diff options
Diffstat (limited to 'arch/arm/mach-w90x900/clksel.c')
-rw-r--r-- | arch/arm/mach-w90x900/clksel.c | 91 |
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 00000000..3de4a521 --- /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); + |