Loading...
Note: File does not exist in v3.5.6.
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * USB Type-C Multiplexer/DeMultiplexer Switch support
4 *
5 * Copyright (C) 2018 Intel Corporation
6 * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com>
7 * Hans de Goede <hdegoede@redhat.com>
8 */
9
10#include <linux/device.h>
11#include <linux/list.h>
12#include <linux/module.h>
13#include <linux/mutex.h>
14#include <linux/property.h>
15#include <linux/slab.h>
16#include <linux/usb/typec_mux.h>
17
18#include "bus.h"
19
20static bool dev_name_ends_with(struct device *dev, const char *suffix)
21{
22 const char *name = dev_name(dev);
23 const int name_len = strlen(name);
24 const int suffix_len = strlen(suffix);
25
26 if (suffix_len > name_len)
27 return false;
28
29 return strcmp(name + (name_len - suffix_len), suffix) == 0;
30}
31
32static int switch_fwnode_match(struct device *dev, const void *fwnode)
33{
34 return dev_fwnode(dev) == fwnode && dev_name_ends_with(dev, "-switch");
35}
36
37static void *typec_switch_match(struct device_connection *con, int ep,
38 void *data)
39{
40 struct device *dev;
41
42 if (con->id && !fwnode_property_present(con->fwnode, con->id))
43 return NULL;
44
45 dev = class_find_device(&typec_mux_class, NULL, con->fwnode,
46 switch_fwnode_match);
47
48 return dev ? to_typec_switch(dev) : ERR_PTR(-EPROBE_DEFER);
49}
50
51/**
52 * fwnode_typec_switch_get - Find USB Type-C orientation switch
53 * @fwnode: The caller device node
54 *
55 * Finds a switch linked with @dev. Returns a reference to the switch on
56 * success, NULL if no matching connection was found, or
57 * ERR_PTR(-EPROBE_DEFER) when a connection was found but the switch
58 * has not been enumerated yet.
59 */
60struct typec_switch *fwnode_typec_switch_get(struct fwnode_handle *fwnode)
61{
62 struct typec_switch *sw;
63
64 sw = fwnode_connection_find_match(fwnode, "orientation-switch", NULL,
65 typec_switch_match);
66 if (!IS_ERR_OR_NULL(sw))
67 WARN_ON(!try_module_get(sw->dev.parent->driver->owner));
68
69 return sw;
70}
71EXPORT_SYMBOL_GPL(fwnode_typec_switch_get);
72
73/**
74 * typec_put_switch - Release USB Type-C orientation switch
75 * @sw: USB Type-C orientation switch
76 *
77 * Decrement reference count for @sw.
78 */
79void typec_switch_put(struct typec_switch *sw)
80{
81 if (!IS_ERR_OR_NULL(sw)) {
82 module_put(sw->dev.parent->driver->owner);
83 put_device(&sw->dev);
84 }
85}
86EXPORT_SYMBOL_GPL(typec_switch_put);
87
88static void typec_switch_release(struct device *dev)
89{
90 kfree(to_typec_switch(dev));
91}
92
93static const struct device_type typec_switch_dev_type = {
94 .name = "orientation_switch",
95 .release = typec_switch_release,
96};
97
98/**
99 * typec_switch_register - Register USB Type-C orientation switch
100 * @parent: Parent device
101 * @desc: Orientation switch description
102 *
103 * This function registers a switch that can be used for routing the correct
104 * data pairs depending on the cable plug orientation from the USB Type-C
105 * connector to the USB controllers. USB Type-C plugs can be inserted
106 * right-side-up or upside-down.
