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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
22static 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 */
35const 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}
42EXPORT_SYMBOL_GPL(usb_ep_type_string);
43
44/**
45 * usb_otg_state_string() - returns human readable name of OTG state.
46 * @state: the OTG state to return the human readable name of. If it's not
47 * any of the states defined in usb_otg_state enum, 'UNDEFINED' will be
48 * returned.
49 */
50const char *usb_otg_state_string(enum usb_otg_state state)
51{
52 static const char *const names[] = {
53 [OTG_STATE_A_IDLE] = "a_idle",
54 [OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise",
55 [OTG_STATE_A_WAIT_BCON] = "a_wait_bcon",
56 [OTG_STATE_A_HOST] = "a_host",
57 [OTG_STATE_A_SUSPEND] = "a_suspend",
58 [OTG_STATE_A_PERIPHERAL] = "a_peripheral",
59 [OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall",
60 [OTG_STATE_A_VBUS_ERR] = "a_vbus_err",
61 [OTG_STATE_B_IDLE] = "b_idle",
62 [OTG_STATE_B_SRP_INIT] = "b_srp_init",
63 [OTG_STATE_B_PERIPHERAL] = "b_peripheral",
64 [OTG_STATE_B_WAIT_ACON] = "b_wait_acon",
65 [OTG_STATE_B_HOST] = "b_host",
66 };
67
68 if (state < 0 || state >= ARRAY_SIZE(names))
69 return "UNDEFINED";
70
71 return names[state];
72}
73EXPORT_SYMBOL_GPL(usb_otg_state_string);
74
75static const char *const speed_names[] = {
76 [USB_SPEED_UNKNOWN] = "UNKNOWN",
77 [USB_SPEED_LOW] = "low-speed",
78 [USB_SPEED_FULL] = "full-speed",
79 [USB_SPEED_HIGH] = "high-speed",
80 [USB_SPEED_WIRELESS] = "wireless",
81 [USB_SPEED_SUPER] = "super-speed",
82 [USB_SPEED_SUPER_PLUS] = "super-speed-plus",
83};
84
85static const char *const ssp_rate[] = {
86 [USB_SSP_GEN_UNKNOWN] = "UNKNOWN",
87 [USB_SSP_GEN_2x1] = "super-speed-plus-gen2x1",
88 [USB_SSP_GEN_1x2] = "super-speed-plus-gen1x2",
89 [USB_SSP_GEN_2x2] = "super-speed-plus-gen2x2",
90};
91
92/**
93 * usb_speed_string() - Returns human readable-name of the speed.
94 * @speed: The speed to return human-readable name for. If it's not
95 * any of the speeds defined in usb_device_speed enum, string for
96 * USB_SPEED_UNKNOWN will be returned.
97 */
98const char *usb_speed_string(enum usb_device_speed speed)
99{
100 if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
101 speed = USB_SPEED_UNKNOWN;
102 return speed_names[speed];
103}
104EXPORT_SYMBOL_GPL(usb_speed_string);
105
106/**
107 * usb_get_maximum_speed - Get maximum requested speed for a given USB
108 * controller.
109 * @dev: Pointer to the given USB controller device
110 *
111 * The function gets the maximum speed string from property "maximum-speed",
112 * and returns the corresponding enum usb_device_speed.
113 */
114enum usb_device_speed usb_get_maximum_speed(struct device *dev)
115{
116 const char *p = "maximum-speed";
117 int ret;
118
119 ret = device_property_match_property_string(dev, p, ssp_rate, ARRAY_SIZE(ssp_rate));
120 if (ret > 0)
121 return USB_SPEED_SUPER_PLUS;
122
123 ret = device_property_match_property_string(dev, p, speed_names, ARRAY_SIZE(speed_names));
124 if (ret > 0)
125 return ret;
126
127 return USB_SPEED_UNKNOWN;
128}
129EXPORT_SYMBOL_GPL(usb_get_maximum_speed);
130
131/**
132 * usb_get_maximum_ssp_rate - Get the signaling rate generation and lane count
133 * of a SuperSpeed Plus capable device.
134 * @dev: Pointer to the given USB controller device
135 *
136 * If the string from "maximum-speed" property is super-speed-plus-genXxY where
137 * 'X' is the generation number and 'Y' is the number of lanes, then this
138 * function returns the corresponding enum usb_ssp_rate.
139 */
140enum usb_ssp_rate usb_get_maximum_ssp_rate(struct device *dev)
141{
142 const char *maximum_speed;
143 int ret;
144
145 ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
146 if (ret < 0)
147 return USB_SSP_GEN_UNKNOWN;
148
149 ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed);
150 return (ret < 0) ? USB_SSP_GEN_UNKNOWN : ret;
151}
152EXPORT_SYMBOL_GPL(usb_get_maximum_ssp_rate);
153
154/**
155 * usb_state_string - Returns human readable name for the state.
