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I've been able to stop the disconnecting loop. <br>
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First I tried the <code>usbcore.autosuspend=-1</code> guessing that an inactive period of time will send the device to some low power state, explaining the enumerating and disconnect loop with, but I had no luck.</div>
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Then I force using the device with an udev rule running <br>
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evtest --query $DEVNAME EV_KEY 0</div>
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and the disconnection disappears. Maybe it's an error in the tobis touchscreen controller code??<br>
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I would like to test if the behavior changes in full speed instead of high speed. Is there some way to downgrade the EHCI speed to full speed?</div>
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Thanks!<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>De:</b> Greg KH <gregkh@linuxfoundation.org><br>
<b>Enviado:</b> martes, 20 de abril de 2021 10:52<br>
<b>Para:</b> Jorge Fernandez Monteagudo <jorgefm@cirsa.com><br>
<b>Cc:</b> kernelnewbies@kernelnewbies.org <kernelnewbies@kernelnewbies.org><br>
<b>Asunto:</b> Re: USB resets</font>
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<div class="PlainText">On Tue, Apr 20, 2021 at 07:41:14AM +0000, Jorge Fernandez Monteagudo wrote:<br>
> >Bad hardware, the kernel can not cause a disconnect :(<br>
> ><br>
> >Do you have a flaky cable or underpowerd hub here?<br>
> ><br>
> <br>
> How many retries before the kernel decides to send a reset to a USB device? After a reset, this device is ignored?<br>
<br>
The hub itself disconnects the device electronically, the kernel does<br>
not do that. When the device comes back, then it is initialized by the<br>
kernel, as the logs show, but then it is disconnected again.<br>
<br>
This really looks like broken hardware or electronic noise on the<br>
connection, the kernel can not cause electronic disconnects on a USB hub<br>
like this.<br>
<br>
good luck!<br>
<br>
greg k-h<br>
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