1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2019-2020, The Linux Foundation. All rights reserved.
4  * Copyright (c) 2022, Linaro Ltd
5  */
6 #include <linux/auxiliary_bus.h>
7 #include <linux/bitfield.h>
8 #include <linux/cleanup.h>
9 #include <linux/module.h>
10 #include <linux/of.h>
11 #include <linux/of_device.h>
12 #include <linux/mutex.h>
13 #include <linux/property.h>
14 #include <linux/soc/qcom/pdr.h>
15 #include <drm/bridge/aux-bridge.h>
16 
17 #include <linux/usb/typec_altmode.h>
18 #include <linux/usb/typec_dp.h>
19 #include <linux/usb/typec_mux.h>
20 #include <linux/usb/typec_retimer.h>
21 
22 #include <linux/soc/qcom/pmic_glink.h>
23 
24 #define PMIC_GLINK_MAX_PORTS	3
25 
26 #define USBC_SC8180X_NOTIFY_IND	0x13
27 #define USBC_CMD_WRITE_REQ      0x15
28 #define USBC_NOTIFY_IND		0x16
29 
30 #define ALTMODE_PAN_EN		0x10
31 #define ALTMODE_PAN_ACK		0x11
32 
33 struct usbc_write_req {
34 	struct pmic_glink_hdr   hdr;
35 	__le32 cmd;
36 	__le32 arg;
37 	__le32 reserved;
38 };
39 
40 #define NOTIFY_PAYLOAD_SIZE 16
41 struct usbc_notify {
42 	struct pmic_glink_hdr hdr;
43 	char payload[NOTIFY_PAYLOAD_SIZE];
44 	u32 reserved;
45 };
46 
47 struct usbc_sc8180x_notify {
48 	struct pmic_glink_hdr hdr;
49 	__le32 notification;
50 	__le32 reserved[2];
51 };
52 
53 enum pmic_glink_altmode_pin_assignment {
54 	DPAM_HPD_OUT,
55 	DPAM_HPD_A,
56 	DPAM_HPD_B,
57 	DPAM_HPD_C,
58 	DPAM_HPD_D,
59 	DPAM_HPD_E,
60 	DPAM_HPD_F,
61 };
62 
63 struct pmic_glink_altmode;
64 
65 #define work_to_altmode_port(w) container_of((w), struct pmic_glink_altmode_port, work)
66 
67 struct pmic_glink_altmode_port {
68 	struct pmic_glink_altmode *altmode;
69 	unsigned int index;
70 
71 	struct typec_switch *typec_switch;
72 	struct typec_mux *typec_mux;
73 	struct typec_mux_state state;
74 	struct typec_retimer *typec_retimer;
75 	struct typec_retimer_state retimer_state;
76 	struct typec_altmode dp_alt;
77 
78 	struct work_struct work;
79 
80 	struct auxiliary_device *bridge;
81 
82 	enum typec_orientation orientation;
83 	u16 svid;
84 	u8 dp_data;
85 	u8 mode;
86 	u8 hpd_state;
87 	u8 hpd_irq;
88 };
89 
90 #define work_to_altmode(w) container_of((w), struct pmic_glink_altmode, enable_work)
91 
92 struct pmic_glink_altmode {
93 	struct device *dev;
94 
95 	unsigned int owner_id;
96 
97 	/* To synchronize WRITE_REQ acks */
98 	struct mutex lock;
99 
100 	struct completion pan_ack;
101 	struct pmic_glink_client *client;
102 
103 	struct work_struct enable_work;
104 
105 	struct pmic_glink_altmode_port ports[PMIC_GLINK_MAX_PORTS];
106 };
107 
pmic_glink_altmode_request(struct pmic_glink_altmode * altmode,u32 cmd,u32 arg)108 static int pmic_glink_altmode_request(struct pmic_glink_altmode *altmode, u32 cmd, u32 arg)
109 {
110 	struct usbc_write_req req = {};
111 	unsigned long left;
112 	int ret;
113 
114 	/*
115 	 * The USBC_CMD_WRITE_REQ ack doesn't identify the request, so wait for
116 	 * one ack at a time.
