kernel/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 void power_state_active_enable(void)
  28 {
  29         unsigned long flags;
  30
  31         spin_lock_irqsave(&power_state_active_lock, flags);
  32         power_state_active_cnt++;
  33         spin_unlock_irqrestore(&power_state_active_lock, flags);
  34 }
  35
  36 int power_state_active_disable(void)
  37 {
  38         int ret = 0;
  39         unsigned long flags;
  40
  41         spin_lock_irqsave(&power_state_active_lock, flags);
  42         if (power_state_active_cnt <= 0) {
  43                 pr_err("power state: unbalanced enable/disable calls\n");
  44                 ret = -EINVAL;
  45                 goto out;
  46         }
  47
  48         power_state_active_cnt--;
  49 out:
  50         spin_unlock_irqrestore(&power_state_active_lock, flags);
  51         return ret;
  52 }
  53
  54 #ifdef CONFIG_REGULATOR_DEBUG
  55
  56 static int power_state_active_get(void)
  57 {
  58         unsigned long flags;
  59         int cnt;
  60
  61         spin_lock_irqsave(&power_state_active_lock, flags);
  62         cnt = power_state_active_cnt;
  63         spin_unlock_irqrestore(&power_state_active_lock, flags);
  64
  65         return cnt;
  66 }
  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
  82         for (i = 0; i < rdebug.num_regulators; i++)
  83                 rdebug.state_before_suspend[i] =
  84                         rdebug.regulator_array[i].is_enabled;
  85 }
  86
  87 void ux500_regulator_resume_debug(void)
  88 {
  89         int i;
  90
  91         for (i = 0; i < rdebug.num_regulators; i++)
  92                 rdebug.state_after_suspend[i] =
  93                         rdebug.regulator_array[i].is_enabled;
  94 }
  95
  96 static int ux500_regulator_power_state_cnt_print(struct seq_file *s, void *p)
  97 {
  98         /* print power state count */
  99         seq_printf(s, "ux500-regulator power state count: %i\n",
 100                    power_state_active_get());
 101
 102         return 0;
 103 }
 104
 105 static int ux500_regulator_power_state_cnt_open(struct inode *inode,
 106         struct file *file)
 107 {
 108         return single_open(file, ux500_regulator_power_state_cnt_print,
 109                 inode->i_private);
 110 }
 111
 112 static const struct file_operations ux500_regulator_power_state_cnt_fops = {
 113         .open = ux500_regulator_power_state_cnt_open,
 114         .read = seq_read,
 115         .llseek = seq_lseek,
 116         .release = single_release,
 117         .owner = THIS_MODULE,
 118 };
 119
 120 static int ux500_regulator_status_print(struct seq_file *s, void *p)
 121 {
 122         int i;
 123
 124         /* print dump header */
 125         seq_puts(s, "ux500-regulator status:\n");
 126         seq_printf(s, "%31s : %8s : %8s\n", "current", "before", "after");
 127
 128         for (i = 0; i < rdebug.num_regulators; i++) {
 129                 struct dbx500_regulator_info *info;
 130                 /* Access per-regulator data */
 131                 info = &rdebug.regulator_array[i];
 132
 133                 /* print status */
 134                 seq_printf(s, "%20s : %8s : %8s : %8s\n",
 135                            info->desc.name,
 136                            info->is_enabled ? "enabled" : "disabled",
 137                            rdebug.state_before_suspend[i] ? "enabled" : "disabled",
 138                            rdebug.state_after_suspend[i] ? "enabled" : "disabled");
 139         }
 140
 141         return 0;
 142 }
 143
 144 static int ux500_regulator_status_open(struct inode *inode, struct file *file)
 145 {
 146         return single_open(file, ux500_regulator_status_print,
 147                 inode->i_private);
 148 }
 149
 150 static const struct file_operations ux500_regulator_status_fops = {
 151         .open = ux500_regulator_status_open,
 152         .read = seq_read,
 153         .llseek = seq_lseek,
 154         .release = single_release,
 155         .owner = THIS_MODULE,
 156 };
 157
 158 int __attribute__((weak)) dbx500_regulator_testcase(
 159         struct dbx500_regulator_info *regulator_info,
 160         int num_regulators)
 161 {
 162         return 0;
 163 }
 164
 165 int
 166 ux500_regulator_debug_init(struct platform_device *pdev,
 167         struct dbx500_regulator_info *regulator_info,
 168         int num_regulators)
 169 {
 170         /* create directory */
 171         rdebug.dir = debugfs_create_dir("ux500-regulator", NULL);
 172         if (!rdebug.dir)
 173                 goto exit_no_debugfs;
 174
 175         /* create "status" file */
 176         rdebug.status_file = debugfs_create_file("status",
 177                 S_IRUGO, rdebug.dir, &pdev->dev,
 178                 &ux500_regulator_status_fops);
 179         if (!rdebug.status_file)
 180                 goto exit_destroy_dir;
 181
 182         /* create "power-state-count" file */
 183         rdebug.power_state_cnt_file = debugfs_create_file("power-state-count",
 184                 S_IRUGO, rdebug.dir, &pdev->dev,
 185                 &ux500_regulator_power_state_cnt_fops);
 186         if (!rdebug.power_state_cnt_file)
 187                 goto exit_destroy_status;
 188
 189         rdebug.regulator_array = regulator_info;
 190         rdebug.num_regulators = num_regulators;
 191
 192         rdebug.state_before_suspend = kzalloc(num_regulators, GFP_KERNEL);
 193         if (!rdebug.state_before_suspend)
 194                 goto exit_destroy_power_state;
 195
 196         rdebug.state_after_suspend = kzalloc(num_regulators, GFP_KERNEL);
 197         if (!rdebug.state_after_suspend)
 198                 goto exit_free;
 199
 200         dbx500_regulator_testcase(regulator_info, num_regulators);
 201         return 0;
 202
 203 exit_free:
 204         kfree(rdebug.state_before_suspend);
 205 exit_destroy_power_state:
 206         debugfs_remove(rdebug.power_state_cnt_file);
 207 exit_destroy_status:
 208         debugfs_remove(rdebug.status_file);
 209 exit_destroy_dir:
 210         debugfs_remove(rdebug.dir);
 211 exit_no_debugfs:
 212         dev_err(&pdev->dev, "failed to create debugfs entries.\n");
 213         return -ENOMEM;
 214 }
 215
 216 int ux500_regulator_debug_exit(void)
 217 {
 218         debugfs_remove_recursive(rdebug.dir);
 219         kfree(rdebug.state_after_suspend);
 220         kfree(rdebug.state_before_suspend);
 221
 222         return 0;
 223 }
 224 #endif