1 // SPDX-License-Identifier: GPL-2.0
2 // ChromeOS Embedded Controller extcon
3 //
4 // Copyright (C) 2017 Google, Inc.
5 // Author: Benson Leung <bleung@chromium.org>
6
7 #include <linux/extcon-provider.h>
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/notifier.h>
11 #include <linux/of.h>
12 #include <linux/platform_data/cros_ec_commands.h>
13 #include <linux/platform_data/cros_ec_proto.h>
14 #include <linux/platform_device.h>
15 #include <linux/slab.h>
16 #include <linux/sched.h>
17
18 struct cros_ec_extcon_info {
19 struct device *dev;
20 struct extcon_dev *edev;
21
22 int port_id;
23
24 struct cros_ec_device *ec;
25
26 struct notifier_block notifier;
27
28 unsigned int dr; /* data role */
29 bool pr; /* power role (true if VBUS enabled) */
30 bool dp; /* DisplayPort enabled */
31 bool mux; /* SuperSpeed (usb3) enabled */
32 unsigned int power_type;
33 };
34
35 static const unsigned int usb_type_c_cable[] = {
36 EXTCON_USB,
37 EXTCON_USB_HOST,
38 EXTCON_DISP_DP,
39 EXTCON_NONE,
40 };
41
42 enum usb_data_roles {
43 DR_NONE,
44 DR_HOST,
45 DR_DEVICE,
46 };
47
48 /**
49 * cros_ec_pd_command() - Send a command to the EC.
50 * @info: pointer to struct cros_ec_extcon_info
51 * @command: EC command
52 * @version: EC command version
53 * @outdata: EC command output data
54 * @outsize: Size of outdata
55 * @indata: EC command input data
56 * @insize: Size of indata
57 *
58 * Return: 0 on success, <0 on failure.
59 */
cros_ec_pd_command(struct cros_ec_extcon_info * info,unsigned int command,unsigned int version,void * outdata,unsigned int outsize,void * indata,unsigned int insize)60 static int cros_ec_pd_command(struct cros_ec_extcon_info *info,
61 unsigned int command,
62 unsigned int version,
63 void *outdata,
64 unsigned int outsize,
65 void *indata,
66 unsigned int insize)
67 {
68 struct cros_ec_command *msg;
69 int ret;
70
71 msg = kzalloc(struct_size(msg, data, max(outsize, insize)), GFP_KERNEL);
72 if (!msg)
73 return -ENOMEM;
74
75 msg->version = version;
76 msg->command = command;
77 msg->outsize = outsize;
78 msg->insize = insize;
79
80 if (outsize)
81 memcpy(msg->data, outdata, outsize);
82
83 ret = cros_ec_cmd_xfer_status(info->ec, msg);
84 if (ret >= 0 && insize)
85 memcpy(indata, msg->data, insize);
86
87 kfree(msg);
88 return ret;
89 }
90
91 /**
92 * cros_ec_usb_get_power_type() - Get power type info about PD device attached
93 * to given port.
94 * @info: pointer to struct cros_ec_extcon_info
95 *
96 * Return: power type on success, <0 on failure.
97 */
cros_ec_usb_get_power_type(struct cros_ec_extcon_info * info)98 static int cros_ec_usb_get_power_type(struct cros_ec_extcon_info *info)
99 {
100 struct ec_params_usb_pd_power_info req;
101 struct ec_response_usb_pd_power_info resp;
102 int ret;
103
104 req.port = info->port_id;
105 ret = cros_ec_pd_command(info, EC_CMD_USB_PD_POWER_INFO, 0,
106 &req, sizeof(req), &resp, sizeof(resp));
107 if (ret < 0)
108 return ret;
109
110 return resp.type;
111 }
112
113 /**
114 * cros_ec_usb_get_pd_mux_state() - Get PD mux state for given port.
115 * @info: pointer to struct cros_ec_extcon_info
116 *
117 * Return: PD mux state on success, <0 on failure.
118 */
cros_ec_usb_get_pd_mux_state(struct cros_ec_extcon_info * info)119 static int cros_ec_usb_get_pd_mux_state(struct cros_ec_extcon_info *info)
120 {
121 struct ec_params_usb_pd_mux_info req;
122 struct ec_response_usb_pd_mux_info resp;
123 int ret;
124
125 req.port = info->port_id;
126 ret = cros_ec_pd_command(info, EC_CMD_USB_PD_MUX_INFO, 0,
127 &req, sizeof(req),
128 &resp, sizeof(resp));
129 if (ret < 0)
130 return ret;
131
132 return resp.flags;
133 }
134
135 /**
136 * cros_ec_usb_get_role() - Get role info about possible PD device attached to a
137 * given port.
