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 #if defined(CONFIG_ARCH_OMAP24XX) || defined(CONFIG_ARCH_OMAP34XX)
  34 # include "../mach-omap2/control.h"
  35 #endif
  36
  37 #ifdef CONFIG_OMAP_MUX
  38
  39 #define OMAP24XX_PULL_ENA       (1 << 3)
  40 #define OMAP24XX_PULL_UP        (1 << 4)
  41
  42 static struct pin_config * pin_table;
  43 static unsigned long pin_table_sz;
  44
  45 extern struct pin_config * omap730_pins;
  46 extern struct pin_config * omap1xxx_pins;
  47 extern struct pin_config * omap24xx_pins;
  48
  49 int __init omap_mux_register(struct pin_config * pins, unsigned long size)
  50 {
  51         pin_table = pins;
  52         pin_table_sz = size;
  53
  54         return 0;
  55 }
  56
  57 /*
  58  * Sets the Omap MUX and PULL_DWN registers based on the table
  59  */
  60 int __init_or_module omap_cfg_reg(const unsigned long index)
  61 {
  62         static DEFINE_SPINLOCK(mux_spin_lock);
  63
  64         unsigned long flags;
  65         struct pin_config *cfg;
  66         unsigned int reg_orig = 0, reg = 0, pu_pd_orig = 0, pu_pd = 0,
  67                 pull_orig = 0, pull = 0;
  68         unsigned int mask, warn = 0;
  69
  70         if (!pin_table)
  71                 BUG();
  72
  73         if (index >= pin_table_sz) {
  74                 printk(KERN_ERR "Invalid pin mux index: %lu (%lu)\n",
  75                        index, pin_table_sz);
  76                 dump_stack();
  77                 return -ENODEV;
  78         }
  79
  80         cfg = (struct pin_config *)&pin_table[index];
  81 #ifdef CONFIG_ARCH_OMAP24XX
  82         /* REVISIT: Convert this code to use ctrl_{read,write}_reg */
  83         if (cpu_is_omap24xx()) {
  84                 u8 reg = 0;
  85
  86                 reg |= cfg->mask & 0x7;
  87                 if (cfg->pull_val)
  88                         reg |= OMAP24XX_PULL_ENA;
  89                 if(cfg->pu_pd_val)
  90                         reg |= OMAP24XX_PULL_UP;
  91 #if defined(CONFIG_OMAP_MUX_DEBUG) || defined(CONFIG_OMAP_MUX_WARNINGS)
  92                 {
  93                         u8 orig = omap_readb(omap2_ctrl_base + cfg->mux_reg);
  94                         u8 debug = 0;
  95
  96 #ifdef  CONFIG_OMAP_MUX_DEBUG
  97                         debug = cfg->debug;
  98 #endif
  99                         warn = (orig != reg);
 100                         if (debug || warn)
 101                                 printk("MUX: setup %s (0x%08lx): 0x%02x -> 0x%02x\n",
 102                                                 cfg->name,
 103                                                 omap2_ctrl_base + cfg->mux_reg,
 104                                                 orig, reg);
 105                 }
 106 #endif
 107                 omap_writeb(reg, omap2_ctrl_base + cfg->mux_reg);
 108
 109                 return 0;
 110         }
 111 #endif /* ARCH_OMAP24XX */
 112
 113         /* Check the mux register in question */
 114         if (cfg->mux_reg) {
 115                 unsigned        tmp1, tmp2;
 116
 117                 spin_lock_irqsave(&mux_spin_lock, flags);
 118                 reg_orig = omap_readl(cfg->mux_reg);
 119
 120                 /* The mux registers always seem to be 3 bits long */
 121                 mask = (0x7 << cfg->mask_offset);
 122                 tmp1 = reg_orig & mask;
 123                 reg = reg_orig & ~mask;
 124
 125                 tmp2 = (cfg->mask << cfg->mask_offset);
 126                 reg |= tmp2;
 127
 128                 if (tmp1 != tmp2)
 129                         warn = 1;
 130