107 */
108struct typec_switch *
109typec_switch_register(struct device *parent,
110 const struct typec_switch_desc *desc)
111{
112 struct typec_switch *sw;
113 int ret;
114
115 if (!desc || !desc->set)
116 return ERR_PTR(-EINVAL);
117
118 sw = kzalloc(sizeof(*sw), GFP_KERNEL);
119 if (!sw)
120 return ERR_PTR(-ENOMEM);
121
122 sw->set = desc->set;
123
124 device_initialize(&sw->dev);
125 sw->dev.parent = parent;
126 sw->dev.fwnode = desc->fwnode;
127 sw->dev.class = &typec_mux_class;
128 sw->dev.type = &typec_switch_dev_type;
129 sw->dev.driver_data = desc->drvdata;
130 dev_set_name(&sw->dev, "%s-switch",
131 desc->name ? desc->name : dev_name(parent));
132
133 ret = device_add(&sw->dev);
134 if (ret) {
135 dev_err(parent, "failed to register switch (%d)\n", ret);
136 put_device(&sw->dev);
137 return ERR_PTR(ret);
138 }
139
140 return sw;
141}
142EXPORT_SYMBOL_GPL(typec_switch_register);
143
144int typec_switch_set(struct typec_switch *sw,
145 enum typec_orientation orientation)
146{
147 if (IS_ERR_OR_NULL(sw))
148 return 0;
149
150 return sw->set(sw, orientation);
151}
152EXPORT_SYMBOL_GPL(typec_switch_set);
153
154/**
155 * typec_switch_unregister - Unregister USB Type-C orientation switch
156 * @sw: USB Type-C orientation switch
157 *
158 * Unregister switch that was registered with typec_switch_register().
159 */
160void typec_switch_unregister(struct typec_switch *sw)
161{
162 if (!IS_ERR_OR_NULL(sw))
163 device_unregister(&sw->dev);
164}
165EXPORT_SYMBOL_GPL(typec_switch_unregister);
166
167void typec_switch_set_drvdata(struct typec_switch *sw, void *data)
168{
169 dev_set_drvdata(&sw->dev, data);
170}
171EXPORT_SYMBOL_GPL(typec_switch_set_drvdata);
172
173void *typec_switch_get_drvdata(struct typec_switch *sw)
174{
175 return dev_get_drvdata(&sw->dev);
176}
177EXPORT_SYMBOL_GPL(typec_switch_get_drvdata);
178
179/* ------------------------------------------------------------------------- */
180
181static int mux_fwnode_match(struct device *dev, const void *fwnode)
182{
183 return dev_fwnode(dev) == fwnode && dev_name_ends_with(dev, "-mux");
184}
185
186static void *typec_mux_match(struct device_connection *con, int ep, void *data)
187{
188 const struct typec_altmode_desc *desc = data;
189 struct device *dev;
190 bool match;
191 int nval;
192 u16 *val;
193 int i;
194
195 /*
196 * Check has the identifier already been "consumed". If it
197 * has, no need to do any extra connection identification.
198 */
199 match = !con->id;
200 if (match)
201 goto find_mux;
202
203 /* Accessory Mode muxes */
204 if (!desc) {
205 match = fwnode_property_present(con->fwnode, "accessory");
206 if (match)
207 goto find_mux;
208 return NULL;
209 }
210
211 /* Alternate Mode muxes */
212 nval = fwnode_property_count_u16(con->fwnode, "svid");
213 if (nval <= 0)
214 return NULL;
215
216 val = kcalloc(nval, sizeof(*val), GFP_KERNEL);
217 if (!val)
218 return ERR_PTR(-ENOMEM);
219
220 nval = fwnode_property_read_u16_array(con->fwnode, "svid", val, nval);
221 if (nval < 0) {
222 kfree(val);
223 return ERR_PTR(nval);
224 }
225
226 for (i = 0; i < nval; i++) {
227 match = val[i] == desc->svid;
228 if (match) {
229 kfree(val);
230 goto find_mux;
231 }
232 }
233 kfree(val);
234 return NULL;
235
236find_mux:
237 dev = class_find_device(&typec_mux_class, NULL, con->fwnode,
238 mux_fwnode_match);
239
240 return dev ? to_typec_switch(dev) : ERR_PTR(-EPROBE_DEFER);
241}
242
243/**
244 * fwnode_typec_mux_get - Find USB Type-C Multiplexer
245 * @fwnode: The caller device node
246 * @desc: Alt Mode description
247 *
248 * Finds a mux linked to the caller. This function is primarily meant for the
249 * Type-C drivers. Returns a reference to the mux on success, NULL if no
250 * matching connection was found, or ERR_PTR(-EPROBE_DEFER) when a connection
251 * was found but the mux has not been enumerated yet.
