[PATCH 03/18] bus: mhi: core: Abort suspends due to outgoing pending packets

From: Manivannan Sadhasivam
Date: Mon Sep 21 2020 - 12:09:03 EST


From: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>

Add the missing check to abort suspends if a client driver has pending
outgoing packets to send to the device. This allows better utilization
of the MHI bus wherein clients on the host are not left waiting for
longer suspend or resume cycles to finish for data transfers.

Signed-off-by: Bhaumik Bhatt <bbhatt@xxxxxxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
drivers/bus/mhi/core/pm.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
index 796098078083..661d704c8093 100644
--- a/drivers/bus/mhi/core/pm.c
+++ b/drivers/bus/mhi/core/pm.c
@@ -686,7 +686,8 @@ int mhi_pm_suspend(struct mhi_controller *mhi_cntrl)
return -EIO;

/* Return busy if there are any pending resources */
- if (atomic_read(&mhi_cntrl->dev_wake))
+ if (atomic_read(&mhi_cntrl->dev_wake) ||
+ atomic_read(&mhi_cntrl->pending_pkts))
return -EBUSY;

/* Take MHI out of M2 state */
@@ -712,7 +713,8 @@ int mhi_pm_suspend(struct mhi_controller *mhi_cntrl)

write_lock_irq(&mhi_cntrl->pm_lock);

- if (atomic_read(&mhi_cntrl->dev_wake)) {
+ if (atomic_read(&mhi_cntrl->dev_wake) ||
+ atomic_read(&mhi_cntrl->pending_pkts)) {
write_unlock_irq(&mhi_cntrl->pm_lock);
return -EBUSY;
}
--
2.17.1