> -----Original Message----- > From: Felipe Balbi [mailto:balbi@xxxxxx] > Sent: Wednesday, November 05, 2014 8:43 PM > To: Krzysztof Opasiak > Cc: balbi@xxxxxx; gregkh@xxxxxxxxxxxxxxxxxxx; > bigeasy@xxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; > s.wadas@xxxxxxxxxxx; k.lewandowsk@xxxxxxxxxxx; > andrzej.p@xxxxxxxxxxx; m.szyprowski@xxxxxxxxxxx > Subject: Re: [RFC PATCH] usb: gadget: composite: Provide list of > registered functions > > On Mon, Oct 20, 2014 at 01:41:37PM +0200, Krzysztof Opasiak wrote: > > Driver which provides implementation of some USB functions > registers > > its usb_function_driver structure in framework. > > Function drivers are identifed using registered name. > > > > When gadget is composed user must know what names has been > > "user *must" know", why ? Because he has to create directory with suitable name. This means that he needs to know that Mass storage module has been registered as mass_storage, and that gadget zero provides functions registered as Loopback and SourceSink. Let's say that you got system and kernel image. You may use uname -r to learn about kernel version, let's say that it is 3.17. You may also check what kernel modules has been provided with image. But how to learn which usb function has been build into kernel? I see some analogy to filesystems. When you would like to use -t option in mount you have to know how Ext4 or Function FS has been registered in fs framework. Kernel allows you to learn about all loaded or build-in modules. You may simply do this using /proc/filesystems where you will get all fs names registered in kernel. So in a few steps: 1. I have some disk image with Ext4. I would like to know if I have support for this fs type in my kernel and what name should I use to -t option. 2. I check my kernel modules but Ext4 not found 3. cat /proc/filesystems and I see that yes there is Ext4 and it has been compiled-in my kernel and it has been registered as "ext4" 4. Now I have gather all information and I may simply mount -t ext4 ... Don't you think that such scenario should be also doable with usb functions? User ends up in empty functions dir of some gadget and what now? How to allow him to ask kernel what is available? How to learn what functions has been build-in and what names has been registered in framework? (ocf kernel config but it's not always available) -- Krzysiek -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
