1 // SPDX-License-Identifier: GPL-2.0+
2 /* Copyright (C) 2007,2008 Freescale Semiconductor, Inc.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by the
6 * Free Software Foundation; either version 2 of the License, or (at your
7 * option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 675 Mass Ave, Cambridge, MA 02139, USA.
17 */
18
19 #ifndef __LINUX_USB_OTG_FSM_H
20 #define __LINUX_USB_OTG_FSM_H
21
22 #include <linux/mutex.h>
23 #include <linux/errno.h>
24
25 #define PROTO_UNDEF (0)
26 #define PROTO_HOST (1)
27 #define PROTO_GADGET (2)
28
29 #define OTG_STS_SELECTOR 0xF000 /* OTG status selector, according to
30 * OTG and EH 2.0 Chapter 6.2.3
31 * Table:6-4
32 */
33
34 #define HOST_REQUEST_FLAG 1 /* Host request flag, according to
35 * OTG and EH 2.0 Charpter 6.2.3
36 * Table:6-5
37 */
38
39 #define T_HOST_REQ_POLL (1500) /* 1500ms, HNP polling interval */
40
41 enum otg_fsm_timer {
42 /* Standard OTG timers */
43 A_WAIT_VRISE,
44 A_WAIT_VFALL,
45 A_WAIT_BCON,
46 A_AIDL_BDIS,
47 B_ASE0_BRST,
48 A_BIDL_ADIS,
49 B_AIDL_BDIS,
50
51 /* Auxiliary timers */
52 B_SE0_SRP,
53 B_SRP_FAIL,
54 A_WAIT_ENUM,
55 B_DATA_PLS,
56 B_SSEND_SRP,
57
58 NUM_OTG_FSM_TIMERS,
59 };
60
61 /**
62 * struct otg_fsm - OTG state machine according to the OTG spec
63 *
64 * OTG hardware Inputs
65 *
66 * Common inputs for A and B device
67 * @id: TRUE for B-device, FALSE for A-device.
68 * @adp_change: TRUE when current ADP measurement (n) value, compared to the
69 * ADP measurement taken at n-2, differs by more than CADP_THR
70 * @power_up: TRUE when the OTG device first powers up its USB system and
71 * ADP measurement taken if ADP capable
72 *
73 * A-Device state inputs
74 * @a_srp_det: TRUE if the A-device detects SRP
75 * @a_vbus_vld: TRUE when VBUS voltage is in regulation
76 * @b_conn: TRUE if the A-device detects connection from the B-device
77 * @a_bus_resume: TRUE when the B-device detects that the A-device is signaling
78 * a resume (K state)
79 * B-Device state inputs
80 * @a_bus_suspend: TRUE when the B-device detects that the A-device has put the
81 * bus into suspend
82 * @a_conn: TRUE if the B-device detects a connection from the A-device
83 * @b_se0_srp: TRUE when the line has been at SE0 for more than the minimum
84 * time before generating SRP
85 * @b_ssend_srp: TRUE when the VBUS has been below VOTG_SESS_VLD for more than
86 * the minimum time before generating SRP
87 * @b_sess_vld: TRUE when the B-device detects that the voltage on VBUS is
88 * above VOTG_SESS_VLD
89 * @test_device: TRUE when the B-device switches to B-Host and detects an OTG
90 * test device. This must be set by host/hub driver
91 *
92 * Application inputs (A-Device)
93 * @a_bus_drop: TRUE when A-device application needs to power down the bus
94 * @a_bus_req: TRUE when A-device application wants to use the bus.
95 * FALSE to suspend the bus
96 *
97 * Application inputs (B-Device)
98 * @b_bus_req: TRUE during the time that the Application running on the
99 * B-device wants to use the bus
100 *
101 * Auxilary inputs (OTG v1.3 only. Obsolete now.)
