嵌入式Linux SPI驱动
1. Linux下SPI驱动框架
1.1 SPI主机驱动
作者：IOT技术栈
Linux使用spi_master结构体表示spi主机驱动，定义在 drivers/linux/spi/spi.h
transfer : 数据传输函数
transfer_one_message: SPI发送护具函数，发送一个spi_message数据
Linux内核使用spi_driver结构体表示spi设备驱动， 定义在 include/linux/spi/spi.h
struct spi_driver {
const struct spi_device_id *id_table;
int (*probe)(struct spi_device *spi);
int (*remove)(struct spi_device *spi);
void (*shutdown)(struct spi_device *spi);
struct device_driver driver;
};
1.3 SPI设备和驱动匹配过程
SPI设备和驱动的匹配过程是由SPI总线完成的，SPI总线为spi_bus_type，定义在 drivers/spi/spi.c
struct bus_type spi_bus_type = {
.name = "spi",
.dev_groups = spi_dev_groups,
.match = spi_match_device,
.uevent = spi_uevent,
};
spi设备和驱动的匹配函数是spi_match_device ，函数定义如下：
static int spi_match_device(struct device *dev, struct device_driver *drv)
{
const struct spi_device *spi = to_spi_device(dev);
const struct spi_driver *sdrv = to_spi_driver(drv);
/* Attempt an OF style match */
if (of_driver_match_device(dev, drv))
return 1;
/* Then try ACPI */
if (acpi_driver_match_device(dev, drv))
return 1;
if (sdrv->id_table)
return !!spi_match_id(sdrv->id_table, spi);
return strcmp(spi->modalias, drv->name) == 0;
}
2. I.MX6U SPI 主机驱动分析
作者：IOT技术栈
相关文章
Adeline
2020-07-08
Fidelia
2020-12-19
Jamina
2020-08-27
Meta
2023-07-22
Samira
2023-07-22
Ursula
2023-07-22
Radinka
2023-07-22
Gella
2023-07-22
Miette
2023-07-22
Zandra
2023-07-22
Kara
2023-07-22
Irma
2023-07-22
Kande
2023-08-08
Tricia
2023-08-08
Karli
2023-08-08
Ula
2023-08-08
Dulcea
2023-08-08
Malina
2023-08-08
Fawn
2023-08-08