252 */
253struct typec_mux *fwnode_typec_mux_get(struct fwnode_handle *fwnode,
254 const struct typec_altmode_desc *desc)
255{
256 struct typec_mux *mux;
257
258 mux = fwnode_connection_find_match(fwnode, "mode-switch", (void *)desc,
259 typec_mux_match);
260 if (!IS_ERR_OR_NULL(mux))
261 WARN_ON(!try_module_get(mux->dev.parent->driver->owner));
262
263 return mux;
264}
265EXPORT_SYMBOL_GPL(fwnode_typec_mux_get);
266
267/**
268 * typec_mux_put - Release handle to a Multiplexer
269 * @mux: USB Type-C Connector Multiplexer/DeMultiplexer
270 *
271 * Decrements reference count for @mux.
272 */
273void typec_mux_put(struct typec_mux *mux)
274{
275 if (!IS_ERR_OR_NULL(mux)) {
276 module_put(mux->dev.parent->driver->owner);
277 put_device(&mux->dev);
278 }
279}
280EXPORT_SYMBOL_GPL(typec_mux_put);
281
282int typec_mux_set(struct typec_mux *mux, struct typec_mux_state *state)
283{
284 if (IS_ERR_OR_NULL(mux))
285 return 0;
286
287 return mux->set(mux, state);
288}
289EXPORT_SYMBOL_GPL(typec_mux_set);
290
291static void typec_mux_release(struct device *dev)
292{
293 kfree(to_typec_mux(dev));
294}
295
296static const struct device_type typec_mux_dev_type = {
297 .name = "mode_switch",
298 .release = typec_mux_release,
299};
300
301/**
302 * typec_mux_register - Register Multiplexer routing USB Type-C pins
303 * @parent: Parent device
304 * @desc: Multiplexer description
305 *
306 * USB Type-C connectors can be used for alternate modes of operation besides
307 * USB when Accessory/Alternate Modes are supported. With some of those modes,
308 * the pins on the connector need to be reconfigured. This function registers
309 * multiplexer switches routing the pins on the connector.
310 */
311struct typec_mux *
312typec_mux_register(struct device *parent, const struct typec_mux_desc *desc)
313{
314 struct typec_mux *mux;
315 int ret;
316
317 if (!desc || !desc->set)
318 return ERR_PTR(-EINVAL);
319
320 mux = kzalloc(sizeof(*mux), GFP_KERNEL);
321 if (!mux)
322 return ERR_PTR(-ENOMEM);
323
324 mux->set = desc->set;
325
326 device_initialize(&mux->dev);
327 mux->dev.parent = parent;
328 mux->dev.fwnode = desc->fwnode;
329 mux->dev.class = &typec_mux_class;
330 mux->dev.type = &typec_mux_dev_type;
331 mux->dev.driver_data = desc->drvdata;
332 dev_set_name(&mux->dev, "%s-mux",
333 desc->name ? desc->name : dev_name(parent));
334
335 ret = device_add(&mux->dev);
336 if (ret) {
337 dev_err(parent, "failed to register mux (%d)\n", ret);
338 put_device(&mux->dev);
339 return ERR_PTR(ret);
340 }
341
342 return mux;
343}
344EXPORT_SYMBOL_GPL(typec_mux_register);
345
346/**
347 * typec_mux_unregister - Unregister Multiplexer Switch
348 * @mux: USB Type-C Connector Multiplexer/DeMultiplexer
349 *
350 * Unregister mux that was registered with typec_mux_register().
351 */
352void typec_mux_unregister(struct typec_mux *mux)
353{
354 if (!IS_ERR_OR_NULL(mux))
355 device_unregister(&mux->dev);
356}
357EXPORT_SYMBOL_GPL(typec_mux_unregister);
358
359void typec_mux_set_drvdata(struct typec_mux *mux, void *data)
360{
361 dev_set_drvdata(&mux->dev, data);
362}
363EXPORT_SYMBOL_GPL(typec_mux_set_drvdata);
364
365void *typec_mux_get_drvdata(struct typec_mux *mux)
366{
367 return dev_get_drvdata(&mux->dev);
368}
369EXPORT_SYMBOL_GPL(typec_mux_get_drvdata);
370
371struct class typec_mux_class = {
372 .name = "typec_mux",
373 .owner = THIS_MODULE,
374};