coreboot-libre-fam15h-rdimm/3rdparty/chromeec/chip/lm4/pwm.c

71 lines
1.6 KiB
C

/* Copyright 2013 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
/* PWM control module for LM4.
*
* On this chip, the PWM logic is implemented by the hardware FAN modules.
*/
#include "clock.h"
#include "fan.h"
#include "gpio.h"
#include "hooks.h"
#include "pwm.h"
#include "pwm_chip.h"
#include "registers.h"
#include "util.h"
void pwm_enable(enum pwm_channel ch, int enabled)
{
fan_set_enabled(pwm_channels[ch].channel, enabled);
}
int pwm_get_enabled(enum pwm_channel ch)
{
return fan_get_enabled(pwm_channels[ch].channel);
}
void pwm_set_duty(enum pwm_channel ch, int percent)
{
if (percent < 0)
percent = 0;
else if (percent > 100)
percent = 100;
/* Assume the fan control is active high and invert it ourselves */
if (pwm_channels[ch].flags & PWM_CONFIG_ACTIVE_LOW)
percent = 100 - percent;
/* Always enable the channel */
pwm_enable(ch, 1);
/* Set the duty cycle */
fan_set_duty(pwm_channels[ch].channel, percent);
}
int pwm_get_duty(enum pwm_channel ch)
{
int percent = fan_get_duty(pwm_channels[ch].channel);
if (pwm_channels[ch].flags & PWM_CONFIG_ACTIVE_LOW)
percent = 100 - percent;
return percent;
}
static void pwm_init(void)
{
int i;
for (i = 0; i < PWM_CH_COUNT; ++i)
fan_channel_setup(pwm_channels[i].channel,
(pwm_channels[i].flags &
PWM_CONFIG_HAS_RPM_MODE)
? FAN_USE_RPM_MODE : 0);
}
/* The chip-specific fan module initializes before this. */
DECLARE_HOOK(HOOK_INIT, pwm_init, HOOK_PRIO_INIT_PWM);