On Mon, Nov 03, 2014 at 10:11:02AM -0600, Felipe Balbi wrote: > Hi, > > On Thu, Oct 09, 2014 at 03:21:51PM +0200, Robert Baldyga wrote: > > Since we can compose gadgets from many functions, there is the problem > > related to gadget breakage while FunctionFS daemon being closed. FFS > > function is userspace code so there is no way to know when it will close > > files (it doesn't matter what is the reason of this situation, it can > > be daemon logic, program breakage, process kill or any other). So when > > we have another function in gadget which, for example, sends some amount > > of data, does some software update or implements some real-time functionality, > > we may want to keep the gadget connected despite FFS function is no longer > > functional. > > > > We can't just remove one of functions from gadget since it has been > > enumerated, so the only way to keep entire gadget working is to make > > broken FFS function deactivated but still visible to host. For this > > purpose this patch introduces "no_disconnect" mode. It can be enabled > > by setting mount option "no_disconnect=1", and results with defering > > function disconnect to the moment of reopen ep0 file or filesystem > > unmount. After closing all endpoint files, FunctionFS is set to state > > FFS_DEACTIVATED. > > > > When ffs->state == FFS_DEACTIVATED: > > - function is still bound and visible to host, > > - setup requests are automatically stalled, > > - transfers on other endpoints are refused, > > - epfiles, except ep0, are deleted from the filesystem, > > - opening ep0 causes the function to be closes, and then FunctionFS > > is ready for descriptors and string write, > > - unmounting of the FunctionFS instance causes the function to be closed. > > > > Signed-off-by: Robert Baldyga <r.baldyga@xxxxxxxxxxx> > > David, you have been messing with ffs lately, can I get a Tested-by from > you on this patch ? ping. David ? Any chance you can test this one out ? -- balbi
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