Merge tag 'mfd-fixes-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd

Pull MFD fixes from Lee Jones:
 "Contained are some standard fixes and unusually an extension to the
  Reset API.  Some of those changes are required to fix a bug introduced
  in -rc1, which introduces extra 'reset line checks' i.e. whether the
  line is shared or not.  If a line is shared and the new *_shared() API
  is not used, the request fails with an error.  This breaks USB in v4.7
  for ST's platforms.

  Admittedly, there are some patches contained in our (MFD/Reset)
  immutable branch which are not true -fixes, but there isn't anything I
  can do about that.  Rest assured though, there aren't any API
  'changes'.  Everything is the same from the consumer's perspective.

   - Use new reset_*_get_shared() variant to prevent reset line
     obtainment failure (Fixes commit 0b52297f2288: "reset: Add support
     for shared reset controls")

   - Fix unintentional switch() fall-through into error path

   - Fix uninitialised variable compiler warning"

* tag 'mfd-fixes-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd:
  mfd: da9053: Fix compiler warning message for uninitialised variable
  mfd: max77620: Fix FPS switch statements
  phy: phy-stih407-usb: Inform the reset framework that our reset line may be shared
  usb: dwc3: st: Inform the reset framework that our reset line may be shared
  usb: host: ehci-st: Inform the reset framework that our reset line may be shared
  usb: host: ohci-st: Inform the reset framework that our reset line may be shared
  reset: TRIVIAL: Add line break at same place for similar APIs
  reset: Supply *_shared variant calls when using *_optional APIs
  reset: Supply *_shared variant calls when using of_* API
  reset: Ensure drivers are explicit when requesting reset lines
  reset: Reorder inline reset_control_get*() wrappers

2 files changed, 168 insertions, 45 deletions

diff --git a/include/linux/mfd/da9052/da9052.h b/include/linux/mfd/da9052/da9052.h
index c18a4c19d6fc..ce9230af09c2 100644
--- a/include/linux/mfd/da9052/da9052.h
+++ b/include/linux/mfd/da9052/da9052.h
@@ -171,7 +171,7 @@ static inline int da9052_group_read(struct da9052 *da9052, unsigned char reg,
 static inline int da9052_group_write(struct da9052 *da9052, unsigned char reg,
 				      unsigned reg_cnt, unsigned char *val)
 {
-	int ret;
+	int ret = 0;
 	int i;
 
 	for (i = 0; i < reg_cnt; i++) {
diff --git a/include/linux/reset.h b/include/linux/reset.h
index ec0306ce7b92..45a4abeb6acb 100644
--- a/include/linux/reset.h
+++ b/include/linux/reset.h
@@ -84,8 +84,8 @@ static inline struct reset_control *__devm_reset_control_get(
 #endif /* CONFIG_RESET_CONTROLLER */
 
 /**
- * reset_control_get - Lookup and obtain an exclusive reference to a
- *                     reset controller.
+ * reset_control_get_exclusive - Lookup and obtain an exclusive reference
+ *                               to a reset controller.
  * @dev: device to be reset by the controller
  * @id: reset line name
  *
@@ -98,8 +98,8 @@ static inline struct reset_control *__devm_reset_control_get(
  *
  * Use of id names is optional.
  */
-static inline struct reset_control *__must_check reset_control_get(
-					struct device *dev, const char *id)
+static inline struct reset_control *
+__must_check reset_control_get_exclusive(struct device *dev, const char *id)
 {
 #ifndef CONFIG_RESET_CONTROLLER
 	WARN_ON(1);
@@ -107,12 +107,6 @@ static inline struct reset_control *__must_check reset_control_get(
 	return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, 0);
 }
 
-static inline struct reset_control *reset_control_get_optional(
-					struct device *dev, const char *id)
-{
-	return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, 0);
-}
-
 /**
  * reset_control_get_shared - Lookup and obtain a shared reference to a
  *                            reset controller.
@@ -141,9 +135,21 @@ static inline struct reset_control *reset_control_get_shared(
 	return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, 1);
 }
 
