Re: [tpmdd-devel] [PATCH RFC 0/4] RFC: in-kernel resource manager

[Jason Gunthorpe]

On Wed, Jan 11, 2017 at 11:00:43AM +0100, Andreas Fuchs wrote:

> could we please get an ioctl, that switches the "mode" of the fd entirely.
> I'd like to see the write()/read() support still intact.
> All my current code uses main-loop based poll on the fd and I don't want
> to be force to start using threads...

We currently do not support poll in the kernel for /dev/tpmX.

ie we do not supply a poll method for 'struct file_operations'.

Even worse, the current implementation blocks returning from write()
until the TPM has completed its work, so it doesn't even make sense to
combine it with poll.

Jason