rockbox/firmware/target/arm/imx233/pwm-imx233.h
Amaury Pouly f8d2984875 imx233: enhance pwm
The current pwm interface is too low-level. Introduce a higher
level setup function which directly computes the parameters from
the required frequency.

Change-Id: Ie95c7522e9f42492fe872203f4cab46770a9649a
2013-06-17 00:29:24 +02:00

58 lines
2.1 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2011 by Amaury Pouly
*
* This program 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef __PWM_IMX233_H__
#define __PWM_IMX233_H__
#include "system.h"
#include "regs/regs-pwm.h"
/* fake field for simpler programming */
#define BP_PWM_CTRL_PWMx_ENABLE(x) (x)
#define BM_PWM_CTRL_PWMx_ENABLE(x) (1 << (x))
#define IMX233_PWM_MAX_PERIOD (1 << 16)
#define IMX233_PWM_NR_CHANNELS 5
void imx233_pwm_init(void);
void imx233_pwm_setup(int channel, int period, int cdiv, int active,
int active_state, int inactive, int inactive_state);
/* helper function to compute adequate divisor and period, given a minimum
* period resolution (for active/inactive) */
void imx233_pwm_lookup_freq(int freq, int min_period, int *period, int *cdiv);
/* simple setup with active 1, inactive 0, duty cycle in percent */
void imx233_pwm_setup_simple(int channel, int freq, int duty_cycle);
void imx233_pwm_enable(int channel, bool enable);
bool imx233_pwm_is_enabled(int channel);
struct imx233_pwm_info_t
{
bool enabled;
int cdiv;
int period;
int inactive, active;
char inactive_state, active_state; // '0', '1' or 'Z'
};
struct imx233_pwm_info_t imx233_pwm_get_info(int channel);
#endif /* __PWM_IMX233_H__ */