Hi,
Le mer. 3 janv. 2018 à 22:08, Rob Herring <robh@xxxxxxxxxx> a écrit :
On Mon, Jan 01, 2018 at 03:33:43PM +0100, Paul Cercueil wrote:
This driver will use the TCU (Timer Counter Unit) present on the
Ingenic
JZ47xx SoCs to provide the kernel with a clocksource and timers.
Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
---
.../devicetree/bindings/timer/ingenic,tcu.txt | 35 +++
Separate patch please.
OK.
drivers/clocksource/Kconfig | 8 +
drivers/clocksource/Makefile | 1 +
drivers/clocksource/timer-ingenic.c | 256
+++++++++++++++++++++
4 files changed, 300 insertions(+)
create mode 100644
Documentation/devicetree/bindings/timer/ingenic,tcu.txt
create mode 100644 drivers/clocksource/timer-ingenic.c
v2: Use SPDX identifier for the license
diff --git
a/Documentation/devicetree/bindings/timer/ingenic,tcu.txt
b/Documentation/devicetree/bindings/timer/ingenic,tcu.txt
new file mode 100644
index 000000000000..e4944972ea53
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/ingenic,tcu.txt
@@ -0,0 +1,35 @@
+Ingenic JZ47xx SoCs Timer/Counter Unit driver
+---------------------------------------------
+
+Required properties:
+
+- compatible : should be "ingenic,<socname>-tcu". Valid strings
are:
+ * ingenic,jz4740-tcu
+ * ingenic,jz4770-tcu
+ * ingenic,jz4780-tcu
+- interrupt-parent : phandle of the TCU interrupt controller.
+- interrupts : Specifies the interrupts the controller is
connected to.
+- clocks : List of phandle & clock specifiers for the TCU clocks.
+- clock-names : List of name strings for the TCU clocks.
+- ingenic,channels: a list of TCU channels to be used as timers.
Why is this needed? This looks like you are trying to assign certain
timers to clocksource and clockevent. A common problem, but one that
should be decided by describing h/w features. There must be some
property present or missing to make you decide to use a given channel
or
not.
Well, it's not easy; some TCU channels will be used as PWM, and there's
no way
to know that when the clocksource driver probes. And which ones are PWM
/ which
ones are not, is board-specific. If you have a better solution though,
I take it.
+
+Example:
+
+/ {
+ regmap {
+ compatible = "simple-mfd", "syscon";
+ reg = <0x10002000 0x1000>;
+
+ tcu: timer {
+ compatible = "ingenic,jz4740-tcu";
+
+ clocks = <&tcu 0>, <&tcu 1>;
+ clock-names = "timer0", "timer1";
It's curious that you have timer0 and timer1 here and then channels 0
and 1 below. Would your clocks change if you use channel 2 for
example?
The binding should be a list of clock connections in the h/w, not
just what the driver needs or what the used h/w configuration is.
Rob
I only put these to simplify the example, but you're right, I should
have
all the timer clocks supplied there.
Thanks,
-Paul
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
