1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2022-2024, Linaro Ltd
4 * Authors:
5 * Bjorn Andersson
6 * Dmitry Baryshkov
7 */
8 #include <linux/auxiliary_bus.h>
9 #include <linux/bitops.h>
10 #include <linux/bitfield.h>
11 #include <linux/completion.h>
12 #include <linux/container_of.h>
13 #include <linux/module.h>
14 #include <linux/notifier.h>
15 #include <linux/of.h>
16 #include <linux/property.h>
17 #include <linux/string.h>
18 #include <linux/platform_data/lenovo-yoga-c630.h>
19 #include <linux/usb/typec_dp.h>
20
21 #include <drm/bridge/aux-bridge.h>
22
23 #include "ucsi.h"
24
25 #define LENOVO_EC_USB_MUX 0x08
26
27 #define USB_MUX_MUXC GENMASK(1, 0)
28 #define USB_MUX_CCST GENMASK(3, 2)
29 #define USB_MUX_DPPN GENMASK(7, 4)
30 #define USB_MUX_HPDS BIT(8)
31 #define USB_MUX_HSFL GENMASK(11, 9)
32
33 struct yoga_c630_ucsi {
34 struct yoga_c630_ec *ec;
35 struct ucsi *ucsi;
36 struct auxiliary_device *bridge;
37 struct notifier_block nb;
38 u16 version;
39 };
40
yoga_c630_ucsi_read_version(struct ucsi * ucsi,u16 * version)41 static int yoga_c630_ucsi_read_version(struct ucsi *ucsi, u16 *version)
42 {
43 struct yoga_c630_ucsi *uec = ucsi_get_drvdata(ucsi);
44
45 *version = uec->version;
46
47 return 0;
48 }
49
yoga_c630_ucsi_read_cci(struct ucsi * ucsi,u32 * cci)50 static int yoga_c630_ucsi_read_cci(struct ucsi *ucsi, u32 *cci)
51 {
52 struct yoga_c630_ucsi *uec = ucsi_get_drvdata(ucsi);
53 u8 buf[YOGA_C630_UCSI_READ_SIZE];
54 int ret;
55
56 ret = yoga_c630_ec_ucsi_read(uec->ec, buf);
57 if (ret)
58 return ret;
59
60 memcpy(cci, buf, sizeof(*cci));
61
62 return 0;
63 }
64
yoga_c630_ucsi_read_message_in(struct ucsi * ucsi,void * val,size_t val_len)65 static int yoga_c630_ucsi_read_message_in(struct ucsi *ucsi,
66 void *val, size_t val_len)
67 {
68 struct yoga_c630_ucsi *uec = ucsi_get_drvdata(ucsi);
69 u8 buf[YOGA_C630_UCSI_READ_SIZE];
70 int ret;
71
72 ret = yoga_c630_ec_ucsi_read(uec->ec, buf);
73 if (ret)
74 return ret;
75
76 memcpy(val, buf + YOGA_C630_UCSI_CCI_SIZE,
77 min(val_len, YOGA_C630_UCSI_DATA_SIZE));
78
79 return 0;
80 }
81
yoga_c630_ucsi_async_control(struct ucsi * ucsi,u64 command)82 static int yoga_c630_ucsi_async_control(struct ucsi *ucsi, u64 command)
83 {
84 struct yoga_c630_ucsi *uec = ucsi_get_drvdata(ucsi);
85
86 return yoga_c630_ec_ucsi_write(uec->ec, (u8*)&command);
87 }
88
yoga_c630_ucsi_sync_control(struct ucsi * ucsi,u64 command,u32 * cci,void * data,size_t size)89 static int yoga_c630_ucsi_sync_control(struct ucsi *ucsi,
90 u64 command,
91 u32 *cci,
92 void *data, size_t size)
93 {
94 int ret;
95
96 /*
97 * EC doesn't return connector's DP mode even though it is supported.
98 * Fake it.
99 */
100 if (UCSI_COMMAND(command) == UCSI_GET_ALTERNATE_MODES &&
101 UCSI_GET_ALTMODE_GET_CONNECTOR_NUMBER(command) == 1 &&
102 UCSI_ALTMODE_RECIPIENT(command) == UCSI_RECIPIENT_CON &&
103 UCSI_ALTMODE_OFFSET(command) == 0) {
104 static const struct ucsi_altmode alt = {
105 .svid = USB_TYPEC_DP_SID,
106 .mid = USB_TYPEC_DP_MODE,
107 };
108
109 dev_dbg(ucsi->dev, "faking DP altmode for con1\n");
110 memset(data, 0, size);
111 memcpy(data, &alt, min(sizeof(alt), size));
112 *cci = UCSI_CCI_COMMAND_COMPLETE | UCSI_SET_CCI_LENGTH(sizeof(alt));
113 return 0;
114 }
115
116 /*
117 * EC can return AltModes present on CON1 (port0, right) for CON2
118 * (port1, left) too. Ignore all requests going to CON2 (it doesn't
119 * support DP anyway).
