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From:   Bhaumik Bhatt <bbhatt@codeaurora.org>
To:     manivannan.sadhasivam@linaro.org
Cc:     linux-arm-msm@vger.kernel.org, hemantk@codeaurora.org,
        jhugo@codeaurora.org, linux-kernel@vger.kernel.org,
        Bhaumik Bhatt <bbhatt@codeaurora.org>
Subject: [PATCH v3 1/7] bus: mhi: core: Abort suspends due to outgoing pending packets
Date:   Mon, 18 May 2020 13:03:55 -0700
Message-Id: <1589832241-13867-2-git-send-email-bbhatt@codeaurora.org>
In-Reply-To: <1589832241-13867-1-git-send-email-bbhatt@codeaurora.org>
References: <1589832241-13867-1-git-send-email-bbhatt@codeaurora.org>
Sender: linux-kernel-owner@vger.kernel.org
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Add the missing check to abort suspends if a client 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@codeaurora.org>
---
 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 7960980..661d704 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;
 	}
-- 
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