spidev_test.c中的错误 spi 9bits 模式 messge构造

看注释吧，

/*
* SPI testing utility (using spidev driver)
*
* Copyright (c) 2007 MontaVista Software, Inc.
* Copyright (c) 2007 Anton Vorontsov <avorontsov@ru.mvista.com>
*
* 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.
*
* Cross-compile with cross-gcc -I/path/to/cross-kernel/include
*/

#include <stdint.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <getopt.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/types.h>
#include "spidev.h"

#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))

static void pabort(const char *s)
{
perror(s);
abort();
}

static const char *device = "/dev/spidev0.0";
static uint8_t mode;
static uint8_t bits = 8;
static uint32_t speed = 500000;
static uint16_t delay;

static void transfer_test(int fd)
{
int ret;
uint8_t tx[] = {
0xAE,0x00,0x10,0x40,0x81,
0xdb,0xA1,0xA6,0xA8,0x63,
0xC8,0xD3,0x00,0xD5,0x80,
0xDA,0x12,0x8D,0x10,0xDB,
0x20,0xAF,
};
uint8_t rx[ARRAY_SIZE(tx)] = {0, };
struct spi_ioc_transfer tr = {
.tx_buf = (unsigned long)tx,
.rx_buf = (unsigned long)rx,
.len = sizeof(tx),//源码此处用ARRAY_SIZE计算是错误的。因为spi驱动要求此处的len为发送buffer的大小，即字节个数！
.delay_usecs = delay,
.speed_hz = speed,
.bits_per_word = bits,
};

ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
if (ret < 1)
pabort("can't send spi message");

for (ret = 0; ret < ARRAY_SIZE(tx); ret++) {
if (!(ret % 6))
puts("");
printf("%.2X ", rx[ret]);
}
puts("");
}

/*发送位宽为9bit的数据，因为spi控制器支持的位宽一般为4~16位，spi驱动要求对于位宽大于8的数据，在发送buffer中采用2字节存储每个数据。
驱动在这种情况下的buffer指针(next++)每次将会后移2字节。而对于小于等于8位位宽的发送模式，数据在发送buffer中采用单字节存储，发送时
buffer指针每次后移1字节。
以下函数中的数据将采用9bit模式发送。因此对于发送message的构造和上面的函数不一样。请仔细对比。
举例：
static void send_cmd(int fd, uint8_t *data_buf)
{
int ret;
uint16_t tx[100] = {0};
uint16_t rx[ARRAY_SIZE(tx)] = {0};
int i = 0;

for(i=0;i<100;i++)
{//重新构造发送数据，在每个数据的最高位添加一个1，就变成了一个9bit的数据，放在一个uint16_t类型(2字节)中。
tx[i] = 0x100 | (uint16_t)data_buf[i];
}

struct spi_ioc_transfer tr = {
.tx_buf = (unsigned long)tx,
.rx_buf = (unsigned long)rx,
.len = sizeof(tx),//此处len的值为200
.delay_usecs = delay,
.speed_hz = speed,
.bits_per_word = bits,
};

ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
if (ret < 1)
pabort("can't send spi message");

}
*/

static void send_cmd(int fd, uint8_t cmd)
{
int ret;
uint16_t tx[1] = {0};
uint16_t rx[ARRAY_SIZE(tx)] = {0};

tx[0] = cmd;

struct spi_ioc_transfer tr = {
.tx_buf = (unsigned long)tx,
.rx_buf = (unsigned long)rx,
.len = sizeof(tx),
.delay_usecs = delay,
.speed_hz = speed,
.bits_per_word = bits,
};

ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
if (ret < 1)
pabort("can't send spi message");

}

static void send_data(int fd, uint8_t data)
{
int ret;
uint16_t tx[1];
uint16_t rx[ARRAY_SIZE(tx)] = {0};

tx[0] = 0x100 | (uint16_t)data;

struct spi_ioc_transfer tr = {
.tx_buf = (unsigned long)tx,
.rx_buf = (unsigned long)rx,
.len = sizeof(tx),
.delay_usecs = delay,
.speed_hz = speed,
.bits_per_word = bits,
};

ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
if (ret < 1)
pabort("can't send spi message");

}

static void print_usage(const char *prog)
{
printf("Usage: %s [-DsbdlHOLC3]\n", prog);
puts(" -D --device device to use (default /dev/spidev1.1)\n"
" -s --speed max speed (Hz)\n"
" -d --delay delay (usec)\n"
" -b --bpw bits per word \n"
" -l --loop loopback\n"
" -H --cpha clock phase\n"
" -O --cpol clock polarity\n"
" -L --lsb least significant bit first\n"
" -C --cs-high chip select active high\n"
" -3 --3wire SI/SO signals shared\n");
exit(1);
}

static void parse_opts(int argc, char *argv[])
{
while (1) {
static const struct option lopts[] = {
{ "device", 1, 0, 'D' },
{ "speed", 1, 0, 's' },
{ "delay", 1, 0, 'd' },
{ "bpw", 1, 0, 'b' },
{ "loop", 0, 0, 'l' },
{ "cpha", 0, 0, 'H' },
{ "cpol", 0, 0, 'O' },
{ "lsb", 0, 0, 'L' },
{ "cs-high", 0, 0, 'C' },
{ "3wire", 0, 0, '3' },
{ "no-cs", 0, 0, 'N' },
{ "ready", 0, 0, 'R' },
{ NULL, 0, 0, 0 },
};
int c;

