1 files changed, 47 insertions, 1 deletions

diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c
index 145dcc0..36c4c340 100644
--- a/drivers/bus/ti-sysc.c
+++ b/drivers/bus/ti-sysc.c
@@ -19,6 +19,7 @@
 #include <linux/platform_device.h>
 #include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
+#include <linux/reset.h>
 #include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/slab.h>
@@ -74,6 +75,7 @@ struct sysc {
 	struct clk **clocks;
 	const char **clock_roles;
 	int nr_clocks;
+	struct reset_control *rsts;
 	const char *legacy_mode;
 	const struct sysc_capabilities *cap;
 	struct sysc_config cfg;
@@ -214,6 +216,42 @@ static int sysc_get_clocks(struct sysc *ddata)
 }
 
 /**
+ * sysc_init_resets - reset module on init
+ * @ddata: device driver data
+ *
+ * A module can have both OCP softreset control and external rstctrl.
+ * If more complicated rstctrl resets are needed, please handle these
+ * directly from the child device driver and map only the module reset
+ * for the parent interconnect target module device.
+ *
+ * Automatic reset of the module on init can be skipped with the
+ * "ti,no-reset-on-init" device tree property.
+ */
+static int sysc_init_resets(struct sysc *ddata)
+{
+	int error;
+
+	ddata->rsts =
+		devm_reset_control_array_get_optional_exclusive(ddata->dev);
+	if (IS_ERR(ddata->rsts))
+		return PTR_ERR(ddata->rsts);
+
+	if (ddata->cfg.quirks & SYSC_QUIRK_NO_RESET_ON_INIT)
+		goto deassert;
+
+	error = reset_control_assert(ddata->rsts);
+	if (error)
+		return error;
+
+deassert:
+	error = reset_control_deassert(ddata->rsts);
+	if (error)
+		return error;
+
+	return 0;
+}
+
+/**
  * sysc_parse_and_check_child_range - parses module IO region from ranges
  * @ddata: device driver data
  *
@@ -889,6 +927,7 @@ static int sysc_init_module(struct sysc *ddata)
 
 		return 0;
 	}
+
 	ddata->revision = sysc_read_revision(ddata);
 	pm_runtime_put_sync(ddata->dev);
 
@@ -1583,8 +1622,11 @@ static int sysc_probe(struct platform_device *pdev)
 	if (error)
 		goto unprepare;
 
-	pm_runtime_enable(ddata->dev);
+	error = sysc_init_resets(ddata);
+	if (error)
+		return error;
 
+	pm_runtime_enable(ddata->dev);
 	error = sysc_init_module(ddata);
 	if (error)
 		goto unprepare;
@@ -1615,6 +1657,9 @@ static int sysc_probe(struct platform_device *pdev)
 		pm_runtime_put(&pdev->dev);
 	}
 
+	if (!of_get_available_child_count(ddata->dev->of_node))
+		reset_control_assert(ddata->rsts);
+
 	return 0;
 
 err:
@@ -1644,6 +1689,7 @@ static int sysc_remove(struct platform_device *pdev)
 
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
+	reset_control_assert(ddata->rsts);
 
 unprepare:
 	sysc_unprepare(ddata);