svn commit: r356772 - stable/12/sys/dev/extres/regulator

[Kyle Evans]

Author: kevans
Date: Thu Jan 16 03:14:01 2020
New Revision: 356772
URL: https://svnweb.freebsd.org/changeset/base/356772

Log:
  MFC r356649: regulator: small enhancements to regulator_shutdown
  
  Highlights:
  
  - Exit early if we're not disabling unused regulators; there's no need to
    take the regulator topology lock and re-evaluate this every iteration, as
    it's not going to change.
  - Don't emit a notice that we're shutting down a regulator if it's not
    enabled, to reduce noise.
  - Mention the outcome of the shutdown, to aide debugging and easily let
    developer/user collect list of regulators we actually shutdown to
    determine problematic one.

Modified:
  stable/12/sys/dev/extres/regulator/regulator.c
Directory Properties:
  stable/12/   (props changed)

Modified: stable/12/sys/dev/extres/regulator/regulator.c
==============================================================================
--- stable/12/sys/dev/extres/regulator/regulator.c	Thu Jan 16 03:11:25 2020	(r356771)
+++ stable/12/sys/dev/extres/regulator/regulator.c	Thu Jan 16 03:14:01 2020	(r356772)
@@ -191,16 +191,36 @@ regulator_shutdown(void *dummy)
 	int status, ret;
 	int disable = 1;
 
-	REG_TOPO_SLOCK();
 	TUNABLE_INT_FETCH("hw.regulator.disable_unused", &disable);
+	if (!disable)
+		return;
+	REG_TOPO_SLOCK();
+
+	if (bootverbose)
+		printf("regulator: shutting down unused regulators\n");
 	TAILQ_FOREACH(entry, &regnode_list, reglist_link) {
-		if (!entry->std_param.always_on && disable) {
-			if (bootverbose)
-				printf("regulator: shutting down %s\n",
-				    entry->name);
+		if (!entry->std_param.always_on) {
 			ret = regnode_status(entry, &status);
-			if (ret == 0 && status == REGULATOR_STATUS_ENABLED)
-				regnode_stop(entry, 0);
+			if (ret == 0 && status == REGULATOR_STATUS_ENABLED) {
+				if (bootverbose)
+					printf("regulator: shutting down %s... ",
+					    entry->name);
+				ret = regnode_stop(entry, 0);
+				if (bootverbose) {
+					/*
+					 * Call out busy in particular, here,
+					 * because it's not unexpected to fail
+					 * shutdown if the regulator is simply
+					 * in-use.
+					 */
+					if (ret == EBUSY)
+						printf("busy\n");
+					else if (ret != 0)
+						printf("error (%d)\n", ret);
+					else
+						printf("ok\n");
+				}
+			}
 		}
 	}
 	REG_TOPO_UNLOCK();