1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2007,2008 Freescale Semiconductor, Inc.
4 */
5
6 #ifndef __LINUX_USB_OTG_FSM_H
7 #define __LINUX_USB_OTG_FSM_H
8
9 #include <linux/mutex.h>
10 #include <linux/errno.h>
11
12 #define PROTO_UNDEF (0)
13 #define PROTO_HOST (1)
14 #define PROTO_GADGET (2)
15
16 #define OTG_STS_SELECTOR 0xF000 /* OTG status selector, according to
17 * OTG and EH 2.0 Chapter 6.2.3
18 * Table:6-4
19 */
20
21 #define HOST_REQUEST_FLAG 1 /* Host request flag, according to
22 * OTG and EH 2.0 Charpter 6.2.3
23 * Table:6-5
24 */
25
26 #define T_HOST_REQ_POLL (1500) /* 1500ms, HNP polling interval */
27
28 enum otg_fsm_timer {
29 /* Standard OTG timers */
30 A_WAIT_VRISE,
31 A_WAIT_VFALL,
32 A_WAIT_BCON,
33 A_AIDL_BDIS,
34 B_ASE0_BRST,
35 A_BIDL_ADIS,
36 B_AIDL_BDIS,
37
38 /* Auxiliary timers */
39 B_SE0_SRP,
40 B_SRP_FAIL,
41 A_WAIT_ENUM,
42 B_DATA_PLS,
43 B_SSEND_SRP,
44
45 NUM_OTG_FSM_TIMERS,
46 };
47
48 /**
49 * struct otg_fsm - OTG state machine according to the OTG spec
50 *
51 * OTG hardware Inputs
52 *
53 * Common inputs for A and B device
54 * @id: TRUE for B-device, FALSE for A-device.
55 * @adp_change: TRUE when current ADP measurement (n) value, compared to the
56 * ADP measurement taken at n-2, differs by more than CADP_THR
57 * @power_up: TRUE when the OTG device first powers up its USB system and
58 * ADP measurement taken if ADP capable
59 *
60 * A-Device state inputs
61 * @a_srp_det: TRUE if the A-device detects SRP
62 * @a_vbus_vld: TRUE when VBUS voltage is in regulation
63 * @b_conn: TRUE if the A-device detects connection from the B-device
64 * @a_bus_resume: TRUE when the B-device detects that the A-device is signaling
65 * a resume (K state)
66 * B-Device state inputs
67 * @a_bus_suspend: TRUE when the B-device detects that the A-device has put the
68 * bus into suspend
69 * @a_conn: TRUE if the B-device detects a connection from the A-device
70 * @b_se0_srp: TRUE when the line has been at SE0 for more than the minimum
71 * time before generating SRP
72 * @b_ssend_srp: TRUE when the VBUS has been below VOTG_SESS_VLD for more than
73 * the minimum time before generating SRP
74 * @b_sess_vld: TRUE when the B-device detects that the voltage on VBUS is
75 * above VOTG_SESS_VLD
76 * @test_device: TRUE when the B-device switches to B-Host and detects an OTG
77 * test device. This must be set by host/hub driver
78 *
79 * Application inputs (A-Device)
80 * @a_bus_drop: TRUE when A-device application needs to power down the bus
81 * @a_bus_req: TRUE when A-device application wants to use the bus.
82 * FALSE to suspend the bus
83 *
84 * Application inputs (B-Device)
85 * @b_bus_req: TRUE during the time that the Application running on the
86 * B-device wants to use the bus
87 *
88 * Auxiliary inputs (OTG v1.3 only. Obsolete now.)