138 * @info: pointer to struct cros_ec_extcon_info
139 * @polarity: pointer to cable polarity (return value)
140 *
141 * Return: role info on success, -ENOTCONN if no cable is connected, <0 on
142 * failure.
143 */
cros_ec_usb_get_role(struct cros_ec_extcon_info * info,bool * polarity)144 static int cros_ec_usb_get_role(struct cros_ec_extcon_info *info,
145 bool *polarity)
146 {
147 struct ec_params_usb_pd_control pd_control;
148 struct ec_response_usb_pd_control_v1 resp;
149 int ret;
150
151 pd_control.port = info->port_id;
152 pd_control.role = USB_PD_CTRL_ROLE_NO_CHANGE;
153 pd_control.mux = USB_PD_CTRL_MUX_NO_CHANGE;
154 pd_control.swap = USB_PD_CTRL_SWAP_NONE;
155 ret = cros_ec_pd_command(info, EC_CMD_USB_PD_CONTROL, 1,
156 &pd_control, sizeof(pd_control),
157 &resp, sizeof(resp));
158 if (ret < 0)
159 return ret;
160
161 if (!(resp.enabled & PD_CTRL_RESP_ENABLED_CONNECTED))
162 return -ENOTCONN;
163
164 *polarity = resp.polarity;
165
166 return resp.role;
167 }
168
169 /**
170 * cros_ec_pd_get_num_ports() - Get number of EC charge ports.
171 * @info: pointer to struct cros_ec_extcon_info
172 *
173 * Return: number of ports on success, <0 on failure.
174 */
cros_ec_pd_get_num_ports(struct cros_ec_extcon_info * info)175 static int cros_ec_pd_get_num_ports(struct cros_ec_extcon_info *info)
176 {
177 struct ec_response_usb_pd_ports resp;
178 int ret;
179
180 ret = cros_ec_pd_command(info, EC_CMD_USB_PD_PORTS,
181 0, NULL, 0, &resp, sizeof(resp));
182 if (ret < 0)
183 return ret;
184
185 return resp.num_ports;
186 }
187
cros_ec_usb_role_string(unsigned int role)188 static const char *cros_ec_usb_role_string(unsigned int role)
189 {
190 return role == DR_NONE ? "DISCONNECTED" :
191 (role == DR_HOST ? "DFP" : "UFP");
192 }
193
cros_ec_usb_power_type_string(unsigned int type)194 static const char *cros_ec_usb_power_type_string(unsigned int type)
195 {
196 switch (type) {
197 case USB_CHG_TYPE_NONE:
198 return "USB_CHG_TYPE_NONE";
199 case USB_CHG_TYPE_PD:
200 return "USB_CHG_TYPE_PD";
201 case USB_CHG_TYPE_PROPRIETARY:
202 return "USB_CHG_TYPE_PROPRIETARY";
203 case USB_CHG_TYPE_C:
204 return "USB_CHG_TYPE_C";
205 case USB_CHG_TYPE_BC12_DCP:
206 return "USB_CHG_TYPE_BC12_DCP";
207 case USB_CHG_TYPE_BC12_CDP:
208 return "USB_CHG_TYPE_BC12_CDP";
209 case USB_CHG_TYPE_BC12_SDP:
210 return "USB_CHG_TYPE_BC12_SDP";
211 case USB_CHG_TYPE_OTHER:
212 return "USB_CHG_TYPE_OTHER";
213 case USB_CHG_TYPE_VBUS:
214 return "USB_CHG_TYPE_VBUS";
215 case USB_CHG_TYPE_UNKNOWN:
216 return "USB_CHG_TYPE_UNKNOWN";
217 default:
218 return "USB_CHG_TYPE_UNKNOWN";
219 }
220 }
221
cros_ec_usb_power_type_is_wall_wart(unsigned int type,unsigned int role)222 static bool cros_ec_usb_power_type_is_wall_wart(unsigned int type,
223 unsigned int role)
224 {
225 switch (type) {
226 /* FIXME : Guppy, Donnettes, and other chargers will be miscategorized
227 * because they identify with USB_CHG_TYPE_C, but we can't return true
228 * here from that code because that breaks Suzy-Q and other kinds of
229 * USB Type-C cables and peripherals.
