117 lines
3.1 KiB
C
117 lines
3.1 KiB
C
|
/**
|
||
|
|
* The MIT License (MIT)
|
||
|
|
*
|
||
|
|
* Copyright (c) 2016 sheinz (https://github.com/sheinz)
|
||
|
|
*
|
||
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
||
|
|
* of this software and associated documentation files (the "Software"), to deal
|
||
|
|
* in the Software without restriction, including without limitation the rights
|
||
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||
|
|
* copies of the Software, and to permit persons to whom the Software is
|
||
|
|
* furnished to do so, subject to the following conditions:
|
||
|
|
*
|
||
|
|
* The above copyright notice and this permission notice shall be included in
|
||
|
|
* all copies or substantial portions of the Software.
|
||
|
|
*
|
||
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||
|
|
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
||
|
|
* THE SOFTWARE.
|
||
|
|
*/
|
||
|
|
#ifndef __I2S_DMA_H__
|
||
|
|
#define __I2S_DMA_H__
|
||
|
|
|
||
|
|
#include <stdint.h>
|
||
|
|
#include <stdbool.h>
|
||
|
|
#include "esp/slc_regs.h"
|
||
|
|
|
||
|
|
typedef void (*i2s_dma_isr_t)(void);
|
||
|
|
|
||
|
|
typedef struct dma_descriptor {
|
||
|
|
uint32_t blocksize:12;
|
||
|
|
uint32_t datalen:12;
|
||
|
|
uint32_t unused:5;
|
||
|
|
uint32_t sub_sof:1;
|
||
|
|
uint32_t eof:1;
|
||
|
|
uint32_t owner:1;
|
||
|
|
|
||
|
|
void* buf_ptr;
|
||
|
|
struct dma_descriptor *next_link_ptr;
|
||
|
|
} dma_descriptor_t;
|
||
|
|
|
||
|
|
typedef struct {
|
||
|
|
uint8_t bclk_div;
|
||
|
|
uint8_t clkm_div;
|
||
|
|
} i2s_clock_div_t;
|
||
|
|
|
||
|
|
typedef struct {
|
||
|
|
bool data;
|
||
|
|
bool clock;
|
||
|
|
bool ws;
|
||
|
|
} i2s_pins_t;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Initialize I2S and DMA subsystems.
|
||
|
|
*
|
||
|
|
* @param isr ISR handler. Can be NULL if interrupt handling is not needed.
|
||
|
|
* @param clock_div I2S clock configuration.
|
||
|
|
* @param pins I2S pin configuration. Specifies which pins are enabled in I2S.
|
||
|
|
*/
|
||
|
|
void i2s_dma_init(i2s_dma_isr_t isr, i2s_clock_div_t clock_div, i2s_pins_t pins);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Calculate I2S dividers for the specified frequency.
|
||
|
|
*
|
||
|
|
* I2S_FREQ = 160000000 / (bclk_div * clkm_div)
|
||
|
|
* Base frequency is independent from the CPU frequency.
|
||
|
|
*/
|
||
|
|
i2s_clock_div_t i2s_get_clock_div(int32_t freq);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Start I2S transmittion.
|
||
|
|
*
|
||
|
|
* @param descr Pointer to the first descriptor in the linked list of descriptors.
|
||
|
|
*/
|
||
|
|
void i2s_dma_start(dma_descriptor_t *descr);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Stop I2S transmittion.
|
||
|
|
*/
|
||
|
|
void i2s_dma_stop();
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Clear interrupt in the I2S ISR handler.
|
||
|
|
*
|
||
|
|
* It is intended to be called from ISR.
|
||
|
|
*/
|
||
|
|
inline void i2s_dma_clear_interrupt()
|
||
|
|
{
|
||
|
|
SLC.INT_CLEAR = 0xFFFFFFFF;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Check if it is EOF interrupt.
|
||
|
|
*
|
||
|
|
* It is intended to be called from ISR.
|
||
|
|
*/
|
||
|
|
inline bool i2s_dma_is_eof_interrupt()
|
||
|
|
{
|
||
|
|
return (SLC.INT_STATUS & SLC_INT_STATUS_RX_EOF);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Get pointer to a descriptor that caused EOF interrupt.
|
||
|
|
* It is the last processed descriptor.
|
||
|
|
*
|
||
|
|
* It is intended to be called from ISR.
|
||
|
|
*/
|
||
|
|
inline dma_descriptor_t *i2s_dma_get_eof_descriptor()
|
||
|
|
{
|
||
|
|
return (dma_descriptor_t*)SLC.RX_EOF_DESCRIPTOR_ADDR;
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif // __I2S_DMA_H__
|