89 * @a_sess_vld: TRUE if the A-device detects that VBUS is above VA_SESS_VLD
90 * @b_bus_suspend: TRUE when the A-device detects that the B-device has put
91 * the bus into suspend
92 * @b_bus_resume: TRUE when the A-device detects that the B-device is signaling
93 * resume on the bus
94 *
95 * OTG Output status. Read only for users. Updated by OTG FSM helpers defined
96 * in this file
97 *
98 * Outputs for Both A and B device
99 * @drv_vbus: TRUE when A-device is driving VBUS
100 * @loc_conn: TRUE when the local device has signaled that it is connected
101 * to the bus
102 * @loc_sof: TRUE when the local device is generating activity on the bus
103 * @adp_prb: TRUE when the local device is in the process of doing
104 * ADP probing
105 *
106 * Outputs for B-device state
107 * @adp_sns: TRUE when the B-device is in the process of carrying out
108 * ADP sensing
109 * @data_pulse: TRUE when the B-device is performing data line pulsing
110 *
111 * Internal Variables
112 *
113 * a_set_b_hnp_en: TRUE when the A-device has successfully set the
114 * b_hnp_enable bit in the B-device.
115 * Unused as OTG fsm uses otg->host->b_hnp_enable instead
116 * b_srp_done: TRUE when the B-device has completed initiating SRP
117 * b_hnp_enable: TRUE when the B-device has accepted the
118 * SetFeature(b_hnp_enable) B-device.
119 * Unused as OTG fsm uses otg->gadget->b_hnp_enable instead
120 * a_clr_err: Asserted (by application ?) to clear a_vbus_err due to an
121 * overcurrent condition and causes the A-device to transition
122 * to a_wait_vfall
123 */
124 struct otg_fsm {
125 /* Input */
126 int id;
127 int adp_change;
128 int power_up;
129 int a_srp_det;
130 int a_vbus_vld;
131 int b_conn;
132 int a_bus_resume;
133 int a_bus_suspend;
134 int a_conn;
135 int b_se0_srp;
136 int b_ssend_srp;
137 int b_sess_vld;
138 int test_device;
139 int a_bus_drop;
140 int a_bus_req;
141 int b_bus_req;
142
143 /* Auxiliary inputs */
144 int a_sess_vld;
145 int b_bus_resume;
146 int b_bus_suspend;
147
148 /* Output */
149 int drv_vbus;
150 int loc_conn;
151 int loc_sof;
152 int adp_prb;
153 int adp_sns;
154 int data_pulse;
155
156 /* Internal variables */
157 int a_set_b_hnp_en;
158 int b_srp_done;
159 int b_hnp_enable;
160 int a_clr_err;
161
162 /* Informative variables. All unused as of now */
163 int a_bus_drop_inf;
164 int a_bus_req_inf;
165 int a_clr_err_inf;
166 int b_bus_req_inf;
167 /* Auxiliary informative variables */
168 int a_suspend_req_inf;
169
170 /* Timeout indicator for timers */
171 int a_wait_vrise_tmout;
172 int a_wait_vfall_tmout;
173 int a_wait_bcon_tmout;
174 int a_aidl_bdis_tmout;
175 int b_ase0_brst_tmout;
176 int a_bidl_adis_tmout;
177
178 struct otg_fsm_ops *ops;
179 struct usb_otg *otg;
180
181 /* Current usb protocol used: 0:undefine; 1:host; 2:client */
182 int protocol;
183 struct mutex lock;
184 u8 *host_req_flag;
185 struct delayed_work hnp_polling_work;
186 bool hnp_work_inited;
187 bool state_changed;
188 };
189
190 struct otg_fsm_ops {
191 void (*chrg_vbus)(struct otg_fsm *fsm, int on);
192 void (*drv_vbus)(struct otg_fsm *fsm, int on);
