clk: add accuracy support for fixed clock

This patch adds support for accuracy retrieval on fixed clocks.
It also adds a new dt property called 'clock-accuracy' to define the clock
accuracy.

This can be usefull for oscillator (RC, crystal, ...) definitions which are
always given an accuracy characteristic.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/clock/fixed-clock.txt b/Documentation/devicetree/bindings/clock/fixed-clock.txt
index 0b1fe7824093..48ea0ad8ad46 100644
--- a/Documentation/devicetree/bindings/clock/fixed-clock.txt
+++ b/Documentation/devicetree/bindings/clock/fixed-clock.txt
@@ -10,6 +10,8 @@ Required properties:
 - clock-frequency : frequency of clock in Hz. Should be a single cell.
 
 Optional properties:
+- clock-accuracy : accuracy of clock in ppb (parts per billion).
+		   Should be a single cell.
 - gpios : From common gpio binding; gpio connection to clock enable pin.
 - clock-output-names : From common clock binding.
 
@@ -18,4 +20,5 @@ Example:
 		compatible = "fixed-clock";
 		#clock-cells = <0>;
 		clock-frequency = <1000000000>;
+		clock-accuracy = <100>;
 	};