117 	 */
118 	guard(mutex)(&altmode->lock);
119 
120 	req.hdr.owner = cpu_to_le32(altmode->owner_id);
121 	req.hdr.type = cpu_to_le32(PMIC_GLINK_REQ_RESP);
122 	req.hdr.opcode = cpu_to_le32(USBC_CMD_WRITE_REQ);
123 	req.cmd = cpu_to_le32(cmd);
124 	req.arg = cpu_to_le32(arg);
125 
126 	ret = pmic_glink_send(altmode->client, &req, sizeof(req));
127 	if (ret) {
128 		dev_err(altmode->dev, "failed to send altmode request: %#x (%d)\n", cmd, ret);
129 		return ret;
130 	}
131 
132 	left = wait_for_completion_timeout(&altmode->pan_ack, 5 * HZ);
133 	if (!left) {
134 		dev_err(altmode->dev, "timeout waiting for altmode request ack for: %#x\n", cmd);
135 		return -ETIMEDOUT;
136 	}
137 
138 	return 0;
139 }
140 
pmic_glink_altmode_enable_dp(struct pmic_glink_altmode * altmode,struct pmic_glink_altmode_port * port,u8 mode,bool hpd_state,bool hpd_irq)141 static void pmic_glink_altmode_enable_dp(struct pmic_glink_altmode *altmode,
142 					 struct pmic_glink_altmode_port *port,
143 					 u8 mode, bool hpd_state,
144 					 bool hpd_irq)
145 {
146 	struct typec_displayport_data dp_data = {};
147 	int ret;
148 
149 	dp_data.status = DP_STATUS_ENABLED;
150 	if (hpd_state)
151 		dp_data.status |= DP_STATUS_HPD_STATE;
152 	if (hpd_irq)
153 		dp_data.status |= DP_STATUS_IRQ_HPD;
154 	dp_data.conf = DP_CONF_SET_PIN_ASSIGN(mode);
155 
156 	port->state.alt = &port->dp_alt;
157 	port->state.data = &dp_data;
158 	port->state.mode = TYPEC_MODAL_STATE(mode);
159 
160 	ret = typec_mux_set(port->typec_mux, &port->state);
161 	if (ret)
162 		dev_err(altmode->dev, "failed to switch mux to DP: %d\n", ret);
163 
164 	port->retimer_state.alt = &port->dp_alt;
165 	port->retimer_state.data = &dp_data;
166 	port->retimer_state.mode = TYPEC_MODAL_STATE(mode);
167 
168 	ret = typec_retimer_set(port->typec_retimer, &port->retimer_state);
169 	if (ret)
170 		dev_err(altmode->dev, "failed to setup retimer to DP: %d\n", ret);
171 }
172 
pmic_glink_altmode_enable_usb(struct pmic_glink_altmode * altmode,struct pmic_glink_altmode_port * port)173 static void pmic_glink_altmode_enable_usb(struct pmic_glink_altmode *altmode,
174 					  struct pmic_glink_altmode_port *port)
175 {
176 	int ret;
177 
178 	port->state.alt = NULL;
179 	port->state.data = NULL;
180 	port->state.mode = TYPEC_STATE_USB;
181 
182 	ret = typec_mux_set(port->typec_mux, &port->state);
183 	if (ret)
184 		dev_err(altmode->dev, "failed to switch mux to USB: %d\n", ret);
185 
186 	port->retimer_state.alt = NULL;
187 	port->retimer_state.data = NULL;
188 	port->retimer_state.mode = TYPEC_STATE_USB;
189 
190 	ret = typec_retimer_set(port->typec_retimer, &port->retimer_state);
191 	if (ret)
192 		dev_err(altmode->dev, "failed to setup retimer to USB: %d\n", ret);
193 }
194 
pmic_glink_altmode_safe(struct pmic_glink_altmode * altmode,struct pmic_glink_altmode_port * port)195 static void pmic_glink_altmode_safe(struct pmic_glink_altmode *altmode,
196 				    struct pmic_glink_altmode_port *port)
197 {
198 	int ret;
199 
