xref: /linux/drivers/extcon/devres.c (revision cf21f328fcafacf4f96e7a30ef9dceede1076378)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * drivers/extcon/devres.c - EXTCON device's resource management
4  *
5  * Copyright (C) 2016 Samsung Electronics
6  * Author: Chanwoo Choi <cw00.choi@samsung.com>
7  */
8 
9 #include "extcon.h"
10 
11 static int devm_extcon_dev_match(struct device *dev, void *res, void *data)
12 {
13 	struct extcon_dev **r = res;
14 
15 	if (WARN_ON(!r || !*r))
16 		return 0;
17 
18 	return *r == data;
19 }
20 
21 static void devm_extcon_dev_release(struct device *dev, void *res)
22 {
23 	extcon_dev_free(*(struct extcon_dev **)res);
24 }
25 
26 
27 static void devm_extcon_dev_unreg(struct device *dev, void *res)
28 {
29 	extcon_dev_unregister(*(struct extcon_dev **)res);
30 }
31 
32 struct extcon_dev_notifier_devres {
33 	struct extcon_dev *edev;
34 	unsigned int id;
35 	struct notifier_block *nb;
36 };
37 
38 static void devm_extcon_dev_notifier_unreg(struct device *dev, void *res)
39 {
40 	struct extcon_dev_notifier_devres *this = res;
41 
42 	extcon_unregister_notifier(this->edev, this->id, this->nb);
43 }
44 
45 static void devm_extcon_dev_notifier_all_unreg(struct device *dev, void *res)
46 {
47 	struct extcon_dev_notifier_devres *this = res;
48 
49 	extcon_unregister_notifier_all(this->edev, this->nb);
50 }
51 
52 /**
53  * devm_extcon_dev_allocate - Allocate managed extcon device
54  * @dev:		the device owning the extcon device being created
55  * @supported_cable:	the array of the supported external connectors
56  *			ending with EXTCON_NONE.
57  *
58  * This function manages automatically the memory of extcon device using device
59  * resource management and simplify the control of freeing the memory of extcon
60  * device.
61  *
62  * Returns the pointer memory of allocated extcon_dev if success
63  * or ERR_PTR(err) if fail
64  */
65 struct extcon_dev *devm_extcon_dev_allocate(struct device *dev,
66 					const unsigned int *supported_cable)
67 {
68 	struct extcon_dev **ptr, *edev;
69 
70 	ptr = devres_alloc(devm_extcon_dev_release, sizeof(*ptr), GFP_KERNEL);
71 	if (!ptr)
72 		return ERR_PTR(-ENOMEM);
73 
74 	edev = extcon_dev_allocate(supported_cable);
75 	if (IS_ERR(edev)) {
76 		devres_free(ptr);
77 		return edev;
78 	}
79 
80 	edev->dev.parent = dev;
81 
82 	*ptr = edev;
83 	devres_add(dev, ptr);
84 
85 	return edev;
86 }
87 EXPORT_SYMBOL_GPL(devm_extcon_dev_allocate);
88 
89 /**
90  * devm_extcon_dev_free() - Resource-managed extcon_dev_unregister()
91  * @dev:	the device owning the extcon device being created
92  * @edev:	the extcon device to be freed
93  *
94  * Free the memory that is allocated with devm_extcon_dev_allocate()
95  * function.
96  */
97 void devm_extcon_dev_free(struct device *dev, struct extcon_dev *edev)
98 {
99 	WARN_ON(devres_release(dev, devm_extcon_dev_release,
100 			       devm_extcon_dev_match, edev));
101 }
102 EXPORT_SYMBOL_GPL(devm_extcon_dev_free);
103 
104 /**
105  * devm_extcon_dev_register() - Resource-managed extcon_dev_register()
106  * @dev:	the device owning the extcon device being created
107  * @edev:	the extcon device to be registered
108  *
109  * this function, that extcon device is automatically unregistered on driver
110  * detach. Internally this function calls extcon_dev_register() function.
111  * To get more information, refer that function.
112  *
113  * If extcon device is registered with this function and the device needs to be
114  * unregistered separately, devm_extcon_dev_unregister() should be used.
115  *
116  * Returns 0 if success or negaive error number if failure.
117  */
118 int devm_extcon_dev_register(struct device *dev, struct extcon_dev *edev)
119 {
120 	struct extcon_dev **ptr;
121 	int ret;
122 
123 	ptr = devres_alloc(devm_extcon_dev_unreg, sizeof(*ptr), GFP_KERNEL);
124 	if (!ptr)
125 		return -ENOMEM;
126 
127 	ret = extcon_dev_register(edev);
128 	if (ret) {
129 		devres_free(ptr);
130 		return ret;
131 	}
132 
133 	*ptr = edev;
134 	devres_add(dev, ptr);
135 
136 	return 0;
137 }
138 EXPORT_SYMBOL_GPL(devm_extcon_dev_register);
139 
140 /**
141  * devm_extcon_dev_unregister() - Resource-managed extcon_dev_unregister()
142  * @dev:	the device owning the extcon device being created
143  * @edev:	the extcon device to unregistered
144  *
145  * Unregister extcon device that is registered with devm_extcon_dev_register()
146  * function.
