Messages in this thread | | | Date | Mon, 26 Apr 2010 22:14:54 +0200 | From | Josua Dietze <> | Subject | Re: USB gadget with drivers "on board" |
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Alan Stern schrieb:
> On Mon, 26 Apr 2010, Josua Dietze wrote: >> These are the notorious mode switching devices. In Windows, they >> obviously install a special storage driver doing one specific action >> on each following plugging. >> This action - some storage or control command - will "flip" the >> device, making it "disconnect" and returning as a completely different >> composite device. >> >> Storage commands used for this procedure range from "SCSI rezero" over >> "passthrough" to "SCSI eject", or involve vendor specific stuff. > > I was going to say the same thing. For ease of use, I recommend using > a "SCSI eject" to trigger the mode change. That way, Linux users who > don't have the usb-modeswitch program installed can get the same effect > by running eject.
Important for the Linux handling is that "mode 1" is clearly distinguishable from "mode 2", either by using a different product ID or by setting a different class for the device or interface 0 (will most likely be "8" for the install mode).
And it might be a good idea not to re-use any known ID for the install mode, like the 05c6:1000 which my Samsung phone and loads of other devices are using. This makes switch handling complicated (though not impossible).
Josua Dietze
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