200 	port->state.alt = NULL;
201 	port->state.data = NULL;
202 	port->state.mode = TYPEC_STATE_SAFE;
203 
204 	ret = typec_mux_set(port->typec_mux, &port->state);
205 	if (ret)
206 		dev_err(altmode->dev, "failed to switch mux to safe mode: %d\n", ret);
207 
208 	port->retimer_state.alt = NULL;
209 	port->retimer_state.data = NULL;
210 	port->retimer_state.mode = TYPEC_STATE_SAFE;
211 
212 	ret = typec_retimer_set(port->typec_retimer, &port->retimer_state);
213 	if (ret)
214 		dev_err(altmode->dev, "failed to setup retimer to USB: %d\n", ret);
215 }
216 
pmic_glink_altmode_worker(struct work_struct * work)217 static void pmic_glink_altmode_worker(struct work_struct *work)
218 {
219 	struct pmic_glink_altmode_port *alt_port = work_to_altmode_port(work);
220 	struct pmic_glink_altmode *altmode = alt_port->altmode;
221 
222 	typec_switch_set(alt_port->typec_switch, alt_port->orientation);
223 
224 	if (alt_port->svid == USB_TYPEC_DP_SID && alt_port->mode == 0xff)
225 		pmic_glink_altmode_safe(altmode, alt_port);
226 	else if (alt_port->svid == USB_TYPEC_DP_SID)
227 		pmic_glink_altmode_enable_dp(altmode, alt_port, alt_port->mode,
228 					     alt_port->hpd_state, alt_port->hpd_irq);
229 	else
230 		pmic_glink_altmode_enable_usb(altmode, alt_port);
231 
232 	drm_aux_hpd_bridge_notify(&alt_port->bridge->dev,
233 				  alt_port->hpd_state ?
234 				  connector_status_connected :
235 				  connector_status_disconnected);
236 
237 	pmic_glink_altmode_request(altmode, ALTMODE_PAN_ACK, alt_port->index);
238 }
239 
pmic_glink_altmode_orientation(unsigned int orientation)240 static enum typec_orientation pmic_glink_altmode_orientation(unsigned int orientation)
241 {
242 	if (orientation == 0)
243 		return TYPEC_ORIENTATION_NORMAL;
244 	else if (orientation == 1)
245 		return TYPEC_ORIENTATION_REVERSE;
246 	else
247 		return TYPEC_ORIENTATION_NONE;
248 }
249 
250 #define SC8180X_PORT_MASK		0x000000ff
251 #define SC8180X_ORIENTATION_MASK	0x0000ff00
252 #define SC8180X_MUX_MASK		0x00ff0000
253 #define SC8180X_MODE_MASK		0x3f000000
254 #define SC8180X_HPD_STATE_MASK		0x40000000
255 #define SC8180X_HPD_IRQ_MASK		0x80000000
256 
pmic_glink_altmode_sc8180xp_notify(struct pmic_glink_altmode * altmode,const void * data,size_t len)257 static void pmic_glink_altmode_sc8180xp_notify(struct pmic_glink_altmode *altmode,
258 					       const void *data, size_t len)
259 {
260 	struct pmic_glink_altmode_port *alt_port;
261 	const struct usbc_sc8180x_notify *msg;
262 	u32 notification;
263 	u8 orientation;
264 	u8 hpd_state;
265 	u8 hpd_irq;
266 	u16 svid;
267 	u8 port;
268 	u8 mode;
269 	u8 mux;
270 
271 	if (len != sizeof(*msg)) {
272 		dev_warn(altmode->dev, "invalid length of USBC_NOTIFY indication: %zd\n", len);
273 		return;
274 	}
275 
276 	msg = data;
277 	notification = le32_to_cpu(msg->notification);
278 	port = FIELD_GET(SC8180X_PORT_MASK, notification);
279 	orientation = FIELD_GET(SC8180X_ORIENTATION_MASK, notification);
280 	mux = FIELD_GET(SC8180X_MUX_MASK, notification);
