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标题: 读写SPI FLASH--驱动部分（7） [打印本页]

作者: yuyang911220 时间: 2015-2-27 09:09 标题: 读写SPI FLASH--驱动部分（7）

/*****************************************************************************
  Description:
Entry point for the driver.

  Parameters:
none

  Returns:
   0 => success
< 0 => error
******************************************************************************/
int spi_init(void)
{
int ret;
dev_t devno;
struct pci_dev *pdev = NULL;

spi_char.mem_base = 0;
spi_char.mem_ready = 0;

//request and reserve a device number
/* ret = alloc_chrdev_region(&spi_char.dev, 0, 1, DRIVERNAME);

if ( ret < 0)
{
      SPI_ERR("%s:spi_init-Could not register module/n", DRIVERNAME);
      return ret;
} */

//init cdev struct for adding device to kernel
cdev_init(&spi_char.cdev, &file_ops);
spi_char.cdev.owner = THIS_MODULE;
spi_char.cdev.ops = &file_ops;
spi_char.mem_size = SPI_FLASH_SIZE;

//devno = MKDEV(MAJOR(spi_char.dev), 0);
devno = MKDEV(MAJOR_NO, MINOR_NO);
SPI_DBG("major id:%d, minor id:%d/n", MAJOR(devno), MINOR(devno));
if(cdev_add(&spi_char.cdev, devno, 1))
{
      SPI_ERR("%s:spi_init-cdev_add failed/n", DRIVERNAME);
      goto Exit_Error;
}

//Get dev struct for the LPC device. The GPIO BAR is located in the
//LPC device config space
pdev = pci_get_device(SPI_VENDOR_ID, SPI_DEVICE_ID, NULL);
if ( !pdev )
{
      SPI_ERR("%s:spi_char_init-Could not find pci device/n", DRIVERNAME);
      goto Exit_Error;
}

//Get base address from the LPC configuration space.
pci_read_config_dword(pdev, CRBA_BAR, &(spi_char.mem_base));
SPI_DBG("base addr1 %08x/n", spi_char.mem_base);
//Get BIOS Contrl address
pci_read_config_byte(pdev, BIOS_CTRL, &(spi_char.bios_ctrl_addr));
SPI_DBG("bios ctrl addr %08x/n", spi_char.bios_ctrl_addr);

/* Get own base address */
spi_char.mem_base &= 0xFFFFC000;
SPI_DBG("base addr11 %08x/n", spi_char.mem_base);
spi_char.mem_base += SPI_BAR_OFFSET;
SPI_DBG("base addr21 %08x/n", spi_char.mem_base);

//release reference to device
pci_dev_put(pdev);

//obtain memory space
if ( !request_mem_region(spi_char.mem_base, SPI_MEM_SIZE, DRIVERNAME) )
{
      spi_char.iomem_ready = 0;
      SPI_ERR("%s:spi_init-IO memory region has been reserved?/n", DRIVERNAME);
}
else
{
      spi_char.iomem_ready = 1;
}
spi_char.mem_virt = ioremap(spi_char.mem_base, SPI_MEM_SIZE);
SPI_DBG("virtual addr %08x/n", spi_char.mem_virt);
//indicate memory space reserved
spi_char.mem_ready = 1;

//do some special initiation
EP80579_spi_init(spi_char.mem_virt);

goto Exit;

Exit_Error:
SPI_ERR("%s:spi_init-Initialization failed/n", DRIVERNAME);
spi_cleanup();
return -ENODEV;

Exit:
SPI_DBG("%s:spi_init-Initialization complete/n", DRIVERNAME);
return 0;
}

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