1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Provides code common for host and device side USB.
4 *
5 * If either host side (ie. CONFIG_USB=y) or device side USB stack
6 * (ie. CONFIG_USB_GADGET=y) is compiled in the kernel, this module is
7 * compiled-in as well. Otherwise, if either of the two stacks is
8 * compiled as module, this file is compiled as module as well.
9 */
10
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/platform_device.h>
15 #include <linux/usb/ch9.h>
16 #include <linux/usb/of.h>
17 #include <linux/usb/otg.h>
18 #include <linux/of_platform.h>
19 #include <linux/debugfs.h>
20 #include "common.h"
21
22 static const char *const ep_type_names[] = {
23 [USB_ENDPOINT_XFER_CONTROL] = "ctrl",
24 [USB_ENDPOINT_XFER_ISOC] = "isoc",
25 [USB_ENDPOINT_XFER_BULK] = "bulk",
26 [USB_ENDPOINT_XFER_INT] = "intr",
27 };
28
29 /**
30 * usb_ep_type_string() - Returns human readable-name of the endpoint type.
31 * @ep_type: The endpoint type to return human-readable name for. If it's not
32 * any of the types: USB_ENDPOINT_XFER_{CONTROL, ISOC, BULK, INT},
33 * usually got by usb_endpoint_type(), the string 'unknown' will be returned.
34 */
usb_ep_type_string(int ep_type)35 const char *usb_ep_type_string(int ep_type)
36 {
37 if (ep_type < 0 || ep_type >= ARRAY_SIZE(ep_type_names))
38 return "unknown";
39
40 return ep_type_names[ep_type];
41 }
42 EXPORT_SYMBOL_GPL(usb_ep_type_string);
43
usb_otg_state_string(enum usb_otg_state state)44 const char *usb_otg_state_string(enum usb_otg_state state)
45 {
46 static const char *const names[] = {
47 [OTG_STATE_A_IDLE] = "a_idle",
48 [OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise",
49 [OTG_STATE_A_WAIT_BCON] = "a_wait_bcon",
50 [OTG_STATE_A_HOST] = "a_host",
51 [OTG_STATE_A_SUSPEND] = "a_suspend",
52 [OTG_STATE_A_PERIPHERAL] = "a_peripheral",
53 [OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall",
54 [OTG_STATE_A_VBUS_ERR] = "a_vbus_err",
55 [OTG_STATE_B_IDLE] = "b_idle",
56 [OTG_STATE_B_SRP_INIT] = "b_srp_init",
57 [OTG_STATE_B_PERIPHERAL] = "b_peripheral",
58 [OTG_STATE_B_WAIT_ACON] = "b_wait_acon",
59 [OTG_STATE_B_HOST] = "b_host",
60 };
61
62 if (state < 0 || state >= ARRAY_SIZE(names))
63 return "UNDEFINED";
64
65 return names[state];
66 }
67 EXPORT_SYMBOL_GPL(usb_otg_state_string);
68
69 static const char *const speed_names[] = {
70 [USB_SPEED_UNKNOWN] = "UNKNOWN",
71 [USB_SPEED_LOW] = "low-speed",
72 [USB_SPEED_FULL] = "full-speed",
73 [USB_SPEED_HIGH] = "high-speed",
74 [USB_SPEED_WIRELESS] = "wireless",
75 [USB_SPEED_SUPER] = "super-speed",
76 [USB_SPEED_SUPER_PLUS] = "super-speed-plus",
77 };
78
79 static const char *const ssp_rate[] = {
80 [USB_SSP_GEN_UNKNOWN] = "UNKNOWN",
81 [USB_SSP_GEN_2x1] = "super-speed-plus-gen2x1",
82 [USB_SSP_GEN_1x2] = "super-speed-plus-gen1x2",
83 [USB_SSP_GEN_2x2] = "super-speed-plus-gen2x2",
84 };
85
86 /**
87 * usb_speed_string() - Returns human readable-name of the speed.
88 * @speed: The speed to return human-readable name for. If it's not
89 * any of the speeds defined in usb_device_speed enum, string for
90 * USB_SPEED_UNKNOWN will be returned.