+static inline struct reset_control *reset_control_get_optional_exclusive(
+					struct device *dev, const char *id)
+{
+	return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, 0);
+}
+
+static inline struct reset_control *reset_control_get_optional_shared(
+					struct device *dev, const char *id)
+{
+	return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, 1);
+}
+
 /**
- * of_reset_control_get - Lookup and obtain an exclusive reference to a
- *                        reset controller.
+ * of_reset_control_get_exclusive - Lookup and obtain an exclusive reference
+ *                                  to a reset controller.
  * @node: device to be reset by the controller
  * @id: reset line name
  *
@@ -151,15 +157,41 @@ static inline struct reset_control *reset_control_get_shared(
  *
  * Use of id names is optional.
  */
-static inline struct reset_control *of_reset_control_get(
+static inline struct reset_control *of_reset_control_get_exclusive(
 				struct device_node *node, const char *id)
 {
 	return __of_reset_control_get(node, id, 0, 0);
 }
 
 /**
- * of_reset_control_get_by_index - Lookup and obtain an exclusive reference to
- *                                 a reset controller by index.
+ * of_reset_control_get_shared - Lookup and obtain an shared reference
+ *                               to a reset controller.
+ * @node: device to be reset by the controller
+ * @id: reset line name
+ *
+ * When a reset-control is shared, the behavior of reset_control_assert /
+ * deassert is changed, the reset-core will keep track of a deassert_count
+ * and only (re-)assert the reset after reset_control_assert has been called
+ * as many times as reset_control_deassert was called. Also see the remark
+ * about shared reset-controls in the reset_control_assert docs.
+ *
+ * Calling reset_control_assert without first calling reset_control_deassert
+ * is not allowed on a shared reset control. Calling reset_control_reset is
+ * also not allowed on a shared reset control.
+ * Returns a struct reset_control or IS_ERR() condition containing errno.
+ *
+ * Use of id names is optional.
+ */
+static inline struct reset_control *of_reset_control_get_shared(
+				struct device_node *node, const char *id)
+{
+	return __of_reset_control_get(node, id, 0, 1);
+}
+
+/**
+ * of_reset_control_get_exclusive_by_index - Lookup and obtain an exclusive
+ *                                           reference to a reset controller
+ *                                           by index.
  * @node: device to be reset by the controller
  * @index: index of the reset controller
  *
@@ -167,49 +199,60 @@ static inline struct reset_control *of_reset_control_get(
  * in whatever order. Returns a struct reset_control or IS_ERR() condition
  * containing errno.
  */
-static inline struct reset_control *of_reset_control_get_by_index(
+static inline struct reset_control *of_reset_control_get_exclusive_by_index(
 					struct device_node *node, int index)
 {
 	return __of_reset_control_get(node, NULL, index, 0);
 }
 
 /**
- * devm_reset_control_get - resource managed reset_control_get()
- * @dev: device to be reset by the controller
- * @id: reset line name
+ * of_reset_control_get_shared_by_index - Lookup and obtain an shared
+ *                                        reference to a reset controller
+ *                                        by index.
+ * @node: device to be reset by the controller
+ * @index: index of the reset controller
+ *
+ * When a reset-control is shared, the behavior of reset_control_assert /
+ * deassert is changed, the reset-core will keep track of a deassert_count
+ * and only (re-)assert the reset after reset_control_assert has been called
+ * as many times as reset_control_deassert was called. Also see the remark
+ * about shared reset-controls in the reset_control_assert docs.
+ *
+ * Calling reset_control_assert without first calling reset_control_deassert
+ * is not allowed on a shared reset control. Calling reset_control_reset is
+ * also not allowed on a shared reset control.
+ * Returns a struct reset_control or IS_ERR() condition containing errno.
  *
- * Managed reset_control_get(). For reset controllers returned from this
- * function, reset_control_put() is called automatically on driver detach.
- * See reset_control_get() for more information.
+ * This is to be used to perform a list of resets for a device or power domain
+ * in whatever order. Returns a struct reset_control or IS_ERR() condition
+ * containing errno.
  */
-static inline struct reset_control *__must_check devm_reset_control_get(
-					struct device *dev, const char *id)
-{
-#ifndef CONFIG_RESET_CONTROLLER
-	WARN_ON(1);
-#endif
-	return __devm_reset_control_get(dev, id, 0, 0);
-}
-
-static inline struct reset_control *devm_reset_control_get_optional(
-					struct device *dev, const char *id)
+static inline struct reset_control *of_reset_control_get_shared_by_index(
+					struct device_node *node, int index)
 {
-	return __devm_reset_control_get(dev, id, 0, 0);
+	return __of_reset_control_get(node, NULL, index, 1);
 }
 
