This is a note to let you know that I've just added the patch titled
bus: mhi: host: Skip MHI reset if device is in RDDM
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bus-mhi-host-skip-mhi-reset-if-device-is-in-rddm.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From cabce92dd805945a090dc6fc73b001bb35ed083a Mon Sep 17 00:00:00 2001
From: Qiang Yu <quic_qianyu@xxxxxxxxxxx>
Date: Thu, 18 May 2023 14:22:39 +0800
Subject: bus: mhi: host: Skip MHI reset if device is in RDDM
From: Qiang Yu <quic_qianyu@xxxxxxxxxxx>
commit cabce92dd805945a090dc6fc73b001bb35ed083a upstream.
In RDDM EE, device can not process MHI reset issued by host. In case of MHI
power off, host is issuing MHI reset and polls for it to get cleared until
it times out. Since this timeout can not be avoided in case of RDDM, skip
the MHI reset in this scenarios.
Cc: <stable@xxxxxxxxxxxxxxx>
Fixes: a6e2e3522f29 ("bus: mhi: core: Add support for PM state transitions")
Signed-off-by: Qiang Yu <quic_qianyu@xxxxxxxxxxx>
Reviewed-by: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <mani@xxxxxxxxxx>
Link: https://lore.kernel.org/r/1684390959-17836-1-git-send-email-quic_qianyu@xxxxxxxxxxx
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/bus/mhi/host/pm.c | 5 +++++
1 file changed, 5 insertions(+)
--- a/drivers/bus/mhi/host/pm.c
+++ b/drivers/bus/mhi/host/pm.c
@@ -466,6 +466,10 @@ static void mhi_pm_disable_transition(st
/* Trigger MHI RESET so that the device will not access host memory */
if (!MHI_PM_IN_FATAL_STATE(mhi_cntrl->pm_state)) {
+ /* Skip MHI RESET if in RDDM state */
+ if (mhi_cntrl->rddm_image && mhi_get_exec_env(mhi_cntrl) == MHI_EE_RDDM)
+ goto skip_mhi_reset;
+
dev_dbg(dev, "Triggering MHI Reset in device\n");
mhi_set_mhi_state(mhi_cntrl, MHI_STATE_RESET);
@@ -483,6 +487,7 @@ static void mhi_pm_disable_transition(st
mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0);
}
+skip_mhi_reset:
dev_dbg(dev,
"Waiting for all pending event ring processing to complete\n");
mhi_event = mhi_cntrl->mhi_event;
Patches currently in stable-queue which might be from quic_qianyu@xxxxxxxxxxx are
queue-5.15/bus-mhi-host-skip-mhi-reset-if-device-is-in-rddm.patch