91 */
usb_speed_string(enum usb_device_speed speed)92 const char *usb_speed_string(enum usb_device_speed speed)
93 {
94 if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
95 speed = USB_SPEED_UNKNOWN;
96 return speed_names[speed];
97 }
98 EXPORT_SYMBOL_GPL(usb_speed_string);
99
100 /**
101 * usb_get_maximum_speed - Get maximum requested speed for a given USB
102 * controller.
103 * @dev: Pointer to the given USB controller device
104 *
105 * The function gets the maximum speed string from property "maximum-speed",
106 * and returns the corresponding enum usb_device_speed.
107 */
usb_get_maximum_speed(struct device * dev)108 enum usb_device_speed usb_get_maximum_speed(struct device *dev)
109 {
110 const char *maximum_speed;
111 int ret;
112
113 ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
114 if (ret < 0)
115 return USB_SPEED_UNKNOWN;
116
117 ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed);
118 if (ret > 0)
119 return USB_SPEED_SUPER_PLUS;
120
121 ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed);
122 return (ret < 0) ? USB_SPEED_UNKNOWN : ret;
123 }
124 EXPORT_SYMBOL_GPL(usb_get_maximum_speed);
125
126 /**
127 * usb_get_maximum_ssp_rate - Get the signaling rate generation and lane count
128 * of a SuperSpeed Plus capable device.
129 * @dev: Pointer to the given USB controller device
130 *
131 * If the string from "maximum-speed" property is super-speed-plus-genXxY where
132 * 'X' is the generation number and 'Y' is the number of lanes, then this
133 * function returns the corresponding enum usb_ssp_rate.
134 */
usb_get_maximum_ssp_rate(struct device * dev)135 enum usb_ssp_rate usb_get_maximum_ssp_rate(struct device *dev)
136 {
137 const char *maximum_speed;
138 int ret;
139
140 ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
141 if (ret < 0)
142 return USB_SSP_GEN_UNKNOWN;
143
144 ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed);
145 return (ret < 0) ? USB_SSP_GEN_UNKNOWN : ret;
146 }
147 EXPORT_SYMBOL_GPL(usb_get_maximum_ssp_rate);
148
149 /**
150 * usb_state_string - Returns human readable name for the state.
151 * @state: The state to return a human-readable name for. If it's not
152 * any of the states devices in usb_device_state_string enum,
153 * the string UNKNOWN will be returned.
154 */
usb_state_string(enum usb_device_state state)155 const char *usb_state_string(enum usb_device_state state)
156 {
157 static const char *const names[] = {
158 [USB_STATE_NOTATTACHED] = "not attached",
159 [USB_STATE_ATTACHED] = "attached",
160 [USB_STATE_POWERED] = "powered",
161 [USB_STATE_RECONNECTING] = "reconnecting",
162 [USB_STATE_UNAUTHENTICATED] = "unauthenticated",
163 [USB_STATE_DEFAULT] = "default",
164 [USB_STATE_ADDRESS] = "addressed",
165 [USB_STATE_CONFIGURED] = "configured",
166 [USB_STATE_SUSPENDED] = "suspended",
167 };
168
169 if (state < 0 || state >= ARRAY_SIZE(names))
170 return "UNKNOWN";
171
172 return names[state];
173 }
174 EXPORT_SYMBOL_GPL(usb_state_string);
175
176 static const char *const usb_dr_modes[] = {
177 [USB_DR_MODE_UNKNOWN] = "",
178 [USB_DR_MODE_HOST] = "host",
179 [USB_DR_MODE_PERIPHERAL] = "peripheral",
180 [USB_DR_MODE_OTG] = "otg",
181 };
182
usb_get_dr_mode_from_string(const char * str)183 static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str)
184 {
185 int ret;
186
187 ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str);
188 return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret;
189 }
190
usb_get_dr_mode(struct device * dev)191 enum usb_dr_mode usb_get_dr_mode(struct device *dev)
192 {
193 const char *dr_mode;
194 int err;
195
196 err = device_property_read_string(dev, "dr_mode", &dr_mode);
197 if (err < 0)
198 return USB_DR_MODE_UNKNOWN;
199
200 return usb_get_dr_mode_from_string(dr_mode);
201 }
202 EXPORT_SYMBOL_GPL(usb_get_dr_mode);
203
204 /**
205 * usb_get_role_switch_default_mode - Get default mode for given device
206 * @dev: Pointer to the given device
207 *
208 * The function gets string from property 'role-switch-default-mode',
209 * and returns the corresponding enum usb_dr_mode.
