xref: /linux-6.15/include/linux/usb/otg.h (revision b898cc70)
1 /* USB OTG (On The Go) defines */
2 /*
3  *
4  * These APIs may be used between USB controllers.  USB device drivers
5  * (for either host or peripheral roles) don't use these calls; they
6  * continue to use just usb_device and usb_gadget.
7  */
8 
9 #ifndef __LINUX_USB_OTG_H
10 #define __LINUX_USB_OTG_H
11 
12 #include <linux/notifier.h>
13 
14 /* OTG defines lots of enumeration states before device reset */
15 enum usb_otg_state {
16 	OTG_STATE_UNDEFINED = 0,
17 
18 	/* single-role peripheral, and dual-role default-b */
19 	OTG_STATE_B_IDLE,
20 	OTG_STATE_B_SRP_INIT,
21 	OTG_STATE_B_PERIPHERAL,
22 
23 	/* extra dual-role default-b states */
24 	OTG_STATE_B_WAIT_ACON,
25 	OTG_STATE_B_HOST,
26 
27 	/* dual-role default-a */
28 	OTG_STATE_A_IDLE,
29 	OTG_STATE_A_WAIT_VRISE,
30 	OTG_STATE_A_WAIT_BCON,
31 	OTG_STATE_A_HOST,
32 	OTG_STATE_A_SUSPEND,
33 	OTG_STATE_A_PERIPHERAL,
34 	OTG_STATE_A_WAIT_VFALL,
35 	OTG_STATE_A_VBUS_ERR,
36 };
37 
38 enum usb_xceiv_events {
39 	USB_EVENT_NONE,         /* no events or cable disconnected */
40 	USB_EVENT_VBUS,         /* vbus valid event */
41 	USB_EVENT_ID,           /* id was grounded */
42 	USB_EVENT_CHARGER,      /* usb dedicated charger */
43 	USB_EVENT_ENUMERATED,   /* gadget driver enumerated */
44 };
45 
46 #define USB_OTG_PULLUP_ID		(1 << 0)
47 #define USB_OTG_PULLDOWN_DP		(1 << 1)
48 #define USB_OTG_PULLDOWN_DM		(1 << 2)
49 #define USB_OTG_EXT_VBUS_INDICATOR	(1 << 3)
50 #define USB_OTG_DRV_VBUS		(1 << 4)
51 #define USB_OTG_DRV_VBUS_EXT		(1 << 5)
52 
53 struct otg_transceiver;
54 
55 /* for transceivers connected thru an ULPI interface, the user must
56  * provide access ops
57  */
58 struct otg_io_access_ops {
59 	int (*read)(struct otg_transceiver *otg, u32 reg);
60 	int (*write)(struct otg_transceiver *otg, u32 val, u32 reg);
61 };
62 
63 /*
64  * the otg driver needs to interact with both device side and host side
65  * usb controllers.  it decides which controller is active at a given
66  * moment, using the transceiver, ID signal, HNP and sometimes static
67  * configuration information (including "board isn't wired for otg").
68  */
69 struct otg_transceiver {
70 	struct device		*dev;
71 	const char		*label;
72 	unsigned int		 flags;
73 
74 	u8			default_a;
75 	enum usb_otg_state	state;
76 
77 	struct usb_bus		*host;
78 	struct usb_gadget	*gadget;
79 
80 	struct otg_io_access_ops	*io_ops;
81 	void __iomem			*io_priv;
82 
83 	/* for notification of usb_xceiv_events */
84 	struct blocking_notifier_head	notifier;
85 
86 	/* to pass extra port status to the root hub */
87 	u16			port_status;
88 	u16			port_change;
89 
90 	/* initialize/shutdown the OTG controller */
91 	int	(*init)(struct otg_transceiver *otg);
92 	void	(*shutdown)(struct otg_transceiver *otg);
93 
94 	/* bind/unbind the host controller */
95 	int	(*set_host)(struct otg_transceiver *otg,
96 				struct usb_bus *host);
97 
98 	/* bind/unbind the peripheral controller */
99 	int	(*set_peripheral)(struct otg_transceiver *otg,
100 				struct usb_gadget *gadget);
101 
102 	/* effective for B devices, ignored for A-peripheral */
103 	int	(*set_power)(struct otg_transceiver *otg,
104 				unsigned mA);
105 
106 	/* effective for A-peripheral, ignored for B devices */
107 	int	(*set_vbus)(struct otg_transceiver *otg,
108 				bool enabled);
109 
110 	/* for non-OTG B devices: set transceiver into suspend mode */
111 	int	(*set_suspend)(struct otg_transceiver *otg,
