clk: at91: add slow clk documentation

Add slow clk, and slow oscillators documentation.

Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
This commit is contained in:
Boris BREZILLON 2014-04-22 15:12:33 +02:00 committed by Nicolas Ferre
parent 80eded6ce8
commit 4d735e548c

View file

@ -6,6 +6,16 @@ This binding uses the common clock binding[1].
Required properties:
- compatible : shall be one of the following:
"atmel,at91sam9x5-sckc":
at91 SCKC (Slow Clock Controller)
This node contains the slow clock definitions.
"atmel,at91sam9x5-clk-slow-osc":
at91 slow oscillator
"atmel,at91sam9x5-clk-slow-rc-osc":
at91 internal slow RC oscillator
"atmel,at91rm9200-pmc" or
"atmel,at91sam9g45-pmc" or
"atmel,at91sam9n12-pmc" or
@ -15,6 +25,11 @@ Required properties:
All at91 specific clocks (clocks defined below) must be child
node of the PMC node.
"atmel,at91sam9x5-clk-slow" (under sckc node)
or
"atmel,at91sam9260-clk-slow" (under pmc node):
at91 slow clk
"atmel,at91rm9200-clk-main-osc"
"atmel,at91sam9x5-clk-main-rc-osc"
at91 main clk sources
@ -59,6 +74,63 @@ Required properties:
"atmel,at91sam9x5-clk-utmi":
at91 utmi clock
Required properties for SCKC node:
- reg : defines the IO memory reserved for the SCKC.
- #size-cells : shall be 0 (reg is used to encode clk id).
- #address-cells : shall be 1 (reg is used to encode clk id).
For example:
sckc: sckc@fffffe50 {
compatible = "atmel,sama5d3-pmc";
reg = <0xfffffe50 0x4>
#size-cells = <0>;
#address-cells = <1>;
/* put at91 slow clocks here */
};
Required properties for internal slow RC oscillator:
- #clock-cells : from common clock binding; shall be set to 0.
- clock-frequency : define the internal RC oscillator frequency.
Optional properties:
- clock-accuracy : define the internal RC oscillator accuracy.
For example:
slow_rc_osc: slow_rc_osc {
compatible = "atmel,at91sam9x5-clk-slow-rc-osc";
clock-frequency = <32768>;
clock-accuracy = <50000000>;
};
Required properties for slow oscillator:
- #clock-cells : from common clock binding; shall be set to 0.
- clocks : shall encode the main osc source clk sources (see atmel datasheet).
Optional properties:
- atmel,osc-bypass : boolean property. Set this when a clock signal is directly
provided on XIN.
For example:
slow_osc: slow_osc {
compatible = "atmel,at91rm9200-clk-slow-osc";
#clock-cells = <0>;
clocks = <&slow_xtal>;
};
Required properties for slow clock:
- #clock-cells : from common clock binding; shall be set to 0.
- clocks : shall encode the slow clk sources (see atmel datasheet).
For example:
clk32k: slck {
compatible = "atmel,at91sam9x5-clk-slow";
#clock-cells = <0>;
clocks = <&slow_rc_osc &slow_osc>;
};
Required properties for PMC node:
- reg : defines the IO memory reserved for the PMC.
- #size-cells : shall be 0 (reg is used to encode clk id).