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authorThomas Chou <thomas@wytron.com.tw>2015-10-21 21:33:45 +0800
committerThomas Chou <thomas@wytron.com.tw>2015-10-23 07:37:03 +0800
commit88d5ecf4b9c0d5a3bff5d6d98ab7383a550a57db (patch)
tree599e4aee08402b27726c8ae80c86a90d44d8220a /doc
parentd21275ef5e7fe67c592896d6dbb157e219ec0450 (diff)
nios2 : convert altera_pio to driver model
Convert altera_pio to driver model. Signed-off-by: Thomas Chou <thomas@wytron.com.tw> Acked-by: Chin Liang See <clsee@altera.com> Reviewed-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'doc')
-rw-r--r--doc/device-tree-bindings/gpio/altera_pio.txt28
1 files changed, 28 insertions, 0 deletions
diff --git a/doc/device-tree-bindings/gpio/altera_pio.txt b/doc/device-tree-bindings/gpio/altera_pio.txt
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+++ b/doc/device-tree-bindings/gpio/altera_pio.txt
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+Altera GPIO controller bindings
+
+Required properties:
+- compatible:
+ - "altr,pio-1.0"
+- reg: Physical base address and length of the controller's registers.
+
+Optional properties:
+- altr,gpio-bank-width: Width of the GPIO bank. This defines how many pins the
+ GPIO device has. Ranges between 1-32. Optional and defaults to 32 if not
+ specified.
+- gpio-bank-name: bank name attached to this device.
+
+Example:
+
+user_led_pio_8out: gpio@0x4cc0 {
+ compatible = "altr,pio-1.0";
+ reg = <0x00004cc0 0x00000010>;
+ resetvalue = <255>;
+ altr,gpio-bank-width = <8>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ gpio-bank-name = "led";
+};
+
+In this example, the gpio can be accessed as led[0..7] using gpio command of
+u-boot.
+==> gpio clear led0