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/usb/ch9.h>
15 #include <linux/usb/of.h>
16 #include <linux/usb/otg.h>
17 #include <linux/of_platform.h>
18 #include <linux/debugfs.h>
19 #include "common.h"
20
21 static const char *const ep_type_names[] = {
22 [USB_ENDPOINT_XFER_CONTROL] = "ctrl",
23 [USB_ENDPOINT_XFER_ISOC] = "isoc",
24 [USB_ENDPOINT_XFER_BULK] = "bulk",
25 [USB_ENDPOINT_XFER_INT] = "intr",
26 };
27
usb_ep_type_string(int ep_type)28 const char *usb_ep_type_string(int ep_type)
29 {
30 if (ep_type < 0 || ep_type >= ARRAY_SIZE(ep_type_names))
31 return "unknown";
32
33 return ep_type_names[ep_type];
34 }
35 EXPORT_SYMBOL_GPL(usb_ep_type_string);
36
usb_otg_state_string(enum usb_otg_state state)37 const char *usb_otg_state_string(enum usb_otg_state state)
38 {
39 static const char *const names[] = {
40 [OTG_STATE_A_IDLE] = "a_idle",
41 [OTG_STATE_A_WAIT_VRISE] = "a_wait_vrise",
42 [OTG_STATE_A_WAIT_BCON] = "a_wait_bcon",
43 [OTG_STATE_A_HOST] = "a_host",
44 [OTG_STATE_A_SUSPEND] = "a_suspend",
45 [OTG_STATE_A_PERIPHERAL] = "a_peripheral",
46 [OTG_STATE_A_WAIT_VFALL] = "a_wait_vfall",
47 [OTG_STATE_A_VBUS_ERR] = "a_vbus_err",
48 [OTG_STATE_B_IDLE] = "b_idle",
49 [OTG_STATE_B_SRP_INIT] = "b_srp_init",
50 [OTG_STATE_B_PERIPHERAL] = "b_peripheral",
51 [OTG_STATE_B_WAIT_ACON] = "b_wait_acon",
52 [OTG_STATE_B_HOST] = "b_host",
53 };
54
55 if (state < 0 || state >= ARRAY_SIZE(names))
56 return "UNDEFINED";
57
58 return names[state];
59 }
60 EXPORT_SYMBOL_GPL(usb_otg_state_string);
61
62 static const char *const speed_names[] = {
63 [USB_SPEED_UNKNOWN] = "UNKNOWN",
64 [USB_SPEED_LOW] = "low-speed",
65 [USB_SPEED_FULL] = "full-speed",
66 [USB_SPEED_HIGH] = "high-speed",
67 [USB_SPEED_WIRELESS] = "wireless",
68 [USB_SPEED_SUPER] = "super-speed",
69 [USB_SPEED_SUPER_PLUS] = "super-speed-plus",
70 };
71
usb_speed_string(enum usb_device_speed speed)72 const char *usb_speed_string(enum usb_device_speed speed)
73 {
74 if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
75 speed = USB_SPEED_UNKNOWN;
76 return speed_names[speed];
77 }
78 EXPORT_SYMBOL_GPL(usb_speed_string);
79
usb_get_maximum_speed(struct device * dev)80 enum usb_device_speed usb_get_maximum_speed(struct device *dev)
81 {
82 const char *maximum_speed;
83 int ret;
84
85 ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
86 if (ret < 0)
87 return USB_SPEED_UNKNOWN;
88
89 ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed);
90
91 return (ret < 0) ? USB_SPEED_UNKNOWN : ret;
92 }
93 EXPORT_SYMBOL_GPL(usb_get_maximum_speed);
94
usb_state_string(enum usb_device_state state)95 const char *usb_state_string(enum usb_device_state state)
96 {
97 static const char *const names[] = {
98 [USB_STATE_NOTATTACHED] = "not attached",
99 [USB_STATE_ATTACHED] = "attached",
100 [USB_STATE_POWERED] = "powered",
101 [USB_STATE_RECONNECTING] = "reconnecting",
102 [USB_STATE_UNAUTHENTICATED] = "unauthenticated",
103 [USB_STATE_DEFAULT] = "default",
104 [USB_STATE_ADDRESS] = "addressed",
105 [USB_STATE_CONFIGURED] = "configured",
106 [USB_STATE_SUSPENDED] = "suspended",
107 };
108
109 if (state < 0 || state >= ARRAY_SIZE(names))
110 return "UNKNOWN";
111
112 return names[state];
113 }
114 EXPORT_SYMBOL_GPL(usb_state_string);
115
116 static const char *const usb_dr_modes[] = {
117 [USB_DR_MODE_UNKNOWN] = "",
118 [USB_DR_MODE_HOST] = "host",
119 [USB_DR_MODE_PERIPHERAL] = "peripheral",
120 [USB_DR_MODE_OTG] = "otg",
121 };
122
usb_get_dr_mode_from_string(const char * str)123 static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str)
124 {
125 int ret;
126
127 ret = match_string(usb_dr_modes, ARRAY_SIZE(usb_dr_modes), str);
128 return (ret < 0) ? USB_DR_MODE_UNKNOWN : ret;
129 }
130
usb_get_dr_mode(struct device * dev)131 enum usb_dr_mode usb_get_dr_mode(struct device *dev)
132 {
133 const char *dr_mode;
134 int err;
135
136 err = device_property_read_string(dev, "dr_mode", &dr_mode);
137 if (err < 0)
138 return USB_DR_MODE_UNKNOWN;
139
140 return usb_get_dr_mode_from_string(dr_mode);
141 }
142 EXPORT_SYMBOL_GPL(usb_get_dr_mode);
143
144 #ifdef CONFIG_OF
145 /**
146 * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device
147 * which is associated with the given phy device_node
148 * @np: Pointer to the given phy device_node
149 * @arg0: phandle args[0] for phy's with #phy-cells >= 1, or -1 for
150 * phys which do not have phy-cells
151 *
152 * In dts a usb controller associates with phy devices. The function gets
153 * the string from property 'dr_mode' of the controller associated with the
154 * given phy device node, and returns the correspondig enum usb_dr_mode.
