ASoC: Intel: Skylake: Add support for deferred DSP module bind

Module at the end of DSP pipeline that needs to be connected to a module
in another pipeline are represented as a PGA(leaf node) and in PGA event
handler these modules are bound/unbounded. Modules other than PGA leaf
can be connected directly or via switch to a module in another pipeline.
Example: reference path.

To support the deferred DSP module bind, following changes are done:
o When the path is enabled, the destination module that needs to be
bound may not be initialized. If the module is not initialized, add
these modules in a deferred bind list.
o When the destination module is initialized, check for these modules
in deferred bind list. If found, bind them.
o When the destination module is deleted, Unbind the modules.
o When the source module is deleted, remove the entry from the deferred
bind list.

Signed-off-by: Jeeja KP <jeeja.kp@intel.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 12 insertions, 0 deletions

diff --git a/sound/soc/intel/skylake/skl-pcm.c b/sound/soc/intel/skylake/skl-pcm.c
index 1823197c15c8..600faad19bd4 100644
--- a/sound/soc/intel/skylake/skl-pcm.c
+++ b/sound/soc/intel/skylake/skl-pcm.c
@@ -1300,6 +1300,7 @@ int skl_platform_register(struct device *dev)
 	struct skl *skl = ebus_to_skl(ebus);
 
 	INIT_LIST_HEAD(&skl->ppl_list);
+	INIT_LIST_HEAD(&skl->bind_list);
 
 	ret = snd_soc_register_platform(dev, &skl_platform_drv);
 	if (ret) {
@@ -1320,6 +1321,17 @@ int skl_platform_register(struct device *dev)
 
 int skl_platform_unregister(struct device *dev)
 {
+	struct hdac_ext_bus *ebus = dev_get_drvdata(dev);
+	struct skl *skl = ebus_to_skl(ebus);
+	struct skl_module_deferred_bind *modules;
+
+	if (!list_empty(&skl->bind_list)) {
+		list_for_each_entry(modules, &skl->bind_list, node) {
+			list_del(&modules->node);
+			kfree(modules);
+		}
+	}
+
 	snd_soc_unregister_component(dev);
 	snd_soc_unregister_platform(dev);
 	return 0;