156 * @state: The state to return a human-readable name for. If it's not
157 * any of the states devices in usb_device_state_string enum,
158 * the string UNKNOWN will be returned.
159 */
160const char *usb_state_string(enum usb_device_state state)
161{
162 static const char *const names[] = {
163 [USB_STATE_NOTATTACHED] = "not attached",
164 [USB_STATE_ATTACHED] = "attached",
165 [USB_STATE_POWERED] = "powered",
166 [USB_STATE_RECONNECTING] = "reconnecting",
167 [USB_STATE_UNAUTHENTICATED] = "unauthenticated",
168 [USB_STATE_DEFAULT] = "default",
169 [USB_STATE_ADDRESS] = "addressed",
170 [USB_STATE_CONFIGURED] = "configured",
171 [USB_STATE_SUSPENDED] = "suspended",
172 };
173
174 if (state < 0 || state >= ARRAY_SIZE(names))
175 return "UNKNOWN";
176
177 return names[state];
178}
179EXPORT_SYMBOL_GPL(usb_state_string);
180
181static const char *const usb_dr_modes[] = {
182 [USB_DR_MODE_UNKNOWN] = "",
183 [USB_DR_MODE_HOST] = "host",
184 [USB_DR_MODE_PERIPHERAL] = "peripheral",
185 [USB_DR_MODE_OTG] = "otg",
186};
187
188/**
189 * usb_get_dr_mode_from_string() - Get dual role mode for given string
190 * @str: String to find the corresponding dual role mode for
191 *
192 * This function performs a lookup for the given string and returns the
193 * corresponding enum usb_dr_mode. If no match for the string could be found,
194 * 'USB_DR_MODE_UNKNOWN' is returned.
195 */
196static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str)
197{
198 int ret;
199
200 ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str);
201 return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret;
202}
203
204enum usb_dr_mode usb_get_dr_mode(struct device *dev)
205{
206 const char *dr_mode;
207 int err;
208
209 err = device_property_read_string(dev, "dr_mode", &dr_mode);
210 if (err < 0)
211 return USB_DR_MODE_UNKNOWN;
212
213 return usb_get_dr_mode_from_string(dr_mode);
214}
215EXPORT_SYMBOL_GPL(usb_get_dr_mode);
216
217/**
218 * usb_get_role_switch_default_mode - Get default mode for given device
219 * @dev: Pointer to the given device
220 *
221 * The function gets string from property 'role-switch-default-mode',
222 * and returns the corresponding enum usb_dr_mode.
223 */
224enum usb_dr_mode usb_get_role_switch_default_mode(struct device *dev)
225{
226 const char *str;
227 int ret;
228
229 ret = device_property_read_string(dev, "role-switch-default-mode", &str);
230 if (ret < 0)
231 return USB_DR_MODE_UNKNOWN;
232
233 return usb_get_dr_mode_from_string(str);
234}
235EXPORT_SYMBOL_GPL(usb_get_role_switch_default_mode);
236
237/**
238 * usb_decode_interval - Decode bInterval into the time expressed in 1us unit
239 * @epd: The descriptor of the endpoint
240 * @speed: The speed that the endpoint works as
241 *
242 * Function returns the interval expressed in 1us unit for servicing
243 * endpoint for data transfers.
244 */
245unsigned int usb_decode_interval(const struct usb_endpoint_descriptor *epd,
246 enum usb_device_speed speed)
247{
248 unsigned int interval = 0;
249
250 switch (usb_endpoint_type(epd)) {
251 case USB_ENDPOINT_XFER_CONTROL:
252 /* uframes per NAK */
253 if (speed == USB_SPEED_HIGH)
254 interval = epd->bInterval;
255 break;
256 case USB_ENDPOINT_XFER_ISOC:
257 interval = 1 << (epd->bInterval - 1);
258 break;
259 case USB_ENDPOINT_XFER_BULK:
260 /* uframes per NAK */
261 if (speed == USB_SPEED_HIGH && usb_endpoint_dir_out(epd))
262 interval = epd->bInterval;
263 break;
264 case USB_ENDPOINT_XFER_INT:
265 if (speed >= USB_SPEED_HIGH)
266 interval = 1 << (epd->bInterval - 1);
267 else
268 interval = epd->bInterval;
269 break;
270 }
271
272 interval *= (speed >= USB_SPEED_HIGH) ? 125 : 1000;
273
274 return interval;
275}
276EXPORT_SYMBOL_GPL(usb_decode_interval);
277
278#ifdef CONFIG_OF
279/**
280 * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device
281 * which is associated with the given phy device_node
282 * @np: Pointer to the given phy device_node
283 * @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for
284 * phys which do not have phy-cells
285 *
286 * In dts a usb controller associates with phy devices. The function gets
287 * the string from property 'dr_mode' of the controller associated with the
288 * given phy device node, and returns the correspondig enum usb_dr_mode.
