1 /*
2  * Debug support for HID Nintendo Wii / Wii U peripherals
3  * Copyright (c) 2011-2013 David Herrmann <dh.herrmann@gmail.com>
4  */
5 
6 /*
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License as published by the Free
9  * Software Foundation; either version 2 of the License, or (at your option)
10  * any later version.
11  */
12 
13 #include <linux/debugfs.h>
14 #include <linux/module.h>
15 #include <linux/seq_file.h>
16 #include <linux/spinlock.h>
17 #include <linux/uaccess.h>
18 #include "hid-wiimote.h"
19 
20 struct wiimote_debug {
21 	struct wiimote_data *wdata;
22 	struct dentry *eeprom;
23 	struct dentry *drm;
24 };
25 
26 static ssize_t wiidebug_eeprom_read(struct file *f, char __user *u, size_t s,
27 								loff_t *off)
28 {
29 	struct wiimote_debug *dbg = f->private_data;
30 	struct wiimote_data *wdata = dbg->wdata;
31 	unsigned long flags;
32 	ssize_t ret;
33 	char buf[16];
34 	__u16 size = 0;
35 
36 	if (s == 0)
37 		return -EINVAL;
38 	if (*off > 0xffffff)
39 		return 0;
40 	if (s > 16)
41 		s = 16;
42 
43 	ret = wiimote_cmd_acquire(wdata);
44 	if (ret)
45 		return ret;
46 
47 	spin_lock_irqsave(&wdata->state.lock, flags);
48 	wdata->state.cmd_read_size = s;
49 	wdata->state.cmd_read_buf = buf;
50 	wiimote_cmd_set(wdata, WIIPROTO_REQ_RMEM, *off & 0xffff);
51 	wiiproto_req_reeprom(wdata, *off, s);
52 	spin_unlock_irqrestore(&wdata->state.lock, flags);
53 
54 	ret = wiimote_cmd_wait(wdata);
55 	if (!ret)
56 		size = wdata->state.cmd_read_size;
57 
58 	spin_lock_irqsave(&wdata->state.lock, flags);
59 	wdata->state.cmd_read_buf = NULL;
60 	spin_unlock_irqrestore(&wdata->state.lock, flags);
61 
62 	wiimote_cmd_release(wdata);
63 
64 	if (ret)
65 		return ret;
66 	else if (size == 0)
67 		return -EIO;
68 
69 	if (copy_to_user(u, buf, size))
70 		return -EFAULT;
71 
72 	*off += size;
73 	ret = size;
74 
75 	return ret;
76 }
77 
78 static const struct file_operations wiidebug_eeprom_fops = {
79 	.owner = THIS_MODULE,
80 	.open = simple_open,
81 	.read = wiidebug_eeprom_read,
82 	.llseek = generic_file_llseek,
83 };
84 
85 static const char *wiidebug_drmmap[] = {
86 	[WIIPROTO_REQ_NULL] = "NULL",
87 	[WIIPROTO_REQ_DRM_K] = "K",
88 	[WIIPROTO_REQ_DRM_KA] = "KA",
89 	[WIIPROTO_REQ_DRM_KE] = "KE",
90 	[WIIPROTO_REQ_DRM_KAI] = "KAI",
91 	[WIIPROTO_REQ_DRM_KEE] = "KEE",
92 	[WIIPROTO_REQ_DRM_KAE] = "KAE",
93 	[WIIPROTO_REQ_DRM_KIE] = "KIE",
94 	[WIIPROTO_REQ_DRM_KAIE] = "KAIE",
95 	[WIIPROTO_REQ_DRM_E] = "E",
96 	[WIIPROTO_REQ_DRM_SKAI1] = "SKAI1",
97 	[WIIPROTO_REQ_DRM_SKAI2] = "SKAI2",
98 	[WIIPROTO_REQ_MAX] = NULL
99 };
100 
101 static int wiidebug_drm_show(struct seq_file *f, void *p)
102 {
103 	struct wiimote_debug *dbg = f->private;
104 	const char *str = NULL;
105 	unsigned long flags;
106 	__u8 drm;
107 
108 	spin_lock_irqsave(&dbg->wdata->state.lock, flags);
109 	drm = dbg->wdata->state.drm;
