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 static int ux500_regulator_power_state_cnt_print(struct seq_file *s, void *p)
  79 {
  80         /* print power state count */
  81         seq_printf(s, "ux500-regulator power state count: %i\n",
  82                    power_state_active_get());
  83
  84         return 0;
  85 }
  86
  87 static int ux500_regulator_power_state_cnt_open(struct inode *inode,
  88         struct file *file)
  89 {
  90         return single_open(file, ux500_regulator_power_state_cnt_print,
  91                 inode->i_private);
  92 }
  93
  94 static const struct file_operations ux500_regulator_power_state_cnt_fops = {
  95         .open = ux500_regulator_power_state_cnt_open,
  96         .read = seq_read,
  97         .llseek = seq_lseek,
  98         .release = single_release,
  99         .owner = THIS_MODULE,
 100 };
 101
 102 static int ux500_regulator_status_print(struct seq_file *s, void *p)
 103 {
 104         int i;
 105
 106         /* print dump header */
 107         seq_puts(s, "ux500-regulator status:\n");
 108         seq_printf(s, "%31s : %8s : %8s\n", "current", "before", "after");
 109
 110         for (i = 0; i < rdebug.num_regulators; i++) {
 111                 struct dbx500_regulator_info *info;
 112                 /* Access per-regulator data */
 113                 info = &rdebug.regulator_array[i];
 114
 115                 /* print status */
 116                 seq_printf(s, "%20s : %8s : %8s : %8s\n",
 117                            info->desc.name,
 118                            info->is_enabled ? "enabled" : "disabled",
 119                            rdebug.state_before_suspend[i] ? "enabled" : "disabled",
 120                            rdebug.state_after_suspend[i] ? "enabled" : "disabled");
 121         }
 122
 123         return 0;
 124 }
 125
 126 static int ux500_regulator_status_open(struct inode *inode, struct file *file)
 127 {
 128         return single_open(file, ux500_regulator_status_print,
 129                 inode->i_private);
 130 }
 131
 132 static const struct file_operations ux500_regulator_status_fops = {
 133         .open = ux500_regulator_status_open,
 134         .read = seq_read,
 135         .llseek = seq_lseek,
 136         .release = single_release,
 137         .owner = THIS_MODULE,
 138 };
 139
 140 int __attribute__((weak)) dbx500_regulator_testcase(
 141         struct dbx500_regulator_info *regulator_info,
 142         int num_regulators)
 143 {
 144         return 0;
 145 }
 146
 147 int
 148 ux500_regulator_debug_init(struct platform_device *pdev,
 149         struct dbx500_regulator_info *regulator_info,
 150         int num_regulators)
 151 {
 152         /* create directory */
 153         rdebug.dir = debugfs_create_dir("ux500-regulator", NULL);
 154         if (!rdebug.dir)
 155                 goto exit_no_debugfs;
 156
 157         /* create "status" file */
 158         rdebug.status_file = debugfs_create_file("status",
 159                 S_IRUGO, rdebug.dir, &pdev->dev,
 160                 &ux500_regulator_status_fops);
 161         if (!rdebug.status_file)
 162                 goto exit_destroy_dir;
 163
 164         /* create "power-state-count" file */
 165         rdebug.power_state_cnt_file = debugfs_create_file("power-state-count",
 166                 S_IRUGO, rdebug.dir, &pdev->dev,
 167                 &ux500_regulator_power_state_cnt_fops);
 168         if (!rdebug.power_state_cnt_file)
 169                 goto exit_destroy_status;
 170
 171         rdebug.regulator_array = regulator_info;
 172         rdebug.num_regulators = num_regulators;
 173
 174         rdebug.state_before_suspend = kzalloc(num_regulators, GFP_KERNEL);
 175         if (!rdebug.state_before_suspend)
 176                 goto exit_destroy_power_state;
 177
 178         rdebug.state_after_suspend = kzalloc(num_regulators, GFP_KERNEL);
 179         if (!rdebug.state_after_suspend)
 180                 goto exit_free;
 181
 182         dbx500_regulator_testcase(regulator_info, num_regulators);
 183         return 0;
 184
 185 exit_free:
 186         kfree(rdebug.state_before_suspend);
 187 exit_destroy_power_state:
 188         debugfs_remove(rdebug.power_state_cnt_file);
 189 exit_destroy_status:
 190         debugfs_remove(rdebug.status_file);
 191 exit_destroy_dir:
 192         debugfs_remove(rdebug.dir);
 193 exit_no_debugfs:
 194         dev_err(&pdev->dev, "failed to create debugfs entries.\n");
 195         return -ENOMEM;
 196 }
 197
 198 int ux500_regulator_debug_exit(void)
 199 {
 200         debugfs_remove_recursive(rdebug.dir);
 201         kfree(rdebug.state_after_suspend);
 202         kfree(rdebug.state_before_suspend);
 203
 204         return 0;
 205 }
 206 #endif