MTK SPI设备驱动分析

一.MTK测试的SPI驱动

Spi-dev.c (kernel-3.18\drivers\spi\mediatek\mt6735)

 

struct spi_device_id spi_id_table = { "spi-ut", 0 };

static struct spi_driver spi_test_driver = {

.driver = {

.name = "test_spi",

.bus = &spi_bus_type,

.owner = THIS_MODULE,

},

.probe = spi_test_probe,

.remove = spi_test_remove,

.id_table = &spi_id_table,

};

 

static struct spi_board_info spi_board_devs[] __initdata = {

[0] = {

.modalias = "spi-ut",

.bus_num = 0,

.chip_select = 1,

.mode = SPI_MODE_3,

},

};

 

spi_dev_init

    spi_register_board_info(spi_board_devs, ARRAY_SIZE(spi_board_devs)); //注册spi设备的信息

        list_add_tail(&bi->list, &board_list);

list_for_each_entry(master, &spi_master_list, list)

spi_match_master_to_boardinfo(master, &bi->board_info); //如果有SPI控制器就NEW一个设备，见MTK SPI控制器驱动分析章节

    spi_register_driver(&spi_test_driver); //注册spi设备驱动

        sdrv->driver.bus = &spi_bus_type;

        driver_register(&sdrv->driver);

 

 

spi_driver的device_driver中的name字段肯定为"spi-ut".只有这样才能在SPI核心层的spi_match_device函数中匹配.

 

 

static DEVICE_ATTR(spi, 0200, NULL, spi_store);

static DEVICE_ATTR(spi_msg, 0200, NULL, spi_msg_store);

 

static struct device_attribute *spi_attribute[] = {

&dev_attr_spi,

&dev_attr_spi_msg,

};

 

spi_test_probe

   spi->mode = SPI_MODE_3;

    spi->bits_per_word = 32;

    return spi_create_attribute(&spi->dev);

        device_create_file(dev, spi_attribute[idx]);

            spi_msg

            spi_msg_store