210 */
usb_get_role_switch_default_mode(struct device * dev)211 enum usb_dr_mode usb_get_role_switch_default_mode(struct device *dev)
212 {
213 const char *str;
214 int ret;
215
216 ret = device_property_read_string(dev, "role-switch-default-mode", &str);
217 if (ret < 0)
218 return USB_DR_MODE_UNKNOWN;
219
220 return usb_get_dr_mode_from_string(str);
221 }
222 EXPORT_SYMBOL_GPL(usb_get_role_switch_default_mode);
223
224 /**
225 * usb_decode_interval - Decode bInterval into the time expressed in 1us unit
226 * @epd: The descriptor of the endpoint
227 * @speed: The speed that the endpoint works as
228 *
229 * Function returns the interval expressed in 1us unit for servicing
230 * endpoint for data transfers.
231 */
usb_decode_interval(const struct usb_endpoint_descriptor * epd,enum usb_device_speed speed)232 unsigned int usb_decode_interval(const struct usb_endpoint_descriptor *epd,
233 enum usb_device_speed speed)
234 {
235 unsigned int interval = 0;
236
237 switch (usb_endpoint_type(epd)) {
238 case USB_ENDPOINT_XFER_CONTROL:
239 /* uframes per NAK */
240 if (speed == USB_SPEED_HIGH)
241 interval = epd->bInterval;
242 break;
243 case USB_ENDPOINT_XFER_ISOC:
244 interval = 1 << (epd->bInterval - 1);
245 break;
246 case USB_ENDPOINT_XFER_BULK:
247 /* uframes per NAK */
248 if (speed == USB_SPEED_HIGH && usb_endpoint_dir_out(epd))
249 interval = epd->bInterval;
250 break;
251 case USB_ENDPOINT_XFER_INT:
252 if (speed >= USB_SPEED_HIGH)
253 interval = 1 << (epd->bInterval - 1);
254 else
255 interval = epd->bInterval;
256 break;
257 }
258
259 interval *= (speed >= USB_SPEED_HIGH) ? 125 : 1000;
260
261 return interval;
262 }
263 EXPORT_SYMBOL_GPL(usb_decode_interval);
264
265 #ifdef CONFIG_OF
266 /**
267 * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device
268 * which is associated with the given phy device_node
269 * @np: Pointer to the given phy device_node
270 * @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for
271 * phys which do not have phy-cells
272 *
273 * In dts a usb controller associates with phy devices. The function gets
274 * the string from property 'dr_mode' of the controller associated with the
275 * given phy device node, and returns the correspondig enum usb_dr_mode.
276 */
of_usb_get_dr_mode_by_phy(struct device_node * np,int arg0)277 enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0)
278 {
279 struct device_node *controller = NULL;
280 struct of_phandle_args args;
281 const char *dr_mode;
282 int index;
283 int err;
284
285 do {
286 controller = of_find_node_with_property(controller, "phys");
287 if (!of_device_is_available(controller))
288 continue;
289 index = 0;
290 do {
291 if (arg0 == -1) {
292 args.np = of_parse_phandle(controller, "phys",
293 index);
294 args.args_count = 0;
295 } else {
296 err = of_parse_phandle_with_args(controller,
297 "phys", "#phy-cells",
298 index, &args);
299 if (err)
300 break;
301 }
302
303 of_node_put(args.np);
304 if (args.np == np && (args.args_count == 0 ||
305 args.args[0] == arg0))
306 goto finish;
307 index++;
308 } while (args.np);
309 } while (controller);
310
311 finish:
312 err = of_property_read_string(controller, "dr_mode", &dr_mode);
313 of_node_put(controller);
314
315 if (err < 0)
316 return USB_DR_MODE_UNKNOWN;
317
318 return usb_get_dr_mode_from_string(dr_mode);
319 }
320 EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy);
321
322 /**
323 * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
324 * for given targeted hosts (non-PC hosts)
325 * @np: Pointer to the given device_node
326 *
327 * The function gets if the targeted hosts support TPL or not
328 */
of_usb_host_tpl_support(struct device_node * np)329 bool of_usb_host_tpl_support(struct device_node *np)
330 {
331 return of_property_read_bool(np, "tpl-support");
332 }
333 EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);
334
335 /**
336 * of_usb_update_otg_caps - to update usb otg capabilities according to
337 * the passed properties in DT.