112 				int suspend);
113 
114 	/* for B devices only:  start session with A-Host */
115 	int	(*start_srp)(struct otg_transceiver *otg);
116 
117 	/* start or continue HNP role switch */
118 	int	(*start_hnp)(struct otg_transceiver *otg);
119 
120 };
121 
122 
123 /* for board-specific init logic */
124 extern int otg_set_transceiver(struct otg_transceiver *);
125 
126 #if defined(CONFIG_NOP_USB_XCEIV) || defined(CONFIG_NOP_USB_XCEIV_MODULE)
127 /* sometimes transceivers are accessed only through e.g. ULPI */
128 extern void usb_nop_xceiv_register(void);
129 extern void usb_nop_xceiv_unregister(void);
130 #else
131 static inline void usb_nop_xceiv_register(void)
132 {
133 }
134 
135 static inline void usb_nop_xceiv_unregister(void)
136 {
137 }
138 #endif
139 
140 /* helpers for direct access thru low-level io interface */
141 static inline int otg_io_read(struct otg_transceiver *otg, u32 reg)
142 {
143 	if (otg->io_ops && otg->io_ops->read)
144 		return otg->io_ops->read(otg, reg);
145 
146 	return -EINVAL;
147 }
148 
149 static inline int otg_io_write(struct otg_transceiver *otg, u32 reg, u32 val)
150 {
151 	if (otg->io_ops && otg->io_ops->write)
152 		return otg->io_ops->write(otg, reg, val);
153 
154 	return -EINVAL;
155 }
156 
157 static inline int
158 otg_init(struct otg_transceiver *otg)
159 {
160 	if (otg->init)
161 		return otg->init(otg);
162 
163 	return 0;
164 }
165 
166 static inline void
167 otg_shutdown(struct otg_transceiver *otg)
168 {
169 	if (otg->shutdown)
170 		otg->shutdown(otg);
171 }
172 
173 /* for usb host and peripheral controller drivers */
174 extern struct otg_transceiver *otg_get_transceiver(void);
175 extern void otg_put_transceiver(struct otg_transceiver *);
176 
177 /* Context: can sleep */
178 static inline int
179 otg_start_hnp(struct otg_transceiver *otg)
180 {
181 	return otg->start_hnp(otg);
182 }
183 
184 /* Context: can sleep */
185 static inline int
186 otg_set_vbus(struct otg_transceiver *otg, bool enabled)
187 {
188 	return otg->set_vbus(otg, enabled);
189 }
190 
191 /* for HCDs */
192 static inline int
193 otg_set_host(struct otg_transceiver *otg, struct usb_bus *host)
194 {
195 	return otg->set_host(otg, host);
196 }
197 
198 /* for usb peripheral controller drivers */
199 
200 /* Context: can sleep */
201 static inline int
202 otg_set_peripheral(struct otg_transceiver *otg, struct usb_gadget *periph)
203 {
204 	return otg->set_peripheral(otg, periph);
205 }
206 
207 static inline int
208 otg_set_power(struct otg_transceiver *otg, unsigned mA)
209 {
210 	return otg->set_power(otg, mA);
211 }
212 
213 /* Context: can sleep */
214 static inline int
215 otg_set_suspend(struct otg_transceiver *otg, int suspend)
216 {
217 	if (otg->set_suspend != NULL)
218 		return otg->set_suspend(otg, suspend);
219 	else
220 		return 0;
221 }
222 
223 static inline int
224 otg_start_srp(struct otg_transceiver *otg)
225 {
226 	return otg->start_srp(otg);
227 }
228 
229 /* notifiers */
230 static inline int
231 otg_register_notifier(struct otg_transceiver *otg, struct notifier_block *nb)
232 {
233 	return blocking_notifier_chain_register(&otg->notifier, nb);
234 }
235 
236 static inline void
237 otg_unregister_notifier(struct otg_transceiver *otg, struct notifier_block *nb)
238 {
239 	blocking_notifier_chain_unregister(&otg->notifier, nb);
240 }
241 
242 /* for OTG controller drivers (and maybe other stuff) */
243 extern int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num);
244 
245 #endif /* __LINUX_USB_OTG_H */
246