参考了手册和网上的文章。做下记录。

内核版本：linux-3.10

1. Add VID and PID

在/drivers/usb/serial/option.c添加:

static const struct usb_device_id option_ids[] = { #if 1 //Added by Quectel { USB_DEVICE(0x05C6, 0x9090) }, /* Quectel UC15 */ { USB_DEVICE(0x05C6, 0x9003) }, /* Quectel UC20 */ { USB_DEVICE(0x05C6, 0x9215) }, /* Quectel EC20 */ { USB_DEVICE(0x2C7C, 0x0125) }, /* Quectel EC25/EC20 R2.0 */ { USB_DEVICE(0x2C7C, 0x0121) }, /* Quectel EC21 */ #endif

然后在/drivers/usb/serial/qcserial.c 和/drivers/usb/serial/qcserial.c两个文件中注释掉如下语句

{USB_DEVICE(0x05c6, 0x9215)}, /* Acer Gobi 2000 Modem device (VP413) */

网上说是由于历史的原因，导致VID和PID重复了。

2. Add the Zero Packet Mechanism  

static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port, int endpoint, int dir, void *ctx, char *buf, int len, void (*callback) (struct urb *)) { struct usb_serial *serial = port->serial; struct urb *urb; urb = usb_alloc_urb(0, GFP_KERNEL); /* No ISO */ if (urb == NULL) { dev_dbg(&serial->interface->dev, "%s: alloc for endpoint %d failed.\n", __func__, endpoint); return NULL; } /* Fill URB using supplied data. */ usb_fill_bulk_urb(urb, serial->dev, usb_sndbulkpipe(serial->dev, endpoint) | dir, buf, len, callback, ctx); //ADD bye sky for zero packet if (dir == USB_DIR_OUT) { struct usb_device_descriptor *desc = &serial->dev->descriptor; if (desc->idVendor == cpu_to_le16(0x05C6) && desc->idProduct == cpu_to_le16(0x9090)) urb->transfer_flags |= URB_ZERO_PACKET; if (desc->idVendor == cpu_to_le16(0x05C6) && desc->idProduct == cpu_to_le16(0x9003)) urb->transfer_flags |= URB_ZERO_PACKET; if (desc->idVendor == cpu_to_le16(0x05C6) && desc->idProduct == cpu_to_le16(0x9215)) urb->transfer_flags |= URB_ZERO_PACKET; if (desc->idVendor == cpu_to_le16(0x2C7C)) urb->transfer_flags |= URB_ZERO_PACKET; } //=== return urb; }

3. Add Reset Resume

File: [KERNEL]/drivers/usb/serial/option.c

static struct usb_serial_driver option_1port_device = { …… #ifdef CONFIG_PM .suspend = usb_wwan_suspend, .resume = usb_wwan_resume, #if 1 //Added by Quectel .reset_resume = usb_wwan_resume, #endif #endif };

4. Use GobiNet or QMI WWAN

File: [KERNEL]/drivers/usb/serial/option.c  

static int option_probe(struct usb_serial *serial, const struct usb_device_id *id) { struct usb_wwan_intf_private *data; …… #if 1 //Added by Quectel //Quectel UC20's interface 4 can be used as USB Network device if (serial->dev->descriptor.idVendor == cpu_to_le16(0x05C6) && serial->dev->descriptor.idProduct == cpu_to_le16(0x9003) && serial->interface->cur_altsetting->desc.bInterfaceNumber >= 4) return -ENODEV; //Quectel EC20's interface 4 can be used as USB Network device if (serial->dev->descriptor.idVendor == cpu_to_le16(0x05C6) && serial->dev->descriptor.idProduct == cpu_to_le16(0x9215) && serial->interface->cur_altsetting->desc.bInterfaceNumber >= 4) return -ENODEV; //Quectel EC21&EC25&EC20 R2.0's interface 4 can be used as USB Network device if (serial->dev->descriptor.idVendor == cpu_to_le16(0x2C7C) && serial->interface->cur_altsetting->desc.bInterfaceNumber >= 4) return -ENODEV; #endif /* Store device id so we can use it during attach. */ usb_set_serial_data(serial, (void *)id); return 0; }

5.Enable CONFIG_USB_SERIAL_OPTION

重新烧写内核，然后将模块连接到USB HOST上。 重新上电稍等一下就可以检测到模块了。

在dev下发现： 

用AT命令测试下：

cat /dev/ttyUSB2 & echo "AT\r\n" >/dev/ttyUSB2

如果可以看到有数据返回，那就表明驱动已将OK了。硬件连接也没有问题了。。

 

6. GobiNet Driver for UC20/EC20/EC21/EC25/EC20 R2.0

下一步就是：GobiNet Driver for UC20/EC20/EC21/EC25/EC20 R2.0

类似这样的效果，会创建一个eht1的网卡设备。

将一些代码文件拷贝到“[KERNEL]/drivers/net/usb/目录下，代码来自官网，或者网上找找。

修改目录下的[KERNEL]/drivers/net/usb/Makefile文件 加入：

然后重新编译内核，并烧写内核。

上电后加载的驱动信息：

然后输入ifconfig -a查看

7 . Test GobiNet

编译quectel-CM

make CROSS-COMPILE=arm-linux-