120 */
121 if (UCSI_COMMAND(command) == UCSI_GET_ALTERNATE_MODES &&
122 UCSI_GET_ALTMODE_GET_CONNECTOR_NUMBER(command) == 2) {
123 dev_dbg(ucsi->dev, "ignoring altmodes for con2\n");
124 memset(data, 0, size);
125 *cci = UCSI_CCI_COMMAND_COMPLETE;
126 return 0;
127 }
128
129 ret = ucsi_sync_control_common(ucsi, command, cci, data, size);
130 if (ret < 0)
131 return ret;
132
133 /* UCSI_GET_CURRENT_CAM is off-by-one on all ports */
134 if (UCSI_COMMAND(command) == UCSI_GET_CURRENT_CAM && data)
135 ((u8 *)data)[0]--;
136
137 return ret;
138 }
139
yoga_c630_ucsi_update_altmodes(struct ucsi * ucsi,u8 recipient,struct ucsi_altmode * orig,struct ucsi_altmode * updated)140 static bool yoga_c630_ucsi_update_altmodes(struct ucsi *ucsi,
141 u8 recipient,
142 struct ucsi_altmode *orig,
143 struct ucsi_altmode *updated)
144 {
145 int i;
146
147 if (orig[0].svid == 0 || recipient != UCSI_RECIPIENT_SOP)
148 return false;
149
150 /* EC is nice and repeats altmodes again and again. Ignore copies. */
151 for (i = 1; i < UCSI_MAX_ALTMODES; i++) {
152 if (orig[i].svid == orig[0].svid) {
153 dev_dbg(ucsi->dev, "Found duplicate altmodes, starting from %d\n", i);
154 memset(&orig[i], 0, (UCSI_MAX_ALTMODES - i) * sizeof(*orig));
155 break;
156 }
157 }
158
159 return false;
160 }
161
yoga_c630_ucsi_update_connector(struct ucsi_connector * con)162 static void yoga_c630_ucsi_update_connector(struct ucsi_connector *con)
163 {
164 if (con->num == 1)
165 con->typec_cap.orientation_aware = true;
166 }
167
168 static const struct ucsi_operations yoga_c630_ucsi_ops = {
169 .read_version = yoga_c630_ucsi_read_version,
170 .read_cci = yoga_c630_ucsi_read_cci,
171 .poll_cci = yoga_c630_ucsi_read_cci,
172 .read_message_in = yoga_c630_ucsi_read_message_in,
173 .sync_control = yoga_c630_ucsi_sync_control,
174 .async_control = yoga_c630_ucsi_async_control,
175 .update_altmodes = yoga_c630_ucsi_update_altmodes,
176 .update_connector = yoga_c630_ucsi_update_connector,
177 };
178
yoga_c630_ucsi_read_port0_status(struct yoga_c630_ucsi * uec)179 static void yoga_c630_ucsi_read_port0_status(struct yoga_c630_ucsi *uec)
180 {
181 int val;
182 unsigned int muxc, ccst, dppn, hpds, hsfl;
183
184 val = yoga_c630_ec_read16(uec->ec, LENOVO_EC_USB_MUX);
185
186 muxc = FIELD_GET(USB_MUX_MUXC, val);
187 ccst = FIELD_GET(USB_MUX_CCST, val);
188 dppn = FIELD_GET(USB_MUX_DPPN, val);
189 hpds = FIELD_GET(USB_MUX_HPDS, val);
190 hsfl = FIELD_GET(USB_MUX_HSFL, val);
191
192 dev_dbg(uec->ucsi->dev, " mux %04x (muxc %d ccst %d dppn %d hpds %d hsfl %d)\n",
193 val,
194 muxc, ccst, dppn, hpds, hsfl);
195
196 if (uec->ucsi->connector && uec->ucsi->connector[0].port)
197 typec_set_orientation(uec->ucsi->connector[0].port,
198 ccst == 1 ?
199 TYPEC_ORIENTATION_REVERSE :
200 TYPEC_ORIENTATION_NORMAL);
201
202 if (uec->bridge)
203 drm_aux_hpd_bridge_notify(&uec->bridge->dev,
204 dppn != 0 ?