110 	spin_unlock_irqrestore(&dbg->wdata->state.lock, flags);
111 
112 	if (drm < WIIPROTO_REQ_MAX)
113 		str = wiidebug_drmmap[drm];
114 	if (!str)
115 		str = "unknown";
116 
117 	seq_printf(f, "%s\n", str);
118 
119 	return 0;
120 }
121 
122 static int wiidebug_drm_open(struct inode *i, struct file *f)
123 {
124 	return single_open(f, wiidebug_drm_show, i->i_private);
125 }
126 
127 static ssize_t wiidebug_drm_write(struct file *f, const char __user *u,
128 							size_t s, loff_t *off)
129 {
130 	struct seq_file *sf = f->private_data;
131 	struct wiimote_debug *dbg = sf->private;
132 	unsigned long flags;
133 	char buf[16];
134 	ssize_t len;
135 	int i;
136 
137 	if (s == 0)
138 		return -EINVAL;
139 
140 	len = min((size_t) 15, s);
141 	if (copy_from_user(buf, u, len))
142 		return -EFAULT;
143 
144 	buf[len] = 0;
145 
146 	for (i = 0; i < WIIPROTO_REQ_MAX; ++i) {
147 		if (!wiidebug_drmmap[i])
148 			continue;
149 		if (!strcasecmp(buf, wiidebug_drmmap[i]))
150 			break;
151 	}
152 
153 	if (i == WIIPROTO_REQ_MAX)
154 		i = simple_strtoul(buf, NULL, 16);
155 
156 	spin_lock_irqsave(&dbg->wdata->state.lock, flags);
157 	dbg->wdata->state.flags &= ~WIIPROTO_FLAG_DRM_LOCKED;
158 	wiiproto_req_drm(dbg->wdata, (__u8) i);
159 	if (i != WIIPROTO_REQ_NULL)
160 		dbg->wdata->state.flags |= WIIPROTO_FLAG_DRM_LOCKED;
161 	spin_unlock_irqrestore(&dbg->wdata->state.lock, flags);
162 
163 	return len;
164 }
165 
166 static const struct file_operations wiidebug_drm_fops = {
167 	.owner = THIS_MODULE,
168 	.open = wiidebug_drm_open,
169 	.read = seq_read,
170 	.llseek = seq_lseek,
171 	.write = wiidebug_drm_write,
172 	.release = single_release,
173 };
174 
175 int wiidebug_init(struct wiimote_data *wdata)
176 {
177 	struct wiimote_debug *dbg;
178 	unsigned long flags;
179 	int ret = -ENOMEM;
180 
181 	dbg = kzalloc(sizeof(*dbg), GFP_KERNEL);
182 	if (!dbg)
183 		return -ENOMEM;
184 
185 	dbg->wdata = wdata;
186 
187 	dbg->eeprom = debugfs_create_file("eeprom", S_IRUSR,
188 		dbg->wdata->hdev->debug_dir, dbg, &wiidebug_eeprom_fops);
189 	if (!dbg->eeprom)
190 		goto err;
191 
192 	dbg->drm = debugfs_create_file("drm", S_IRUSR,
193 			dbg->wdata->hdev->debug_dir, dbg, &wiidebug_drm_fops);
194 	if (!dbg->drm)
195 		goto err_drm;
196 
197 	spin_lock_irqsave(&wdata->state.lock, flags);
198 	wdata->debug = dbg;
199 	spin_unlock_irqrestore(&wdata->state.lock, flags);
200 
201 	return 0;
202 
203 err_drm:
204 	debugfs_remove(dbg->eeprom);
205 err:
206 	kfree(dbg);
207 	return ret;
208 }
209 
210 void wiidebug_deinit(struct wiimote_data *wdata)
211 {
212 	struct wiimote_debug *dbg = wdata->debug;
213 	unsigned long flags;
214 
215 	if (!dbg)
216 		return;
217 
218 	spin_lock_irqsave(&wdata->state.lock, flags);
219 	wdata->debug = NULL;
220 	spin_unlock_irqrestore(&wdata->state.lock, flags);
221 
222 	debugfs_remove(dbg->drm);
223 	debugfs_remove(dbg->eeprom);
224 	kfree(dbg);
225 }
226