[PATCH v1 0/4] Updates to MHI channel handling

From: Bhaumik Bhatt
Date: Mon Nov 09 2020 - 17:44:19 EST


MHI specification shows a state machine with support for STOP channel command
and the validity of certain state transitions. MHI host currently does not
provide any mechanism to stop a channel and restart it without resetting it.
There are also times when the device moves on to a different execution
environment while client drivers on the host are unaware of it and still
attempt to reset the channels facing unnecessary timeouts.

This series addresses the above areas to provide support for stopping an MHI
channel, resuming it back, and improving upon channel state machine handling in
general.

This set of patches was tested on arm64 architecture.

Bhaumik Bhatt (4):
bus: mhi: core: Allow receiving a STOP channel command response
bus: mhi: core: Improvements to the channel handling state machine
bus: mhi: core: Add support to pause or resume channel data transfers
bus: mhi: core: Check execution environment for channel before issuing
reset

drivers/bus/mhi/core/init.c | 11 +-
drivers/bus/mhi/core/internal.h | 12 +++
drivers/bus/mhi/core/main.c | 218 ++++++++++++++++++++++++++++------------
include/linux/mhi.h | 16 +++
4 files changed, 192 insertions(+), 65 deletions(-)

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