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 	struct device *dev = s->private;
99 	int err;
100 
101 	/* print power state count */
102 	err = seq_printf(s, "ux500-regulator power state count: %i\n",
103 		power_state_active_get());
104 	if (err < 0)
105 		dev_err(dev, "seq_printf overflow\n");
106 
107 	return 0;
108 }
109 
110 static int ux500_regulator_power_state_cnt_open(struct inode *inode,
111 	struct file *file)
112 {
113 	return single_open(file, ux500_regulator_power_state_cnt_print,
114 		inode->i_private);
115 }
116 
117 static const struct file_operations ux500_regulator_power_state_cnt_fops = {
118 	.open = ux500_regulator_power_state_cnt_open,
119 	.read = seq_read,
120 	.llseek = seq_lseek,
121 	.release = single_release,
122 	.owner = THIS_MODULE,
123 };
124 
125 static int ux500_regulator_status_print(struct seq_file *s, void *p)
126 {
127 	struct device *dev = s->private;
128 	int err;
129 	int i;
130 
131 	/* print dump header */
132 	err = seq_puts(s, "ux500-regulator status:\n");
133 	if (err < 0)
134 		dev_err(dev, "seq_puts overflow\n");
135 
136 	err = seq_printf(s, "%31s : %8s : %8s\n", "current",
137 		"before", "after");
138 	if (err < 0)
139 		dev_err(dev, "seq_printf overflow\n");
140 
141 	for (i = 0; i < rdebug.num_regulators; i++) {
142 		struct dbx500_regulator_info *info;
143 		/* Access per-regulator data */
144 		info = &rdebug.regulator_array[i];
145 
146 		/* print status */
147 		err = seq_printf(s, "%20s : %8s : %8s : %8s\n", info->desc.name,
148 			info->is_enabled ? "enabled" : "disabled",
149 			rdebug.state_before_suspend[i] ? "enabled" : "disabled",
150 			rdebug.state_after_suspend[i] ? "enabled" : "disabled");
151 		if (err < 0)
152 			dev_err(dev, "seq_printf overflow\n");
153 	}
154 
155 	return 0;
156 }
157 
158 static int ux500_regulator_status_open(struct inode *inode, struct file *file)
159 {
160 	return single_open(file, ux500_regulator_status_print,
161 		inode->i_private);
162 }
163 
164 static const struct file_operations ux500_regulator_status_fops = {
165 	.open = ux500_regulator_status_open,
166 	.read = seq_read,
167 	.llseek = seq_lseek,
168 	.release = single_release,
169 	.owner = THIS_MODULE,
170 };
171 
172 int __attribute__((weak)) dbx500_regulator_testcase(
173 	struct dbx500_regulator_info *regulator_info,
174 	int num_regulators)
175 {
176 	return 0;
177 }
178 
179 int
180 ux500_regulator_debug_init(struct platform_device *pdev,
181 	struct dbx500_regulator_info *regulator_info,
182 	int num_regulators)
183 {
184 	/* create directory */
185 	rdebug.dir = debugfs_create_dir("ux500-regulator", NULL);
186 	if (!rdebug.dir)
187 		goto exit_no_debugfs;
188 
189 	/* create "status" file */
190 	rdebug.status_file = debugfs_create_file("status",
191 		S_IRUGO, rdebug.dir, &pdev->dev,
192 		&ux500_regulator_status_fops);
193 	if (!rdebug.status_file)
194 		goto exit_destroy_dir;
195 
196 	/* create "power-state-count" file */
197 	rdebug.power_state_cnt_file = debugfs_create_file("power-state-count",
198 		S_IRUGO, rdebug.dir, &pdev->dev,
199 		&ux500_regulator_power_state_cnt_fops);
200 	if (!rdebug.power_state_cnt_file)
201 		goto exit_destroy_status;
202 
203 	rdebug.regulator_array = regulator_info;
204 	rdebug.num_regulators = num_regulators;
205 
206 	rdebug.state_before_suspend = kzalloc(num_regulators, GFP_KERNEL);
207 	if (!rdebug.state_before_suspend)
208 		goto exit_destroy_power_state;
209 
210 	rdebug.state_after_suspend = kzalloc(num_regulators, GFP_KERNEL);
211 	if (!rdebug.state_after_suspend)
212 		goto exit_free;
213 
214 	dbx500_regulator_testcase(regulator_info, num_regulators);
215 	return 0;
216 
217 exit_free:
218 	kfree(rdebug.state_before_suspend);
219 exit_destroy_power_state:
220 	debugfs_remove(rdebug.power_state_cnt_file);
221 exit_destroy_status:
222 	debugfs_remove(rdebug.status_file);
223 exit_destroy_dir:
224 	debugfs_remove(rdebug.dir);
225 exit_no_debugfs:
226 	dev_err(&pdev->dev, "failed to create debugfs entries.\n");
227 	return -ENOMEM;
228 }
229 
230 int ux500_regulator_debug_exit(void)
231 {
232 	debugfs_remove_recursive(rdebug.dir);
233 	kfree(rdebug.state_after_suspend);
234 	kfree(rdebug.state_before_suspend);
235 
236 	return 0;
237 }
238 #endif
239