[PATCH v2 01/10] soundwire: intel: disable shim wake on suspend

[Bard Liao <yung-chuan.liao@linux.intel.com>]

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

If we enabled the clock stop mode and suspend, we need to disable the
shim wake. We do so only if the parent is pm_runtime active due to
power rail dependencies.

GitHub issue: https://github.com/thesofproject/linux/issues/1678
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
---
 drivers/soundwire/intel.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
index ebca8ced59ec..aa8484366c95 100644
--- a/drivers/soundwire/intel.c
+++ b/drivers/soundwire/intel.c
@@ -1532,6 +1532,7 @@ static int __maybe_unused intel_suspend(struct device *dev)
 	struct sdw_cdns *cdns = dev_get_drvdata(dev);
 	struct sdw_intel *sdw = cdns_to_intel(cdns);
 	struct sdw_bus *bus = &cdns->bus;
+	u32 clock_stop_quirks;
 	int ret;
 
 	if (bus->prop.hw_disabled) {
@@ -1543,6 +1544,23 @@ static int __maybe_unused intel_suspend(struct device *dev)
 	if (pm_runtime_suspended(dev)) {
 		dev_dbg(dev, "%s: pm_runtime status: suspended\n", __func__);
 
+		clock_stop_quirks = sdw->link_res->clock_stop_quirks;
+
+		if ((clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET ||
+		     !clock_stop_quirks) &&
+		    !pm_runtime_suspended(dev->parent)) {
+
+			/*
+			 * if we've enabled clock stop, and the parent
+			 * is still active, disable shim wake. The
+			 * SHIM registers are not accessible if the
+			 * parent is already pm_runtime suspended so
+			 * it's too late to change that configuration
+			 */
+
+			intel_shim_wake(sdw, false);
+		}
+
 		return 0;
 	}
 
-- 
2.17.1