summaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-w90x900/clksel.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-w90x900/clksel.c')
-rw-r--r--arch/arm/mach-w90x900/clksel.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/arch/arm/mach-w90x900/clksel.c b/arch/arm/mach-w90x900/clksel.c
new file mode 100644
index 0000000..3de4a52
--- /dev/null
+++ b/arch/arm/mach-w90x900/clksel.c
@@ -0,0 +1,91 @@
+/*
+ * linux/arch/arm/mach-w90x900/clksel.c
+ *
+ * Copyright (c) 2008 Nuvoton technology corporation
+ *
+ * Wan ZongShun <mcuos.com@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation;version 2 of the License.
+ */
+
+#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/mutex.h>
+#include <linux/io.h>
+
+#include <mach/hardware.h>
+#include <mach/regs-clock.h>
+
+#define PLL0 0x00
+#define PLL1 0x01
+#define OTHER 0x02
+#define EXT 0x03
+#define MSOFFSET 0x0C
+#define ATAOFFSET 0x0a
+#define LCDOFFSET 0x06
+#define AUDOFFSET 0x04
+#define CPUOFFSET 0x00
+
+static DEFINE_MUTEX(clksel_sem);
+
+static void clock_source_select(const char *dev_id, unsigned int clkval)
+{
+ unsigned int clksel, offset;
+
+ clksel = __raw_readl(REG_CLKSEL);
+
+ if (strcmp(dev_id, "nuc900-ms") == 0)
+ offset = MSOFFSET;
+ else if (strcmp(dev_id, "nuc900-atapi") == 0)
+ offset = ATAOFFSET;
+ else if (strcmp(dev_id, "nuc900-lcd") == 0)
+ offset = LCDOFFSET;
+ else if (strcmp(dev_id, "nuc900-audio") == 0)
+ offset = AUDOFFSET;
+ else
+ offset = CPUOFFSET;
+
+ clksel &= ~(0x03 << offset);
+ clksel |= (clkval << offset);
+
+ __raw_writel(clksel, REG_CLKSEL);
+}
+
+void nuc900_clock_source(struct device *dev, unsigned char *src)
+{
+ unsigned int clkval;
+ const char *dev_id;
+
+ BUG_ON(!src);
+ clkval = 0;
+
+ mutex_lock(&clksel_sem);
+
+ if (dev)
+ dev_id = dev_name(dev);
+ else
+ dev_id = "cpufreq";
+
+ if (strcmp(src, "pll0") == 0)
+ clkval = PLL0;
+ else if (strcmp(src, "pll1") == 0)
+ clkval = PLL1;
+ else if (strcmp(src, "ext") == 0)
+ clkval = EXT;
+ else if (strcmp(src, "oth") == 0)
+ clkval = OTHER;
+
+ clock_source_select(dev_id, clkval);
+
+ mutex_unlock(&clksel_sem);
+}
+EXPORT_SYMBOL(nuc900_clock_source);
+
OpenPOWER on IntegriCloud