summaryrefslogtreecommitdiff
path: root/drivers/usb/common/common.c
blob: 347fb3d3894a5c746ab15f1280aa345b352bfbec (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
// SPDX-License-Identifier: GPL-2.0
/*
 * Provides code common for host and device side USB.
 *
 * If either host side (ie. CONFIG_USB=y) or device side USB stack
 * (ie. CONFIG_USB_GADGET=y) is compiled in the kernel, this module is
 * compiled-in as well.  Otherwise, if either of the two stacks is
 * compiled as module, this file is compiled as module as well.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/usb/ch9.h>
#include <linux/usb/of.h>
#include <linux/usb/otg.h>
#include <linux/of_platform.h>
#include <linux/debugfs.h>
#include "common.h"

static const char *const ep_type_names[] = {
	[USB_ENDPOINT_XFER_CONTROL] = "ctrl",
	[USB_ENDPOINT_XFER_ISOC] = "isoc",
	[USB_ENDPOINT_XFER_BULK] = "bulk",
	[USB_ENDPOINT_XFER_INT] = "intr",
};

/**
 * usb_ep_type_string() - Returns human readable-name of the endpoint type.
 * @ep_type: The endpoint type to return human-readable name for.  If it's not
 *   any of the types: USB_ENDPOINT_XFER_{CONTROL, ISOC, BULK, INT},
 *   usually got by usb_endpoint_type(), the string 'unknown' will be returned.
 */
const char *usb_ep_type_string(int ep_type)
{
	if (ep_type < 0 || ep_type >= ARRAY_SIZE(ep_type_names))
		return "unknown";

	return ep_type_names[ep_type];
}
EXPORT_SYMBOL_GPL(usb_ep_type_string);

const char *usb_otg_state_string(enum usb_otg_state state)
{
	static const char *const names[] = {
		[OTG_STATE_A_IDLE] = "a_idle",
		[OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise",
		[OTG_STATE_A_WAIT_BCON] = "a_wait_bcon",
		[OTG_STATE_A_HOST] = "a_host",
		[OTG_STATE_A_SUSPEND] = "a_suspend",
		[OTG_STATE_A_PERIPHERAL] = "a_peripheral",
		[OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall",
		[OTG_STATE_A_VBUS_ERR] = "a_vbus_err",
		[OTG_STATE_B_IDLE] = "b_idle",
		[OTG_STATE_B_SRP_INIT] = "b_srp_init",
		[OTG_STATE_B_PERIPHERAL] = "b_peripheral",
		[OTG_STATE_B_WAIT_ACON] = "b_wait_acon",
		[OTG_STATE_B_HOST] = "b_host",
	};

	if (state < 0 || state >= ARRAY_SIZE(names))
		return "UNDEFINED";

	return names[state];
}
EXPORT_SYMBOL_GPL(usb_otg_state_string);

static const char *const speed_names[] = {
	[USB_SPEED_UNKNOWN] = "UNKNOWN",
	[USB_SPEED_LOW] = "low-speed",
	[USB_SPEED_FULL] = "full-speed",
	[USB_SPEED_HIGH] = "high-speed",
	[USB_SPEED_WIRELESS] = "wireless",
	[USB_SPEED_SUPER] = "super-speed",
	[USB_SPEED_SUPER_PLUS] = "super-speed-plus",
};

static const char *const ssp_rate[] = {
	[USB_SSP_GEN_UNKNOWN] = "UNKNOWN",
	[USB_SSP_GEN_2x1] = "super-speed-plus-gen2x1",
	[USB_SSP_GEN_1x2] = "super-speed-plus-gen1x2",
	[USB_SSP_GEN_2x2] = "super-speed-plus-gen2x2",
};

/**
 * usb_speed_string() - Returns human readable-name of the speed.
 * @speed: The speed to return human-readable name for.  If it's not
 *   any of the speeds defined in usb_device_speed enum, string for
 *   USB_SPEED_UNKNOWN will be returned.
 */
const char *usb_speed_string(enum usb_device_speed speed)
{
	if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
		speed = USB_SPEED_UNKNOWN;
	return speed_names[speed];
}
EXPORT_SYMBOL_GPL(usb_speed_string);

/**
 * usb_get_maximum_speed - Get maximum requested speed for a given USB
 * controller.
 * @dev: Pointer to the given USB controller device
 *
 * The function gets the maximum speed string from property "maximum-speed",
 * and returns the corresponding enum usb_device_speed.
 */
enum usb_device_speed usb_get_maximum_speed(struct device *dev)
{
	const char *maximum_speed;
	int ret;

	ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
	if (ret < 0)
		return USB_SPEED_UNKNOWN;

	ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed);
	if (ret > 0)
		return USB_SPEED_SUPER_PLUS;

	ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed);
	return (ret < 0) ? USB_SPEED_UNKNOWN : ret;
}
EXPORT_SYMBOL_GPL(usb_get_maximum_speed);

/**
 * usb_get_maximum_ssp_rate - Get the signaling rate generation and lane count
 *	of a SuperSpeed Plus capable device.
 * @dev: Pointer to the given USB controller device
 *
 * If the string from "maximum-speed" property is super-speed-plus-genXxY where
 * 'X' is the generation number and 'Y' is the number of lanes, then this
 * function returns the corresponding enum usb_ssp_rate.
 */
enum usb_ssp_rate usb_get_maximum_ssp_rate(struct device *dev)
{
	const char *maximum_speed;
	int ret;

	ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
	if (ret < 0)
		return USB_SSP_GEN_UNKNOWN;

	ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed);
	return (ret < 0) ? USB_SSP_GEN_UNKNOWN : ret;
}
EXPORT_SYMBOL_GPL(usb_get_maximum_ssp_rate);

/**
 * usb_state_string - Returns human readable name for the state.
 * @state: The state to return a human-readable name for. If it's not
 *	any of the states devices in usb_device_state_string enum,
 *	the string UNKNOWN will be returned.
 */
const char *usb_state_string(enum usb_device_state state)
{
	static const char *const names[] = {
		[USB_STATE_NOTATTACHED] = "not attached",
		[USB_STATE_ATTACHED] = "attached",
		[USB_STATE_POWERED] = "powered",
		[USB_STATE_RECONNECTING] = "reconnecting",
		[USB_STATE_UNAUTHENTICATED] = "unauthenticated",
		[USB_STATE_DEFAULT] = "default",
		[USB_STATE_ADDRESS] = "addressed",
		[USB_STATE_CONFIGURED] = "configured",
		[USB_STATE_SUSPENDED] = "suspended",
	};

	if (state < 0 || state >= ARRAY_SIZE(names))
		return "UNKNOWN";

	return names[state];
}
EXPORT_SYMBOL_GPL(usb_state_string);

static const char *const usb_dr_modes[] = {
	[USB_DR_MODE_UNKNOWN]		= "",
	[USB_DR_MODE_HOST]		= "host",
	[USB_DR_MODE_PERIPHERAL]	= "peripheral",
	[USB_DR_MODE_OTG]		= "otg",
};

static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str)
{
	int ret;

	ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str);
	return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret;
}

enum usb_dr_mode usb_get_dr_mode(struct device *dev)
{
	const char *dr_mode;
	int err;

	err = device_property_read_string(dev, "dr_mode", &dr_mode);
	if (err < 0)
		return USB_DR_MODE_UNKNOWN;

	return usb_get_dr_mode_from_string(dr_mode);
}
EXPORT_SYMBOL_GPL(usb_get_dr_mode);

/**
 * usb_decode_interval - Decode bInterval into the time expressed in 1us unit
 * @epd: The descriptor of the endpoint
 * @speed: The speed that the endpoint works as
 *
 * Function returns the interval expressed in 1us unit for servicing
 * endpoint for data transfers.
 */
unsigned int usb_decode_interval(const struct usb_endpoint_descriptor *epd,
				 enum usb_device_speed speed)
{
	unsigned int interval = 0;

	switch (usb_endpoint_type(epd)) {
	case USB_ENDPOINT_XFER_CONTROL:
		/* uframes per NAK */
		if (speed == USB_SPEED_HIGH)
			interval = epd->bInterval;
		break;
	case USB_ENDPOINT_XFER_ISOC:
		interval = 1 << (epd->bInterval - 1);
		break;
	case USB_ENDPOINT_XFER_BULK:
		/* uframes per NAK */
		if (speed == USB_SPEED_HIGH && usb_endpoint_dir_out(epd))
			interval = epd->bInterval;
		break;
	case USB_ENDPOINT_XFER_INT:
		if (speed >= USB_SPEED_HIGH)
			interval = 1 << (epd->bInterval - 1);
		else
			interval = epd->bInterval;
		break;
	}

	interval *= (speed >= USB_SPEED_HIGH) ? 125 : 1000;

	return interval;
}
EXPORT_SYMBOL_GPL(usb_decode_interval);

