usbserial on ARM

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I have an ARM based board with usb interface.
To use the usb interface I use the following commands:
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If I try to use the device with echo or cat I get the error "No such
device".
Could you help me?

Bye


Re: usbserial on ARM
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vendor=0x... product=0x...
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"modprobe", which should load all dependencies as well. Eg: usbserial
probably needs the USB core, USB Hub, OHCI/EHCI .... modules etc.
Also check the log files  (dmesg, syslog etc) to see if those modules
were successfully loaded.
Cheers
  Janaka


Re: usbserial on ARM
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vendor=0x... product=0x...
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With modinfo I see that the module usbserial doesn't have dependency.
In this case insmod and modprobe do the same work?

modinfo drivers/usb/serial/usbserial.ko
filename:       drivers/usb/serial/usbserial.ko
author:         Greg Kroah-Hartman, snipped-for-privacy@kroah.com, http://www.kroah.com/linux /
description:    USB Serial Driver core
license:        GPL
vermagic:       2.6.18-rc2-rev.1.0.2.1 mod_unload ARMv5 gcc-3.3
depends:
parm:           product:User specified USB idProduct (ushort)
parm:           vendor:User specified USB idVendor (ushort)
parm:           debug:Debug enabled or not (bool)

Bye


Re: usbserial on ARM
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usbserial.ko vendor=0x... product=0x...
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That doesn't sound right!  You may have the core Usb modules ..etc
compiled in to the kernel or a strange setup.
The reason I say the above is, USB is a reasonably complex bus with
multiple levels of control.  At the highest level there must be a root
hub.  Some boards have a dedicated chip for this, and some others have
it on their processor (an SOC design). To enable and operate that you
need a kernel driver/module.
Next level down you may (or may not) have a USB hub, which increases
the number of USB devices that can be connected to the Root hub and
takes care of power needs.  This may have further control/driver
modules.
Next level down in the tree structure will be your device driver for
the USB serial product (Most likely a CDC [communications device] or a
HID [ Human interface Device]).
There may be more layers depending on the complexity of the HW setup.

The other thing could be that modinfo may not show all the
dependencies if a SOC controlling code is in a one big driver.
If none of the above helps, you can try dividing the problem and to
solve it:
1. Is the USB port working for other types of devices
2. Is the USB to serial setup working
Good luck!


Re: usbserial on ARM
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vendor=0x... product=0x...
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You do not have the device driver at all. usbserial is a
module for the common parts of USB serial drivers.

As an example, I plugged in a simple USB serial cable,
Aten International Co Ltd UC-232A, vendor ID 0x557 and
product ID 0x2008.

It needs the modules:

   pl2303
   usbserial, used by pl2303

The command

   modprobe pl2303

loads both modules.

HTH

--

Tauno Voipio
tauno voipio (at) iki fi


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