193 void (*loc_conn)(struct otg_fsm *fsm, int on);
194 void (*loc_sof)(struct otg_fsm *fsm, int on);
195 void (*start_pulse)(struct otg_fsm *fsm);
196 void (*start_adp_prb)(struct otg_fsm *fsm);
197 void (*start_adp_sns)(struct otg_fsm *fsm);
198 void (*add_timer)(struct otg_fsm *fsm, enum otg_fsm_timer timer);
199 void (*del_timer)(struct otg_fsm *fsm, enum otg_fsm_timer timer);
200 int (*start_host)(struct otg_fsm *fsm, int on);
201 int (*start_gadget)(struct otg_fsm *fsm, int on);
202 };
203
204
205 static inline int otg_chrg_vbus(struct otg_fsm *fsm, int on)
206 {
207 if (!fsm->ops->chrg_vbus)
208 return -EOPNOTSUPP;
209 fsm->ops->chrg_vbus(fsm, on);
210 return 0;
211 }
212
213 static inline int otg_drv_vbus(struct otg_fsm *fsm, int on)
214 {
215 if (!fsm->ops->drv_vbus)
216 return -EOPNOTSUPP;
217 if (fsm->drv_vbus != on) {
218 fsm->drv_vbus = on;
219 fsm->ops->drv_vbus(fsm, on);
220 }
221 return 0;
222 }
223
224 static inline int otg_loc_conn(struct otg_fsm *fsm, int on)
225 {
226 if (!fsm->ops->loc_conn)
227 return -EOPNOTSUPP;
228 if (fsm->loc_conn != on) {
229 fsm->loc_conn = on;
230 fsm->ops->loc_conn(fsm, on);
231 }
232 return 0;
233 }
234
235 static inline int otg_loc_sof(struct otg_fsm *fsm, int on)
236 {
237 if (!fsm->ops->loc_sof)
238 return -EOPNOTSUPP;
239 if (fsm->loc_sof != on) {
240 fsm->loc_sof = on;
241 fsm->ops->loc_sof(fsm, on);
242 }
243 return 0;
244 }
245
246 static inline int otg_start_pulse(struct otg_fsm *fsm)
247 {
248 if (!fsm->ops->start_pulse)
249 return -EOPNOTSUPP;
250 if (!fsm->data_pulse) {
251 fsm->data_pulse = 1;
252 fsm->ops->start_pulse(fsm);
253 }
254 return 0;
255 }
256
257 static inline int otg_start_adp_prb(struct otg_fsm *fsm)
258 {
259 if (!fsm->ops->start_adp_prb)
260 return -EOPNOTSUPP;
261 if (!fsm->adp_prb) {
262 fsm->adp_sns = 0;
263 fsm->adp_prb = 1;
264 fsm->ops->start_adp_prb(fsm);
265 }
266 return 0;
267 }
268
269 static inline int otg_start_adp_sns(struct otg_fsm *fsm)
270 {
271 if (!fsm->ops->start_adp_sns)
272 return -EOPNOTSUPP;
273 if (!fsm->adp_sns) {
274 fsm->adp_sns = 1;
275 fsm->ops->start_adp_sns(fsm);
276 }
277 return 0;
278 }
279
280 static inline int otg_add_timer(struct otg_fsm *fsm, enum otg_fsm_timer timer)
281 {
282 if (!fsm->ops->add_timer)
283 return -EOPNOTSUPP;
284 fsm->ops->add_timer(fsm, timer);
285 return 0;
286 }
287
288 static inline int otg_del_timer(struct otg_fsm *fsm, enum otg_fsm_timer timer)
289 {
290 if (!fsm->ops->del_timer)
291 return -EOPNOTSUPP;
292 fsm->ops->del_timer(fsm, timer);
293 return 0;
294 }
295
296 static inline int otg_start_host(struct otg_fsm *fsm, int on)
297 {
298 if (!fsm->ops->start_host)
299 return -EOPNOTSUPP;
300 return fsm->ops->start_host(fsm, on);
301 }
302
303 static inline int otg_start_gadget(struct otg_fsm *fsm, int on)
304 {
305 if (!fsm->ops->start_gadget)
306 return -EOPNOTSUPP;
307 return fsm->ops->start_gadget(fsm, on);
308 }
309
310 int otg_statemachine(struct otg_fsm *fsm);
311
312 #endif /* __LINUX_USB_OTG_FSM_H */
313
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