omap: remoteproc: return -EAGAIN on a suspend time out

Support has been added on the remote processor side to allow
applications to deny the remote processor from going into a
suspend state. If one or more applications on the remote
processor request to avoid suspend, then the suspend flag is
never set by the remote processor while the request is active,
resulting in a timeout on the host side suspend code.

The runtime suspend function for remoteproc returns -EIO at
present in case of a timeout, causing the runtime pm framework
to avoid further runtime pm suspend callbacks. This is not
desired and hence the return value is changed to -EAGAIN. This
allows the runtime pm framework to retry the suspend after the
re-expiration of the timeout. This would allow the applications
on the remote processor to allow or disallow suspend independently
of the host-side.

The inital idea of having -EIO was to avoid callbacks, since a
timeout would mean that the remoteproc is in an error state.
However, if the remoteproc were in a bad state at this point, the
recovery mechanism would kick in and reload the image.

Change-Id: Ic7b9cfa220724e8024b960704598ec93854de86c
Signed-off-by: Subramaniam C.A <subramaniam.ca@ti.com>
Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Miguel Vadillo <vadillo@ti.com>
Signed-off-by: Paul Hunt <hunt@ti.com>
omap: iommu: program constraints based on platform data
IOMMU driver requests and releases constraints in iommu_get
and iommu_put respectively. These constraints are actually
needed only on OMAP4 and beyond for sub-systems that have
an AMMU. The current driver code has these values hard-coded
for all the chips.

A new platform data field has been added now for the constraints
values, and this allows the values to be programmed based on
the OMAP chip and also allow a unique value if needed for each
iommu instance.

The logic in IOMMU driver code is adjusted to request the
constraints only if the relevant platform data field is set.