4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ramiro Oliveira <Ramiro.Oliveira@xxxxxxxxxxxx> commit bb475230b8e59a547ab66ac3b02572df21a580e9 upstream. The *_get_optional_* functions weren't really optional so this patch makes them really optional. These *_get_optional_* functions will now return NULL instead of an error if no matching reset phandle is found in the DT, and all the reset_control_* functions now accept NULL rstc pointers. Signed-off-by: Ramiro Oliveira <Ramiro.Oliveira@xxxxxxxxxxxx> Signed-off-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> Cc: Dinh Nguyen <dinguyen@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/reset/core.c | 48 +++++++++++++++++++++++++++++++++++++----------- include/linux/reset.h | 45 ++++++++++++++++++++++++++------------------- 2 files changed, 63 insertions(+), 30 deletions(-) --- a/drivers/reset/core.c +++ b/drivers/reset/core.c @@ -135,11 +135,16 @@ EXPORT_SYMBOL_GPL(devm_reset_controller_ * @rstc: reset controller * * Calling this on a shared reset controller is an error. + * + * If rstc is NULL it is an optional reset and the function will just + * return 0. */ int reset_control_reset(struct reset_control *rstc) { - if (WARN_ON(IS_ERR_OR_NULL(rstc)) || - WARN_ON(rstc->shared)) + if (!rstc) + return 0; + + if (WARN_ON(IS_ERR(rstc))) return -EINVAL; if (rstc->rcdev->ops->reset) @@ -159,10 +164,16 @@ EXPORT_SYMBOL_GPL(reset_control_reset); * * For shared reset controls a driver cannot expect the hw's registers and * internal state to be reset, but must be prepared for this to happen. + * + * If rstc is NULL it is an optional reset and the function will just + * return 0. */ int reset_control_assert(struct reset_control *rstc) { - if (WARN_ON(IS_ERR_OR_NULL(rstc))) + if (!rstc) + return 0; + + if (WARN_ON(IS_ERR(rstc))) return -EINVAL; if (!rstc->rcdev->ops->assert) @@ -185,10 +196,16 @@ EXPORT_SYMBOL_GPL(reset_control_assert); * @rstc: reset controller * * After calling this function, the reset is guaranteed to be deasserted. + * + * If rstc is NULL it is an optional reset and the function will just + * return 0. */ int reset_control_deassert(struct reset_control *rstc) { - if (WARN_ON(IS_ERR_OR_NULL(rstc))) + if (!rstc) + return 0; + + if (WARN_ON(IS_ERR(rstc))) return -EINVAL; if (!rstc->rcdev->ops->deassert) @@ -206,12 +223,15 @@ EXPORT_SYMBOL_GPL(reset_control_deassert /** * reset_control_status - returns a negative errno if not supported, a * positive value if the reset line is asserted, or zero if the reset - * line is not asserted. + * line is not asserted or if the desc is NULL (optional reset). * @rstc: reset controller */ int reset_control_status(struct reset_control *rstc) { - if (WARN_ON(IS_ERR_OR_NULL(rstc))) + if (!rstc) + return 0; + + if (WARN_ON(IS_ERR(rstc))) return -EINVAL; if (rstc->rcdev->ops->status) @@ -268,7 +288,8 @@ static void __reset_control_put(struct r } struct reset_control *__of_reset_control_get(struct device_node *node, - const char *id, int index, int shared) + const char *id, int index, bool shared, + bool optional) { struct reset_control *rstc; struct reset_controller_dev *r, *rcdev; @@ -282,14 +303,18 @@ struct reset_control *__of_reset_control if (id) { index = of_property_match_string(node, "reset-names", id); + if (index == -EILSEQ) + return ERR_PTR(index); if (index < 0) - return ERR_PTR(-ENOENT); + return optional ? NULL : ERR_PTR(-ENOENT); } ret = of_parse_phandle_with_args(node, "resets", "#reset-cells", index, &args); - if (ret) + if (ret == -EINVAL) return ERR_PTR(ret); + if (ret) + return optional ? NULL : ERR_PTR(ret); mutex_lock(&reset_list_mutex); rcdev = NULL; @@ -348,7 +373,8 @@ static void devm_reset_control_release(s } struct reset_control *__devm_reset_control_get(struct device *dev, - const char *id, int index, int shared) + const char *id, int index, bool shared, + bool optional) { struct reset_control **ptr, *rstc; @@ -358,7 +384,7 @@ struct reset_control *__devm_reset_contr return ERR_PTR(-ENOMEM); rstc = __of_reset_control_get(dev ? dev->of_node : NULL, - id, index, shared); + id, index, shared, optional); if (!IS_ERR(rstc)) { *ptr = rstc; devres_add(dev, ptr); --- a/include/linux/reset.h +++ b/include/linux/reset.h @@ -13,10 +13,12 @@ int reset_control_deassert(struct reset_ int reset_control_status(struct reset_control *rstc); struct reset_control *__of_reset_control_get(struct device_node *node, - const char *id, int index, int shared); + const char *id, int index, bool shared, + bool optional); void reset_control_put(struct reset_control *rstc); struct reset_control *__devm_reset_control_get(struct device *dev, - const char *id, int index, int shared); + const char *id, int index, bool shared, + bool optional); int __must_check device_reset(struct device *dev); @@ -69,14 +71,15 @@ static inline int device_reset_optional( static inline struct reset_control *__of_reset_control_get( struct device_node *node, - const char *id, int index, int shared) + const char *id, int index, bool shared, + bool optional) { return ERR_PTR(-ENOTSUPP); } static inline struct reset_control *__devm_reset_control_get( - struct device *dev, - const char *id, int index, int shared) + struct device *dev, const char *id, + int index, bool shared, bool optional) { return ERR_PTR(-ENOTSUPP); } @@ -104,7 +107,8 @@ __must_check reset_control_get_exclusive #ifndef CONFIG_RESET_CONTROLLER WARN_ON(1); #endif - return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, 0); + return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, false, + false); } /** @@ -132,19 +136,22 @@ __must_check reset_control_get_exclusive static inline struct reset_control *reset_control_get_shared( struct device *dev, const char *id) { - return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, 1); + return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, true, + false); } 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); + return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, false, + true); } 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); + return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, true, + true); } /** @@ -160,7 +167,7 @@ static inline struct reset_control *rese 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); + return __of_reset_control_get(node, id, 0, false, false); } /** @@ -185,7 +192,7 @@ static inline struct reset_control *of_r 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); + return __of_reset_control_get(node, id, 0, true, false); } /** @@ -202,7 +209,7 @@ static inline struct reset_control *of_r 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); + return __of_reset_control_get(node, NULL, index, false, false); } /** @@ -230,7 +237,7 @@ static inline struct reset_control *of_r static inline struct reset_control *of_reset_control_get_shared_by_index( struct device_node *node, int index) { - return __of_reset_control_get(node, NULL, index, 1); + return __of_reset_control_get(node, NULL, index, true, false); } /** @@ -252,7 +259,7 @@ __must_check devm_reset_control_get_excl #ifndef CONFIG_RESET_CONTROLLER WARN_ON(1); #endif - return __devm_reset_control_get(dev, id, 0, 0); + return __devm_reset_control_get(dev, id, 0, false, false); } /** @@ -267,19 +274,19 @@ __must_check devm_reset_control_get_excl static inline struct reset_control *devm_reset_control_get_shared( struct device *dev, const char *id) { - return __devm_reset_control_get(dev, id, 0, 1); + return __devm_reset_control_get(dev, id, 0, true, false); } 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); + return __devm_reset_control_get(dev, id, 0, false, true); } 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); + return __devm_reset_control_get(dev, id, 0, true, true); } /** @@ -297,7 +304,7 @@ static inline struct reset_control *devm 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); + return __devm_reset_control_get(dev, NULL, index, false, false); } /** @@ -313,7 +320,7 @@ devm_reset_control_get_exclusive_by_inde 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); + return __devm_reset_control_get(dev, NULL, index, true, false); } /*