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 
18 #include "dbx500-prcmu.h"
19 
20 /*
21  * power state reference count
22  */
23 static int power_state_active_cnt; /* will initialize to zero */
24 static DEFINE_SPINLOCK(power_state_active_lock);
25 
26 int power_state_active_get(void)
27 {
28 	unsigned long flags;
29 	int cnt;
30 
31 	spin_lock_irqsave(&power_state_active_lock, flags);
32 	cnt = power_state_active_cnt;
33 	spin_unlock_irqrestore(&power_state_active_lock, flags);
34 
35 	return cnt;
36 }
37 
38 void power_state_active_enable(void)
39 {
40 	unsigned long flags;
41 
42 	spin_lock_irqsave(&power_state_active_lock, flags);
43 	power_state_active_cnt++;
44 	spin_unlock_irqrestore(&power_state_active_lock, flags);
45 }
46 
47 int power_state_active_disable(void)
48 {
49 	int ret = 0;
50 	unsigned long flags;
51 
52 	spin_lock_irqsave(&power_state_active_lock, flags);
53 	if (power_state_active_cnt <= 0) {
54 		pr_err("power state: unbalanced enable/disable calls\n");
55 		ret = -EINVAL;
56 		goto out;
57 	}
58 
59 	power_state_active_cnt--;
60 out:
61 	spin_unlock_irqrestore(&power_state_active_lock, flags);
62 	return ret;
63 }
64 
65 #ifdef CONFIG_REGULATOR_DEBUG
66 
67 static struct ux500_regulator_debug {
68 	struct dentry *dir;
69 	struct dentry *status_file;
70 	struct dentry *power_state_cnt_file;
71 	struct dbx500_regulator_info *regulator_array;
72 	int num_regulators;
73 	u8 *state_before_suspend;
74 	u8 *state_after_suspend;
75 } rdebug;
76 
77 void ux500_regulator_suspend_debug(void)
78 {
79 	int i;
80 	for (i = 0; i < rdebug.num_regulators; i++)
81 		rdebug.state_before_suspend[i] =
82 			rdebug.regulator_array[i].is_enabled;
83 }
84 
85 void ux500_regulator_resume_debug(void)
86 {
87 	int i;
88 	for (i = 0; i < rdebug.num_regulators; i++)
89 		rdebug.state_after_suspend[i] =
90 			rdebug.regulator_array[i].is_enabled;
91 }
92 
93 static int ux500_regulator_power_state_cnt_print(struct seq_file *s, void *p)
94 {
95 	struct device *dev = s->private;
96 	int err;
97 
98 	/* print power state count */
99 	err = seq_printf(s, "ux500-regulator power state count: %i\n",
100 		power_state_active_get());
101 	if (err < 0)
102 		dev_err(dev, "seq_printf overflow\n");
103 
104 	return 0;
105 }
106 
107 static int ux500_regulator_power_state_cnt_open(struct inode *inode,
108 	struct file *file)
109 {
110 	return single_open(file, ux500_regulator_power_state_cnt_print,
111 		inode->i_private);
112 }
113 
114 static const struct file_operations ux500_regulator_power_state_cnt_fops = {
115 	.open = ux500_regulator_power_state_cnt_open,
116 	.read = seq_read,
117 	.llseek = seq_lseek,
118 	.release = single_release,
119 	.owner = THIS_MODULE,
120 };
121 
122 static int ux500_regulator_status_print(struct seq_file *s, void *p)
123 {
124 	struct device *dev = s->private;
125 	int err;
126 	int i;
127 
128 	/* print dump header */
129 	err = seq_printf(s, "ux500-regulator status:\n");
130 	if (err < 0)
131 		dev_err(dev, "seq_printf overflow\n");
132 
133 	err = seq_printf(s, "%31s : %8s : %8s\n", "current",
134 		"before", "after");
135 	if (err < 0)
136 		dev_err(dev, "seq_printf overflow\n");
137 