102 * @a_sess_vld: TRUE if the A-device detects that VBUS is above VA_SESS_VLD
103 * @b_bus_suspend: TRUE when the A-device detects that the B-device has put
104 * the bus into suspend
105 * @b_bus_resume: TRUE when the A-device detects that the B-device is signaling
106 * resume on the bus
107 *
108 * OTG Output status. Read only for users. Updated by OTG FSM helpers defined
109 * in this file
110 *
111 * Outputs for Both A and B device
112 * @drv_vbus: TRUE when A-device is driving VBUS
113 * @loc_conn: TRUE when the local device has signaled that it is connected
114 * to the bus
115 * @loc_sof: TRUE when the local device is generating activity on the bus
116 * @adp_prb: TRUE when the local device is in the process of doing
117 * ADP probing
118 *
119 * Outputs for B-device state
120 * @adp_sns: TRUE when the B-device is in the process of carrying out
121 * ADP sensing
122 * @data_pulse: TRUE when the B-device is performing data line pulsing
123 *
124 * Internal Variables
125 *
126 * a_set_b_hnp_en: TRUE when the A-device has successfully set the
127 * b_hnp_enable bit in the B-device.
128 * Unused as OTG fsm uses otg->host->b_hnp_enable instead
129 * b_srp_done: TRUE when the B-device has completed initiating SRP
130 * b_hnp_enable: TRUE when the B-device has accepted the
131 * SetFeature(b_hnp_enable) B-device.
132 * Unused as OTG fsm uses otg->gadget->b_hnp_enable instead
133 * a_clr_err: Asserted (by application ?) to clear a_vbus_err due to an
134 * overcurrent condition and causes the A-device to transition
135 * to a_wait_vfall
136 */
137 struct otg_fsm {
138 /* Input */
139 int id;
140 int adp_change;
141 int power_up;
142 int a_srp_det;
143 int a_vbus_vld;
144 int b_conn;
145 int a_bus_resume;
146 int a_bus_suspend;
147 int a_conn;
148 int b_se0_srp;
149 int b_ssend_srp;
150 int b_sess_vld;
151 int test_device;
152 int a_bus_drop;
153 int a_bus_req;
154 int b_bus_req;
155
156 /* Auxilary inputs */
157 int a_sess_vld;
158 int b_bus_resume;
159 int b_bus_suspend;
160
161 /* Output */
162 int drv_vbus;
163 int loc_conn;
164 int loc_sof;
165 int adp_prb;
166 int adp_sns;
167 int data_pulse;
168
169 /* Internal variables */
170 int a_set_b_hnp_en;
171 int b_srp_done;
172 int b_hnp_enable;
173 int a_clr_err;
174
175 /* Informative variables. All unused as of now */
176 int a_bus_drop_inf;
177 int a_bus_req_inf;
178 int a_clr_err_inf;
179 int b_bus_req_inf;
180 /* Auxilary informative variables */
181 int a_suspend_req_inf;
182
183 /* Timeout indicator for timers */
184 int a_wait_vrise_tmout;
185 int a_wait_vfall_tmout;
186 int a_wait_bcon_tmout;
187 int a_aidl_bdis_tmout;
188 int b_ase0_brst_tmout;
189 int a_bidl_adis_tmout;
190
191 struct otg_fsm_ops *ops;
192 struct usb_otg *otg;
193
194 /* Current usb protocol used: 0:undefine; 1:host; 2:client */
195 int protocol;
196 struct mutex lock;
197 u8 *host_req_flag;
198 struct delayed_work hnp_polling_work;
199 bool state_changed;
200 };
201
202 struct otg_fsm_ops {
203 void (*chrg_vbus)(struct otg_fsm *fsm, int on);
