Add pwm driver.

git-svn-id: https://src.develer.com/svnoss/bertos/trunk@1235 38d2e660-2303-0410-9eaa-f027e97ec537

diff --git a/bertos/cpu/arm/drv/pwm_at91.c b/bertos/cpu/arm/drv/pwm_at91.c
new file mode 100644 (file)
index 0000000..b1fda46
--- /dev/null
+++ b/bertos/cpu/arm/drv/pwm_at91.c
@@ -0,0 +1,216 @@
+/**
+ * \file
+ * <!--
+ * This file is part of BeRTOS.
+ *
+ * Bertos is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * As a special exception, you may use this file as part of a free software
+ * library without restriction.  Specifically, if other files instantiate
+ * templates or use macros or inline functions from this file, or you compile
+ * this file and link it with other files to produce an executable, this
+ * file does not by itself cause the resulting executable to be covered by
+ * the GNU General Public License.  This exception does not however
+ * invalidate any other reasons why the executable file might be covered by
+ * the GNU General Public License.
+ *
+ * Copyright 2008 Develer S.r.l. (http://www.develer.com/)
+ *
+ * -->
+ *
+ *
+ * \brief PWM hardware-specific implementation
+ *
+ * \version $Id$
+ *
+ * \author Daniele Basile <asterix@develer.com>
+ */
+
+#include "pwm_at91.h"
+
+#include <hw/hw_cpu.h>
+
+#include <cfg/macros.h>
+#include <cfg/debug.h>
+#include <io/arm.h>
+
+#include "appconfig.h"
+
+/**
+ * Register structure for pwm driver.
+ * This array content all data and register pointer
+ * to manage pwm peripheral device.
+ */
+static PwmChannel pwm_map[PWM_CNT] =
+{
+       {//PWM Channel 0
+               .duty_zero = false,
+               .pwm_pin = BV(PWM0),
+               .mode_reg = &PWM_CMR0,
+               .duty_reg = &PWM_CDTY0,
+               .period_reg = &PWM_CPRD0,
+               .update_reg = &PWM_CUPD0,
+       },
+       {//PWM Channel 1
+               .duty_zero = false,
+               .pwm_pin = BV(PWM1),
+               .mode_reg = &PWM_CMR1,
+               .duty_reg = &PWM_CDTY1,
+               .period_reg = &PWM_CPRD1,
+               .update_reg = &PWM_CUPD1,
+       },
+       {//PWM Channel 2
+               .duty_zero = false,
+               .pwm_pin = BV(PWM2),
+               .mode_reg = &PWM_CMR2,
+               .duty_reg = &PWM_CDTY2,
+               .period_reg = &PWM_CPRD2,
+               .update_reg = &PWM_CUPD2,
+       },
+       {//PWM Channel 3
+               .duty_zero = false,
+               .pwm_pin = BV(PWM3),
+               .mode_reg = &PWM_CMR3,
+               .duty_reg = &PWM_CDTY3,
+               .period_reg = &PWM_CPRD3,
+               .update_reg = &PWM_CUPD3,
+       }
+};
+
+
+/**
+ * Get preiod from select channel
+ *
+ * \a dev channel
+ */
+pwm_period_t pwm_hw_getPeriod(PwmDev dev)
+{
+       return *pwm_map[dev].period_reg;
+}
+
+/**
+ * Set pwm waveform frequecy.
+ *
+ * \a freq in Hz
+ */
+void pwm_hw_setFrequency(PwmDev dev, uint32_t freq)
+{
+       uint32_t period = 0;
+
+       for(int i = 0; i <= PWM_HW_MAX_PRESCALER_STEP; i++)
+       {
+               period = CLOCK_FREQ / (BV(i) * freq);
+//             TRACEMSG("period[%d], prescale[%d]", period, i);
+               if ((period < PWM_HW_MAX_PERIOD) && (period != 0))
+               {
+                       //Clean previous channel prescaler, and set new
+                       *pwm_map[dev].mode_reg &= ~PWM_CPRE_MCK_MASK;
+                       *pwm_map[dev].mode_reg |= i;
+                       //Set pwm period
+                       *pwm_map[dev].period_reg = period;
+                       break;
+               }
+       }
+
+       PWM_ENA = BV(dev);
+
+//     TRACEMSG("PWM ch[%d] period[%d]", dev, period);
+}
+
+/**
+ * Set pwm duty cycle.
+ *
+ * \a duty value 0 - 2^16
+ */
+void pwm_hw_setDutyUnlock(PwmDev dev, uint16_t duty)
+{
+       ASSERT(duty <= (uint16_t)*pwm_map[dev].period_reg);
+
+
+       /*
+        * WARNING: is forbidden to write 0 to duty cycle value,
+        * and so for duty = 0 we must enable PIO and clear output!
+        */
+       if (!duty)
+       {
+               PWM_PIO_PER = pwm_map[dev].pwm_pin;
+               pwm_map[dev].duty_zero = true;
+       }
+       else
+       {
+               ASSERT(PWM_CCNT0);
+               PWM_PIO_PDR = pwm_map[dev].pwm_pin;
+               *pwm_map[dev].update_reg = duty;
+               pwm_map[dev].duty_zero = false;
+       }
+
+//     TRACEMSG("PWM ch[%d] duty[%d], period[%ld]", dev, duty, *pwm_map[dev].period_reg);
+}
+
+
+/**
+ * Enable select pwm channel
+ */
+void pwm_hw_enable(PwmDev dev)
+{
+       if (!pwm_map[dev].duty_zero)
+               PWM_PIO_PDR = pwm_map[dev].pwm_pin;
+}
+
+/**
+ * Disable select pwm channel
+ */
+void pwm_hw_disable(PwmDev dev)
+{
+       PWM_PIO_PER = pwm_map[dev].pwm_pin;
+}
+
+
+/**
+ * Init pwm.
+ */
+void pwm_hw_init(void)
+{
+
+       /*
+        * Init pwm:
+        * WARNING: is forbidden to write 0 to duty cycle value,
+        * and so for duty = 0 we must enable PIO and clear output!
+        * - clear PIO outputs
+        * - enable PIO outputs
+        * - Disable PIO and enable PWM functions
+        * - Power on PWM
+        */
+       PWM_PIO_CODR = BV(PWM0) | BV(PWM1) | BV(PWM2) | BV(PWM3);
+       PWM_PIO_OER = BV(PWM0) | BV(PWM1) | BV(PWM2) | BV(PWM3);
+       PWM_PIO_PDR = BV(PWM0) | BV(PWM1) | BV(PWM2) | BV(PWM3);
+       PWM_PIO_ABSR = BV(PWM0) | BV(PWM1) | BV(PWM2) | BV(PWM3);
+       PMC_PCER |= BV(PWMC_ID);
+
+       /* Disable all channels. */
+       PWM_DIS = 0xFFFFFFFF;
+       /* Disable prescalers A and B */
+       PWM_MR = 0;
+
+       /*
+        * Set pwm mode:
+        * - set period alidned to left
+        * - set output waveform to low level
+        * - allow duty cycle modify at next period event
+        */
+       for (int ch = 0; ch < PWM_CNT; ch++)
+               *pwm_map[ch].mode_reg = 0;
+}
+