289 */
290enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0)
291{
292 struct device_node *controller;
293 struct of_phandle_args args;
294 const char *dr_mode;
295 int index;
296 int err;
297
298 for_each_node_with_property(controller, "phys") {
299 if (!of_device_is_available(controller))
300 continue;
301 index = 0;
302 do {
303 if (arg0 == -1) {
304 args.np = of_parse_phandle(controller, "phys",
305 index);
306 args.args_count = 0;
307 } else {
308 err = of_parse_phandle_with_args(controller,
309 "phys", "#phy-cells",
310 index, &args);
311 if (err)
312 break;
313 }
314
315 of_node_put(args.np);
316 if (args.np == np && (args.args_count == 0 ||
317 args.args[0] == arg0))
318 goto finish;
319 index++;
320 } while (args.np);
321 }
322
323finish:
324 err = of_property_read_string(controller, "dr_mode", &dr_mode);
325 of_node_put(controller);
326
327 if (err < 0)
328 return USB_DR_MODE_UNKNOWN;
329
330 return usb_get_dr_mode_from_string(dr_mode);
331}
332EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy);
333
334/**
335 * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
336 * for given targeted hosts (non-PC hosts)
337 * @np: Pointer to the given device_node
338 *
339 * The function gets if the targeted hosts support TPL or not
340 */
341bool of_usb_host_tpl_support(struct device_node *np)
342{
343 return of_property_read_bool(np, "tpl-support");
344}
345EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);
346
347/**
348 * of_usb_update_otg_caps - to update usb otg capabilities according to
349 * the passed properties in DT.
350 * @np: Pointer to the given device_node
351 * @otg_caps: Pointer to the target usb_otg_caps to be set
352 *
353 * The function updates the otg capabilities
354 */
355int of_usb_update_otg_caps(struct device_node *np,
356 struct usb_otg_caps *otg_caps)
357{
358 u32 otg_rev;
359
360 if (!otg_caps)
361 return -EINVAL;
362
363 if (!of_property_read_u32(np, "otg-rev", &otg_rev)) {
364 switch (otg_rev) {
365 case 0x0100:
366 case 0x0120:
367 case 0x0130:
368 case 0x0200:
369 /* Choose the lesser one if it's already been set */
370 if (otg_caps->otg_rev)
371 otg_caps->otg_rev = min_t(u16, otg_rev,
372 otg_caps->otg_rev);
373 else
374 otg_caps->otg_rev = otg_rev;
375 break;
376 default:
377 pr_err("%pOF: unsupported otg-rev: 0x%x\n",
378 np, otg_rev);
379 return -EINVAL;
380 }
381 } else {
382 /*
383 * otg-rev is mandatory for otg properties, if not passed
384 * we set it to be 0 and assume it's a legacy otg device.
385 * Non-dt platform can set it afterwards.
386 */
387 otg_caps->otg_rev = 0;
388 }
389
390 if (of_property_read_bool(np, "hnp-disable"))
391 otg_caps->hnp_support = false;
392 if (of_property_read_bool(np, "srp-disable"))
393 otg_caps->srp_support = false;
394 if (of_property_read_bool(np, "adp-disable") ||
395 (otg_caps->otg_rev < 0x0200))
396 otg_caps->adp_support = false;
397
398 return 0;
399}
400EXPORT_SYMBOL_GPL(of_usb_update_otg_caps);
401
402/**
403 * usb_of_get_companion_dev - Find the companion device
404 * @dev: the device pointer to find a companion
405 *
406 * Find the companion device from platform bus.
407 *
408 * Takes a reference to the returned struct device which needs to be dropped
409 * after use.
410 *
411 * Return: On success, a pointer to the companion device, %NULL on failure.
412 */
413struct device *usb_of_get_companion_dev(struct device *dev)
414{
415 struct device_node *node;
416 struct platform_device *pdev = NULL;
417
418 node = of_parse_phandle(dev->of_node, "companion", 0);
419 if (node)
420 pdev = of_find_device_by_node(node);
421
422 of_node_put(node);
423
424 return pdev ? &pdev->dev : NULL;
425}
426EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);
427#endif
428
429struct dentry *usb_debug_root;
430EXPORT_SYMBOL_GPL(usb_debug_root);
431
432DEFINE_MUTEX(usb_dynids_lock);
433EXPORT_SYMBOL_GPL(usb_dynids_lock);
434
435static int __init usb_common_init(void)
436{
437 usb_debug_root = debugfs_create_dir("usb", NULL);
438 ledtrig_usb_init();
439 return 0;
440}
441
442static void __exit usb_common_exit(void)
443{
444 ledtrig_usb_exit();
445 debugfs_remove_recursive(usb_debug_root);
446}
447
448subsys_initcall(usb_common_init);
449module_exit(usb_common_exit);
450
451MODULE_DESCRIPTION("Common code for host and device side USB");
452MODULE_LICENSE("GPL");