g_file_storage写大文件问题的解决

先前一直被g_file_storage写大文件时比较慢的问题困扰，终于在网上找到了解决方法。现整理如下：

 1.修改arch/arm/plat-s3c24xx/common-smdk.c

/*USB device上拉电阻处理 */

static void smdk2410_udc_pullup(enum s3c2410_udc_cmd_e cmd)

{

   u8 *s3c2410_pullup_info[] = {

        " ",

        "Pull-up enable",

        "Pull-up disable",

        "UDC reset, in case of"

   };

  printk("smdk2410_udc: %s\n",s3c2410_pullup_info[cmd]);   s3c2410_gpio_cfgpin(S3C2410_GPG（9）, S3C2410_GPIO_OUTPUT);

switch (cmd)

{

case S3C2410_UDC_P_ENABLE :

s3c2410_gpio_setpin(S3C2410_GPG（9）, 1); //set gpg9 output HIGH break; case S3C2410_UDC_P_DISABLE :

s3c2410_gpio_setpin(S3C2410_GPG（9）, 0); //set gpg9 output LOW break; case S3C2410_UDC_P_RESET :

//FIXME!!!

 break;

 default:

 break;

 }

}

static struct s3c2410_udc_mach_info smdk2410_udc_cfg __initdata = {

.udc_command = smdk2410_udc_pullup,

};

static struct platform_device *smdk2410_devices[] __initdata = {

…,

&s3c_device_usbgadget, /*USB gadget device设备登记*/

};

 在void __init smdk_machine_init(void)函数中添加

s3c24xx_udc_set_platdata(&smdk2410_udc_cfg); /* 初始化*/

2.修改drivers/usb/gadget/file_storage.c

在static int fsg_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)函数中

- fsg->ep0req->zero = rc < w_length;

+ fsg->ep0req->zero = rc < w_length \

&& (rc % gadget->ep0->maxpacket) == 0;

3.修改drivers/usb/gadget/s3c2410_udc.c

 在static void s3c2410_udc_handle_ep(struct s3c2410_ep *ep)函数中

 struct s3c2410_request *req;

 int is_in = ep->bEndpointAddress & USB_DIR_IN;

 u32 ep_csr1;

 u32 idx;

 + handle_ep_again:

 ……

if ((ep_csr1 & S3C2410_UDC_OCSR1_PKTRDY) && req) {

s3c2410_udc_read_fifo(ep,req);

+ if (s3c2410_udc_fifo_count_out())

+   goto handle_ep_again;

}

4.修改内核配置

 <*> USB Gadget Support --->

  USB Peripheral Controller (S3C2410 USB Device Controller) -->       S3C2410 USB Device Controller

 [] S3C2410 udc debug messages

USB Gadget Drivers

File-backed Storage Gadget

5.编译及加载

 #make zImage

 #make modules

 # insmod g_file_storage.ko file=/dev/mmcblk0p1 stall=0 removable=1

经过在2.6.32.5内核上的测试拷贝5MB大小的文件很快完成