c = getopt_long(argc, argv, "D:s:d:b:lHOLC3NR", lopts, NULL);

if (c == -1)
break;

switch (c) {
case 'D':
device = optarg;
break;
case 's':
speed = atoi(optarg);
break;
case 'd':
delay = atoi(optarg);
break;
case 'b':
bits = atoi(optarg);
break;
case 'l':
mode |= SPI_LOOP;
break;
case 'H':
mode |= SPI_CPHA;
break;
case 'O':
mode |= SPI_CPOL;
break;
case 'L':
mode |= SPI_LSB_FIRST;
break;
case 'C':
mode |= SPI_CS_HIGH;
break;
case '3':
mode |= SPI_3WIRE;
break;
case 'N':
mode |= SPI_NO_CS;
break;
case 'R':
mode |= SPI_READY;
break;
default:
print_usage(argv[0]);
break;
}
}
}

/******************************************************
//初始化IC函数
******************************************************/
void Init_IC(int fd)
{
send_cmd(fd, 0xAE); //Set Display Off
send_cmd(fd, 0xd5); //display divide ratio/osc. freq. mode
send_cmd(fd, 0x80); //
send_cmd(fd, 0xA8); //multiplex ration mode:63
send_cmd(fd, 0x3F);
send_cmd(fd, 0xD3); //Set Display Offset
send_cmd(fd, 0x00);
send_cmd(fd, 0x40); //Set Display Start Line
send_cmd(fd, 0xAD); //DC-DC Control Mode Set
send_cmd(fd, 0x8B); //DC-DC ON/OFF Mode Set
send_cmd(fd, 0x32); //Set Pump voltage value
send_cmd(fd, 0xA1); //Segment Remap
send_cmd(fd, 0xC8); //Sst COM Output Scan Direction
send_cmd(fd, 0xDA); //common pads hardware: alternative
send_cmd(fd, 0x12);
send_cmd(fd, 0x81); //contrast control
send_cmd(fd, 0xff);
send_cmd(fd, 0xD9); //set pre-charge period
send_cmd(fd, 0x22);
send_cmd(fd, 0xDB); //VCOM deselect level mode
send_cmd(fd, 0x18); //
send_cmd(fd, 0xA4); //Set Entire Display On/Off
send_cmd(fd, 0xA6); //Set Normal Display
send_cmd(fd, 0xAF); //Set Display On
}

#define STATE_MAX 0xFF
#define STATE_MIN 0x00
#define STATE_55 0x55
#define STATE_AA 0xAA
#define START_PAGE 0xB0
#define PAGE_TOTAL 8
#define START_HIGH_BIT 0x10
#define START_LOW_BIT 0x02
#define FRAME_HIGH_ROW 0x01
#define FRAME_LOW_ROW 0x80

#define MIN 0
#define COLUMN_MAX 128
#define ROW_MAX 64
//
//
#define Slave_Address 0x7B // 器件地址
#define OP_Command 0x00
#define OP_Data 0x40
//
//
#define Manual 1
#define Auto 0

/******************************************************
//全屏显示模式
******************************************************/
void All_Screen(int fd)
{
uint8_t page_number,column_number;
for(page_number=MIN;page_number<PAGE_TOTAL;page_number++)
{
send_cmd(fd, START_PAGE+page_number);
send_cmd(fd, START_HIGH_BIT);
send_cmd(fd, START_LOW_BIT);
for(column_number=MIN;column_number<COLUMN_MAX;column_number++)
{
send_data(fd, STATE_MAX);
}
}
}

int main(int argc, char *argv[])
{
int ret = 0;
int fd;

parse_opts(argc, argv);

fd = open(device, O_RDWR);
if (fd < 0)
pabort("can't open device");

/*
* spi mode
*/
// ret = ioctl(fd, SPI_IOC_WR_MODE, &mode);
// if (ret == -1)
// pabort("can't set spi mode");

ret = ioctl(fd, SPI_IOC_RD_MODE, &mode);
if (ret == -1)
pabort("can't get spi mode");

/*
* bits per word
*/
ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);
if (ret == -1)
pabort("can't set bits per word");

ret = ioctl(fd, SPI_IOC_RD_BITS_PER_WORD, &bits);
if (ret == -1)
pabort("can't get bits per word");

/*
* max speed hz
*/
// ret = ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed);
// if (ret == -1)
// pabort("can't set max speed hz");

ret = ioctl(fd, SPI_IOC_RD_MAX_SPEED_HZ, &speed);
if (ret == -1)
pabort("can't get max speed hz");

printf("Do Not set mode!!!\n");
printf("spi device: %s\n", device);
printf("spi mode: %d\n", mode);
printf("bits per word: %d\n", bits);
printf("max speed: %d Hz (%d KHz)\n", speed, speed/1000);

//transfer_test(fd);

printf("start transfer\n");
Init_IC(fd);
All_Screen(fd);

close(fd);
return ret;
}