[char-misc v4] mei: me: reduce the scope on unexpected reset

[Alexander Usyskin <alexander.usyskin@intel.com>]

After commit 2cedb296988c ("mei: me: trigger link reset if hw ready is unexpected")
some devices started to show long resume times (5-7 seconds).
This happens as mei falsely detects unready hardware,
starts parallel link reset flow and triggers link reset timeouts
in the resume callback.

Address it by performing detection of unready hardware only
when driver is in the MEI_DEV_ENABLED state instead of blacklisting
states as done in the original patch.
This eliminates active waitqueue check as in MEI_DEV_ENABLED state
there will be no active waitqueue.

Reviewed-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Reported-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221023
Tested-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Fixes: 2cedb296988c ("mei: me: trigger link reset if hw ready is unexpected")
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
---

V4: extend commit message, add Rafael's r-b

V3: reword commit message, add Rafael and PM list

V2: rebase over v7.0-rc4

 drivers/misc/mei/hw-me.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/drivers/misc/mei/hw-me.c b/drivers/misc/mei/hw-me.c
index d4612c659784..1e4a41ac428f 100644
--- a/drivers/misc/mei/hw-me.c
+++ b/drivers/misc/mei/hw-me.c
@@ -1337,19 +1337,13 @@ irqreturn_t mei_me_irq_thread_handler(int irq, void *dev_id)
 	/*  check if we need to start the dev */
 	if (!mei_host_is_ready(dev)) {
 		if (mei_hw_is_ready(dev)) {
-			/* synchronized by dev mutex */
-			if (waitqueue_active(&dev->wait_hw_ready)) {
-				dev_dbg(&dev->dev, "we need to start the dev.\n");
-				dev->recvd_hw_ready = true;
-				wake_up(&dev->wait_hw_ready);
-			} else if (dev->dev_state != MEI_DEV_UNINITIALIZED &&
-				   dev->dev_state != MEI_DEV_POWERING_DOWN &&
-				   dev->dev_state != MEI_DEV_POWER_DOWN) {
+			if (dev->dev_state == MEI_DEV_ENABLED) {
 				dev_dbg(&dev->dev, "Force link reset.\n");
 				schedule_work(&dev->reset_work);
 			} else {
-				dev_dbg(&dev->dev, "Ignore this interrupt in state = %d\n",
-					dev->dev_state);
+				dev_dbg(&dev->dev, "we need to start the dev.\n");
+				dev->recvd_hw_ready = true;
+				wake_up(&dev->wait_hw_ready);
 			}
 		} else {
 			dev_dbg(&dev->dev, "Spurious Interrupt\n");
-- 
2.43.0