xref: /linux-6.15/include/linux/usb/otg.h (revision 659431fc)
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 /* OTG defines lots of enumeration states before device reset */
13 enum usb_otg_state {
14 	OTG_STATE_UNDEFINED = 0,
15 
16 	/* single-role peripheral, and dual-role default-b */
17 	OTG_STATE_B_IDLE,
18 	OTG_STATE_B_SRP_INIT,
19 	OTG_STATE_B_PERIPHERAL,
20 
21 	/* extra dual-role default-b states */
22 	OTG_STATE_B_WAIT_ACON,
23 	OTG_STATE_B_HOST,
24 
25 	/* dual-role default-a */
26 	OTG_STATE_A_IDLE,
27 	OTG_STATE_A_WAIT_VRISE,
28 	OTG_STATE_A_WAIT_BCON,
29 	OTG_STATE_A_HOST,
30 	OTG_STATE_A_SUSPEND,
31 	OTG_STATE_A_PERIPHERAL,
32 	OTG_STATE_A_WAIT_VFALL,
33 	OTG_STATE_A_VBUS_ERR,
34 };
35 
36 #define USB_OTG_PULLUP_ID		(1 << 0)
37 #define USB_OTG_PULLDOWN_DP		(1 << 1)
38 #define USB_OTG_PULLDOWN_DM		(1 << 2)
39 #define USB_OTG_EXT_VBUS_INDICATOR	(1 << 3)
40 #define USB_OTG_DRV_VBUS		(1 << 4)
41 #define USB_OTG_DRV_VBUS_EXT		(1 << 5)
42 
43 struct otg_transceiver;
44 
45 /* for transceivers connected thru an ULPI interface, the user must
46  * provide access ops
47  */
48 struct otg_io_access_ops {
49 	int (*read)(struct otg_transceiver *otg, u32 reg);
50 	int (*write)(struct otg_transceiver *otg, u32 val, u32 reg);
51 };
52 
53 /*
54  * the otg driver needs to interact with both device side and host side
55  * usb controllers.  it decides which controller is active at a given
56  * moment, using the transceiver, ID signal, HNP and sometimes static
57  * configuration information (including "board isn't wired for otg").
58  */
59 struct otg_transceiver {
60 	struct device		*dev;
61 	const char		*label;
62 	unsigned int		 flags;
63 
64 	u8			default_a;
65 	enum usb_otg_state	state;
66 
67 	struct usb_bus		*host;
68 	struct usb_gadget	*gadget;
69 
70 	struct otg_io_access_ops	*io_ops;
71 	void __iomem			*io_priv;
72 
73 	/* to pass extra port status to the root hub */
74 	u16			port_status;
75 	u16			port_change;
76 
77 	/* initialize/shutdown the OTG controller */
78 	int	(*init)(struct otg_transceiver *otg);
79 	void	(*shutdown)(struct otg_transceiver *otg);
80 
81 	/* bind/unbind the host controller */
82 	int	(*set_host)(struct otg_transceiver *otg,
83 				struct usb_bus *host);
84 
85 	/* bind/unbind the peripheral controller */
86 	int	(*set_peripheral)(struct otg_transceiver *otg,
87 				struct usb_gadget *gadget);
88 
89 	/* effective for B devices, ignored for A-peripheral */
90 	int	(*set_power)(struct otg_transceiver *otg,
91 				unsigned mA);
92 
93 	/* effective for A-peripheral, ignored for B devices */
94 	int	(*set_vbus)(struct otg_transceiver *otg,
95 				bool enabled);
96 
97 	/* for non-OTG B devices: set transceiver into suspend mode */
98 	int	(*set_suspend)(struct otg_transceiver *otg,
99 				int suspend);
100 
101 	/* for B devices only:  start session with A-Host */
102 	int	(*start_srp)(struct otg_transceiver *otg);
103 
104 	/* start or continue HNP role switch */
105 	int	(*start_hnp)(struct otg_transceiver *otg);
106 
107 };
108 
109 
110 /* for board-specific init logic */
111 extern int otg_set_transceiver(struct otg_transceiver *);
112 
113 /* sometimes transceivers are accessed only through e.g. ULPI */
114 extern void usb_nop_xceiv_register(void);
115 extern void usb_nop_xceiv_unregister(void);
116 
117 /* helpers for direct access thru low-level io interface */
118 static inline int otg_io_read(struct otg_transceiver *otg, u32 reg)
119 {
120 	if (otg->io_ops && otg->io_ops->read)
121 		return otg->io_ops->read(otg, reg);
122 
123 	return -EINVAL;
124 }
125 
126 static inline int otg_io_write(struct otg_transceiver *otg, u32 reg, u32 val)
127 {
128 	if (otg->io_ops && otg->io_ops->write)
129 		return otg->io_ops->write(otg, reg, val);
130 
131 	return -EINVAL;
132 }
133 
134 static inline int
135 otg_init(struct otg_transceiver *otg)
136 {
137 	if (otg->init)
138 		return otg->init(otg);
139 
140 	return 0;
141 }
142 
143 static inline void
144 otg_shutdown(struct otg_transceiver *otg)
145 {
146 	if (otg->shutdown)
147 		otg->shutdown(otg);
148 }
149 
150 /* for usb host and peripheral controller drivers */
151 extern struct otg_transceiver *otg_get_transceiver(void);
152 extern void otg_put_transceiver(struct otg_transceiver *);
153 
154 /* Context: can sleep */
155 static inline int
156 otg_start_hnp(struct otg_transceiver *otg)
157 {
158 	return otg->start_hnp(otg);
159 }
160 
161 /* Context: can sleep */
162 static inline int
163 otg_set_vbus(struct otg_transceiver *otg, bool enabled)
164 {
165 	return otg->set_vbus(otg, enabled);
166 }
167 
168 /* for HCDs */
169 static inline int
170 otg_set_host(struct otg_transceiver *otg, struct usb_bus *host)
171 {
172 	return otg->set_host(otg, host);
173 }
174 
175 /* for usb peripheral controller drivers */
176 
177 /* Context: can sleep */
178 static inline int
179 otg_set_peripheral(struct otg_transceiver *otg, struct usb_gadget *periph)
180 {
181 	return otg->set_peripheral(otg, periph);
182 }
183 
184 static inline int
185 otg_set_power(struct otg_transceiver *otg, unsigned mA)
186 {
187 	return otg->set_power(otg, mA);
188 }
189 
190 /* Context: can sleep */
191 static inline int
192 otg_set_suspend(struct otg_transceiver *otg, int suspend)
193 {
194 	if (otg->set_suspend != NULL)
195 		return otg->set_suspend(otg, suspend);
196 	else
197 		return 0;
198 }
199 
200 static inline int
201 otg_start_srp(struct otg_transceiver *otg)
202 {
203 	return otg->start_srp(otg);
204 }
205 
206 
207 /* for OTG controller drivers (and maybe other stuff) */
208 extern int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num);
209 
210 #endif /* __LINUX_USB_OTG_H */
211