205 connector_status_connected :
206 connector_status_disconnected);
207
208 }
209
yoga_c630_ucsi_notify(struct notifier_block * nb,unsigned long action,void * data)210 static int yoga_c630_ucsi_notify(struct notifier_block *nb,
211 unsigned long action, void *data)
212 {
213 struct yoga_c630_ucsi *uec = container_of(nb, struct yoga_c630_ucsi, nb);
214 u32 cci;
215 int ret;
216
217 switch (action) {
218 case LENOVO_EC_EVENT_USB:
219 case LENOVO_EC_EVENT_HPD:
220 yoga_c630_ucsi_read_port0_status(uec);
221 ucsi_connector_change(uec->ucsi, 1);
222 return NOTIFY_OK;
223
224 case LENOVO_EC_EVENT_UCSI:
225 ret = uec->ucsi->ops->read_cci(uec->ucsi, &cci);
226 if (ret)
227 return NOTIFY_DONE;
228
229 ucsi_notify_common(uec->ucsi, cci);
230
231 return NOTIFY_OK;
232
233 default:
234 return NOTIFY_DONE;
235 }
236 }
237
yoga_c630_ucsi_probe(struct auxiliary_device * adev,const struct auxiliary_device_id * id)238 static int yoga_c630_ucsi_probe(struct auxiliary_device *adev,
239 const struct auxiliary_device_id *id)
240 {
241 struct yoga_c630_ec *ec = adev->dev.platform_data;
242 struct yoga_c630_ucsi *uec;
243 int ret;
244
245 uec = devm_kzalloc(&adev->dev, sizeof(*uec), GFP_KERNEL);
246 if (!uec)
247 return -ENOMEM;
248
249 uec->ec = ec;
250 uec->nb.notifier_call = yoga_c630_ucsi_notify;
251
252 device_for_each_child_node_scoped(&adev->dev, fwnode) {
253 u32 port;
254
255 ret = fwnode_property_read_u32(fwnode, "reg", &port);
256 if (ret < 0) {
257 dev_err(&adev->dev, "missing reg property of %pfwP\n", fwnode);
258 return ret;
259 }
260
261 /* DP is only on port0 */
262 if (port != 0)
263 continue;
264
265 uec->bridge = devm_drm_dp_hpd_bridge_alloc(&adev->dev, to_of_node(fwnode));
266 if (IS_ERR(uec->bridge))
267 return PTR_ERR(uec->bridge);
268 }
269
270 uec->ucsi = ucsi_create(&adev->dev, &yoga_c630_ucsi_ops);
271 if (IS_ERR(uec->ucsi))
272 return PTR_ERR(uec->ucsi);
273
274 ucsi_set_drvdata(uec->ucsi, uec);
275
276 uec->version = yoga_c630_ec_ucsi_get_version(uec->ec);
277
278 auxiliary_set_drvdata(adev, uec);
279
280 ret = yoga_c630_ec_register_notify(ec, &uec->nb);
281 if (ret)
282 goto err_destroy;
283
284 ret = ucsi_register(uec->ucsi);
285 if (ret)
286 goto err_unregister;
287
288 if (uec->bridge) {
289 ret = devm_drm_dp_hpd_bridge_add(&adev->dev, uec->bridge);
290 if (ret)
291 goto err_ucsi_unregister;
292 }
293
294 return 0;
295
296 err_ucsi_unregister:
297 ucsi_unregister(uec->ucsi);
298
299 err_unregister:
300 yoga_c630_ec_unregister_notify(uec->ec, &uec->nb);
301
302 err_destroy:
303 ucsi_destroy(uec->ucsi);
304
305 return ret;
306 }
307
yoga_c630_ucsi_remove(struct auxiliary_device * adev)308 static void yoga_c630_ucsi_remove(struct auxiliary_device *adev)
309 {
310 struct yoga_c630_ucsi *uec = auxiliary_get_drvdata(adev);
311
312 ucsi_unregister(uec->ucsi);
313 yoga_c630_ec_unregister_notify(uec->ec, &uec->nb);
314 ucsi_destroy(uec->ucsi);
315 }
316
317 static const struct auxiliary_device_id yoga_c630_ucsi_id_table[] = {
318 { .name = YOGA_C630_MOD_NAME "." YOGA_C630_DEV_UCSI, },
319 {}
320 };
321 MODULE_DEVICE_TABLE(auxiliary, yoga_c630_ucsi_id_table);
322
323 static struct auxiliary_driver yoga_c630_ucsi_driver = {
324 .name = YOGA_C630_DEV_UCSI,
325 .id_table = yoga_c630_ucsi_id_table,
326 .probe = yoga_c630_ucsi_probe,
327 .remove = yoga_c630_ucsi_remove,
328 };
329
330 module_auxiliary_driver(yoga_c630_ucsi_driver);
331
332 MODULE_DESCRIPTION("Lenovo Yoga C630 UCSI");
333 MODULE_LICENSE("GPL");
334