[PATCH v2 04/10] soundwire: intel: add missing support for all clock stop modes

From: Bard Liao
Date: Tue Sep 01 2020 - 23:00:02 EST


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

Deal with the BUS_RESET case, which is the default. The only change is
to add support for the exit sequence using the syncArm/syncGo mode for
the exit reset sequence.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Signed-off-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
---
drivers/soundwire/intel.c | 49 +++++++++++++++++++++++++++++++--------
1 file changed, 39 insertions(+), 10 deletions(-)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
index 259e3da98e42..8634d33c388c 100644
--- a/drivers/soundwire/intel.c
+++ b/drivers/soundwire/intel.c
@@ -1868,11 +1868,6 @@ static int intel_resume_runtime(struct device *dev)

if (!clock_stop0) {

- /*
- * Re-initialize the IP since it was powered-off
- */
- sdw_cdns_init(&sdw->cdns);
-
/*
* make sure all Slaves are tagged as UNATTACHED and
* provide reason for reinitialization
@@ -1880,13 +1875,31 @@ static int intel_resume_runtime(struct device *dev)

status = SDW_UNATTACH_REQUEST_MASTER_RESET;
sdw_clear_slave_status(bus, status);
- }

+ ret = sdw_cdns_enable_interrupt(cdns, true);
+ if (ret < 0) {
+ dev_err(dev, "cannot enable interrupts during resume\n");
+ return ret;
+ }

- ret = sdw_cdns_enable_interrupt(cdns, true);
- if (ret < 0) {
- dev_err(dev, "cannot enable interrupts during resume\n");
- return ret;
+ /*
+ * follow recommended programming flows to avoid
+ * timeouts when gsync is enabled
+ */
+ if (multi_link)
+ intel_shim_sync_arm(sdw);
+
+ /*
+ * Re-initialize the IP since it was powered-off
+ */
+ sdw_cdns_init(&sdw->cdns);
+
+ } else {
+ ret = sdw_cdns_enable_interrupt(cdns, true);
+ if (ret < 0) {
+ dev_err(dev, "cannot enable interrupts during resume\n");
+ return ret;
+ }
}

ret = sdw_cdns_clock_restart(cdns, !clock_stop0);
@@ -1894,6 +1907,22 @@ static int intel_resume_runtime(struct device *dev)
dev_err(dev, "unable to restart clock during resume\n");
return ret;
}
+
+ if (!clock_stop0) {
+ ret = sdw_cdns_exit_reset(cdns);
+ if (ret < 0) {
+ dev_err(dev, "unable to exit bus reset sequence during resume\n");
+ return ret;
+ }
+
+ if (multi_link) {
+ ret = intel_shim_sync_go(sdw);
+ if (ret < 0) {
+ dev_err(sdw->cdns.dev, "sync go failed during resume\n");
+ return ret;
+ }
+ }
+ }
} else if (!clock_stop_quirks) {
ret = intel_init(sdw);
if (ret) {
--
2.17.1