#ifdef CONFIG_OF
/**
 * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device
 * which is associated with the given phy device_node
 * @np:	Pointer to the given phy device_node
 * @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for
 *        phys which do not have phy-cells
 *
 * In dts a usb controller associates with phy devices.  The function gets
 * the string from property 'dr_mode' of the controller associated with the
 * given phy device node, and returns the correspondig enum usb_dr_mode.
 */
enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0)
{
	struct device_node *controller = NULL;
	struct of_phandle_args args;
	const char *dr_mode;
	int index;
	int err;

	do {
		controller = of_find_node_with_property(controller, "phys");
		if (!of_device_is_available(controller))
			continue;
		index = 0;
		do {
			if (arg0 == -1) {
				args.np = of_parse_phandle(controller, "phys",
							index);
				args.args_count = 0;
			} else {
				err = of_parse_phandle_with_args(controller,
							"phys", "#phy-cells",
							index, &args);
				if (err)
					break;
			}

			of_node_put(args.np);
			if (args.np == np && (args.args_count == 0 ||
					      args.args[0] == arg0))
				goto finish;
			index++;
		} while (args.np);
	} while (controller);

finish:
	err = of_property_read_string(controller, "dr_mode", &dr_mode);
	of_node_put(controller);

	if (err < 0)
		return USB_DR_MODE_UNKNOWN;

	return usb_get_dr_mode_from_string(dr_mode);
}
EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy);

/**
 * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
 * for given targeted hosts (non-PC hosts)
 * @np: Pointer to the given device_node
 *
 * The function gets if the targeted hosts support TPL or not
 */
bool of_usb_host_tpl_support(struct device_node *np)
{
	return of_property_read_bool(np, "tpl-support");
}
EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);

/**
 * of_usb_update_otg_caps - to update usb otg capabilities according to
 * the passed properties in DT.
 * @np: Pointer to the given device_node
 * @otg_caps: Pointer to the target usb_otg_caps to be set
 *
 * The function updates the otg capabilities
 */
int of_usb_update_otg_caps(struct device_node *np,
			struct usb_otg_caps *otg_caps)
{
	u32 otg_rev;

	if (!otg_caps)
		return -EINVAL;

	if (!of_property_read_u32(np, "otg-rev", &otg_rev)) {
		switch (otg_rev) {
		case 0x0100:
		case 0x0120:
		case 0x0130:
		case 0x0200:
			/* Choose the lesser one if it's already been set */
			if (otg_caps->otg_rev)
				otg_caps->otg_rev = min_t(u16, otg_rev,
							otg_caps->otg_rev);
			else
				otg_caps->otg_rev = otg_rev;
			break;
		default:
			pr_err("%pOF: unsupported otg-rev: 0x%x\n",
						np, otg_rev);
			return -EINVAL;
		}
	} else {
		/*
		 * otg-rev is mandatory for otg properties, if not passed
		 * we set it to be 0 and assume it's a legacy otg device.
		 * Non-dt platform can set it afterwards.
		 */
		otg_caps->otg_rev = 0;
	}

	if (of_property_read_bool(np, "hnp-disable"))
		otg_caps->hnp_support = false;
	if (of_property_read_bool(np, "srp-disable"))
		otg_caps->srp_support = false;
	if (of_property_read_bool(np, "adp-disable") ||
				(otg_caps->otg_rev < 0x0200))
		otg_caps->adp_support = false;

	return 0;
}
EXPORT_SYMBOL_GPL(of_usb_update_otg_caps);

/**
 * usb_of_get_companion_dev - Find the companion device
 * @dev: the device pointer to find a companion
 *
 * Find the companion device from platform bus.
 *
 * Takes a reference to the returned struct device which needs to be dropped
 * after use.
 *
 * Return: On success, a pointer to the companion device, %NULL on failure.
 */
struct device *usb_of_get_companion_dev(struct device *dev)
{
	struct device_node *node;
	struct platform_device *pdev = NULL;

	node = of_parse_phandle(dev->of_node, "companion", 0);
	if (node)
		pdev = of_find_device_by_node(node);

	of_node_put(node);

	return pdev ? &pdev->dev : NULL;
}
EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);
#endif

struct dentry *usb_debug_root;
EXPORT_SYMBOL_GPL(usb_debug_root);

static int __init usb_common_init(void)
{
	usb_debug_root = debugfs_create_dir("usb", NULL);
	ledtrig_usb_init();
	return 0;
}

static void __exit usb_common_exit(void)
{
	ledtrig_usb_exit();
	debugfs_remove_recursive(usb_debug_root);
}

subsys_initcall(usb_common_init);
module_exit(usb_common_exit);

MODULE_LICENSE("GPL");