linux-kernel - [PATCH 2/3] soundwire: intel: disable WAKEEN in pm

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Date:   Wed, 20 Apr 2022 10:32:40 +0800
From:   Bard Liao <yung-chuan.liao@...ux.intel.com>
To:     alsa-devel@...a-project.org, vkoul@...nel.org
Cc:     vinod.koul@...aro.org, linux-kernel@...r.kernel.org,
        gregkh@...uxfoundation.org, srinivas.kandagatla@...aro.org,
        pierre-louis.bossart@...ux.intel.com, sanyog.r.kale@...el.com,
        bard.liao@...el.com
Subject: [PATCH 2/3] soundwire: intel: disable WAKEEN in pm_runtime resume

From: Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>

When the manager device is pm_runtime resumed, we see a series of
spurious wakes and attempts to resume the same device:

soundwire_intel.link.0: intel_resume_runtime: start
soundwire_intel.link.0: intel_link_power_up: powering up all links
soundwire_intel.link.0: intel_link_power_up: first link up, programming SYNCPRD
soundwire_intel.link.0: intel_shim_wake: WAKEEN disabled for link 0
soundwire_intel.link.0: intel_link_process_wakeen_event: pm_request_resume start
soundwire_intel.link.0: intel_link_process_wakeen_event: pm_request_resume done
soundwire_intel.link.0: intel_shim_wake: WAKEEN disabled for link 0
soundwire_intel.link.0: intel_link_process_wakeen_event: pm_request_resume start
soundwire_intel.link.0: intel_link_process_wakeen_event: pm_request_resume done

This sequence does not break anything but is totally unnecessary.

Currently the wakes are only disabled after the peripheral generates a
wake, e.g. for jack detection.

If the resume is initiated by the host drivers as a result of
userspace actions (play/record typically), we need to disable wake
detection as well. Doing so prevents the spurious wakes and calls to
pm_request_resume().

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@...ux.intel.com>
Reviewed-by: Rander Wang <rander.wang@...el.com>
Signed-off-by: Bard Liao <yung-chuan.liao@...ux.intel.com>
---
 drivers/soundwire/intel.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
index 32e5fdb823c4..4b458e5e7336 100644
--- a/drivers/soundwire/intel.c
+++ b/drivers/soundwire/intel.c
@@ -1831,6 +1831,9 @@ static int __maybe_unused intel_resume_runtime(struct device *dev)
 		return 0;
 	}
 
+	/* unconditionally disable WAKEEN interrupt */
+	intel_shim_wake(sdw, false);
+
 	link_flags = md_flags >> (bus->link_id * 8);
 	multi_link = !(link_flags & SDW_INTEL_MASTER_DISABLE_MULTI_LINK);
 
-- 
2.17.1