esp-idf/components/esp_hw_support/clk_ctrl_os.c

57 wiersze
1.7 KiB
C

// Copyright 2020 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include <freertos/FreeRTOS.h>
#include "soc/clk_ctrl_os.h"
#define DELAY_RTC_CLK_SWITCH 5
static portMUX_TYPE periph_spinlock = portMUX_INITIALIZER_UNLOCKED;
static uint8_t s_periph_ref_counts = 0;
static uint32_t s_rtc_clk_freq = 0; // Frequency of the 8M/256 clock in Hz
bool periph_rtc_dig_clk8m_enable(void)
{
portENTER_CRITICAL(&periph_spinlock);
if (s_periph_ref_counts == 0) {
rtc_dig_clk8m_enable();
s_rtc_clk_freq = rtc_clk_freq_cal(rtc_clk_cal(RTC_CAL_8MD256, 100));
if (s_rtc_clk_freq == 0) {
portEXIT_CRITICAL(&periph_spinlock);
return false;
}
}
s_periph_ref_counts++;
portEXIT_CRITICAL(&periph_spinlock);
return true;
}
uint32_t periph_rtc_dig_clk8m_get_freq(void)
{
return s_rtc_clk_freq * 256;
}
void periph_rtc_dig_clk8m_disable(void)
{
portENTER_CRITICAL(&periph_spinlock);
assert(s_periph_ref_counts > 0);
s_periph_ref_counts--;
if (s_periph_ref_counts == 0) {
s_rtc_clk_freq = 0;
rtc_dig_clk8m_disable();
}
portEXIT_CRITICAL(&periph_spinlock);
}