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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Greybus "Core"
4 *
5 * Copyright 2014-2015 Google Inc.
6 * Copyright 2014-2015 Linaro Ltd.
7 */
8
9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10
11#define CREATE_TRACE_POINTS
12#include <linux/greybus.h>
13#include "greybus_trace.h"
14
15#define GB_BUNDLE_AUTOSUSPEND_MS 3000
16
17/* Allow greybus to be disabled at boot if needed */
18static bool nogreybus;
19#ifdef MODULE
20module_param(nogreybus, bool, 0444);
21#else
22core_param(nogreybus, nogreybus, bool, 0444);
23#endif
24int greybus_disabled(void)
25{
26 return nogreybus;
27}
28EXPORT_SYMBOL_GPL(greybus_disabled);
29
30static int is_gb_host_device(const struct device *dev)
31{
32 return dev->type == &greybus_hd_type;
33}
34
35static int is_gb_module(const struct device *dev)
36{
37 return dev->type == &greybus_module_type;
38}
39
40static int is_gb_interface(const struct device *dev)
41{
42 return dev->type == &greybus_interface_type;
43}
44
45static int is_gb_control(const struct device *dev)
46{
47 return dev->type == &greybus_control_type;
48}
49
50static int is_gb_bundle(const struct device *dev)
51{
52 return dev->type == &greybus_bundle_type;
53}
54
55static int is_gb_svc(const struct device *dev)
56{
57 return dev->type == &greybus_svc_type;
58}
59
60static bool greybus_match_one_id(struct gb_bundle *bundle,
61 const struct greybus_bundle_id *id)
62{
63 if ((id->match_flags & GREYBUS_ID_MATCH_VENDOR) &&
64 (id->vendor != bundle->intf->vendor_id))
65 return false;
66
67 if ((id->match_flags & GREYBUS_ID_MATCH_PRODUCT) &&
68 (id->product != bundle->intf->product_id))
69 return false;
70
71 if ((id->match_flags & GREYBUS_ID_MATCH_CLASS) &&
72 (id->class != bundle->class))
73 return false;
74
75 return true;
76}
77
78static const struct greybus_bundle_id *
79greybus_match_id(struct gb_bundle *bundle, const struct greybus_bundle_id *id)
80{
81 if (!id)
82 return NULL;
83
84 for (; id->vendor || id->product || id->class || id->driver_info;
85 id++) {
86 if (greybus_match_one_id(bundle, id))
87 return id;
88 }
89
90 return NULL;
91}
92
93static int greybus_match_device(struct device *dev, const struct device_driver *drv)
94{
95 const struct greybus_driver *driver = to_greybus_driver(drv);
96 struct gb_bundle *bundle;
97 const struct greybus_bundle_id *id;
98
99 if (!is_gb_bundle(dev))
100 return 0;
101
102 bundle = to_gb_bundle(dev);
103
104 id = greybus_match_id(bundle, driver->id_table);
105 if (id)
106 return 1;
107 /* FIXME - Dynamic ids? */
108 return 0;
109}
110
111static int greybus_uevent(const struct device *dev, struct kobj_uevent_env *env)
112{
113 const struct gb_host_device *hd;
114 const struct gb_module *module = NULL;
115 const struct gb_interface *intf = NULL;
116 const struct gb_control *control = NULL;
117 const struct gb_bundle *bundle = NULL;
118 const struct gb_svc *svc = NULL;
119
120 if (is_gb_host_device(dev)) {
121 hd = to_gb_host_device(dev);
122 } else if (is_gb_module(dev)) {
123 module = to_gb_module(dev);
124 hd = module->hd;
125 } else if (is_gb_interface(dev)) {
126 intf = to_gb_interface(dev);
127 module = intf->module;
128 hd = intf->hd;
129 } else if (is_gb_control(dev)) {
130 control = to_gb_control(dev);
131 intf = control->intf;
132 module = intf->module;
133 hd = intf->hd;
134 } else if (is_gb_bundle(dev)) {
135 bundle = to_gb_bundle(dev);
136 intf = bundle->intf;
137 module = intf->module;
