imx6 生成 spi设备节点

开发板需要使用spi接口，但是spi接口被touch占用，使用event进行操作。所以需要更改配置，生成spi设备节点。

参考链接

　　https://community.nxp.com/thread/322097

　　http://blog.****.net/yaolanshu_june/article/details/52152790

更改内核配置

make menuconfig

添加spi的支持，如下所示。

Device Drivers
    [*] SPI support  --->
            --- SPI support
                   *** SPI Master Controller Drivers ***
             < >   Altera SPI Controller
             -*-   Utilities for Bitbanging SPI masters
             < >   GPIO-based bitbanging SPI Master
             <*>   Freescale i.MX SPI controllers
             < >   OpenCores tiny SPI
             < >   ARM AMBA PL022 SSP controller
             < >   Xilinx SPI controller common module
             < >   DesignWare SPI controller core support
                   *** SPI Protocol Masters ***
             <*>   User mode SPI device driver support
             < >   Infineon TLE62X0 (for power switching)

添加spi设备

　　添加spi设备，名称一定要是'spidev'.

　　vi arch/arm/mach-mx6/board-mx6q_sabresd.c

static struct spi_board_info imx6_sabresd_spi_nor_device[] __initdata = {
    {
        .modalias = "spidev",
        .max_speed_hz = 50000, /* max spi clock (SCK) speed in HZ */
        .bus_num = 1,
        .chip_select = 0,
        .mode = SPI_MODE_1,
    },
};

从新编译内核，查看spi设备节点。

root@freescale ~$ ll /dev/spidev1.0
crw-rw----    1 root     root      153,   0 Jan  1 00:00 /dev/spidev1.0

Tony Liu

2016-10-20, Shenzhen