281 	mode = FIELD_GET(SC8180X_MODE_MASK, notification);
282 	hpd_state = FIELD_GET(SC8180X_HPD_STATE_MASK, notification);
283 	hpd_irq = FIELD_GET(SC8180X_HPD_IRQ_MASK, notification);
284 
285 	svid = mux == 2 ? USB_TYPEC_DP_SID : 0;
286 
287 	if (port >= ARRAY_SIZE(altmode->ports) || !altmode->ports[port].altmode) {
288 		dev_dbg(altmode->dev, "notification on undefined port %d\n", port);
289 		return;
290 	}
291 
292 	alt_port = &altmode->ports[port];
293 	alt_port->orientation = pmic_glink_altmode_orientation(orientation);
294 	alt_port->svid = svid;
295 	alt_port->mode = mode;
296 	alt_port->hpd_state = hpd_state;
297 	alt_port->hpd_irq = hpd_irq;
298 	schedule_work(&alt_port->work);
299 }
300 
301 #define SC8280XP_DPAM_MASK	0x3f
302 #define SC8280XP_HPD_STATE_MASK BIT(6)
303 #define SC8280XP_HPD_IRQ_MASK	BIT(7)
304 
pmic_glink_altmode_sc8280xp_notify(struct pmic_glink_altmode * altmode,u16 svid,const void * data,size_t len)305 static void pmic_glink_altmode_sc8280xp_notify(struct pmic_glink_altmode *altmode,
306 					       u16 svid, const void *data, size_t len)
307 {
308 	struct pmic_glink_altmode_port *alt_port;
309 	const struct usbc_notify *notify;
310 	u8 orientation;
311 	u8 hpd_state;
312 	u8 hpd_irq;
313 	u8 mode;
314 	u8 port;
315 
316 	if (len != sizeof(*notify)) {
317 		dev_warn(altmode->dev, "invalid length USBC_NOTIFY_IND: %zd\n",
318 			 len);
319 		return;
320 	}
321 
322 	notify = data;
323 
324 	port = notify->payload[0];
325 	orientation = notify->payload[1];
326 	mode = FIELD_GET(SC8280XP_DPAM_MASK, notify->payload[8]) - DPAM_HPD_A;
327 	hpd_state = FIELD_GET(SC8280XP_HPD_STATE_MASK, notify->payload[8]);
328 	hpd_irq = FIELD_GET(SC8280XP_HPD_IRQ_MASK, notify->payload[8]);
329 
330 	if (port >= ARRAY_SIZE(altmode->ports) || !altmode->ports[port].altmode) {
331 		dev_dbg(altmode->dev, "notification on undefined port %d\n", port);
332 		return;
333 	}
334 
335 	alt_port = &altmode->ports[port];
336 	alt_port->orientation = pmic_glink_altmode_orientation(orientation);
337 	alt_port->svid = svid;
338 	alt_port->mode = mode;
339 	alt_port->hpd_state = hpd_state;
340 	alt_port->hpd_irq = hpd_irq;
341 	schedule_work(&alt_port->work);
342 }
343 
pmic_glink_altmode_callback(const void * data,size_t len,void * priv)344 static void pmic_glink_altmode_callback(const void *data, size_t len, void *priv)
345 {
346 	struct pmic_glink_altmode *altmode = priv;
347 	const struct pmic_glink_hdr *hdr = data;
348 	u16 opcode;
349 	u16 svid;
350 
351 	opcode = le32_to_cpu(hdr->opcode) & 0xff;
352 	svid = le32_to_cpu(hdr->opcode) >> 16;
353 
354 	switch (opcode) {
355 	case USBC_CMD_WRITE_REQ:
356 		complete(&altmode->pan_ack);
357 		break;
358 	case USBC_NOTIFY_IND:
359 		pmic_glink_altmode_sc8280xp_notify(altmode, svid, data, len);
360 		break;
361 	case USBC_SC8180X_NOTIFY_IND:
362 		pmic_glink_altmode_sc8180xp_notify(altmode, data, len);
363 		break;
364 	}
365 }
366 
pmic_glink_altmode_put_retimer(void * data)367 static void pmic_glink_altmode_put_retimer(void *data)