138 hd = intf->hd;
139 } else if (is_gb_svc(dev)) {
140 svc = to_gb_svc(dev);
141 hd = svc->hd;
142 } else {
143 dev_WARN(dev, "uevent for unknown greybus device \"type\"!\n");
144 return -EINVAL;
145 }
146
147 if (add_uevent_var(env, "BUS=%u", hd->bus_id))
148 return -ENOMEM;
149
150 if (module) {
151 if (add_uevent_var(env, "MODULE=%u", module->module_id))
152 return -ENOMEM;
153 }
154
155 if (intf) {
156 if (add_uevent_var(env, "INTERFACE=%u", intf->interface_id))
157 return -ENOMEM;
158 if (add_uevent_var(env, "GREYBUS_ID=%08x/%08x",
159 intf->vendor_id, intf->product_id))
160 return -ENOMEM;
161 }
162
163 if (bundle) {
164 // FIXME
165 // add a uevent that can "load" a bundle type
166 // This is what we need to bind a driver to so use the info
167 // in gmod here as well
168
169 if (add_uevent_var(env, "BUNDLE=%u", bundle->id))
170 return -ENOMEM;
171 if (add_uevent_var(env, "BUNDLE_CLASS=%02x", bundle->class))
172 return -ENOMEM;
173 }
174
175 return 0;
176}
177
178static void greybus_shutdown(struct device *dev)
179{
180 if (is_gb_host_device(dev)) {
181 struct gb_host_device *hd;
182
183 hd = to_gb_host_device(dev);
184 gb_hd_shutdown(hd);
185 }
186}
187
188static int greybus_probe(struct device *dev)
189{
190 struct greybus_driver *driver = to_greybus_driver(dev->driver);
191 struct gb_bundle *bundle = to_gb_bundle(dev);
192 const struct greybus_bundle_id *id;
193 int retval;
194
195 /* match id */
196 id = greybus_match_id(bundle, driver->id_table);
197 if (!id)
198 return -ENODEV;
199
200 retval = pm_runtime_get_sync(&bundle->intf->dev);
201 if (retval < 0) {
202 pm_runtime_put_noidle(&bundle->intf->dev);
203 return retval;
204 }
205
206 retval = gb_control_bundle_activate(bundle->intf->control, bundle->id);
207 if (retval) {
208 pm_runtime_put(&bundle->intf->dev);
209 return retval;
210 }
211
212 /*
213 * Unbound bundle devices are always deactivated. During probe, the
214 * Runtime PM is set to enabled and active and the usage count is
215 * incremented. If the driver supports runtime PM, it should call
216 * pm_runtime_put() in its probe routine and pm_runtime_get_sync()
217 * in remove routine.
218 */
219 pm_runtime_set_autosuspend_delay(dev, GB_BUNDLE_AUTOSUSPEND_MS);
220 pm_runtime_use_autosuspend(dev);
221 pm_runtime_get_noresume(dev);
222 pm_runtime_set_active(dev);
223 pm_runtime_enable(dev);
224
225 retval = driver->probe(bundle, id);
226 if (retval) {
227 /*
228 * Catch buggy drivers that fail to destroy their connections.
229 */
230 WARN_ON(!list_empty(&bundle->connections));
231
232 gb_control_bundle_deactivate(bundle->intf->control, bundle->id);
233
234 pm_runtime_disable(dev);
235 pm_runtime_set_suspended(dev);
236 pm_runtime_put_noidle(dev);
237 pm_runtime_dont_use_autosuspend(dev);
238 pm_runtime_put(&bundle->intf->dev);
239
240 return retval;
241 }
242
243 pm_runtime_put(&bundle->intf->dev);
244
245 return 0;
246}
247
248static void greybus_remove(struct device *dev)
249{
250 struct greybus_driver *driver = to_greybus_driver(dev->driver);
251 struct gb_bundle *bundle = to_gb_bundle(dev);
252 struct gb_connection *connection;
253 int retval;
254
255 retval = pm_runtime_get_sync(dev);
256 if (retval < 0)
257 dev_err(dev, "failed to resume bundle: %d\n", retval);
258
259 /*
260 * Disable (non-offloaded) connections early in case the interface is
261 * already gone to avoid unceccessary operation timeouts during
262 * driver disconnect. Otherwise, only disable incoming requests.
