[PATCH 5/5] bus: host: mhi: Need to honor sys_err at power_up state

From: Vivek . Pernamitta
Date: Thu Jul 03 2025 - 11:15:57 EST


From: Vivek Pernamitta <quic_vpernami@xxxxxxxxxxx>

In mhi_sync_power_up() host waits for device to enter in to mission mode
but SYS_ERR is an valid state, If device sends an SYS_ERR host will bail
out for wait_event_timeout() as MHI is in error state and calls
mhi_power_down which will teardown MHI driver probe.

If there is any SYS_ERR, sys_err handler needs to process SYS_ERR state
and queues the next state transition for device to bring in to Mission
mode, so mhi_sync_power_up() will wait for device to enter in to
mission mode.

Signed-off-by: Vivek Pernamitta <quic_vpernami@xxxxxxxxxxx>
---
drivers/bus/mhi/host/internal.h | 2 ++
drivers/bus/mhi/host/pm.c | 2 +-
2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/bus/mhi/host/internal.h b/drivers/bus/mhi/host/internal.h
index 1054e67bb450d2634771d092ed42bbdd63380472..00e46176654d8dc2f28b1535d9ef68233266ff3b 100644
--- a/drivers/bus/mhi/host/internal.h
+++ b/drivers/bus/mhi/host/internal.h
@@ -170,6 +170,8 @@ enum mhi_pm_state {
MHI_PM_IN_ERROR_STATE(pm_state))
#define MHI_PM_IN_SUSPEND_STATE(pm_state) (pm_state & \
(MHI_PM_M3_ENTER | MHI_PM_M3))
+#define MHI_PM_IN_BAD_STATE(pm_state) ((pm_state == MHI_PM_FW_DL_ERR) || \
+ (pm_state >= MHI_PM_SYS_ERR_FAIL))

#define NR_OF_CMD_RINGS 1
#define CMD_EL_PER_RING 128
diff --git a/drivers/bus/mhi/host/pm.c b/drivers/bus/mhi/host/pm.c
index 2af34980e14250cada75c981b690bc9581715212..ee50efc57cf713a7cf38a670cb49ab09a83b30ee 100644
--- a/drivers/bus/mhi/host/pm.c
+++ b/drivers/bus/mhi/host/pm.c
@@ -1280,7 +1280,7 @@ int mhi_sync_power_up(struct mhi_controller *mhi_cntrl)
mhi_cntrl->ready_timeout_ms : mhi_cntrl->timeout_ms;
wait_event_timeout(mhi_cntrl->state_event,
MHI_IN_MISSION_MODE(mhi_cntrl->ee) ||
- MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state),
+ MHI_PM_IN_BAD_STATE(mhi_cntrl->pm_state),
msecs_to_jiffies(timeout_ms));

ret = (MHI_IN_MISSION_MODE(mhi_cntrl->ee)) ? 0 : -ETIMEDOUT;

--
2.34.1