Character Device Driver note-platform device driver mechanism (1)

 

Platform device registration analysis:/* for the following resources, read the chip manual and view the schematic diagram */
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ARCH/ARM/plat-s3c24xx/Devs. c/* Most device controller resources are defined here */
/* LCD controller */
Static struct resource maid [] = {
[0] = {
. Start = s3c24xx_pa_ LCD,
. End = s3c24xx_pa_ LCD + s3c24xx_sz_ LCD-1,
. Flags = ioresource_mem,
},
[1] = {
. Start = irq_ LCD,
. End = irq_ LCD,
. Flags = ioresource_irq,
}
};

Static u64 maid = 0 xfffffffful;

Struct platform_device initi_device_ LCD = {
. Name = "s3c2410-lcd ",
. ID =-1,
. Num_resources = array_size (initi_ LCD _resource ),
. Resource = maid,
. Dev = {
. Dma_mask = & cloud_device_ LCD _dmamask,
. Coherent_dma_mask = 0 xfffffffful
}
};
/* The above just defines some resources. We need to register them to the linked list of platform devices */
ARCH/ARM/mach-s3c2410/mach-smdk2410.c
Static struct platform_device * smdk2410_devices [] _ initdata = {
& Initi_device_usb,
& Amp; cloud_device_ LCD,
& Amp; cloud_device_wdt,
& Amp; initi_device_i2c,
& Amp; cloud_device_iis,
& Amp; cloud_device_sdi
};
Static void _ init smdk2410_init (void)
{
S3c24xx_fb_set_platdata (& smdk2410_lcdcfg );
Platform_add_devices (smdk2410_devices, array_size (smdk2410_devices ));
......................
}
Platform_add_devices/* What does this function do */
Bytes -----------------------------------------------------------------------------------
For (I = 0; I <num; I ++ ){
Ret = platform_device_register (Devs [I]);

Platform_device_register/* this function is used to show how to load device resources to the device linked list */
Int platform_device_register (struct platform_device * pdev)
{
// Initialize device Properties
Device_initialize (& pdev-> Dev );
// Add the device to platfrom
Return platform_device_add (pdev );
}
Platform_device_add
Pdev-> Dev. Bus = & platform_bus_type;
...........
Ret = device_add (& pdev-> Dev);/* Start loading */
............../* Add device resources to the device linked list */
Bus_attach_device (Dev);/* find the driver to match */
Ret = device_attach (Dev );
/* Search for each driver in the drive list on the bus and call _ device_attach */
Ret = bus_for_each_drv (Dev-> bus, null, Dev, _ device_attach );

_ Device_attach:/* calls the same function as the driver. It calls the match function in the bus struct and matches the function by name */
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