[PATCH 3/4] drivers/misc: Add ASpeed LPC control driver

Greg KH gregkh at linuxfoundation.org
Fri Jan 13 04:27:13 AEDT 2017

On Thu, Jan 12, 2017 at 10:29:37AM -0600, Benjamin Herrenschmidt wrote:
> So I think the best approach here is:
> 	- A pair of ioctls to read and write random registers in the
> LPC bridge for all the "generally configuration gunk". These have a
> filter to ensure that the registers controlling the above mapping
> cannot be accessed that way.
> 	- An ioctl to control the above mapping window. It takes as
> arguments the location in LPC space, the window type (flash vs.
> memory), for memory, maybe an ID (several windows to chose from), and
> the offset& size in the latter. The driver can enforce that the windows
> are one of the specially reserved areas of memory etc...
> 	- An mmap function to map those reserved windows into userspace
> so the daemon can communicate appropriately (only needed for the memory
> windows, the flash space is accessed via the normal /dev/mtd drivers)
> Greg, does that make sense ?

Yes, that makes a lot more sense to me.  Thanks for writing it up,
hopefully it survives into the next driver submission, otherwise I'll
ask the same questions again due to not having a short-term memory at
all :)


greg k-h

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