 131                 omap_writel(reg, cfg->mux_reg);
 132                 spin_unlock_irqrestore(&mux_spin_lock, flags);
 133         }
 134
 135         /* Check for pull up or pull down selection on 1610 */
 136         if (!cpu_is_omap15xx()) {
 137                 if (cfg->pu_pd_reg && cfg->pull_val) {
 138                         spin_lock_irqsave(&mux_spin_lock, flags);
 139                         pu_pd_orig = omap_readl(cfg->pu_pd_reg);
 140                         mask = 1 << cfg->pull_bit;
 141
 142                         if (cfg->pu_pd_val) {
 143                                 if (!(pu_pd_orig & mask))
 144                                         warn = 1;
 145                                 /* Use pull up */
 146                                 pu_pd = pu_pd_orig | mask;
 147                         } else {
 148                                 if (pu_pd_orig & mask)
 149                                         warn = 1;
 150                                 /* Use pull down */
 151                                 pu_pd = pu_pd_orig & ~mask;
 152                         }
 153                         omap_writel(pu_pd, cfg->pu_pd_reg);
 154                         spin_unlock_irqrestore(&mux_spin_lock, flags);
 155                 }
 156         }
 157
 158         /* Check for an associated pull down register */
 159         if (cfg->pull_reg) {
 160                 spin_lock_irqsave(&mux_spin_lock, flags);
 161                 pull_orig = omap_readl(cfg->pull_reg);
 162                 mask = 1 << cfg->pull_bit;
 163
 164                 if (cfg->pull_val) {
 165                         if (pull_orig & mask)
 166                                 warn = 1;
 167                         /* Low bit = pull enabled */
 168                         pull = pull_orig & ~mask;
 169                 } else {
 170                         if (!(pull_orig & mask))
 171                                 warn = 1;
 172                         /* High bit = pull disabled */
 173                         pull = pull_orig | mask;
 174                 }
 175
 176                 omap_writel(pull, cfg->pull_reg);
 177                 spin_unlock_irqrestore(&mux_spin_lock, flags);
 178         }
 179
 180         if (warn) {
 181 #ifdef CONFIG_OMAP_MUX_WARNINGS
 182                 printk(KERN_WARNING "MUX: initialized %s\n", cfg->name);
 183 #endif
 184         }
 185
 186 #ifdef CONFIG_OMAP_MUX_DEBUG
 187         if (cfg->debug || warn) {
 188                 printk("MUX: Setting register %s\n", cfg->name);
 189                 printk("      %s (0x%08x) = 0x%08x -> 0x%08x\n",
 190                        cfg->mux_reg_name, cfg->mux_reg, reg_orig, reg);
 191
 192                 if (!cpu_is_omap15xx()) {
 193                         if (cfg->pu_pd_reg && cfg->pull_val) {
 194                                 printk("      %s (0x%08x) = 0x%08x -> 0x%08x\n",
 195                                        cfg->pu_pd_name, cfg->pu_pd_reg,
 196                                        pu_pd_orig, pu_pd);
 197                         }
 198                 }
 199
 200                 if (cfg->pull_reg)
 201                         printk("      %s (0x%08x) = 0x%08x -> 0x%08x\n",
 202                                cfg->pull_name, cfg->pull_reg, pull_orig, pull);
 203         }
 204 #endif
 205
 206 #ifdef CONFIG_OMAP_MUX_ERRORS
 207         return warn ? -ETXTBSY : 0;
 208 #else
 209         return 0;
 210 #endif
 211 }
 212 EXPORT_SYMBOL(omap_cfg_reg);
 213 #else
 214 #define omap_mux_init() do {} while(0)
 215 #define omap_cfg_reg(x) do {} while(0)
 216 #endif  /* CONFIG_OMAP_MUX */