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