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
207