drivers/regulator/dbx500-prcmu.c

   1 /*
   2  * Copyright (C) ST-Ericsson SA 2010
   3  *
   4  * License Terms: GNU General Public License v2
   5  * Authors: Sundar Iyer <sundar.iyer@stericsson.com> for ST-Ericsson
   6  *          Bengt Jonsson <bengt.g.jonsson@stericsson.com> for ST-Ericsson
   7  *
   8  * UX500 common part of Power domain regulators
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/err.h>
  13 #include <linux/regulator/driver.h>
  14 #include <linux/debugfs.h>
  15 #include <linux/seq_file.h>
  16 #include <linux/slab.h>
  17
  18 #include "dbx500-prcmu.h"
  19
  20 /*
  21  * power state reference count
  22  */
  23 static int power_state_active_cnt; /* will initialize to zero */
  24 static DEFINE_SPINLOCK(power_state_active_lock);
  25
  26 int power_state_active_get(void)
  27 {
  28         unsigned long flags;
  29         int cnt;
  30
  31         spin_lock_irqsave(&power_state_active_lock, flags);
  32         cnt = power_state_active_cnt;
  33         spin_unlock_irqrestore(&power_state_active_lock, flags);
  34
  35         return cnt;
  36 }
  37
  38 void power_state_active_enable(void)
  39 {
  40         unsigned long flags;
  41
  42         spin_lock_irqsave(&power_state_active_lock, flags);
  43         power_state_active_cnt++;
  44         spin_unlock_irqrestore(&power_state_active_lock, flags);
  45 }
  46
  47 int power_state_active_disable(void)
  48 {
  49         int ret = 0;
  50         unsigned long flags;
  51
  52         spin_lock_irqsave(&power_state_active_lock, flags);
  53         if (power_state_active_cnt <= 0) {
  54                 pr_err("power state: unbalanced enable/disable calls\n");
  55                 ret = -EINVAL;
  56                 goto out;
  57         }
  58
  59         power_state_active_cnt--;
  60 out:
  61         spin_unlock_irqrestore(&power_state_active_lock, flags);
  62         return ret;
  63 }
  64
  65 #ifdef CONFIG_REGULATOR_DEBUG
  66
  67 static struct ux500_regulator_debug {
  68         struct dentry *dir;
  69         struct dentry *status_file;
  70         struct dentry *power_state_cnt_file;
  71         struct dbx500_regulator_info *regulator_array;
  72         int num_regulators;
  73         u8 *state_before_suspend;
  74         u8 *state_after_suspend;
  75 } rdebug;
  76
  77 void ux500_regulator_suspend_debug(void)
  78 {
  79         int i;
  80         for (i = 0; i < rdebug.num_regulators; i++)
  81                 rdebug.state_before_suspend[i] =
  82                         rdebug.regulator_array[i].is_enabled;
  83 }
  84
  85 void ux500_regulator_resume_debug(void)
  86 {
  87         int i;
  88         for (i = 0; i < rdebug.num_regulators; i++)
  89                 rdebug.state_after_suspend[i] =
  90                         rdebug.regulator_array[i].is_enabled;
  91 }
  92
  93 static int ux500_regulator_power_state_cnt_print(struct seq_file *s, void *p)
  94 {
  95         struct device *dev = s->private;
  96         int err;
  97
  98         /* print power state count */
  99         err = seq_printf(s, "ux500-regulator power state count: %i\n",
 100                 power_state_active_get());
 101         if (err < 0)
 102                 dev_err(dev, "seq_printf overflow\n");
 103
 104         return 0;
 105 }
 106
 107 static int ux500_regulator_power_state_cnt_open(struct inode *inode,
 108         struct file *file)
 109 {
 110         return single_open(file, ux500_regulator_power_state_cnt_print,
 111                 inode->i_private);
 112 }
 113
 114 static const struct file_operations ux500_regulator_power_state_cnt_fops = {
 115         .open = ux500_regulator_power_state_cnt_open,
 116         .read = seq_read,
 117         .llseek = seq_lseek,
 118         .release = single_release,
 119         .owner = THIS_MODULE,
 120 };
 121
 122 static int ux500_regulator_status_print(struct seq_file *s, void *p)
 123 {
 124         struct device *dev = s->private;
 125         int err;
 126         int i;
 127
 128         /* print dump header */
 129         err = seq_printf(s, "ux500-regulator status:\n");
 130         if (err < 0)
 131                 dev_err(dev, "seq_printf overflow\n");
