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标题: The probe function in s3c2410fb.c(kernel 2.6.16) [打印本页]

作者: grep_one 时间: 2006-04-12 09:40
标题: The probe function in s3c2410fb.c(kernel 2.6.16)
在s3c2410fb.c中，在平台相关的设备探测函数中有这么一段code，请高手帮忙看看。

static int __init s3c2410fb_probe(struct platform_device *pdev)
{
……
static struct s3c2410fb_mach_info *mach_info;
……
mach_info = pdev->dev.platform_data;
if (mach_info == NULL)
{
      dev_err(&pdev->dev,"no platform data for lcd, cannot attach\n");
      return -EINVAL;
}
mregs = &mach_info->regs;
   ……
}

mach_info,platform_data和platform_device的声明如下：

struct s3c2410fb_mach_info {
unsigned char fixed_syncs; /* do not update sync/border */

/* Screen size */
int width;
int height;

/* Screen info */
struct s3c2410fb_val xres;
struct s3c2410fb_val yres;
struct s3c2410fb_val bpp;

/* lcd configuration registers */
struct s3c2410fb_hw  regs;

/* GPIOs */

unsigned long gpcup;
unsigned long gpcup_mask;
unsigned long gpccon;
unsigned long gpccon_mask;
unsigned long gpdup;
unsigned long gpdup_mask;
unsigned long gpdcon;
unsigned long gpdcon_mask;

/* lpc3600 control register */
unsigned long lpcsel;
};

struct device {
struct klist klist_children;
struct klist_node knode_parent; /* node in sibling list */
struct klist_node knode_driver;
struct klist_node knode_bus;
struct device * parent;

struct kobject kobj;
char bus_id[BUS_ID_SIZE]; /* position on parent bus */
struct device_attribute uevent_attr;

struct semaphore sem; /* semaphore to synchronize calls to
   * its driver.
   */

struct bus_type * bus; /* type of bus device is on */
struct device_driver *driver; /* which driver has allocated this
   device */
void *driver_data; /* data private to the driver */

            void *platform_data; /* Platform specific data, device
   core doesn't touch it */
void *firmware_data; /* Firmware specific data (e.g. ACPI,
   BIOS data),reserved for device core*/
struct dev_pm_info power;

u64 *dma_mask; /* dma mask (if dma'able device) */
u64 coherent_dma_mask;/* Like dma_mask, but for
      alloc_coherent mappings as
      not all hardware supports
      64 bit addresses for consistent
      allocations such descriptors. */

struct list_head dma_pools; /* dma pools (if dma'ble) */

struct dma_coherent_mem *dma_mem; /* internal for coherent mem
      override */

void (*release)(struct device * dev);
};

struct platform_device {
const char * name;
u32 id;
struct device dev;
u32 num_resources;
struct resource * resource;
};

请问上面那段代码怎么理解？代码的细节可以参看内核源代码。fb核心是怎样用这么个void *得到设备信息的？

[ 本帖最后由 grep_one 于 2006-4-12 09:54 编辑 ]

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