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authorStephen Warren <swarren@nvidia.com>2012-02-22 14:25:58 -0700
committerLinus Walleij <linus.walleij@linaro.org>2012-02-24 06:24:52 +0100
commit1681f5ae4ca25bddb6f7b6d4f463cc83e3d1ad01 (patch)
treefc37580130beadbc5e0898ddb9b5fec32b662859 /Documentation/pinctrl.txt
parentf7b9006f4598dd252dca5225f3cf88179c36276f (diff)
pinctrl: disallow map table entries with NULL dev_name field
Hog entries are mapping table entries with .ctrl_dev_name == .dev_name. All other mapping table entries need .dev_name set so that they will match some pinctrl_get() call. All extant PIN_MAP*() macros set .dev_name. So, there is no reason to allow mapping table entries without .dev_name set. Update the code and documentation to disallow this. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'Documentation/pinctrl.txt')
-rw-r--r--Documentation/pinctrl.txt15
1 files changed, 5 insertions, 10 deletions
diff --git a/Documentation/pinctrl.txt b/Documentation/pinctrl.txt
index ee3266b948e..fa9163af34f 100644
--- a/Documentation/pinctrl.txt
+++ b/Documentation/pinctrl.txt
@@ -494,14 +494,10 @@ Definitions:
{"map-i2c0", i2c0, pinctrl0, fi2c0, gi2c0}
}
- Every map must be assigned a symbolic name, pin controller and function.
- The group is not compulsory - if it is omitted the first group presented by
- the driver as applicable for the function will be selected, which is
- useful for simple cases.
-
- The device name is present in map entries tied to specific devices. Maps
- without device names are referred to as SYSTEM pinmuxes, such as can be taken
- by the machine implementation on boot and not tied to any specific device.
+ Every map must be assigned a state name, pin controller, device and
+ function. The group is not compulsory - if it is omitted the first group
+ presented by the driver as applicable for the function will be selected,
+ which is useful for simple cases.
It is possible to map several groups to the same combination of device,
pin controller and function. This is for cases where a certain function on
@@ -983,8 +979,7 @@ after this you should be able to see this in the debugfs listing of all pins.
System pin control hogging
==========================
-A system pin control map entry, i.e. a pin control setting that does not have
-a device associated with it, can be hogged by the core when the pin controller
+Pin control map entries can be hogged by the core when the pin controller
is registered. This means that the core will attempt to call pinctrl_get() and
pinctrl_enable() on it immediately after the pin control device has been
registered.