On Mon, Mar 29, 2021 at 07:11:40PM -0700, Bhaumik Bhatt wrote:
> 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, improved documentation and improving upon channel
> state machine handling in general.
>
> This set of patches was tested on arm64 and x86_64 architecture.
>
Please rebase this series on top of mhi-next as some of the patches
doesn't apply cleanly.
Thanks,
Mani
> v7:
> -Tested on x86_64 architecture
> -Drop the patch "Do not clear channel context more than once" as issue is
> fixed
> differently using "bus: mhi: core: Fix double dma free()"
> -Update the commit text to better reflect changes on state machine
> improvements
>
> v6:
> -Dropped the patch which introduced start/stop transfer APIs for lack of users
> -Updated error handling and debug prints on channel handling improvements
> patch
> -Improved commit text to better explain certain patches based on review
> comments
> -Removed references to new APIs from the documentation improvement patch
>
> v5:
> -Added reviewed-by tags from Hemant I missed earlier
> -Added patch to prevent kernel warnings on clearing channel context twice
>
> v4:
> -Updated commit text/descriptions and addressed checkpatch checks
> -Added context validity check before starting/stopping channels from new API
> -Added patch to clear channel context configuration after reset/unprepare
>
> v3:
> -Updated documentation for channel transfer APIs to highlight differences
> -Create separate patch for "allowing channel to be disabled from stopped
> state"
>
> v2:
> -Renamed the newly introduced APIs to mhi_start_transfer() /
> mhi_stop_transfer()
> -Added improved documentation to avoid confusion with the new APIs
> -Removed the __ prefix from mhi_unprepare_channel() API for consistency.
>
> Bhaumik Bhatt (7):
> bus: mhi: core: Allow sending the STOP channel command
> bus: mhi: core: Clear context for stopped channels from remove()
> bus: mhi: core: Improvements to the channel handling state machine
> bus: mhi: core: Clear configuration from channel context during reset
> bus: mhi: core: Check channel execution environment before issuing
> reset
> bus: mhi: core: Remove __ prefix for MHI channel unprepare function
> bus: mhi: Improve documentation on channel transfer setup APIs
>
> drivers/bus/mhi/core/init.c | 22 -
> drivers/bus/mhi/core/internal.h | 12 +++
> drivers/bus/mhi/core/main.c | 192
>
> include/linux/mhi.h | 18 +++-
> 4 files changed, 163 insertions(+), 81 deletions(-)
>
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>