230 */
231 case USB_CHG_TYPE_PROPRIETARY:
232 case USB_CHG_TYPE_BC12_DCP:
233 return true;
234 case USB_CHG_TYPE_PD:
235 case USB_CHG_TYPE_C:
236 case USB_CHG_TYPE_BC12_CDP:
237 case USB_CHG_TYPE_BC12_SDP:
238 case USB_CHG_TYPE_OTHER:
239 case USB_CHG_TYPE_VBUS:
240 case USB_CHG_TYPE_UNKNOWN:
241 case USB_CHG_TYPE_NONE:
242 default:
243 return false;
244 }
245 }
246
extcon_cros_ec_detect_cable(struct cros_ec_extcon_info * info,bool force)247 static int extcon_cros_ec_detect_cable(struct cros_ec_extcon_info *info,
248 bool force)
249 {
250 struct device *dev = info->dev;
251 int role, power_type;
252 unsigned int dr = DR_NONE;
253 bool pr = false;
254 bool polarity = false;
255 bool dp = false;
256 bool mux = false;
257 bool hpd = false;
258
259 power_type = cros_ec_usb_get_power_type(info);
260 if (power_type < 0) {
261 dev_err(dev, "failed getting power type err = %d\n",
262 power_type);
263 return power_type;
264 }
265
266 role = cros_ec_usb_get_role(info, &polarity);
267 if (role < 0) {
268 if (role != -ENOTCONN) {
269 dev_err(dev, "failed getting role err = %d\n", role);
270 return role;
271 }
272 dev_dbg(dev, "disconnected\n");
273 } else {
274 int pd_mux_state;
275
276 dr = (role & PD_CTRL_RESP_ROLE_DATA) ? DR_HOST : DR_DEVICE;
277 pr = (role & PD_CTRL_RESP_ROLE_POWER);
278 pd_mux_state = cros_ec_usb_get_pd_mux_state(info);
279 if (pd_mux_state < 0)
280 pd_mux_state = USB_PD_MUX_USB_ENABLED;
281
282 dp = pd_mux_state & USB_PD_MUX_DP_ENABLED;
283 mux = pd_mux_state & USB_PD_MUX_USB_ENABLED;
284 hpd = pd_mux_state & USB_PD_MUX_HPD_IRQ;
285
286 dev_dbg(dev,
287 "connected role 0x%x pwr type %d dr %d pr %d pol %d mux %d dp %d hpd %d\n",
288 role, power_type, dr, pr, polarity, mux, dp, hpd);
289 }
290
291 /*
292 * When there is no USB host (e.g. USB PD charger),
293 * we are not really a UFP for the AP.
294 */
295 if (dr == DR_DEVICE &&
296 cros_ec_usb_power_type_is_wall_wart(power_type, role))
297 dr = DR_NONE;
298
299 if (force || info->dr != dr || info->pr != pr || info->dp != dp ||
300 info->mux != mux || info->power_type != power_type) {
301 bool host_connected = false, device_connected = false;
302
303 dev_dbg(dev, "Type/Role switch! type = %s role = %s\n",
304 cros_ec_usb_power_type_string(power_type),
305 cros_ec_usb_role_string(dr));
306 info->dr = dr;
307 info->pr = pr;
308 info->dp = dp;
309 info->mux = mux;
310 info->power_type = power_type;
311
312 if (dr == DR_DEVICE)
313 device_connected = true;
314 else if (dr == DR_HOST)
315 host_connected = true;
316
317 extcon_set_state(info->edev, EXTCON_USB, device_connected);
318 extcon_set_state(info->edev, EXTCON_USB_HOST, host_connected);
319 extcon_set_state(info->edev, EXTCON_DISP_DP, dp);
320 extcon_set_property(info->edev, EXTCON_USB,
321 EXTCON_PROP_USB_VBUS,
322 (union extcon_property_value)(int)pr);
323 extcon_set_property(info->edev, EXTCON_USB_HOST,
324 EXTCON_PROP_USB_VBUS,
325 (union extcon_property_value)(int)pr);
326 extcon_set_property(info->edev, EXTCON_USB,
327 EXTCON_PROP_USB_TYPEC_POLARITY,
328 (union extcon_property_value)(int)polarity);
329 extcon_set_property(info->edev, EXTCON_USB_HOST,
330 EXTCON_PROP_USB_TYPEC_POLARITY,
331 (union extcon_property_value)(int)polarity);
