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From: Greg KH <gregkh@linuxfoundation.org>
To: Joakim Tjernlund <Joakim.Tjernlund@infinera.com>
Cc: "linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>
Subject: Re: ttyACM strange chars appearing at connect
Date: Tue, 19 May 2020 14:54:00 +0200	[thread overview]
Message-ID: <20200519125400.GA410029@kroah.com> (raw)
In-Reply-To: <52b8c126634058e3a455dc0ab8b0c542916db543.camel@infinera.com>

On Tue, May 19, 2020 at 12:14:55PM +0000, Joakim Tjernlund wrote:
> Whenever we connect a Linux laptop(4.19.118) to our ttyACM serial gadget we can see som strange
> chars appearing in our gadget:
> 03�`3�03�x�x(in hex: 3033 efbf bd60 33ef bfbd 3033 efbf bd78 efbf bd78)
> They appear witch c.a 1 sec in between.
> I assume it is the laptops ACM driver emitting those, but why? Can these chars be turned off?

It's a program on your laptop probing the device.  Usually modemmanager
or something like that.

greg k-h

  reply	other threads:[~2020-05-19 12:54 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-19 12:14 ttyACM strange chars appearing at connect Joakim Tjernlund
2020-05-19 12:54 ` Greg KH [this message]
2020-05-19 13:24   ` Joakim Tjernlund
2020-05-20 12:43   ` Joakim Tjernlund
2020-05-20 13:08     ` Dan Williams
2020-05-20 13:29       ` Joakim Tjernlund

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