155 */
of_usb_get_dr_mode_by_phy(struct device_node * np,int arg0)156 enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *np, int arg0)
157 {
158 struct device_node *controller = NULL;
159 struct of_phandle_args args;
160 const char *dr_mode;
161 int index;
162 int err;
163
164 do {
165 controller = of_find_node_with_property(controller, "phys");
166 if (!of_device_is_available(controller))
167 continue;
168 index = 0;
169 do {
170 if (arg0 == -1) {
171 args.np = of_parse_phandle(controller, "phys",
172 index);
173 args.args_count = 0;
174 } else {
175 err = of_parse_phandle_with_args(controller,
176 "phys", "#phy-cells",
177 index, &args);
178 if (err)
179 break;
180 }
181
182 of_node_put(args.np);
183 if (args.np == np && (args.args_count == 0 ||
184 args.args[0] == arg0))
185 goto finish;
186 index++;
187 } while (args.np);
188 } while (controller);
189
190 finish:
191 err = of_property_read_string(controller, "dr_mode", &dr_mode);
192 of_node_put(controller);
193
194 if (err < 0)
195 return USB_DR_MODE_UNKNOWN;
196
197 return usb_get_dr_mode_from_string(dr_mode);
198 }
199 EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy);
200
201 /**
202 * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
203 * for given targeted hosts (non-PC hosts)
204 * @np: Pointer to the given device_node
205 *
206 * The function gets if the targeted hosts support TPL or not
207 */
of_usb_host_tpl_support(struct device_node * np)208 bool of_usb_host_tpl_support(struct device_node *np)
209 {
210 return of_property_read_bool(np, "tpl-support");
211 }
212 EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);
213
214 /**
215 * of_usb_update_otg_caps - to update usb otg capabilities according to
216 * the passed properties in DT.
217 * @np: Pointer to the given device_node
218 * @otg_caps: Pointer to the target usb_otg_caps to be set
219 *
220 * The function updates the otg capabilities
221 */
of_usb_update_otg_caps(struct device_node * np,struct usb_otg_caps * otg_caps)222 int of_usb_update_otg_caps(struct device_node *np,
223 struct usb_otg_caps *otg_caps)
224 {
225 u32 otg_rev;
226
227 if (!otg_caps)
228 return -EINVAL;
229
230 if (!of_property_read_u32(np, "otg-rev", &otg_rev)) {
231 switch (otg_rev) {
232 case 0x0100:
233 case 0x0120:
234 case 0x0130:
235 case 0x0200:
236 /* Choose the lesser one if it's already been set */
237 if (otg_caps->otg_rev)
238 otg_caps->otg_rev = min_t(u16, otg_rev,
239 otg_caps->otg_rev);
240 else
241 otg_caps->otg_rev = otg_rev;
242 break;
243 default:
244 pr_err("%pOF: unsupported otg-rev: 0x%x\n",
245 np, otg_rev);
246 return -EINVAL;
247 }
248 } else {
249 /*
250 * otg-rev is mandatory for otg properties, if not passed
251 * we set it to be 0 and assume it's a legacy otg device.
252 * Non-dt platform can set it afterwards.
253 */
254 otg_caps->otg_rev = 0;
255 }
256
257 if (of_property_read_bool(np, "hnp-disable"))
258 otg_caps->hnp_support = false;
259 if (of_property_read_bool(np, "srp-disable"))
260 otg_caps->srp_support = false;
261 if (of_property_read_bool(np, "adp-disable") ||
262 (otg_caps->otg_rev < 0x0200))
263 otg_caps->adp_support = false;
264
265 return 0;
266 }
267 EXPORT_SYMBOL_GPL(of_usb_update_otg_caps);
268
269 /**
270 * usb_of_get_companion_dev - Find the companion device
271 * @dev: the device pointer to find a companion
272 *
273 * Find the companion device from platform bus.
274 *
275 * Takes a reference to the returned struct device which needs to be dropped
276 * after use.
277 *
278 * Return: On success, a pointer to the companion device, %NULL on failure.
279 */
usb_of_get_companion_dev(struct device * dev)280 struct device *usb_of_get_companion_dev(struct device *dev)
281 {
282 struct device_node *node;
283 struct platform_device *pdev = NULL;
284
285 node = of_parse_phandle(dev->of_node, "companion", 0);
286 if (node)
287 pdev = of_find_device_by_node(node);
288
289 of_node_put(node);
290
291 return pdev ? &pdev->dev : NULL;
292 }
293 EXPORT_SYMBOL_GPL(usb_of_get_companion_dev);
294 #endif
295
296 struct dentry *usb_debug_root;
297 EXPORT_SYMBOL_GPL(usb_debug_root);
298
usb_common_init(void)299 static int __init usb_common_init(void)
300 {
301 usb_debug_root = debugfs_create_dir("usb", NULL);
302 ledtrig_usb_init();
303 return 0;
304 }
305
usb_common_exit(void)306 static void __exit usb_common_exit(void)
307 {
308 ledtrig_usb_exit();
309 debugfs_remove_recursive(usb_debug_root);
310 }
311
312 subsys_initcall(usb_common_init);
313 module_exit(usb_common_exit);
314
315 MODULE_LICENSE("GPL");
316
