dt-bindings: can: flexcan: add PE clock source property to device tree

The FlexCAN controller can parse clock source property from DTS file to
select PE clock source.

Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt b/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt
index bc77477..a041686 100644 (file)
--- a/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt
+++ b/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt
@@ -32,6 +32,13 @@ Optional properties:
                 ack_gpr is the gpr register offset of CAN stop acknowledge.
                 ack_bit is the bit offset of CAN stop acknowledge.
 
+- fsl,clk-source: Select the clock source to the CAN Protocol Engine (PE).
+                 It's SoC Implementation dependent. Refer to RM for detailed
+                 definition. If this property is not set in device tree node
+                 then driver selects clock source 1 by default.
+                 0: clock source 0 (oscillator clock)
+                 1: clock source 1 (peripheral clock)
+
 Example:
 
        can@1c000 {
@@ -40,4 +47,5 @@ Example:
                interrupts = <48 0x2>;
                interrupt-parent = <&mpic>;
                clock-frequency = <200000000>; // filled in by bootloader
+               fsl,clk-source = <0>; // select clock source 0 for PE
        };