138 	for (i = 0; i < rdebug.num_regulators; i++) {
139 		struct dbx500_regulator_info *info;
140 		/* Access per-regulator data */
141 		info = &rdebug.regulator_array[i];
142 
143 		/* print status */
144 		err = seq_printf(s, "%20s : %8s : %8s : %8s\n", info->desc.name,
145 			info->is_enabled ? "enabled" : "disabled",
146 			rdebug.state_before_suspend[i] ? "enabled" : "disabled",
147 			rdebug.state_after_suspend[i] ? "enabled" : "disabled");
148 		if (err < 0)
149 			dev_err(dev, "seq_printf overflow\n");
150 	}
151 
152 	return 0;
153 }
154 
155 static int ux500_regulator_status_open(struct inode *inode, struct file *file)
156 {
157 	return single_open(file, ux500_regulator_status_print,
158 		inode->i_private);
159 }
160 
161 static const struct file_operations ux500_regulator_status_fops = {
162 	.open = ux500_regulator_status_open,
163 	.read = seq_read,
164 	.llseek = seq_lseek,
165 	.release = single_release,
166 	.owner = THIS_MODULE,
167 };
168 
169 int __attribute__((weak)) dbx500_regulator_testcase(
170 	struct dbx500_regulator_info *regulator_info,
171 	int num_regulators)
172 {
173 	return 0;
174 }
175 
176 int __devinit
177 ux500_regulator_debug_init(struct platform_device *pdev,
178 	struct dbx500_regulator_info *regulator_info,
179 	int num_regulators)
180 {
181 	/* create directory */
182 	rdebug.dir = debugfs_create_dir("ux500-regulator", NULL);
183 	if (!rdebug.dir)
184 		goto exit_no_debugfs;
185 
186 	/* create "status" file */
187 	rdebug.status_file = debugfs_create_file("status",
188 		S_IRUGO, rdebug.dir, &pdev->dev,
189 		&ux500_regulator_status_fops);
190 	if (!rdebug.status_file)
191 		goto exit_destroy_dir;
192 
193 	/* create "power-state-count" file */
194 	rdebug.power_state_cnt_file = debugfs_create_file("power-state-count",
195 		S_IRUGO, rdebug.dir, &pdev->dev,
196 		&ux500_regulator_power_state_cnt_fops);
197 	if (!rdebug.power_state_cnt_file)
198 		goto exit_destroy_status;
199 
200 	rdebug.regulator_array = regulator_info;
201 	rdebug.num_regulators = num_regulators;
202 
203 	rdebug.state_before_suspend = kzalloc(num_regulators, GFP_KERNEL);
204 	if (!rdebug.state_before_suspend) {
205 		dev_err(&pdev->dev,
206 			"could not allocate memory for saving state\n");
207 		goto exit_destroy_power_state;
208 	}
209 
210 	rdebug.state_after_suspend = kzalloc(num_regulators, GFP_KERNEL);
211 	if (!rdebug.state_after_suspend) {
212 		dev_err(&pdev->dev,
213 			"could not allocate memory for saving state\n");
214 		goto exit_free;
215 	}
216 
217 	dbx500_regulator_testcase(regulator_info, num_regulators);
218 	return 0;
219 
220 exit_free:
221 	kfree(rdebug.state_before_suspend);
222 exit_destroy_power_state:
223 	debugfs_remove(rdebug.power_state_cnt_file);
224 exit_destroy_status:
225 	debugfs_remove(rdebug.status_file);
226 exit_destroy_dir:
227 	debugfs_remove(rdebug.dir);
228 exit_no_debugfs:
229 	dev_err(&pdev->dev, "failed to create debugfs entries.\n");
230 	return -ENOMEM;
231 }
232 
233 int __devexit ux500_regulator_debug_exit(void)
234 {
235 	debugfs_remove_recursive(rdebug.dir);
236 	kfree(rdebug.state_after_suspend);
237 	kfree(rdebug.state_before_suspend);
238 
239 	return 0;
240 }
241 #endif
242