 132
 133         err = seq_printf(s, "%31s : %8s : %8s\n", "current",
 134                 "before", "after");
 135         if (err < 0)
 136                 dev_err(dev, "seq_printf overflow\n");
 137
 138         for (i = 0; i < rdebug.num_regulators; i++) {
 139                 struct dbx500_regulator_info *info;
 140                 /* Access per-regulator data */
 141                 info = &rdebug.regulator_array[i];
 142
 143                 /* print status */
 144                 err = seq_printf(s, "%20s : %8s : %8s : %8s\n", info->desc.name,
 145                         info->is_enabled ? "enabled" : "disabled",
 146                         rdebug.state_before_suspend[i] ? "enabled" : "disabled",
 147                         rdebug.state_after_suspend[i] ? "enabled" : "disabled");
 148                 if (err < 0)
 149                         dev_err(dev, "seq_printf overflow\n");
 150         }
 151
 152         return 0;
 153 }
 154
 155 static int ux500_regulator_status_open(struct inode *inode, struct file *file)
 156 {
 157         return single_open(file, ux500_regulator_status_print,
 158                 inode->i_private);
 159 }
 160
 161 static const struct file_operations ux500_regulator_status_fops = {
 162         .open = ux500_regulator_status_open,
 163         .read = seq_read,
 164         .llseek = seq_lseek,
 165         .release = single_release,
 166         .owner = THIS_MODULE,
 167 };
 168
 169 int __attribute__((weak)) dbx500_regulator_testcase(
 170         struct dbx500_regulator_info *regulator_info,
 171         int num_regulators)
 172 {
 173         return 0;
 174 }
 175
 176 int
 177 ux500_regulator_debug_init(struct platform_device *pdev,
 178         struct dbx500_regulator_info *regulator_info,
 179         int num_regulators)
 180 {
 181         /* create directory */
 182         rdebug.dir = debugfs_create_dir("ux500-regulator", NULL);
 183         if (!rdebug.dir)
 184                 goto exit_no_debugfs;
 185
 186         /* create "status" file */
 187         rdebug.status_file = debugfs_create_file("status",
 188                 S_IRUGO, rdebug.dir, &pdev->dev,
 189                 &ux500_regulator_status_fops);
 190         if (!rdebug.status_file)
 191                 goto exit_destroy_dir;
 192
 193         /* create "power-state-count" file */
 194         rdebug.power_state_cnt_file = debugfs_create_file("power-state-count",
 195                 S_IRUGO, rdebug.dir, &pdev->dev,
 196                 &ux500_regulator_power_state_cnt_fops);
 197         if (!rdebug.power_state_cnt_file)
 198                 goto exit_destroy_status;
 199
 200         rdebug.regulator_array = regulator_info;
 201         rdebug.num_regulators = num_regulators;
 202
 203         rdebug.state_before_suspend = kzalloc(num_regulators, GFP_KERNEL);
 204         if (!rdebug.state_before_suspend) {
 205                 dev_err(&pdev->dev,
 206                         "could not allocate memory for saving state\n");
 207                 goto exit_destroy_power_state;
 208         }
 209
 210         rdebug.state_after_suspend = kzalloc(num_regulators, GFP_KERNEL);
 211         if (!rdebug.state_after_suspend) {
 212                 dev_err(&pdev->dev,
 213                         "could not allocate memory for saving state\n");
 214                 goto exit_free;
 215         }
 216
 217         dbx500_regulator_testcase(regulator_info, num_regulators);
 218         return 0;
 219
 220 exit_free:
 221         kfree(rdebug.state_before_suspend);
 222 exit_destroy_power_state:
 223         debugfs_remove(rdebug.power_state_cnt_file);
 224 exit_destroy_status:
 225         debugfs_remove(rdebug.status_file);
 226 exit_destroy_dir:
 227         debugfs_remove(rdebug.dir);
 228 exit_no_debugfs:
 229         dev_err(&pdev->dev, "failed to create debugfs entries.\n");
 230         return -ENOMEM;
 231 }
 232
 233 int ux500_regulator_debug_exit(void)
 234 {
 235         debugfs_remove_recursive(rdebug.dir);
 236         kfree(rdebug.state_after_suspend);
 237         kfree(rdebug.state_before_suspend);
 238
 239         return 0;
 240 }
 241 #endif