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
225