[PATCH v2 02/12] soundwire: intel: reset pm_runtime status during system resume

From: Bard Liao
Date: Mon Aug 17 2020 - 23:23:25 EST


From: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>

The system resume does the entire bus re-initialization and brings it
to full-power. If the device was pm_runtime suspended, there is no
need to run the pm_runtime resume sequence after the system runtime.

Follow the documentation from runtime_pm.rst, and conditionally
disable, set_active and re-enable the device on system resume.

Note that pm_runtime_suspended() is used instead of
pm_runtime_status_suspended() so that we can deal with the case where
pm_runtime is disabled.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Signed-off-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
---
drivers/soundwire/intel.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
index 85a0bb6af4fe..0e21bae3cd19 100644
--- a/drivers/soundwire/intel.c
+++ b/drivers/soundwire/intel.c
@@ -1434,6 +1434,12 @@ static int intel_suspend(struct device *dev)
return 0;
}

+ if (pm_runtime_suspended(dev)) {
+ dev_dbg(dev, "%s: pm_runtime status: suspended\n", __func__);
+
+ return 0;
+ }
+
ret = sdw_cdns_enable_interrupt(cdns, false);
if (ret < 0) {
dev_err(dev, "cannot disable interrupts on suspend\n");
@@ -1494,6 +1500,16 @@ static int intel_resume(struct device *dev)
return 0;
}

+ if (pm_runtime_suspended(dev)) {
+ dev_dbg(dev, "%s: pm_runtime status was suspended, forcing active\n", __func__);
+
+ /* follow required sequence from runtime_pm.rst */
+ pm_runtime_disable(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_enable(dev);
+ }
+
ret = intel_init(sdw);
if (ret) {
dev_err(dev, "%s failed: %d", __func__, ret);
--
2.17.1