MCUME/MCUME_pico/FatFs_SPI/sd_driver/sd_spi.c

90 wiersze
2.7 KiB
C
Executable File

/* ========================================
*
* Copyright YOUR COMPANY, THE YEAR
* All Rights Reserved
* UNPUBLISHED, LICENSED SOFTWARE.
*
* CONFIDENTIAL AND PROPRIETARY INFORMATION
* WHICH IS THE PROPERTY OF your company.
*
* ========================================
*/
/* Standard includes. */
#include <stdint.h>
#include <stdio.h>
//
#include "my_debug.h"
#include "sd_card.h"
#include "sd_spi.h"
#include "spi.h"
//#define TRACE_PRINTF(fmt, args...)
#define TRACE_PRINTF printf // task_printf
void sd_spi_go_high_frequency(sd_card_t *this) {
uint actual = spi_set_baudrate(this->spi->hw_inst, this->spi->baud_rate);
TRACE_PRINTF("%s: Actual frequency: %lu\n", __FUNCTION__, (long)actual);
}
void sd_spi_go_low_frequency(sd_card_t *this) {
uint actual = spi_set_baudrate(this->spi->hw_inst, 100 * 1000);
TRACE_PRINTF("%s: Actual frequency: %lu\n", __FUNCTION__, (long)actual);
}
// Would do nothing if this->ss_gpio were set to GPIO_FUNC_SPI.
void sd_spi_select(sd_card_t *this) {
uint8_t fill = SPI_FILL_CHAR;
spi_write_blocking(this->spi->hw_inst, &fill, 1);
// asm volatile("nop \n nop \n nop"); // FIXME
gpio_put(this->ss_gpio, 0);
//asm volatile("nop \n nop \n nop"); // FIXME
spi_write_blocking(this->spi->hw_inst, &fill, 1);
LED_ON();
}
void sd_spi_deselect(sd_card_t *this) {
uint8_t fill = SPI_FILL_CHAR;
spi_write_blocking(this->spi->hw_inst, &fill, 1);
// asm volatile("nop \n nop \n nop"); // FIXME
gpio_put(this->ss_gpio, 1);
//asm volatile("nop \n nop \n nop"); // FIXME
LED_OFF();
/*
MMC/SDC enables/disables the DO output in synchronising to the SCLK. This
means there is a posibility of bus conflict with MMC/SDC and another SPI
slave that shares an SPI bus. Therefore to make MMC/SDC release the MISO
line, the master device needs to send a byte after the CS signal is
deasserted.
*/
spi_write_blocking(this->spi->hw_inst, &fill, 1);
}
void sd_spi_acquire(sd_card_t *this) {
sd_spi_select(this);
}
void sd_spi_release(sd_card_t *this) {
sd_spi_deselect(this);
}
uint8_t sd_spi_write(sd_card_t *this, const uint8_t value) {
// TRACE_PRINTF("%s\n", __FUNCTION__);
u_int8_t received = SPI_FILL_CHAR;
int num = spi_write_read_blocking(this->spi->hw_inst, &value, &received, 1);
myASSERT(1 == num);
return received;
}
bool sd_spi_transfer(sd_card_t *this, const uint8_t *tx, uint8_t *rx,
size_t length) {
return spi_transfer(this->spi, tx, rx, length);
}
void sd_spi_init_pl022(sd_card_t *this) {
// Let the PL022 SPI handle it.
// the CS line is brought high between each byte during transmission.
gpio_set_function(this->ss_gpio, GPIO_FUNC_SPI);
}
/* [] END OF FILE */