spin_lock_irqsave(&bitbang->lock, flags);
}
bitbang->busy = 0;
/* [cgw]: 退出临界区 */
spin_unlock_irqrestore(&bitbang->lock, flags);
}

代码：

spi_platform_dev.c

#include

static struct spi_board_info board_info[1] = {
{
.modalias = "spi_ssd1306", /* [cgw]: spi设备名，和设备驱动名对应 */
.bus_num = 0, /* [cgw]: spi总线号，即spi0 */
.chip_select = 2, /* [cgw]: spi总线上的设备号,即spi0.2 */
.max_speed_hz = 50000, /* [cgw]: spi时钟 */
.mode = SPI_MODE_3, /* [cgw]: spi数据模式 */
},
};

static void ssd1306_chip_select(struct s3c2410_spigpio_info *spi, int cs)
{
/* [cgw]: 选中设备号为2的spi设备 */
if (spi->board_info->chip_select == 2) {
s3c2410_gpio_cfgpin(S3C2410_GPG2, S3C2410_GPIO_OUTPUT);
/* [cgw]: 选中设备 */
if (BITBANG_CS_ACTIVE == cs) {
s3c2410_gpio_setpin(S3C2410_GPG2, 0);
/* [cgw]: 释放设备 */
} else if (BITBANG_CS_INACTIVE == cs) {
s3c2410_gpio_setpin(S3C2410_GPG2, 1);
}
}
}

/* [cgw]: */
static struct s3c2410_spigpio_info spi_dev = {
.pin_clk = S3C2410_GPG7,
.pin_mosi = S3C2410_GPG5,
.pin_miso = S3C2410_GPG6,
.board_size = 1, /* [cgw]: 设置板上spi接口数量为1 */
.board_info = &board_info[0],
.chip_select = ssd1306_chip_select
};

static void spi_dev_release(struct device * dev)
{
printk("spi_dev_release! \n");
}

/* [cgw]: 分配一个平台设备 */
static struct platform_device spi_platform_dev = {
.name = "s3c24xx-spi-gpio", /* [cgw]: 设置平台设备名，和平台驱动名对应 */
.id = -1,
.dev = {
.release = spi_dev_release,
.platform_data = (void *)&spi_dev, /* [cgw]: 通过platform_data传递spi_dev给平台驱动
* 平台驱动可以访问spi_dev
*/
},
};

static int spi_dev_init(void)
{
/* [cgw]: 注册spi_platform_dev平台设备 */
platform_device_register(&spi_platform_dev);
return 0;
}

static void spi_dev_exit(void)
{
/* [cgw]: 注销spi_platform_dev平台设备 */
platform_device_unregister(&spi_platform_dev);
}

module_init(spi_dev_init);
module_exit(spi_dev_exit);

MODULE_LICENSE("GPL");

spi_ssd1306_drv.c

#include
#include
#include
#include
#include
#include
#include
#include

#define SSD1306_CMD 0
#define SSD1306_DAT 1

#define SSD1306_WIDTH 128
#define SSD1306_HEIGHT 64

static uint8_t s_chDispalyBuffer[128][8];