drivers: phy: Add support for optional phys

Add devm_phy_optional_get and phy_optional_get, which should be used
when the phy is optional. They does not return an error when the phy
does not exist, rather they returns NULL, which is considered as a valid
phy, but results in NOPs when used with the consumer API.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
This commit is contained in:
Andrew Lunn 2014-02-04 18:33:12 +01:00 коммит произвёл Jason Cooper
Родитель 04c2facad8
Коммит 788a4d56ff
3 изменённых файлов: 71 добавлений и 6 удалений

Просмотреть файл

@ -75,14 +75,20 @@ Before the controller can make use of the PHY, it has to get a reference to
it. This framework provides the following APIs to get a reference to the PHY.
struct phy *phy_get(struct device *dev, const char *string);
struct phy *phy_optional_get(struct device *dev, const char *string);
struct phy *devm_phy_get(struct device *dev, const char *string);
struct phy *devm_phy_optional_get(struct device *dev, const char *string);
phy_get and devm_phy_get can be used to get the PHY. In the case of dt boot,
the string arguments should contain the phy name as given in the dt data and
in the case of non-dt boot, it should contain the label of the PHY.
The only difference between the two APIs is that devm_phy_get associates the
device with the PHY using devres on successful PHY get. On driver detach,
release function is invoked on the the devres data and devres data is freed.
phy_get, phy_optional_get, devm_phy_get and devm_phy_optional_get can
be used to get the PHY. In the case of dt boot, the string arguments
should contain the phy name as given in the dt data and in the case of
non-dt boot, it should contain the label of the PHY. The two
devm_phy_get associates the device with the PHY using devres on
successful PHY get. On driver detach, release function is invoked on
the the devres data and devres data is freed. phy_optional_get and
devm_phy_optional_get should be used when the phy is optional. These
two functions will never return -ENODEV, but instead returns NULL when
the phy cannot be found.
It should be noted that NULL is a valid phy reference. All phy
consumer calls on the NULL phy become NOPs. That is the release calls,

Просмотреть файл

@ -425,6 +425,27 @@ struct phy *phy_get(struct device *dev, const char *string)
}
EXPORT_SYMBOL_GPL(phy_get);
/**
* phy_optional_get() - lookup and obtain a reference to an optional phy.
* @dev: device that requests this phy
* @string: the phy name as given in the dt data or the name of the controller
* port for non-dt case
*
* Returns the phy driver, after getting a refcount to it; or
* NULL if there is no such phy. The caller is responsible for
* calling phy_put() to release that count.
*/
struct phy *phy_optional_get(struct device *dev, const char *string)
{
struct phy *phy = phy_get(dev, string);
if (PTR_ERR(phy) == -ENODEV)
phy = NULL;
return phy;
}
EXPORT_SYMBOL_GPL(phy_optional_get);
/**
* devm_phy_get() - lookup and obtain a reference to a phy.
* @dev: device that requests this phy
@ -455,6 +476,30 @@ struct phy *devm_phy_get(struct device *dev, const char *string)
}
EXPORT_SYMBOL_GPL(devm_phy_get);
/**
* devm_phy_optional_get() - lookup and obtain a reference to an optional phy.
* @dev: device that requests this phy
* @string: the phy name as given in the dt data or phy device name
* for non-dt case
*
* Gets the phy using phy_get(), and associates a device with it using
* devres. On driver detach, release function is invoked on the devres
* data, then, devres data is freed. This differs to devm_phy_get() in
* that if the phy does not exist, it is not considered an error and
* -ENODEV will not be returned. Instead the NULL phy is returned,
* which can be passed to all other phy consumer calls.
*/
struct phy *devm_phy_optional_get(struct device *dev, const char *string)
{
struct phy *phy = devm_phy_get(dev, string);
if (PTR_ERR(phy) == -ENODEV)
phy = NULL;
return phy;
}
EXPORT_SYMBOL_GPL(devm_phy_optional_get);
/**
* phy_create() - create a new phy
* @dev: device that is creating the new phy

Просмотреть файл

@ -146,7 +146,9 @@ static inline void phy_set_bus_width(struct phy *phy, int bus_width)
phy->attrs.bus_width = bus_width;
}
struct phy *phy_get(struct device *dev, const char *string);
struct phy *phy_optional_get(struct device *dev, const char *string);
struct phy *devm_phy_get(struct device *dev, const char *string);
struct phy *devm_phy_optional_get(struct device *dev, const char *string);
void phy_put(struct phy *phy);
void devm_phy_put(struct device *dev, struct phy *phy);
struct phy *of_phy_simple_xlate(struct device *dev,
@ -232,11 +234,23 @@ static inline struct phy *phy_get(struct device *dev, const char *string)
return ERR_PTR(-ENOSYS);
}
static inline struct phy *phy_optional_get(struct device *dev,
const char *string)
{
return ERR_PTR(-ENOSYS);
}
static inline struct phy *devm_phy_get(struct device *dev, const char *string)
{
return ERR_PTR(-ENOSYS);
}
static inline struct phy *devm_phy_optional_get(struct device *dev,
const char *string)
{
return ERR_PTR(-ENOSYS);
}
static inline void phy_put(struct phy *phy)
{
}