From 849369d6c66d3054688672f97d31fceb8e8230fb Mon Sep 17 00:00:00 2001
From: root <root@artemis.panaceas.org>
Date: Fri, 25 Dec 2015 04:40:36 +0000
Subject: initial_commit

---
 arch/arm/mach-sa1100/clock.c | 88 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 88 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 00000000..dab3c634
--- /dev/null
+++ b/arch/arm/mach-sa1100/clock.c
@@ -0,0 +1,88 @@
+/*
+ *  linux/arch/arm/mach-sa1100/clock.c
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/device.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 <linux/mutex.h>
+
+#include <mach/hardware.h>
+
+/*
+ * Very simple clock implementation - we only have one clock to deal with.
+ */
+struct clk {
+	unsigned int		enabled;
+};
+
+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;
+
+static DEFINE_SPINLOCK(clocks_lock);
+
+struct clk *clk_get(struct device *dev, const char *id)
+{
+	const char *devname = dev_name(dev);
+
+	return strcmp(devname, "sa1111.0") ? ERR_PTR(-ENOENT) : &clk_gpio27;
+}
+EXPORT_SYMBOL(clk_get);
+
+void clk_put(struct clk *clk)
+{
+}
+EXPORT_SYMBOL(clk_put);
+
+int clk_enable(struct clk *clk)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&clocks_lock, flags);
+	if (clk->enabled++ == 0)
+		clk_gpio27_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_gpio27_disable();
+	spin_unlock_irqrestore(&clocks_lock, flags);
+}
+EXPORT_SYMBOL(clk_disable);
+
+unsigned long clk_get_rate(struct clk *clk)
+{
+	return 3686400;
+}
+EXPORT_SYMBOL(clk_get_rate);
-- 
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