From 97d654f8eb4b8fbb6e1afef076429a4235a3a3ad Mon Sep 17 00:00:00 2001
From: Russell King <rmk@dyn-67.arm.linux.org.uk>
Date: Wed, 15 Mar 2006 15:54:37 +0000
Subject: [ARM] Convert SA1111 to use clock architecture

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
 arch/arm/mach-sa1100/clock.c | 132 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 132 insertions(+)
 create mode 100644 arch/arm/mach-sa1100/clock.c

(limited to 'arch/arm/mach-sa1100/clock.c')

diff --git a/arch/arm/mach-sa1100/clock.c b/arch/arm/mach-sa1100/clock.c
new file mode 100644
index 00000000000..b1e8fd766c1
--- /dev/null
+++ b/arch/arm/mach-sa1100/clock.c
@@ -0,0 +1,132 @@
+/*
+ *  linux/arch/arm/mach-sa1100/clock.c
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/clk.h>
+#include <linux/spinlock.h>
+
+#include <asm/hardware.h>
+#include <asm/semaphore.h>
+
+struct clk {
+	struct list_head	node;
+	unsigned long		rate;
+	struct module		*owner;
+	const char		*name;
+	unsigned int		enabled;
+	void			(*enable)(void);
+	void			(*disable)(void);
+};
+
+static LIST_HEAD(clocks);
+static DECLARE_MUTEX(clocks_sem);
+static DEFINE_SPINLOCK(clocks_lock);
+
+struct clk *clk_get(struct device *dev, const char *id)
+{
+	struct clk *p, *clk = ERR_PTR(-ENOENT);
+
+	down(&clocks_sem);
+	list_for_each_entry(p, &clocks, node) {
+		if (strcmp(id, p->name) == 0 && try_module_get(p->owner)) {
+			clk = p;
+			break;
+		}
+	}
+	up(&clocks_sem);
+
+	return clk;
+}
+EXPORT_SYMBOL(clk_get);
+
+void clk_put(struct clk *clk)
+{
+	module_put(clk->owner);
+}
+EXPORT_SYMBOL(clk_put);
+
+int clk_enable(struct clk *clk)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	if (clk->enabled++ == 0)
+		clk->enable();
+	spin_unlock_irqrestore(&clocks_lock, flags);
+	return 0;
+}
+EXPORT_SYMBOL(clk_enable);
+
+void clk_disable(struct clk *clk)
+{
+	unsigned long flags;
+
+	WARN_ON(clk->enabled == 0);
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	if (--clk->enabled == 0)
+		clk->disable();
+	spin_unlock_irqrestore(&clocks_lock, flags);
+}
+EXPORT_SYMBOL(clk_disable);
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+	return clk->rate;
+}
+EXPORT_SYMBOL(clk_get_rate);
+
+
+static void clk_gpio27_enable(void)
+{
+	/*
+	 * First, set up the 3.6864MHz clock on GPIO 27 for the SA-1111:
+	 * (SA-1110 Developer's Manual, section 9.1.2.1)
+	 */
+	GAFR |= GPIO_32_768kHz;
+	GPDR |= GPIO_32_768kHz;
+	TUCR = TUCR_3_6864MHz;
+}
+
+static void clk_gpio27_disable(void)
+{
+	TUCR = 0;
+	GPDR &= ~GPIO_32_768kHz;
+	GAFR &= ~GPIO_32_768kHz;
+}
+
+static struct clk clk_gpio27 = {
+	.name		= "GPIO27_CLK",
+	.rate		= 3686400,
+	.enable		= clk_gpio27_enable,
+	.disable	= clk_gpio27_disable,
+};
+
+int clk_register(struct clk *clk)
+{
+	down(&clocks_sem);
+	list_add(&clk->node, &clocks);
+	up(&clocks_sem);
+	return 0;
+}
+EXPORT_SYMBOL(clk_register);
+
+void clk_unregister(struct clk *clk)
+{
+	down(&clocks_sem);
+	list_del(&clk->node);
+	up(&clocks_sem);
+}
+EXPORT_SYMBOL(clk_unregister);
+
+static int __init clk_init(void)
+{
+	clk_register(&clk_gpio27);
+	return 0;
+}
+arch_initcall(clk_init);
-- 
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