Question

我需要从头开始为omap4编写spi驱动程序。我指的是http://lxr.free-electrons.com/source/drivers/spi/spi-omap2-mcspi.c驱动程序代码。但是，我无法理解在此驱动程序代码中如何处理基本设备操作。例如，char驱动程序具有结构

struct file_operations scull_fops = {
.owner = THIS_MODULE,
.llseek = scull_llseek,
.read = scull_read,
.write = scull_write,
.ioctl = scull_ioctl,
.open = scull_open,
.release = scull_release,
};

包含指向基本函数的指针，如open，read，write等...

我找不到这些功能 http://lxr.free-electrons.com/source/drivers/spi/spi-omap2-mcspi.c

有人请帮我确定设备如何打开，阅读和放大write在spi-omap2-mcspi.c代码中提供。

Answer 1

如果查看帖子中链接的文件的底部，您将看到基本平台驱动程序操作的处理。

static const struct dev_pm_ops omap2_mcspi_pm_ops = {
        .resume = omap2_mcspi_resume,
        .runtime_resume = omap_mcspi_runtime_resume,
};

static struct platform_driver omap2_mcspi_driver = {
       .driver = {
                .name =         "omap2_mcspi",
                .owner =        THIS_MODULE,
                .pm =           &omap2_mcspi_pm_ops,
                .of_match_table = omap_mcspi_of_match,
       },
       .probe =        omap2_mcspi_probe,
       .remove =       omap2_mcspi_remove,
};

在probe操作中，您可以看到为此驱动程序设置spi特定操作：

     /* the spi->mode bits understood by this driver: */
     master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
     master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
     master->setup = omap2_mcspi_setup;
     master->auto_runtime_pm = true;
     master->transfer_one_message = omap2_mcspi_transfer_one_message;
     master->cleanup = omap2_mcspi_cleanup;
     master->dev.of_node = node;

spi驱动程序中的基本设备操作

1 个答案: