISABLE(flags);
+
+ pwm_hw_init();
+
+ /* set all pwm to 0 */
+ for (dev = 0; dev < PWM_CNT; dev++)
+ pwm_setDuty(dev, 0);
+
+ IRQ_RESTORE(flags);
+ MOD_INIT(pwm);
+ }
+#endif
+
+#if !CFG_PWM_ENABLE_OLD_API || defined(__doxygen__)
+
+ INLINE void setRealDuty(Pwm *ctx, pwm_duty_t duty)
+ {
+ if (ctx->pol == PWM_POL_LOW_PULSE)
+ duty = PWM_MAX_DUTY - duty;
+
+ pwm_hwreg_t period = pwm_hw_getPeriod(ctx);
+ pwm_hwreg_t hw_duty;
+
+ switch (duty)
+ {
+ case 0:
+ hw_duty = 0;
+ break;
+ case PWM_MAX_DUTY:
+ hw_duty = period;
+ break;
+ default:
+ hw_duty = (uint64_t)(duty * period) >> (uint64_t)PWM_MAX_PERIOD_LOG2;
+ }
+
+ pwm_hw_setDuty(ctx, hw_duty);
+ }
+
+ /**
+ * Set the duty cycle of the PWM channel linked to \p ctx.
+ * The modification will be applied to the channel immediatly.
+ * The current frequency of the channel will be maintained.
+ * \param ctx PWM channel context.
+ * \param duty the new duty cycle value.
+ * \see pwm_duty_t
+ */
+ void pwm_setDuty(Pwm *ctx, pwm_duty_t duty)
+ {
+ ctx->duty = duty;
+
+ if (ctx->enabled)
+ setRealDuty(ctx, duty);
+ }
+
+ /**
+ * Set PWM frequency of channel linked to \p ctx.
+ * The modification will be applied to the channel immediatly.
+ * The duty cycle of the channel will be maintained.
+ * \param ctx PWM channel context.
+ * \param freq the new frequency of the signal, in Hz.
+ * \note Depending on the hardware implementation, this function may
+ * generate a glitch in the output signal upon frequency changing.
+ */
+ void pwm_setFrequency(Pwm *ctx, pwm_freq_t freq)
+ {
+ pwm_hw_setFrequency(ctx, freq);
+ pwm_enable(ctx, ctx->enabled);
+ }
+
+ /**
+ * Set PWM polarity of pwm channel linked to \p ctx.
+ * The modification will be applied to the channel immediatly.
+ * \param ctx PWM channel context.
+ * \param pol the new polarity of the signal.
+ *
+ * \note if a channel is disabled, changing its polarity will change the
+ * current steady output level.
+ * \see pwm_enable
+ * \see PwmPolarity
+ */
+ void pwm_setPolarity(Pwm *ctx, PwmPolarity pol)
+ {
+ ctx->pol = pol;
+ pwm_enable(ctx, ctx->enabled);
+ }
+
+ /**
+ * Enable/Disable the pwm channel linked to \p ctx.
+ * The modification will be applied to the channel immediatly.
+ * \param ctx PWM channel context.
+ * \param enable if true the channel will be enabled, if false will be disabled.
+ *
+ * \note When a PWM channel is disabled, the output level will be the same
+ * as if the duty would be set to 0%.
+ * So, if current polarity is positive, a disabled channel will be
+ * low, if polarity is negative will be high.
+ * \see pwm_setPolarity
+ */
+ void pwm_enable(Pwm *ctx, bool enable)
+ {
+ ctx->enabled = enable;
+
+ if (enable)
+ setRealDuty(ctx, ctx->duty);
+ else
+ setRealDuty(ctx, 0);
+ }
+
+ /**
+ * Initialize PWM driver.
+ * \param ctx pointer to a PWM context structure, used for holding PWM
+ * driver related information.
+ * \param channel the channel you want to initialize.
+ * \note The channel will be initialized disabled and with High polarity.
+ */
+ void pwm_init(Pwm *ctx, unsigned channel)
+ {
+ memset(ctx, 0, sizeof(*ctx));
+ ctx->ch = channel;
+
+ pwm_hw_init(ctx, channel);
+ }
+
+#endif
projects / bertos.git / blobdiff