[PATCH v2 08/12] bus: mhi: core: Move to an error state on mission mode failure

From: Bhaumik Bhatt
Date: Thu Oct 29 2020 - 21:53:31 EST


If the host receives a mission mode event and by the time it can get
to processing it, the register accesses fail implying a connectivity
error, MHI should move to an error state. This helps avoid longer wait
times from a synchronous power up perspective and accurately reflects
the MHI execution environment and power management states.

Signed-off-by: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
drivers/bus/mhi/core/pm.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
index 0299196..06adea2 100644
--- a/drivers/bus/mhi/core/pm.c
+++ b/drivers/bus/mhi/core/pm.c
@@ -383,10 +383,14 @@ static int mhi_pm_mission_mode_transition(struct mhi_controller *mhi_cntrl)
write_lock_irq(&mhi_cntrl->pm_lock);
if (MHI_REG_ACCESS_VALID(mhi_cntrl->pm_state))
mhi_cntrl->ee = mhi_get_exec_env(mhi_cntrl);
- write_unlock_irq(&mhi_cntrl->pm_lock);

- if (!MHI_IN_MISSION_MODE(mhi_cntrl->ee))
+ if (!MHI_IN_MISSION_MODE(mhi_cntrl->ee)) {
+ mhi_cntrl->pm_state = MHI_PM_LD_ERR_FATAL_DETECT;
+ write_unlock_irq(&mhi_cntrl->pm_lock);
+ wake_up_all(&mhi_cntrl->state_event);
return -EIO;
+ }
+ write_unlock_irq(&mhi_cntrl->pm_lock);

wake_up_all(&mhi_cntrl->state_event);

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