[PATCH v5 08/10] bus: mhi: core: Use counters to track MHI device state transitions

Bhaumik Bhatt
2020-07-23T22:37:33Z

Use counters to track MHI device state transitions such as those
to M0, M2, or M3 states. This helps in better debug by allowing
the user to see the number of transitions to a certain state when
queried using the states debugfs entry.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
---
drivers/bus/mhi/core/pm.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
index 27bb471..ce4d969 100644
--- a/drivers/bus/mhi/core/pm.c
+++ b/drivers/bus/mhi/core/pm.c
@@ -256,6 +256,7 @@ int mhi_pm_m0_transition(struct mhi_controller *mhi_cntrl)
dev_err(dev, "Unable to transition to M0 state\n");
return -EIO;
}
+ mhi_cntrl->M0++;

/* Wake up the device */
read_lock_bh(&mhi_cntrl->pm_lock);
@@ -326,6 +327,8 @@ void mhi_pm_m1_transition(struct mhi_controller *mhi_cntrl)
mhi_cntrl->dev_state = MHI_STATE_M2;

write_unlock_irq(&mhi_cntrl->pm_lock);
+
+ mhi_cntrl->M2++;
wake_up_all(&mhi_cntrl->state_event);

/* If there are any pending resources, exit M2 immediately */
@@ -362,6 +365,7 @@ int mhi_pm_m3_transition(struct mhi_controller *mhi_cntrl)
return -EIO;
}

+ mhi_cntrl->M3++;
wake_up_all(&mhi_cntrl->state_event);

return 0;