147  */
148 void devm_extcon_dev_unregister(struct device *dev, struct extcon_dev *edev)
149 {
150 	WARN_ON(devres_release(dev, devm_extcon_dev_unreg,
151 			       devm_extcon_dev_match, edev));
152 }
153 EXPORT_SYMBOL_GPL(devm_extcon_dev_unregister);
154 
155 /**
156  * devm_extcon_register_notifier() - Resource-managed extcon_register_notifier()
157  * @dev:	the device owning the extcon device being created
158  * @edev:	the extcon device
159  * @id:		the unique id among the extcon enumeration
160  * @nb:		a notifier block to be registered
161  *
162  * This function manages automatically the notifier of extcon device using
163  * device resource management and simplify the control of unregistering
164  * the notifier of extcon device.
165  *
166  * Note that the second parameter given to the callback of nb (val) is
167  * "old_state", not the current state. The current state can be retrieved
168  * by looking at the third pameter (edev pointer)'s state value.
169  *
170  * Returns 0 if success or negaive error number if failure.
171  */
172 int devm_extcon_register_notifier(struct device *dev, struct extcon_dev *edev,
173 				unsigned int id, struct notifier_block *nb)
174 {
175 	struct extcon_dev_notifier_devres *ptr;
176 	int ret;
177 
178 	ptr = devres_alloc(devm_extcon_dev_notifier_unreg, sizeof(*ptr),
179 				GFP_KERNEL);
180 	if (!ptr)
181 		return -ENOMEM;
182 
183 	ret = extcon_register_notifier(edev, id, nb);
184 	if (ret) {
185 		devres_free(ptr);
186 		return ret;
187 	}
188 
189 	ptr->edev = edev;
190 	ptr->id = id;
191 	ptr->nb = nb;
192 	devres_add(dev, ptr);
193 
194 	return 0;
195 }
196 EXPORT_SYMBOL(devm_extcon_register_notifier);
197 
198 /**
199  * devm_extcon_unregister_notifier()
200  *			- Resource-managed extcon_unregister_notifier()
201  * @dev:	the device owning the extcon device being created
202  * @edev:	the extcon device
203  * @id:		the unique id among the extcon enumeration
204  * @nb:		a notifier block to be registered
205  */
206 void devm_extcon_unregister_notifier(struct device *dev,
207 				struct extcon_dev *edev, unsigned int id,
208 				struct notifier_block *nb)
209 {
210 	WARN_ON(devres_release(dev, devm_extcon_dev_notifier_unreg,
211 			       devm_extcon_dev_match, edev));
212 }
213 EXPORT_SYMBOL(devm_extcon_unregister_notifier);
214 
215 /**
216  * devm_extcon_register_notifier_all()
217  *		- Resource-managed extcon_register_notifier_all()
218  * @dev:	the device owning the extcon device being created
219  * @edev:	the extcon device
220  * @nb:		a notifier block to be registered
221  *
222  * This function manages automatically the notifier of extcon device using
223  * device resource management and simplify the control of unregistering
224  * the notifier of extcon device. To get more information, refer that function.
225  *
226  * Returns 0 if success or negaive error number if failure.
227  */
228 int devm_extcon_register_notifier_all(struct device *dev, struct extcon_dev *edev,
229 				struct notifier_block *nb)
230 {
231 	struct extcon_dev_notifier_devres *ptr;
232 	int ret;
233 
234 	ptr = devres_alloc(devm_extcon_dev_notifier_all_unreg, sizeof(*ptr),
235 				GFP_KERNEL);
236 	if (!ptr)
237 		return -ENOMEM;
238 
239 	ret = extcon_register_notifier_all(edev, nb);
240 	if (ret) {
241 		devres_free(ptr);
242 		return ret;
243 	}
244 
245 	ptr->edev = edev;
246 	ptr->nb = nb;
247 	devres_add(dev, ptr);
248 
249 	return 0;
250 }
251 EXPORT_SYMBOL(devm_extcon_register_notifier_all);
252 
253 /**
254  * devm_extcon_unregister_notifier_all()
255  *		- Resource-managed extcon_unregister_notifier_all()
256  * @dev:	the device owning the extcon device being created
257  * @edev:	the extcon device
258  * @nb:		a notifier block to be registered
259  */
260 void devm_extcon_unregister_notifier_all(struct device *dev,
261 				struct extcon_dev *edev,
262 				struct notifier_block *nb)
263 {
264 	WARN_ON(devres_release(dev, devm_extcon_dev_notifier_all_unreg,
265 			       devm_extcon_dev_match, edev));
266 }
267 EXPORT_SYMBOL(devm_extcon_unregister_notifier_all);
268