i2c: normal_i2c can be made const (remaining drivers)
[linux-2.6] / arch / arm / plat-omap / mux.c
1 /*
2  * linux/arch/arm/plat-omap/mux.c
3  *
4  * Utility to set the Omap MUX and PULL_DWN registers from a table in mux.h
5  *
6  * Copyright (C) 2003 - 2005 Nokia Corporation
7  *
8  * Written by Tony Lindgren <tony.lindgren@nokia.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23  *
24  */
25 #include <linux/module.h>
26 #include <linux/init.h>
27 #include <linux/kernel.h>
28 #include <asm/system.h>
29 #include <asm/io.h>
30 #include <linux/spinlock.h>
31 #include <asm/arch/mux.h>
32
33 #ifdef CONFIG_OMAP_MUX
34
35 #define OMAP24XX_L4_BASE        0x48000000
36 #define OMAP24XX_PULL_ENA       (1 << 3)
37 #define OMAP24XX_PULL_UP        (1 << 4)
38
39 static struct pin_config * pin_table;
40 static unsigned long pin_table_sz;
41
42 extern struct pin_config * omap730_pins;
43 extern struct pin_config * omap1xxx_pins;
44 extern struct pin_config * omap24xx_pins;
45
46 int __init omap_mux_register(struct pin_config * pins, unsigned long size)
47 {
48         pin_table = pins;
49         pin_table_sz = size;
50
51         return 0;
52 }
53
54 /*
55  * Sets the Omap MUX and PULL_DWN registers based on the table
56  */
57 int __init_or_module omap_cfg_reg(const unsigned long index)
58 {
59         static DEFINE_SPINLOCK(mux_spin_lock);
60
61         unsigned long flags;
62         struct pin_config *cfg;
63         unsigned int reg_orig = 0, reg = 0, pu_pd_orig = 0, pu_pd = 0,
64                 pull_orig = 0, pull = 0;
65         unsigned int mask, warn = 0;
66
67         if (!pin_table)
68                 BUG();
69
70         if (index >= pin_table_sz) {
71                 printk(KERN_ERR "Invalid pin mux index: %lu (%lu)\n",
72                        index, pin_table_sz);
73                 dump_stack();
74                 return -ENODEV;
75         }
76
77         cfg = (struct pin_config *)&pin_table[index];
78         if (cpu_is_omap24xx()) {
79                 u8 reg = 0;
80
81                 reg |= cfg->mask & 0x7;
82                 if (cfg->pull_val)
83                         reg |= OMAP24XX_PULL_ENA;
84                 if(cfg->pu_pd_val)
85                         reg |= OMAP24XX_PULL_UP;
86 #if defined(CONFIG_OMAP_MUX_DEBUG) || defined(CONFIG_OMAP_MUX_WARNINGS)
87                 {
88                         u8 orig = omap_readb(OMAP24XX_L4_BASE + cfg->mux_reg);
89                         u8 debug = 0;
90
91 #ifdef  CONFIG_OMAP_MUX_DEBUG
92                         debug = cfg->debug;
93 #endif
94                         warn = (orig != reg);
95                         if (debug || warn)
96                                 printk("MUX: setup %s (0x%08x): 0x%02x -> 0x%02x\n",
97                                                 cfg->name,
98                                                 OMAP24XX_L4_BASE + cfg->mux_reg,
99                                                 orig, reg);
100                 }
101 #endif
102                 omap_writeb(reg, OMAP24XX_L4_BASE + cfg->mux_reg);
103
104                 return 0;
105         }
106
107         /* Check the mux register in question */
108         if (cfg->mux_reg) {
109                 unsigned        tmp1, tmp2;
110
111                 spin_lock_irqsave(&mux_spin_lock, flags);
112                 reg_orig = omap_readl(cfg->mux_reg);
113
114                 /* The mux registers always seem to be 3 bits long */
115                 mask = (0x7 << cfg->mask_offset);
116                 tmp1 = reg_orig & mask;
117                 reg = reg_orig & ~mask;
118
119                 tmp2 = (cfg->mask << cfg->mask_offset);
120                 reg |= tmp2;
121
122                 if (tmp1 != tmp2)
123                         warn = 1;
124
125                 omap_writel(reg, cfg->mux_reg);
126                 spin_unlock_irqrestore(&mux_spin_lock, flags);
127         }
128
129         /* Check for pull up or pull down selection on 1610 */
130         if (!cpu_is_omap15xx()) {
131                 if (cfg->pu_pd_reg && cfg->pull_val) {
132                         spin_lock_irqsave(&mux_spin_lock, flags);
133                         pu_pd_orig = omap_readl(cfg->pu_pd_reg);
134                         mask = 1 << cfg->pull_bit;
135
136                         if (cfg->pu_pd_val) {
137                                 if (!(pu_pd_orig & mask))
138                                         warn = 1;
139                                 /* Use pull up */
140                                 pu_pd = pu_pd_orig | mask;
141                         } else {
142                                 if (pu_pd_orig & mask)
143                                         warn = 1;
144                                 /* Use pull down */
145                                 pu_pd = pu_pd_orig & ~mask;
146                         }
147                         omap_writel(pu_pd, cfg->pu_pd_reg);
148                         spin_unlock_irqrestore(&mux_spin_lock, flags);
149                 }
150         }
151
152         /* Check for an associated pull down register */
153         if (cfg->pull_reg) {
154                 spin_lock_irqsave(&mux_spin_lock, flags);
155                 pull_orig = omap_readl(cfg->pull_reg);
156                 mask = 1 << cfg->pull_bit;
157
158                 if (cfg->pull_val) {
159                         if (pull_orig & mask)
160                                 warn = 1;
161                         /* Low bit = pull enabled */
162                         pull = pull_orig & ~mask;
163                 } else {
164                         if (!(pull_orig & mask))
165                                 warn = 1;
166                         /* High bit = pull disabled */
167                         pull = pull_orig | mask;
168                 }
169
170                 omap_writel(pull, cfg->pull_reg);
171                 spin_unlock_irqrestore(&mux_spin_lock, flags);
172         }
173
174         if (warn) {
175 #ifdef CONFIG_OMAP_MUX_WARNINGS
176                 printk(KERN_WARNING "MUX: initialized %s\n", cfg->name);
177 #endif
178         }
179
180 #ifdef CONFIG_OMAP_MUX_DEBUG
181         if (cfg->debug || warn) {
182                 printk("MUX: Setting register %s\n", cfg->name);
183                 printk("      %s (0x%08x) = 0x%08x -> 0x%08x\n",
184                        cfg->mux_reg_name, cfg->mux_reg, reg_orig, reg);
185
186                 if (!cpu_is_omap15xx()) {
187                         if (cfg->pu_pd_reg && cfg->pull_val) {
188                                 printk("      %s (0x%08x) = 0x%08x -> 0x%08x\n",
189                                        cfg->pu_pd_name, cfg->pu_pd_reg,
190                                        pu_pd_orig, pu_pd);
191                         }
192                 }
193
194                 if (cfg->pull_reg)
195                         printk("      %s (0x%08x) = 0x%08x -> 0x%08x\n",
196                                cfg->pull_name, cfg->pull_reg, pull_orig, pull);
197         }
198 #endif
199
200 #ifdef CONFIG_OMAP_MUX_ERRORS
201         return warn ? -ETXTBSY : 0;
202 #else
203         return 0;
204 #endif
205 }
206 EXPORT_SYMBOL(omap_cfg_reg);
207 #else
208 #define omap_mux_init() do {} while(0)
209 #define omap_cfg_reg(x) do {} while(0)
210 #endif  /* CONFIG_OMAP_MUX */