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Diffstat (limited to 'arch/arm/mach-sa1100/clock.c')
-rw-r--r--arch/arm/mach-sa1100/clock.c100
1 files changed, 100 insertions, 0 deletions
diff --git a/arch/arm/mach-sa1100/clock.c b/arch/arm/mach-sa1100/clock.c
new file mode 100644
index 00000000..172ebd0e
--- /dev/null
+++ b/arch/arm/mach-sa1100/clock.c
@@ -0,0 +1,100 @@
+/*
+ * 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 <linux/io.h>
+#include <linux/clkdev.h>
+
+#include <mach/hardware.h>
+
+struct clkops {
+ void (*enable)(struct clk *);
+ void (*disable)(struct clk *);
+};
+
+struct clk {
+ const struct clkops *ops;
+ unsigned int enabled;
+};
+
+#define DEFINE_CLK(_name, _ops) \
+struct clk clk_##_name = { \
+ .ops = _ops, \
+ }
+
+static DEFINE_SPINLOCK(clocks_lock);
+
+static void clk_gpio27_enable(struct clk *clk)
+{
+ /*
+ * 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(struct clk *clk)
+{
+ TUCR = 0;
+ GPDR &= ~GPIO_32_768kHz;
+ GAFR &= ~GPIO_32_768kHz;
+}
+
+int clk_enable(struct clk *clk)
+{
+ unsigned long flags;
+
+ if (clk) {
+ spin_lock_irqsave(&clocks_lock, flags);
+ if (clk->enabled++ == 0)
+ clk->ops->enable(clk);
+ spin_unlock_irqrestore(&clocks_lock, flags);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(clk_enable);
+
+void clk_disable(struct clk *clk)
+{
+ unsigned long flags;
+
+ if (clk) {
+ WARN_ON(clk->enabled == 0);
+ spin_lock_irqsave(&clocks_lock, flags);
+ if (--clk->enabled == 0)
+ clk->ops->disable(clk);
+ spin_unlock_irqrestore(&clocks_lock, flags);
+ }
+}
+EXPORT_SYMBOL(clk_disable);
+
+const struct clkops clk_gpio27_ops = {
+ .enable = clk_gpio27_enable,
+ .disable = clk_gpio27_disable,
+};
+
+static DEFINE_CLK(gpio27, &clk_gpio27_ops);
+
+static struct clk_lookup sa11xx_clkregs[] = {
+ CLKDEV_INIT("sa1111.0", NULL, &clk_gpio27),
+ CLKDEV_INIT("sa1100-rtc", NULL, NULL),
+};
+
+static int __init sa11xx_clk_init(void)
+{
+ clkdev_add_table(sa11xx_clkregs, ARRAY_SIZE(sa11xx_clkregs));
+ return 0;
+}
+core_initcall(sa11xx_clk_init);