[PATCH v4 2/2] reset: make optional functions really optional

From: Ramiro Oliveira
Date: Fri Jan 13 2017 - 12:58:09 EST


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>
---
drivers/reset/core.c | 49 +++++++++++++++++++++++++++++++++++++++----------
include/linux/reset.h | 45 ++++++++++++++++++++++++++-------------------
2 files changed, 65 insertions(+), 29 deletions(-)

diff --git a/drivers/reset/core.c b/drivers/reset/core.c
index 272c1e4ecb5c..c79cce3a7b6d 100644
--- a/drivers/reset/core.c
+++ b/drivers/reset/core.c
@@ -143,12 +143,18 @@ EXPORT_SYMBOL_GPL(devm_reset_controller_register);
* a no-op.
* Consumers must not use reset_control_(de)assert on shared reset lines when
* reset_control_reset has been used.
+ *
+ * If rstc is NULL it is an optional reset and the function will just
+ * return 0.
*/
int reset_control_reset(struct reset_control *rstc)
{
int ret;

- if (WARN_ON(IS_ERR_OR_NULL(rstc)))
+ if (!rstc)
+ return 0;
+
+ if (WARN_ON(IS_ERR(rstc)))
return -EINVAL;

if (!rstc->rcdev->ops->reset)
@@ -182,10 +188,17 @@ EXPORT_SYMBOL_GPL(reset_control_reset);
* internal state to be reset, but must be prepared for this to happen.
* Consumers must not use reset_control_reset on shared reset lines when
* reset_control_(de)assert has been used.
+ * return 0.
+ *
+ * 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)
@@ -213,10 +226,17 @@ EXPORT_SYMBOL_GPL(reset_control_assert);
* After calling this function, the reset is guaranteed to be deasserted.
* Consumers must not use reset_control_reset on shared reset lines when
* reset_control_(de)assert has been used.
+ * return 0.
+ *
+ * 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)
@@ -237,12 +257,15 @@ 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)
@@ -299,7 +322,8 @@ static void __reset_control_put(struct reset_control *rstc)
}

struct reset_control *__of_reset_control_get(struct device_node *node,
- const char *id, int index, bool shared)
+ const char *id, int index, bool shared,
+ bool optional)
{
struct reset_control *rstc;
struct reset_controller_dev *r, *rcdev;
@@ -313,14 +337,18 @@ struct reset_control *__of_reset_control_get(struct device_node *node,
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;
@@ -379,7 +407,8 @@ static void devm_reset_control_release(struct device *dev, void *res)
}

struct reset_control *__devm_reset_control_get(struct device *dev,
- const char *id, int index, bool shared)
+ const char *id, int index, bool shared,
+ bool optional)
{
struct reset_control **ptr, *rstc;

@@ -389,7 +418,7 @@ struct reset_control *__devm_reset_control_get(struct device *dev,
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);
diff --git a/include/linux/reset.h b/include/linux/reset.h
index ec1d1fd28f5f..86b4ed75359e 100644
--- a/include/linux/reset.h
+++ b/include/linux/reset.h
@@ -13,10 +13,12 @@ int reset_control_deassert(struct reset_control *rstc);
int reset_control_status(struct reset_control *rstc);

struct reset_control *__of_reset_control_get(struct device_node *node,
- const char *id, int index, bool 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, bool 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(struct device *dev)

static inline struct reset_control *__of_reset_control_get(
struct device_node *node,
- const char *id, int index, bool 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, bool 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(struct device *dev, const char *id)
#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(struct device *dev, const char *id)
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, true);
+ 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, false);
+ 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, true);
+ return __of_reset_control_get(dev ? dev->of_node : NULL, id, 0, true,
+ true);
}

/**
@@ -160,7 +167,7 @@ static inline struct reset_control *reset_control_get_optional_shared(
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_reset_control_get_exclusive(
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, true);
+ return __of_reset_control_get(node, id, 0, true, false);
}

/**
@@ -202,7 +209,7 @@ static inline struct reset_control *of_reset_control_get_shared(
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, false);
+ return __of_reset_control_get(node, NULL, index, false, false);
}

/**
@@ -230,7 +237,7 @@ static inline struct reset_control *of_reset_control_get_exclusive_by_index(
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, true);
+ return __of_reset_control_get(node, NULL, index, true, false);
}

/**
@@ -252,7 +259,7 @@ __must_check devm_reset_control_get_exclusive(struct device *dev,
#ifndef CONFIG_RESET_CONTROLLER
WARN_ON(1);
#endif
- return __devm_reset_control_get(dev, id, 0, false);
+ return __devm_reset_control_get(dev, id, 0, false, false);
}

/**
@@ -267,19 +274,19 @@ __must_check devm_reset_control_get_exclusive(struct device *dev,
static inline struct reset_control *devm_reset_control_get_shared(
struct device *dev, const char *id)
{
- return __devm_reset_control_get(dev, id, 0, true);
+ 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, false);
+ 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, true);
+ return __devm_reset_control_get(dev, id, 0, true, true);
}

/**
@@ -297,7 +304,7 @@ static inline struct reset_control *devm_reset_control_get_optional_shared(
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, false);
+ return __devm_reset_control_get(dev, NULL, index, false, false);
}

/**
@@ -313,7 +320,7 @@ devm_reset_control_get_exclusive_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, true);
+ return __devm_reset_control_get(dev, NULL, index, true, false);
}

/*
--
2.11.0