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
44const 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}
67EXPORT_SYMBOL_GPL(usb_otg_state_string);
68
69static 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
79static 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 */
92const 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}
98EXPORT_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 */
108enum 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}
124EXPORT_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 */
135enum 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}
147EXPORT_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 */
155const 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}
174EXPORT_SYMBOL_GPL(usb_state_string);
175
176static 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
183static 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
191enum 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}
202EXPORT_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 */
211enum 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}
222EXPORT_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 */
232unsigned 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}
263EXPORT_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 */
277enum 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
311finish:
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}
320EXPORT_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 */
329bool of_usb_host_tpl_support(struct device_node *np)
330{
331	return of_property_read_bool(np, "tpl-support");
332}
333EXPORT_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 */
343int 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}
388EXPORT_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 */
401struct 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}
414EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);
415#endif
416
417struct dentry *usb_debug_root;
418EXPORT_SYMBOL_GPL(usb_debug_root);
419
420static 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
427static void __exit usb_common_exit(void)
428{
429	ledtrig_usb_exit();
430	debugfs_remove_recursive(usb_debug_root);
431}
432
433subsys_initcall(usb_common_init);
434module_exit(usb_common_exit);
435
436MODULE_LICENSE("GPL");
437