Re: [PATCH v8] usb:serial:pl2303: add GPIOs interface on PL2303

From: Benjamin Henrion
Date: Thu Sep 04 2014 - 17:57:37 EST

On Thu, Sep 4, 2014 at 7:35 PM, Wang YanQing <udknight@xxxxxxxxx> wrote:
> On Sun, Aug 31, 2014 at 11:24:56PM +0800, Wang YanQing wrote:
>> PL2303 USB Serial devices may has GPIOs, this patch add
>> basic PL2303 gpio support.
>> Known issue:
>> If gpios are in use(export to userspace through sysfs interface, etc),
>> then call pl2303_release(unplug usb-serial convertor, modprobe -r, etc),
>> will cause trouble, so we need to make sure there is no gpio user before
>> call pl2303_release.
>> Signed-off-by: Wang YanQing <udknight@xxxxxxxxx>
>> ---
>> Note: I sniffed office HXD gpio test program to get
>> gpios control protocol with PL2303 RA, so I only
>> test it with PL2303 RA and HXA, I don't have HXD,
>> but because it is *office* HXD gpio test program,
>> so if it doesn't work with HXD, I will feel surprise.

I can confirm your patch is working fine on the HXD:

I am still hunting for a simple C program to test the speed of the
GPIOs and sysfs, if you have a good reference.


Benjamin Henrion <bhenrion at>
FFII Brussels - +32-484-566109 - +32-2-4148403
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