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    <p>OK, so I appear to have fallen into answering my own question here, but I see that a number of people are getting confused over the apparent support for USB Host and the "odd" behaviours that can be observed so hopefully this answer may help some of you out.</p> <p>I posed 3 questions, I have a definitive answer for 1 &amp; 3 but I am less certain about the other at this stage.</p> <p>1) What exactly is missing, and why does this result in a bad claim? The problem is that the device, a <a href="http://www.amazon.co.uk/gp/product/B0011DYG1O/ref=oh_details_o00_s00_i00" rel="nofollow">lindy IRDA dongle</a> is being detected by the host (my Xperia Neo handset) but that the only configuration that it supports is demanding too much power for the handset to support. </p> <p>Oddly, this does not prevent either a) the device from being detected and enumerated by the Android libraries or b) from it appearing to be powered (red LED glowing)</p> <p>There is no report at the time of the failing claimInterface() call from any system libraries, however a dmesg|tail running when the device is attached gave the necessary insight.</p> <pre><code>dmesg | tail &lt;3&gt;usb 1-1: device v066f p4200 is not supported &lt;6&gt;usb 1-1: New USB device found, idVendor=066f, idProduct=4200 &lt;6&gt;usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=0 &lt;6&gt;usb 1-1: Product: IrDA/USB Bridge &lt;6&gt;usb 1-1: Manufacturer: Sigmatel Inc &lt;6&gt;usb 1-1: rejected 1 configuration due to insufficient available bus power &lt;4&gt;usb 1-1: no configuration chosen from 1 choice </code></pre> <p>Further investigation showed that this little device was claiming a requirement for 440mA which seems rather a lot but there seems little that can be done about it.</p> <p>Questions 2 Can anything that does not require root be done to work around this? It seems not. In theory I could provide external power to the device through the use of a USB Y cable or similar hackery but I don't believe that that would change the underlying problem that the handset refuses the demand. Even with root it is not clear that anything can be done to override the power profile. </p> <p>Question 3, is there a way to override the claimInterface() failure and force the communications? This is a blunt no. The device has simply not been created by the kernel so there is nothing there to override in the first place. Which does make it somewhat puzzling as to why the Android libraries still offer it up.</p>
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    1. POAndroid USBHost mode - why does my IRDA device fail on claimInterface?
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    1. POAndroid USBHost mode - why does my IRDA device fail on claimInterface?
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    1. COAnswering your own question is perfectly fine at SO, in fact it is encouraged! Nothing worse than a question with no answer...
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    2. COThanks Adam, I agree its frustrating to search and find the perfect match for a problem you have only to find that it has no answer. It would be good to know if after a month or 6 months the person who asked had not resolved the issue and had found some other workaround.
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    3. COMaybe it's worth looking at [Meta Stack Overflow](http://meta.stackoverflow.com/), perhaps such functionality has been proposed, or maybe you could propose it?
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