368 {
369 	typec_retimer_put(data);
370 }
371 
pmic_glink_altmode_put_mux(void * data)372 static void pmic_glink_altmode_put_mux(void *data)
373 {
374 	typec_mux_put(data);
375 }
376 
pmic_glink_altmode_put_switch(void * data)377 static void pmic_glink_altmode_put_switch(void *data)
378 {
379 	typec_switch_put(data);
380 }
381 
pmic_glink_altmode_enable_worker(struct work_struct * work)382 static void pmic_glink_altmode_enable_worker(struct work_struct *work)
383 {
384 	struct pmic_glink_altmode *altmode = work_to_altmode(work);
385 	int ret;
386 
387 	ret = pmic_glink_altmode_request(altmode, ALTMODE_PAN_EN, 0);
388 	if (ret)
389 		dev_err(altmode->dev, "failed to request altmode notifications: %d\n", ret);
390 }
391 
pmic_glink_altmode_pdr_notify(void * priv,int state)392 static void pmic_glink_altmode_pdr_notify(void *priv, int state)
393 {
394 	struct pmic_glink_altmode *altmode = priv;
395 
396 	if (state == SERVREG_SERVICE_STATE_UP)
397 		schedule_work(&altmode->enable_work);
398 }
399 
400 static const struct of_device_id pmic_glink_altmode_of_quirks[] = {
401 	{ .compatible = "qcom,sc8180x-pmic-glink", .data = (void *)PMIC_GLINK_OWNER_USBC },
402 	{}
403 };
404 
pmic_glink_altmode_probe(struct auxiliary_device * adev,const struct auxiliary_device_id * id)405 static int pmic_glink_altmode_probe(struct auxiliary_device *adev,
406 				    const struct auxiliary_device_id *id)
407 {
408 	struct pmic_glink_altmode_port *alt_port;
409 	struct pmic_glink_altmode *altmode;
410 	const struct of_device_id *match;
411 	struct fwnode_handle *fwnode;
412 	struct device *dev = &adev->dev;
413 	u32 port;
414 	int ret;
415 
416 	altmode = devm_kzalloc(dev, sizeof(*altmode), GFP_KERNEL);
417 	if (!altmode)
418 		return -ENOMEM;
419 
420 	altmode->dev = dev;
421 
422 	match = of_match_device(pmic_glink_altmode_of_quirks, dev->parent);
423 	if (match)
424 		altmode->owner_id = (unsigned long)match->data;
425 	else
426 		altmode->owner_id = PMIC_GLINK_OWNER_USBC_PAN;
427 
428 	INIT_WORK(&altmode->enable_work, pmic_glink_altmode_enable_worker);
429 	init_completion(&altmode->pan_ack);
430 	mutex_init(&altmode->lock);
431 
432 	device_for_each_child_node(dev, fwnode) {
433 		ret = fwnode_property_read_u32(fwnode, "reg", &port);
434 		if (ret < 0) {
435 			dev_err(dev, "missing reg property of %pOFn\n", fwnode);
436 			fwnode_handle_put(fwnode);
437 			return ret;
438 		}
439 
440 		if (port >= ARRAY_SIZE(altmode->ports)) {
441 			dev_warn(dev, "invalid connector number, ignoring\n");
442 			continue;
443 		}
444 
445 		if (altmode->ports[port].altmode) {
446 			dev_err(dev, "multiple connector definition for port %u\n", port);
447 			fwnode_handle_put(fwnode);
448 			return -EINVAL;
449 		}
450 
451 		alt_port = &altmode->ports[port];
452 		alt_port->altmode = altmode;
453 		alt_port->index = port;
454 		INIT_WORK(&alt_port->work, pmic_glink_altmode_worker);
455 
456 		alt_port->bridge = devm_drm_dp_hpd_bridge_alloc(dev, to_of_node(fwnode));
