[PATCH 1/5] dt: bindings: add means to control flags of specific clocks

kernel at martin.sperl.org kernel at martin.sperl.org
Thu May 5 08:53:24 PDT 2016


From: Martin Sperl <kernel at martin.sperl.org>

Add documentation for "brcm,clock-index" and "brcm,clock-flags"
which allows to set flags to enable the use of parent clocks
that may be different from the default.

In the future this may also contain flags that would allow
enabling higher order mash dividers.

Signed-off-by: Martin Sperl <kernel at martin.sperl.org>
---
 .../devicetree/bindings/clock/brcm,bcm2835-cprman.txt      | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/Documentation/devicetree/bindings/clock/brcm,bcm2835-cprman.txt b/Documentation/devicetree/bindings/clock/brcm,bcm2835-cprman.txt
index e56a1df..cbcca56 100644
--- a/Documentation/devicetree/bindings/clock/brcm,bcm2835-cprman.txt
+++ b/Documentation/devicetree/bindings/clock/brcm,bcm2835-cprman.txt
@@ -18,6 +18,15 @@ Required properties:
 - reg:		Specifies base physical address and size of the registers
 - clocks:	The external oscillator clock phandle

+Optional properties:
+- brcm,clock-index: clock id to which the corresponding brcm,clock-flags
+		      value applies
+- brcm,clock-flags: flags for the specific clock id given in
+		      brcm,clock-index - the bits are defined in
+		      include/dt-bindings/clock/bcm2835.h
+		      of which the bottom 16 bits are reserved for
+		      parent clock selection.
+
 Example:

 	clk_osc: clock at 3 {
@@ -33,7 +42,11 @@ Example:
 		#clock-cells = <1>;
 		reg = <0x7e101000 0x2000>;
 		clocks = <&clk_osc>;
+		/* the pcm clock should use the non-standard pllc-per parent */
+		brcm,clock-index = <BCM2835_CLOCK_PCM>;
+		brcm,clock-flags = <((1 <<BCM2835_PER_PARENT_GND)|
+				     (1 <<BCM2835_PER_PARENT_OSC)|
+				     (1 <<BCM2835_PER_PARENT_PLLC))>;
 	};

 	i2c0: i2c at 7e205000 {
--
2.1.4



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