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authorAndrew Lunn <andrew@lunn.ch>2014-02-04 18:33:12 +0100
committerJason Cooper <jason@lakedaemon.net>2014-02-05 05:48:43 +0000
commit788a4d56ff378bff0b8e685d03a962b36903a149 (patch)
treed22d5b9e750448fb0d7695bf4c9360b326668a95 /Documentation
parent04c2facad8fee66c981a51852806d8923336f362 (diff)
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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>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/phy.txt20
1 files changed, 13 insertions, 7 deletions
diff --git a/Documentation/phy.txt b/Documentation/phy.txt
index 2e24b993e95f..ebff6ee52441 100644
--- a/Documentation/phy.txt
+++ b/Documentation/phy.txt
@@ -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);
-
-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.
+struct phy *devm_phy_optional_get(struct device *dev, const char *string);
+
+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,