/*
   * 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-ac97") == 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);