263 */
264 list_for_each_entry(connection, &bundle->connections, bundle_links) {
265 if (gb_connection_is_offloaded(connection))
266 continue;
267
268 if (bundle->intf->disconnected)
269 gb_connection_disable_forced(connection);
270 else
271 gb_connection_disable_rx(connection);
272 }
273
274 driver->disconnect(bundle);
275
276 /* Catch buggy drivers that fail to destroy their connections. */
277 WARN_ON(!list_empty(&bundle->connections));
278
279 if (!bundle->intf->disconnected)
280 gb_control_bundle_deactivate(bundle->intf->control, bundle->id);
281
282 pm_runtime_put_noidle(dev);
283 pm_runtime_disable(dev);
284 pm_runtime_set_suspended(dev);
285 pm_runtime_dont_use_autosuspend(dev);
286 pm_runtime_put_noidle(dev);
287}
288
289const struct bus_type greybus_bus_type = {
290 .name = "greybus",
291 .match = greybus_match_device,
292 .uevent = greybus_uevent,
293 .probe = greybus_probe,
294 .remove = greybus_remove,
295 .shutdown = greybus_shutdown,
296};
297
298int greybus_register_driver(struct greybus_driver *driver, struct module *owner,
299 const char *mod_name)
300{
301 int retval;
302
303 if (greybus_disabled())
304 return -ENODEV;
305
306 driver->driver.bus = &greybus_bus_type;
307 driver->driver.name = driver->name;
308 driver->driver.owner = owner;
309 driver->driver.mod_name = mod_name;
310
311 retval = driver_register(&driver->driver);
312 if (retval)
313 return retval;
314
315 pr_info("registered new driver %s\n", driver->name);
316 return 0;
317}
318EXPORT_SYMBOL_GPL(greybus_register_driver);
319
320void greybus_deregister_driver(struct greybus_driver *driver)
321{
322 driver_unregister(&driver->driver);
323}
324EXPORT_SYMBOL_GPL(greybus_deregister_driver);
325
326static int __init gb_init(void)
327{
328 int retval;
329
330 if (greybus_disabled())
331 return -ENODEV;
332
333 BUILD_BUG_ON(CPORT_ID_MAX >= (long)CPORT_ID_BAD);
334
335 gb_debugfs_init();
336
337 retval = bus_register(&greybus_bus_type);
338 if (retval) {
339 pr_err("bus_register failed (%d)\n", retval);
340 goto error_bus;
341 }
342
343 retval = gb_hd_init();
344 if (retval) {
345 pr_err("gb_hd_init failed (%d)\n", retval);
346 goto error_hd;
347 }
348
349 retval = gb_operation_init();
350 if (retval) {
351 pr_err("gb_operation_init failed (%d)\n", retval);
352 goto error_operation;
353 }
354 return 0; /* Success */
355
356error_operation:
357 gb_hd_exit();
358error_hd:
359 bus_unregister(&greybus_bus_type);
360error_bus:
361 gb_debugfs_cleanup();
362
363 return retval;
364}
365module_init(gb_init);
366
367static void __exit gb_exit(void)
368{
369 gb_operation_exit();
370 gb_hd_exit();
371 bus_unregister(&greybus_bus_type);
372 gb_debugfs_cleanup();
373 tracepoint_synchronize_unregister();
374}
375module_exit(gb_exit);
376MODULE_DESCRIPTION("Greybus core driver");
377MODULE_LICENSE("GPL v2");
378MODULE_AUTHOR("Greg Kroah-Hartman <[email protected]>");