Re: USB Serial Converter driver and multiple devices

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]


On Tue, May 15, 2012 at 11:24 AM, Greg KH <greg@xxxxxxxxx> wrote:
> On Mon, May 14, 2012 at 11:31:51PM -0400, Russell Nelson wrote:
>> On Mon, May 14, 2012 at 6:56 PM, Greg KH <greg@xxxxxxxxx> wrote:
>>
>> > Again the usb-serial generic device is a very dumb, slow device, with no
>> > line settings at all.  It's ment for testing and one-off prototypes, not
>> > for "real" devices in any way.
>>
>> Okay, I am *seriously* confused, then, because I've seen instructions
>> on the 'net that used to work which tell me to modprobe usbserial with
>> a vendor and product number. Is "usb-serial not a functioning driver"
>> new information that I missed?
>
> Yes, and all of that is wrong and written by people who have no idea
> what they are doing.

Oh dear. I'm wondering why that wasn't obvious to me. Should it have
been? Maybe Bjørn has a good idea?

>> Maybe when it creates its entry in
>> /sys/bus/usb-serial/drivers/generic/ it should say "testing" instead
>> of "generic", because "generic" implies to me that it's going to work
>> with just about anything. You know, like generic drugs.
>
> True, but it's too late now, and it's not like changing that will make
> anyone realize the problem.

Isn't "generic" just an internal name? If it's misleading, maybe it
would be *better* to break it.

So .... since my device is an FTDI, I tried modprobe ftdi_sio
product=0xcc60 and that worked a champ.
I then tried echo 0x0403 0xcc60
>/sys/bus/usb-serial/drivers/ftdi_sio/new_id and *that* worked also.
It seems that it only doesn't work on the usbserial driver, as
described here: http://www.spinics.net/lists/linux-usb/msg46670.html
Sounds like there's some interaction between usbserial's policy of
only supporting one vendor/product pair and new_id, which causes the
latter to not work at all.

It looks like a Google search for "modprobe usbserial vendor" is
useful in finding the miscreant advice. In particular, this page:
http://wiki.debian.org/usbserial looks like a farrago of wrongness.
--
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


B and H Foto and Electronics Corp.

[Linux Media]     [Video for Linux]     [Linux Input]     [Linux Audio Users]     [Photo]     [Yosemite News]    [Yosemite Photos]    [Free Online Dating]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]     [More Archives]

Add to Google Powered by Linux