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-rw-r--r--Documentation/devicetree/bindings/net/can/fsl-flexcan.txt63
1 files changed, 13 insertions, 50 deletions
diff --git a/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt b/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt
index 1a729f08986..1ad80d5865a 100644
--- a/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt
+++ b/Documentation/devicetree/bindings/net/can/fsl-flexcan.txt
@@ -1,61 +1,24 @@
-CAN Device Tree Bindings
-------------------------
-2011 Freescale Semiconductor, Inc.
+Flexcan CAN contoller on Freescale's ARM and PowerPC system-on-a-chip (SOC).
-fsl,flexcan-v1.0 nodes
------------------------
-In addition to the required compatible-, reg- and interrupt-properties, you can
-also specify which clock source shall be used for the controller.
+Required properties:
-CPI Clock- Can Protocol Interface Clock
- This CLK_SRC bit of CTRL(control register) selects the clock source to
- the CAN Protocol Interface(CPI) to be either the peripheral clock
- (driven by the PLL) or the crystal oscillator clock. The selected clock
- is the one fed to the prescaler to generate the Serial Clock (Sclock).
- The PRESDIV field of CTRL(control register) controls a prescaler that
- generates the Serial Clock (Sclock), whose period defines the
- time quantum used to compose the CAN waveform.
+- compatible : Should be "fsl,<processor>-flexcan"
-Can Engine Clock Source
- There are two sources for CAN clock
- - Platform Clock It represents the bus clock
- - Oscillator Clock
+ An implementation should also claim any of the following compatibles
+ that it is fully backwards compatible with:
- Peripheral Clock (PLL)
- --------------
- |
- --------- -------------
- | |CPI Clock | Prescaler | Sclock
- | |---------------->| (1.. 256) |------------>
- --------- -------------
- | |
- -------------- ---------------------CLK_SRC
- Oscillator Clock
+ - fsl,p1010-flexcan
-- fsl,flexcan-clock-source : CAN Engine Clock Source.This property selects
- the peripheral clock. PLL clock is fed to the
- prescaler to generate the Serial Clock (Sclock).
- Valid values are "oscillator" and "platform"
- "oscillator": CAN engine clock source is oscillator clock.
- "platform" The CAN engine clock source is the bus clock
- (platform clock).
+- reg : Offset and length of the register set for this device
+- interrupts : Interrupt tuple for this device
+- clock-frequency : The oscillator frequency driving the flexcan device
-- fsl,flexcan-clock-divider : for the reference and system clock, an additional
- clock divider can be specified.
-- clock-frequency: frequency required to calculate the bitrate for FlexCAN.
+Example:
-Note:
- - v1.0 of flexcan-v1.0 represent the IP block version for P1010 SOC.
- - P1010 does not have oscillator as the Clock Source.So the default
- Clock Source is platform clock.
-Examples:
-
- can0@1c000 {
- compatible = "fsl,flexcan-v1.0";
+ can@1c000 {
+ compatible = "fsl,p1010-flexcan";
reg = <0x1c000 0x1000>;
interrupts = <48 0x2>;
interrupt-parent = <&mpic>;
- fsl,flexcan-clock-source = "platform";
- fsl,flexcan-clock-divider = <2>;
- clock-frequency = <fixed by u-boot>;
+ clock-frequency = <200000000>; // filled in by bootloader
};