338 * @np: Pointer to the given device_node
339 * @otg_caps: Pointer to the target usb_otg_caps to be set
340 *
341 * The function updates the otg capabilities
342 */
of_usb_update_otg_caps(struct device_node * np,struct usb_otg_caps * otg_caps)343 int of_usb_update_otg_caps(struct device_node *np,
344 struct usb_otg_caps *otg_caps)
345 {
346 u32 otg_rev;
347
348 if (!otg_caps)
349 return -EINVAL;
350
351 if (!of_property_read_u32(np, "otg-rev", &otg_rev)) {
352 switch (otg_rev) {
353 case 0x0100:
354 case 0x0120:
355 case 0x0130:
356 case 0x0200:
357 /* Choose the lesser one if it's already been set */
358 if (otg_caps->otg_rev)
359 otg_caps->otg_rev = min_t(u16, otg_rev,
360 otg_caps->otg_rev);
361 else
362 otg_caps->otg_rev = otg_rev;
363 break;
364 default:
365 pr_err("%pOF: unsupported otg-rev: 0x%x\n",
366 np, otg_rev);
367 return -EINVAL;
368 }
369 } else {
370 /*
371 * otg-rev is mandatory for otg properties, if not passed
372 * we set it to be 0 and assume it's a legacy otg device.
373 * Non-dt platform can set it afterwards.
374 */
375 otg_caps->otg_rev = 0;
376 }
377
378 if (of_property_read_bool(np, "hnp-disable"))
379 otg_caps->hnp_support = false;
380 if (of_property_read_bool(np, "srp-disable"))
381 otg_caps->srp_support = false;
382 if (of_property_read_bool(np, "adp-disable") ||
383 (otg_caps->otg_rev < 0x0200))
384 otg_caps->adp_support = false;
385
386 return 0;
387 }
388 EXPORT_SYMBOL_GPL(of_usb_update_otg_caps);
389
390 /**
391 * usb_of_get_companion_dev - Find the companion device
392 * @dev: the device pointer to find a companion
393 *
394 * Find the companion device from platform bus.
395 *
396 * Takes a reference to the returned struct device which needs to be dropped
397 * after use.
398 *
399 * Return: On success, a pointer to the companion device, %NULL on failure.
400 */
usb_of_get_companion_dev(struct device * dev)401 struct device *usb_of_get_companion_dev(struct device *dev)
402 {
403 struct device_node *node;
404 struct platform_device *pdev = NULL;
405
406 node = of_parse_phandle(dev->of_node, "companion", 0);
407 if (node)
408 pdev = of_find_device_by_node(node);
409
410 of_node_put(node);
411
412 return pdev ? &pdev->dev : NULL;
413 }
414 EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);
415 #endif
416
417 struct dentry *usb_debug_root;
418 EXPORT_SYMBOL_GPL(usb_debug_root);
419
usb_common_init(void)420 static int __init usb_common_init(void)
421 {
422 usb_debug_root = debugfs_create_dir("usb", NULL);
423 ledtrig_usb_init();
424 return 0;
425 }
426
usb_common_exit(void)427 static void __exit usb_common_exit(void)
428 {
429 ledtrig_usb_exit();
430 debugfs_remove_recursive(usb_debug_root);
431 }
432
433 subsys_initcall(usb_common_init);
434 module_exit(usb_common_exit);
435
436 MODULE_LICENSE("GPL");
437