diff --git a/bertos/cpu/arm/drv/pwm_at91.h b/bertos/cpu/arm/drv/pwm_at91.h
new file mode 100644 (file)
index 0000000..50cac04
--- /dev/null
+++ b/bertos/cpu/arm/drv/pwm_at91.h
@@ -0,0 +1,83 @@
+/**
+ * \file
+ * <!--
+ * This file is part of BeRTOS.
+ *
+ * Bertos is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * As a special exception, you may use this file as part of a free software
+ * library without restriction.  Specifically, if other files instantiate
+ * templates or use macros or inline functions from this file, or you compile
+ * this file and link it with other files to produce an executable, this
+ * file does not by itself cause the resulting executable to be covered by
+ * the GNU General Public License.  This exception does not however
+ * invalidate any other reasons why the executable file might be covered by
+ * the GNU General Public License.
+ *
+ * Copyright 2008 Develer S.r.l. (http://www.develer.com/)
+ *
+ * -->
+ *
+ *
+ * \brief PWM hardware-specific definition
+ *
+ * \version $Id$
+ *
+ * \author Daniele Basile <asterix@develer.com>
+ */
+
+#ifndef DRV_PWM_AT91_H
+#define DRV_PWM_AT91_H
+
+#include <hw/pwm_map.h>
+
+#include <cfg/compiler.h>
+#include <cfg/macros.h>
+
+#include <io/arm.h>
+
+#include "appconfig.h"
+
+#define PWM_HW_MAX_PRESCALER_STEP         10
+#define PWM_HW_MAX_PERIOD             0xFFFF
+
+/**
+ * Type definition for pwm period.
+ */
+typedef uint16_t pwm_period_t;
+
+/**
+ * Structur definition for pwm driver.
+ */
+typedef struct PwmChannel
+{
+       bool duty_zero;         ///< True if duty cyle is zero, false otherwise.
+       int pwm_pin;            ///< PWM pin.
+       reg32_t *mode_reg;      ///< PWM mode register.
+       reg32_t *duty_reg;      ///< PWM duty cycle register.
+       reg32_t *period_reg;    ///< PWM periodic register.
+       reg32_t *update_reg;    ///< Update setting register for PWM.
+
+} PwmChannel;
+
+
+void pwm_hw_init(void);
+void pwm_hw_setFrequency(PwmDev dev, uint32_t freq);
+void pwm_hw_setDutyUnlock(PwmDev dev, uint16_t duty);
+void pwm_hw_disable(PwmDev dev);
+void pwm_hw_enable(PwmDev dev);
+pwm_period_t pwm_hw_getPeriod(PwmDev dev);
+
+#endif /* DRV_ADC_AT91_H */