bus: mhi: core: Trigger host resume if suspended during mhi_device_get()

It is possible that the host may be suspending or suspended and may
not allow an outgoing device wake assert immediately if a client has
requested for it. Ensure that the host wakes up and allows for it so
the client does not have to wait for an external trigger or an
outgoing packet to be queued for the host resume to occur.
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20200929175218.8178-6-manivannan.sadhasivam@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/bus/mhi/core/pm.c

@@ -1112,6 +1112,9 @@ void mhi_device_get(struct mhi_device *mhi_dev)
 
 	mhi_dev->dev_wake++;
 	read_lock_bh(&mhi_cntrl->pm_lock);
+	if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state))
+		mhi_trigger_resume(mhi_cntrl);
+
 	mhi_cntrl->wake_get(mhi_cntrl, true);
 	read_unlock_bh(&mhi_cntrl->pm_lock);
 }