204 void (*drv_vbus)(struct otg_fsm *fsm, int on);
205 void (*loc_conn)(struct otg_fsm *fsm, int on);
206 void (*loc_sof)(struct otg_fsm *fsm, int on);
207 void (*start_pulse)(struct otg_fsm *fsm);
208 void (*start_adp_prb)(struct otg_fsm *fsm);
209 void (*start_adp_sns)(struct otg_fsm *fsm);
210 void (*add_timer)(struct otg_fsm *fsm, enum otg_fsm_timer timer);
211 void (*del_timer)(struct otg_fsm *fsm, enum otg_fsm_timer timer);
212 int (*start_host)(struct otg_fsm *fsm, int on);
213 int (*start_gadget)(struct otg_fsm *fsm, int on);
214 };
215
216
217 static inline int otg_chrg_vbus(struct otg_fsm *fsm, int on)
218 {
219 if (!fsm->ops->chrg_vbus)
220 return -EOPNOTSUPP;
221 fsm->ops->chrg_vbus(fsm, on);
222 return 0;
223 }
224
225 static inline int otg_drv_vbus(struct otg_fsm *fsm, int on)
226 {
227 if (!fsm->ops->drv_vbus)
228 return -EOPNOTSUPP;
229 if (fsm->drv_vbus != on) {
230 fsm->drv_vbus = on;
231 fsm->ops->drv_vbus(fsm, on);
232 }
233 return 0;
234 }
235
236 static inline int otg_loc_conn(struct otg_fsm *fsm, int on)
237 {
238 if (!fsm->ops->loc_conn)
239 return -EOPNOTSUPP;
240 if (fsm->loc_conn != on) {
241 fsm->loc_conn = on;
242 fsm->ops->loc_conn(fsm, on);
243 }
244 return 0;
245 }
246
247 static inline int otg_loc_sof(struct otg_fsm *fsm, int on)
248 {
249 if (!fsm->ops->loc_sof)
250 return -EOPNOTSUPP;
251 if (fsm->loc_sof != on) {
252 fsm->loc_sof = on;
253 fsm->ops->loc_sof(fsm, on);
254 }
255 return 0;
256 }
257
258 static inline int otg_start_pulse(struct otg_fsm *fsm)
259 {
260 if (!fsm->ops->start_pulse)
261 return -EOPNOTSUPP;
262 if (!fsm->data_pulse) {
263 fsm->data_pulse = 1;
264 fsm->ops->start_pulse(fsm);
265 }
266 return 0;
267 }
268
269 static inline int otg_start_adp_prb(struct otg_fsm *fsm)
270 {
271 if (!fsm->ops->start_adp_prb)
272 return -EOPNOTSUPP;
273 if (!fsm->adp_prb) {
274 fsm->adp_sns = 0;
275 fsm->adp_prb = 1;
276 fsm->ops->start_adp_prb(fsm);
277 }
278 return 0;
279 }
280
281 static inline int otg_start_adp_sns(struct otg_fsm *fsm)
282 {
283 if (!fsm->ops->start_adp_sns)
284 return -EOPNOTSUPP;
285 if (!fsm->adp_sns) {
286 fsm->adp_sns = 1;
287 fsm->ops->start_adp_sns(fsm);
288 }
289 return 0;
290 }
291
292 static inline int otg_add_timer(struct otg_fsm *fsm, enum otg_fsm_timer timer)
293 {
294 if (!fsm->ops->add_timer)
295 return -EOPNOTSUPP;
296 fsm->ops->add_timer(fsm, timer);
297 return 0;
298 }
299
300 static inline int otg_del_timer(struct otg_fsm *fsm, enum otg_fsm_timer timer)
301 {
302 if (!fsm->ops->del_timer)
303 return -EOPNOTSUPP;
304 fsm->ops->del_timer(fsm, timer);
305 return 0;
306 }
307
308 static inline int otg_start_host(struct otg_fsm *fsm, int on)
309 {
310 if (!fsm->ops->start_host)
311 return -EOPNOTSUPP;
312 return fsm->ops->start_host(fsm, on);
313 }
314
315 static inline int otg_start_gadget(struct otg_fsm *fsm, int on)
316 {
317 if (!fsm->ops->start_gadget)
318 return -EOPNOTSUPP;
319 return fsm->ops->start_gadget(fsm, on);
320 }
321
322 int otg_statemachine(struct otg_fsm *fsm);
323
324 #endif /* __LINUX_USB_OTG_FSM_H */