1/*
2 * linux/arch/arm/mach-w90x900/clksel.c
3 *
4 * Copyright (c) 2008 Nuvoton technology corporation
5 *
6 * Wan ZongShun <mcuos.com@gmail.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation;version 2 of the License.
11 */
12
13#include <linux/module.h>
14#include <linux/kernel.h>
15#include <linux/device.h>
16#include <linux/list.h>
17#include <linux/errno.h>
18#include <linux/err.h>
19#include <linux/string.h>
20#include <linux/clk.h>
21#include <linux/mutex.h>
22#include <linux/io.h>
23
24#include <mach/hardware.h>
25#include <mach/regs-clock.h>
26
27#define PLL0		0x00
28#define PLL1		0x01
29#define OTHER		0x02
30#define EXT		0x03
31#define MSOFFSET	0x0C
32#define ATAOFFSET	0x0a
33#define LCDOFFSET	0x06
34#define AUDOFFSET	0x04
35#define CPUOFFSET	0x00
36
37static DEFINE_MUTEX(clksel_sem);
38
39static void clock_source_select(const char *dev_id, unsigned int clkval)
40{
41	unsigned int clksel, offset;
42
43	clksel = __raw_readl(REG_CLKSEL);
44
45	if (strcmp(dev_id, "nuc900-ms") == 0)
46		offset = MSOFFSET;
47	else if (strcmp(dev_id, "nuc900-atapi") == 0)
48		offset = ATAOFFSET;
49	else if (strcmp(dev_id, "nuc900-lcd") == 0)
50		offset = LCDOFFSET;
51	else if (strcmp(dev_id, "nuc900-ac97") == 0)
52		offset = AUDOFFSET;
53	else
54		offset = CPUOFFSET;
55
56	clksel &= ~(0x03 << offset);
57	clksel |= (clkval << offset);
58
59	__raw_writel(clksel, REG_CLKSEL);
60}
61
62void nuc900_clock_source(struct device *dev, unsigned char *src)
63{
64	unsigned int clkval;
65	const char *dev_id;
66
67	BUG_ON(!src);
68	clkval = 0;
69
70	mutex_lock(&clksel_sem);
71
72	if (dev)
73		dev_id = dev_name(dev);
74	else
75		dev_id = "cpufreq";
76
77	if (strcmp(src, "pll0") == 0)
78		clkval = PLL0;
79	else if (strcmp(src, "pll1") == 0)
80		clkval = PLL1;
81	else if (strcmp(src, "ext") == 0)
82		clkval = EXT;
83	else if (strcmp(src, "oth") == 0)
84		clkval = OTHER;
85
86	clock_source_select(dev_id, clkval);
87
88	mutex_unlock(&clksel_sem);
89}
90EXPORT_SYMBOL(nuc900_clock_source);
91
92