硬件平台: am335x
内核版本: linux-3.8.13
编译器版本: arm-linux-gnueabi-gcc 4.7.3


添加spidev设备

1.在内核配置菜单中选中SPI驱动

Device Drivers  --->
     [*] SPI support  --->
        <*>   McSPI driver for OMAP
        <*>   User mode SPI device driver support
  1. 在设备树上添加spidev设备
    查看相关代码driver/spi/spidev.c,其值为"rohm,dh2228fv"

修改dts文件,添加以下代码

&spi1 {
    status = "okay";
    pinctrl-names = "default";
    pinctrl-0 = <&mcspi1_pins>;
    
    //创建SPI设备/dev/spidev1.0
    spidev@0 {
        status = "okay";
        compatible = "rohm,dh2228fv";    // 重要
        spi-max-frequency=<24000000>;
        reg = <0>;
    };
};

至此,可以在/dev/目录下看到spidev设备文件