reset: Add APIs to manage array of resets

Many devices may want to request a bunch of resets and control them. So
it's better to manage them as an array. Add APIs to _get() an array of
reset_control, reusing the _assert(), _deassert(), and _reset() APIs for
single reset controls. Since reset controls already may control multiple
reset lines with a single hardware bit, from the user perspective, reset
control arrays are not at all different from single reset controls.
Note that these APIs don't guarantee that the reset lines managed in the
array are handled in any particular order.

Cc: Felipe Balbi <balbi@kernel.org>
Cc: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>
[p.zabel@pengutronix.de: changed API to hide reset control arrays behind
 struct reset_control]
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

1 files changed, 68 insertions, 0 deletions

diff --git a/include/linux/reset.h b/include/linux/reset.h
index 13d8681..56463f3 100644
--- a/include/linux/reset.h
+++ b/include/linux/reset.h
@@ -25,6 +25,11 @@ struct reset_control *__devm_reset_control_get(struct device *dev,
 
 int __must_check device_reset(struct device *dev);
 
+struct reset_control *devm_reset_control_array_get(struct device *dev,
+						   bool shared, bool optional);
+struct reset_control *of_reset_control_array_get(struct device_node *np,
+						 bool shared, bool optional);
+
 static inline int device_reset_optional(struct device *dev)
 {
 	return device_reset(dev);
@@ -89,6 +94,18 @@ static inline struct reset_control *__devm_reset_control_get(
 	return optional ? NULL : ERR_PTR(-ENOTSUPP);
 }
 
+static inline struct reset_control *
+devm_reset_control_array_get(struct device *dev, bool shared, bool optional)
+{
+	return optional ? NULL : ERR_PTR(-ENOTSUPP);
+}
+
+static inline struct reset_control *
+of_reset_control_array_get(struct device_node *np, bool shared, bool optional)
+{
+	return optional ? NULL : ERR_PTR(-ENOTSUPP);
+}
+
 #endif /* CONFIG_RESET_CONTROLLER */
 
 /**
@@ -374,4 +391,55 @@ static inline struct reset_control *devm_reset_control_get_by_index(
 {
 	return devm_reset_control_get_exclusive_by_index(dev, index);
 }
+
+/*
+ * APIs to manage a list of reset controllers
+ */
+static inline struct reset_control *
+devm_reset_control_array_get_exclusive(struct device *dev)
+{
+	return devm_reset_control_array_get(dev, false, false);
+}
+
+static inline struct reset_control *
+devm_reset_control_array_get_shared(struct device *dev)
+{
+	return devm_reset_control_array_get(dev, true, false);
+}
+
+static inline struct reset_control *
+devm_reset_control_array_get_optional_exclusive(struct device *dev)
+{
+	return devm_reset_control_array_get(dev, false, true);
+}
+
+static inline struct reset_control *
+devm_reset_control_array_get_optional_shared(struct device *dev)
+{
+	return devm_reset_control_array_get(dev, true, true);
+}
+
+static inline struct reset_control *
+of_reset_control_array_get_exclusive(struct device_node *node)
+{
+	return of_reset_control_array_get(node, false, false);
+}
+
+static inline struct reset_control *
+of_reset_control_array_get_shared(struct device_node *node)
+{
+	return of_reset_control_array_get(node, true, false);
+}
+
+static inline struct reset_control *
+of_reset_control_array_get_optional_exclusive(struct device_node *node)
+{
+	return of_reset_control_array_get(node, false, true);
+}
+
+static inline struct reset_control *
+of_reset_control_array_get_optional_shared(struct device_node *node)
+{
+	return of_reset_control_array_get(node, true, true);
+}
 #endif