On Fri, Apr 15, 2011 at 4:09 AM, Greg KH <greg@xxxxxxxxx> wrote:
> On Thu, Apr 14, 2011 at 01:48:46PM +0800, yingchun li wrote:
>> Hi,
>> I have a mobile device, and using USB general serial driver to
>> put some log to PC.
>
> Ick, don't use that driver for any "real" work. What type of device is
> this really? We should use the real driver for it.
Why I cannot use this driver? does this driver have problems?
>> In user space, there is an APP reading from pipe and writing log data
>> to serial continually.
>> when I start the APP, then insert the usb cable, I can see the
>> log data sent to PC continually.
>> but if I remove the cable, and reconnect it again, the APP is block in
>> the write function, and
>> cannot send data to PC anymore.
>> following is main logic of APP,
>>
>> open pipe,
>> open usb serial(/dev/ttyGS0)
>>
>> for (;;) {
>> read from pipe
>> write to serial(with block mode)
>> if write error (that means receive serial disconnect signal, and
>> write I/O error)
>> close serial
>> open serial again
>> }
>>
>> so, could anyone give me some advice? your any feedback is appreciate.
>
> Are you using the tty interface properly? What happens when your
> application gets the hangup signal? Does it disconnect and reconnect to
> the new device that shows up when the device is plugged in?
>
> thanks,
>
> greg k-h
>
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