332 extcon_set_property(info->edev, EXTCON_DISP_DP,
333 EXTCON_PROP_USB_TYPEC_POLARITY,
334 (union extcon_property_value)(int)polarity);
335 extcon_set_property(info->edev, EXTCON_USB,
336 EXTCON_PROP_USB_SS,
337 (union extcon_property_value)(int)mux);
338 extcon_set_property(info->edev, EXTCON_USB_HOST,
339 EXTCON_PROP_USB_SS,
340 (union extcon_property_value)(int)mux);
341 extcon_set_property(info->edev, EXTCON_DISP_DP,
342 EXTCON_PROP_USB_SS,
343 (union extcon_property_value)(int)mux);
344 extcon_set_property(info->edev, EXTCON_DISP_DP,
345 EXTCON_PROP_DISP_HPD,
346 (union extcon_property_value)(int)hpd);
347
348 extcon_sync(info->edev, EXTCON_USB);
349 extcon_sync(info->edev, EXTCON_USB_HOST);
350 extcon_sync(info->edev, EXTCON_DISP_DP);
351
352 } else if (hpd) {
353 extcon_set_property(info->edev, EXTCON_DISP_DP,
354 EXTCON_PROP_DISP_HPD,
355 (union extcon_property_value)(int)hpd);
356 extcon_sync(info->edev, EXTCON_DISP_DP);
357 }
358
359 return 0;
360 }
361
extcon_cros_ec_event(struct notifier_block * nb,unsigned long queued_during_suspend,void * _notify)362 static int extcon_cros_ec_event(struct notifier_block *nb,
363 unsigned long queued_during_suspend,
364 void *_notify)
365 {
366 struct cros_ec_extcon_info *info;
367 struct cros_ec_device *ec;
368 u32 host_event;
369
370 info = container_of(nb, struct cros_ec_extcon_info, notifier);
371 ec = info->ec;
372
373 host_event = cros_ec_get_host_event(ec);
374 if (host_event & (EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU) |
375 EC_HOST_EVENT_MASK(EC_HOST_EVENT_USB_MUX))) {
376 extcon_cros_ec_detect_cable(info, false);
377 return NOTIFY_OK;
378 }
379
380 return NOTIFY_DONE;
381 }
382
extcon_cros_ec_probe(struct platform_device * pdev)383 static int extcon_cros_ec_probe(struct platform_device *pdev)
384 {
385 struct cros_ec_extcon_info *info;
386 struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent);
387 struct device *dev = &pdev->dev;
388 struct device_node *np = dev->of_node;
389 int numports, ret;
390
391 info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
392 if (!info)
393 return -ENOMEM;
394
395 info->dev = dev;
396 info->ec = ec;
397
398 if (np) {
399 u32 port;
400
401 ret = of_property_read_u32(np, "google,usb-port-id", &port);
402 if (ret < 0) {
403 dev_err(dev, "Missing google,usb-port-id property\n");
404 return ret;
405 }
406 info->port_id = port;
407 } else {
408 info->port_id = pdev->id;
409 }
410
411 numports = cros_ec_pd_get_num_ports(info);
412 if (numports < 0) {
413 dev_err(dev, "failed getting number of ports! ret = %d\n",
414 numports);
415 return numports;
416 }
417
418 if (info->port_id >= numports) {
419 dev_err(dev, "This system only supports %d ports\n", numports);
420 return -ENODEV;
421 }
422
423 info->edev = devm_extcon_dev_allocate(dev, usb_type_c_cable);
424 if (IS_ERR(info->edev)) {
425 dev_err(dev, "failed to allocate extcon device\n");
426 return -ENOMEM;
427 }
428
429 ret = devm_extcon_dev_register(dev, info->edev);
430 if (ret < 0) {
431 dev_err(dev, "failed to register extcon device\n");
432 return ret;
433 }
434
435 extcon_set_property_capability(info->edev, EXTCON_USB,
436 EXTCON_PROP_USB_VBUS);
437 extcon_set_property_capability(info->edev, EXTCON_USB_HOST,
438 EXTCON_PROP_USB_VBUS);