457 		if (IS_ERR(alt_port->bridge)) {
458 			fwnode_handle_put(fwnode);
459 			return PTR_ERR(alt_port->bridge);
460 		}
461 
462 		alt_port->dp_alt.svid = USB_TYPEC_DP_SID;
463 		alt_port->dp_alt.mode = USB_TYPEC_DP_MODE;
464 		alt_port->dp_alt.active = 1;
465 
466 		alt_port->typec_mux = fwnode_typec_mux_get(fwnode);
467 		if (IS_ERR(alt_port->typec_mux)) {
468 			fwnode_handle_put(fwnode);
469 			return dev_err_probe(dev, PTR_ERR(alt_port->typec_mux),
470 					     "failed to acquire mode-switch for port: %d\n",
471 					     port);
472 		}
473 
474 		ret = devm_add_action_or_reset(dev, pmic_glink_altmode_put_mux,
475 					       alt_port->typec_mux);
476 		if (ret) {
477 			fwnode_handle_put(fwnode);
478 			return ret;
479 		}
480 
481 		alt_port->typec_retimer = fwnode_typec_retimer_get(fwnode);
482 		if (IS_ERR(alt_port->typec_retimer)) {
483 			fwnode_handle_put(fwnode);
484 			return dev_err_probe(dev, PTR_ERR(alt_port->typec_retimer),
485 					     "failed to acquire retimer-switch for port: %d\n",
486 					     port);
487 		}
488 
489 		ret = devm_add_action_or_reset(dev, pmic_glink_altmode_put_retimer,
490 					       alt_port->typec_retimer);
491 		if (ret) {
492 			fwnode_handle_put(fwnode);
493 			return ret;
494 		}
495 
496 		alt_port->typec_switch = fwnode_typec_switch_get(fwnode);
497 		if (IS_ERR(alt_port->typec_switch)) {
498 			fwnode_handle_put(fwnode);
499 			return dev_err_probe(dev, PTR_ERR(alt_port->typec_switch),
500 					     "failed to acquire orientation-switch for port: %d\n",
501 					     port);
502 		}
503 
504 		ret = devm_add_action_or_reset(dev, pmic_glink_altmode_put_switch,
505 					       alt_port->typec_switch);
506 		if (ret) {
507 			fwnode_handle_put(fwnode);
508 			return ret;
509 		}
510 	}
511 
512 	for (port = 0; port < ARRAY_SIZE(altmode->ports); port++) {
513 		alt_port = &altmode->ports[port];
514 		if (!alt_port->bridge)
515 			continue;
516 
517 		ret = devm_drm_dp_hpd_bridge_add(dev, alt_port->bridge);
518 		if (ret)
519 			return ret;
520 	}
521 
522 	altmode->client = devm_pmic_glink_client_alloc(dev,
523 						       altmode->owner_id,
524 						       pmic_glink_altmode_callback,
525 						       pmic_glink_altmode_pdr_notify,
526 						       altmode);
527 	if (IS_ERR(altmode->client))
528 		return PTR_ERR(altmode->client);
529 
530 	pmic_glink_client_register(altmode->client);
531 
532 	return 0;
533 }
534 
535 static const struct auxiliary_device_id pmic_glink_altmode_id_table[] = {
536 	{ .name = "pmic_glink.altmode", },
537 	{},
538 };
539 MODULE_DEVICE_TABLE(auxiliary, pmic_glink_altmode_id_table);
540 
541 static struct auxiliary_driver pmic_glink_altmode_driver = {
542 	.name = "pmic_glink_altmode",
543 	.probe = pmic_glink_altmode_probe,
544 	.id_table = pmic_glink_altmode_id_table,
545 };
546 
547 module_auxiliary_driver(pmic_glink_altmode_driver);
548 
549 MODULE_DESCRIPTION("Qualcomm PMIC GLINK Altmode driver");
550 MODULE_LICENSE("GPL");
551