openwrt/target/linux/sunxi/patches-3.14/176-clk-sun5i-add-support-for-reset-ctrler.patch

From 3ec31fa2ce161d35f787354037f94d9d22d825d1 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime.ripard@free-electrons.com>
Date: Fri, 20 Dec 2013 22:41:08 +0100
Subject: [PATCH] clocksource: sun5i: Add support for reset controller

The Allwinner A31 that uses this timer has the timer IP asserted in reset.
Add an optional reset property to the DT, and deassert the timer from reset if
it's there.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
---
 .../devicetree/bindings/timer/allwinner,sun5i-a13-hstimer.txt       | 4 ++++
 drivers/clocksource/timer-sun5i.c                                   | 6 ++++++
 2 files changed, 10 insertions(+)

--- a/Documentation/devicetree/bindings/timer/allwinner,sun5i-a13-hstimer.txt
+++ b/Documentation/devicetree/bindings/timer/allwinner,sun5i-a13-hstimer.txt
@@ -9,6 +9,9 @@ Required properties:
 		one)
 - clocks: phandle to the source clock (usually the AHB clock)
 
+Optionnal properties:
+- resets: phandle to a reset controller asserting the timer
+
 Example:
 
 timer@01c60000 {
@@ -19,4 +22,5 @@ timer@01c60000 {
 		     <0 53 1>,
 		     <0 54 1>;
 	clocks = <&ahb1_gates 19>;
+	resets = <&ahb1rst 19>;
 };
--- a/drivers/clocksource/timer-sun5i.c
+++ b/drivers/clocksource/timer-sun5i.c
@@ -16,6 +16,7 @@
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/irqreturn.h>
+#include <linux/reset.h>
 #include <linux/sched_clock.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
@@ -143,6 +144,7 @@ static u64 sun5i_timer_sched_read(void)
 
 static void __init sun5i_timer_init(struct device_node *node)
 {
+	struct reset_control *rstc;
 	unsigned long rate;
 	struct clk *clk;
 	int ret, irq;
@@ -162,6 +164,10 @@ static void __init sun5i_timer_init(stru
 	clk_prepare_enable(clk);
 	rate = clk_get_rate(clk);
 
+	rstc = of_reset_control_get(node, NULL);
+	if (!IS_ERR(rstc))
+		reset_control_deassert(rstc);
+
 	writel(~0, timer_base + TIMER_INTVAL_LO_REG(1));
 	writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
 	       timer_base + TIMER_CTL_REG(1));