ae45b1c6 |
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 | |
37 | static DEFINE_MUTEX(clksel_sem); |
38 | |
39 | static 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, "w90p910-ms") == 0) |
46 | offset = MSOFFSET; |
47 | else if (strcmp(dev_id, "w90p910-atapi") == 0) |
48 | offset = ATAOFFSET; |
49 | else if (strcmp(dev_id, "w90p910-lcd") == 0) |
50 | offset = LCDOFFSET; |
51 | else if (strcmp(dev_id, "w90p910-audio") == 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 | |
62 | void w90p910_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 | } |
90 | EXPORT_SYMBOL(w90p910_clock_source); |
91 | |