439 extcon_set_property_capability(info->edev, EXTCON_USB,
440 EXTCON_PROP_USB_TYPEC_POLARITY);
441 extcon_set_property_capability(info->edev, EXTCON_USB_HOST,
442 EXTCON_PROP_USB_TYPEC_POLARITY);
443 extcon_set_property_capability(info->edev, EXTCON_DISP_DP,
444 EXTCON_PROP_USB_TYPEC_POLARITY);
445 extcon_set_property_capability(info->edev, EXTCON_USB,
446 EXTCON_PROP_USB_SS);
447 extcon_set_property_capability(info->edev, EXTCON_USB_HOST,
448 EXTCON_PROP_USB_SS);
449 extcon_set_property_capability(info->edev, EXTCON_DISP_DP,
450 EXTCON_PROP_USB_SS);
451 extcon_set_property_capability(info->edev, EXTCON_DISP_DP,
452 EXTCON_PROP_DISP_HPD);
453
454 info->dr = DR_NONE;
455 info->pr = false;
456
457 platform_set_drvdata(pdev, info);
458
459 /* Get PD events from the EC */
460 info->notifier.notifier_call = extcon_cros_ec_event;
461 ret = blocking_notifier_chain_register(&info->ec->event_notifier,
462 &info->notifier);
463 if (ret < 0) {
464 dev_err(dev, "failed to register notifier\n");
465 return ret;
466 }
467
468 /* Perform initial detection */
469 ret = extcon_cros_ec_detect_cable(info, true);
470 if (ret < 0) {
471 dev_err(dev, "failed to detect initial cable state\n");
472 goto unregister_notifier;
473 }
474
475 return 0;
476
477 unregister_notifier:
478 blocking_notifier_chain_unregister(&info->ec->event_notifier,
479 &info->notifier);
480 return ret;
481 }
482
extcon_cros_ec_remove(struct platform_device * pdev)483 static void extcon_cros_ec_remove(struct platform_device *pdev)
484 {
485 struct cros_ec_extcon_info *info = platform_get_drvdata(pdev);
486
487 blocking_notifier_chain_unregister(&info->ec->event_notifier,
488 &info->notifier);
489 }
490
491 #ifdef CONFIG_PM_SLEEP
extcon_cros_ec_suspend(struct device * dev)492 static int extcon_cros_ec_suspend(struct device *dev)
493 {
494 return 0;
495 }
496
extcon_cros_ec_resume(struct device * dev)497 static int extcon_cros_ec_resume(struct device *dev)
498 {
499 int ret;
500 struct cros_ec_extcon_info *info = dev_get_drvdata(dev);
501
502 ret = extcon_cros_ec_detect_cable(info, true);
503 if (ret < 0)
504 dev_err(dev, "failed to detect cable state on resume\n");
505
506 return 0;
507 }
508
509 static const struct dev_pm_ops extcon_cros_ec_dev_pm_ops = {
510 SET_SYSTEM_SLEEP_PM_OPS(extcon_cros_ec_suspend, extcon_cros_ec_resume)
511 };
512
513 #define DEV_PM_OPS (&extcon_cros_ec_dev_pm_ops)
514 #else
515 #define DEV_PM_OPS NULL
516 #endif /* CONFIG_PM_SLEEP */
517
518 #ifdef CONFIG_OF
519 static const struct of_device_id extcon_cros_ec_of_match[] = {
520 { .compatible = "google,extcon-usbc-cros-ec" },
521 { /* sentinel */ }
522 };
523 MODULE_DEVICE_TABLE(of, extcon_cros_ec_of_match);
524 #endif /* CONFIG_OF */
525
526 static struct platform_driver extcon_cros_ec_driver = {
527 .driver = {
528 .name = "extcon-usbc-cros-ec",
529 .of_match_table = of_match_ptr(extcon_cros_ec_of_match),
530 .pm = DEV_PM_OPS,
531 },
532 .remove_new = extcon_cros_ec_remove,
533 .probe = extcon_cros_ec_probe,
534 };
535
536 module_platform_driver(extcon_cros_ec_driver);
537
538 MODULE_DESCRIPTION("ChromeOS Embedded Controller extcon driver");
539 MODULE_AUTHOR("Benson Leung <bleung@chromium.org>");
540 MODULE_LICENSE("GPL v2");
541