 /**
- * devm_reset_control_get_by_index - resource managed reset_control_get
+ * devm_reset_control_get_exclusive - resource managed
+ *                                    reset_control_get_exclusive()
  * @dev: device to be reset by the controller
- * @index: index of the reset controller
+ * @id: reset line name
  *
- * Managed reset_control_get(). For reset controllers returned from this
- * function, reset_control_put() is called automatically on driver detach.
- * See reset_control_get() for more information.
+ * Managed reset_control_get_exclusive(). For reset controllers returned
+ * from this function, reset_control_put() is called automatically on driver
+ * detach.
+ *
+ * See reset_control_get_exclusive() for more information.
  */
-static inline struct reset_control *devm_reset_control_get_by_index(
-					struct device *dev, int index)
+static inline struct reset_control *
+__must_check devm_reset_control_get_exclusive(struct device *dev,
+					      const char *id)
 {
-	return __devm_reset_control_get(dev, NULL, index, 0);
+#ifndef CONFIG_RESET_CONTROLLER
+	WARN_ON(1);
+#endif
+	return __devm_reset_control_get(dev, id, 0, 0);
 }
 
 /**
@@ -227,6 +270,36 @@ static inline struct reset_control *devm_reset_control_get_shared(
 	return __devm_reset_control_get(dev, id, 0, 1);
 }
 
+static inline struct reset_control *devm_reset_control_get_optional_exclusive(
+					struct device *dev, const char *id)
+{
+	return __devm_reset_control_get(dev, id, 0, 0);
+}
+
+static inline struct reset_control *devm_reset_control_get_optional_shared(
+					struct device *dev, const char *id)
+{
+	return __devm_reset_control_get(dev, id, 0, 1);
+}
+
+/**
+ * devm_reset_control_get_exclusive_by_index - resource managed
+ *                                             reset_control_get_exclusive()
+ * @dev: device to be reset by the controller
+ * @index: index of the reset controller
+ *
+ * Managed reset_control_get_exclusive(). For reset controllers returned from
+ * this function, reset_control_put() is called automatically on driver
+ * detach.
+ *
+ * See reset_control_get_exclusive() for more information.
+ */
+static inline struct reset_control *
+devm_reset_control_get_exclusive_by_index(struct device *dev, int index)
+{
+	return __devm_reset_control_get(dev, NULL, index, 0);
+}
+
 /**
  * devm_reset_control_get_shared_by_index - resource managed
  * reset_control_get_shared
@@ -237,10 +310,60 @@ static inline struct reset_control *devm_reset_control_get_shared(
  * this function, reset_control_put() is called automatically on driver detach.
  * See reset_control_get_shared() for more information.
  */
-static inline struct reset_control *devm_reset_control_get_shared_by_index(
-					struct device *dev, int index)
+static inline struct reset_control *
+devm_reset_control_get_shared_by_index(struct device *dev, int index)
 {
 	return __devm_reset_control_get(dev, NULL, index, 1);
 }
 
+/*
+ * TEMPORARY calls to use during transition:
+ *
+ *   of_reset_control_get() => of_reset_control_get_exclusive()
+ *
+ * These inline function calls will be removed once all consumers
+ * have been moved over to the new explicit API.
+ */
+static inline struct reset_control *reset_control_get(
+				struct device *dev, const char *id)
+{
+	return reset_control_get_exclusive(dev, id);
+}
+
+static inline struct reset_control *reset_control_get_optional(
+					struct device *dev, const char *id)
+{
+	return reset_control_get_optional_exclusive(dev, id);
+}
+
+static inline struct reset_control *of_reset_control_get(
+				struct device_node *node, const char *id)
+{
+	return of_reset_control_get_exclusive(node, id);
+}
+
+static inline struct reset_control *of_reset_control_get_by_index(
+				struct device_node *node, int index)
+{
+	return of_reset_control_get_exclusive_by_index(node, index);
+}
+
+static inline struct reset_control *devm_reset_control_get(
+				struct device *dev, const char *id)
+{
+	return devm_reset_control_get_exclusive(dev, id);
+}
+
+static inline struct reset_control *devm_reset_control_get_optional(
+				struct device *dev, const char *id)
+{
+	return devm_reset_control_get_optional_exclusive(dev, id);
+
+}
+
+static inline struct reset_control *devm_reset_control_get_by_index(
+				struct device *dev, int index)
+{
+	return devm_reset_control_get_exclusive_by_index(dev, index);
+}
 #endif