1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Greybus interface code
4  *
5  * Copyright 2014 Google Inc.
6  * Copyright 2014 Linaro Ltd.
7  */
8 
9 #include <linux/delay.h>
10 #include <linux/greybus.h>
11 
12 #include "greybus_trace.h"
13 
14 #define GB_INTERFACE_MODE_SWITCH_TIMEOUT	2000
15 
16 #define GB_INTERFACE_DEVICE_ID_BAD	0xff
17 
18 #define GB_INTERFACE_AUTOSUSPEND_MS			3000
19 
20 /* Time required for interface to enter standby before disabling REFCLK */
21 #define GB_INTERFACE_SUSPEND_HIBERNATE_DELAY_MS			20
22 
23 /* Don't-care selector index */
24 #define DME_SELECTOR_INDEX_NULL		0
25 
26 /* DME attributes */
27 /* FIXME: remove ES2 support and DME_T_TST_SRC_INCREMENT */
28 #define DME_T_TST_SRC_INCREMENT		0x4083
29 
30 #define DME_DDBL1_MANUFACTURERID	0x5003
31 #define DME_DDBL1_PRODUCTID		0x5004
32 
33 #define DME_TOSHIBA_GMP_VID		0x6000
34 #define DME_TOSHIBA_GMP_PID		0x6001
35 #define DME_TOSHIBA_GMP_SN0		0x6002
36 #define DME_TOSHIBA_GMP_SN1		0x6003
37 #define DME_TOSHIBA_GMP_INIT_STATUS	0x6101
38 
39 /* DDBL1 Manufacturer and Product ids */
40 #define TOSHIBA_DMID			0x0126
41 #define TOSHIBA_ES2_BRIDGE_DPID		0x1000
42 #define TOSHIBA_ES3_APBRIDGE_DPID	0x1001
43 #define TOSHIBA_ES3_GBPHY_DPID	0x1002
44 
45 static int gb_interface_hibernate_link(struct gb_interface *intf);
46 static int gb_interface_refclk_set(struct gb_interface *intf, bool enable);
47 
gb_interface_dme_attr_get(struct gb_interface * intf,u16 attr,u32 * val)48 static int gb_interface_dme_attr_get(struct gb_interface *intf,
49 				     u16 attr, u32 *val)
50 {
51 	return gb_svc_dme_peer_get(intf->hd->svc, intf->interface_id,
52 					attr, DME_SELECTOR_INDEX_NULL, val);
53 }
54 
gb_interface_read_ara_dme(struct gb_interface * intf)55 static int gb_interface_read_ara_dme(struct gb_interface *intf)
56 {
57 	u32 sn0, sn1;
58 	int ret;
59 
60 	/*
61 	 * Unless this is a Toshiba bridge, bail out until we have defined
62 	 * standard GMP attributes.
63 	 */
64 	if (intf->ddbl1_manufacturer_id != TOSHIBA_DMID) {
65 		dev_err(&intf->dev, "unknown manufacturer %08x\n",
66 			intf->ddbl1_manufacturer_id);
67 		return -ENODEV;
68 	}
69 
70 	ret = gb_interface_dme_attr_get(intf, DME_TOSHIBA_GMP_VID,
71 					&intf->vendor_id);
72 	if (ret)
73 		return ret;
74 
75 	ret = gb_interface_dme_attr_get(intf, DME_TOSHIBA_GMP_PID,
76 					&intf->product_id);
77 	if (ret)
78 		return ret;
79 
80 	ret = gb_interface_dme_attr_get(intf, DME_TOSHIBA_GMP_SN0, &sn0);
81 	if (ret)
82 		return ret;
83 
84 	ret = gb_interface_dme_attr_get(intf, DME_TOSHIBA_GMP_SN1, &sn1);
85 	if (ret)
86 		return ret;
87 
88 	intf->serial_number = (u64)sn1 << 32 | sn0;
89 
90 	return 0;
91 }
92 
gb_interface_read_dme(struct gb_interface * intf)93 static int gb_interface_read_dme(struct gb_interface *intf)
94 {
95 	int ret;
96 
97 	/* DME attributes have already been read */
98 	if (intf->dme_read)
99 		return 0;
100 
101 	ret = gb_interface_dme_attr_get(intf, DME_DDBL1_MANUFACTURERID,
102 					&intf->ddbl1_manufacturer_id);
103 	if (ret)
104 		return ret;
105 
106 	ret = gb_interface_dme_attr_get(intf, DME_DDBL1_PRODUCTID,
107 					&intf->ddbl1_product_id);
108 	if (ret)
109 		return ret;
110 
111 	if (intf->ddbl1_manufacturer_id == TOSHIBA_DMID &&
112 	    intf->ddbl1_product_id == TOSHIBA_ES2_BRIDGE_DPID) {
113 		intf->quirks |= GB_INTERFACE_QUIRK_NO_GMP_IDS;
114 		intf->quirks |= GB_INTERFACE_QUIRK_NO_INIT_STATUS;
115 	}
116 
117 	ret = gb_interface_read_ara_dme(intf);
118 	if (ret)
119 		return ret;
120 
121 	intf->dme_read = true;
122 
123 	return 0;
124 }
125 
gb_interface_route_create(struct gb_interface * intf)126 static int gb_interface_route_create(struct gb_interface *intf)
127 {
128 	struct gb_svc *svc = intf->hd->svc;
129 	u8 intf_id = intf->interface_id;
130 	u8 device_id;
131 	int ret;
132 
133 	/* Allocate an interface device id. */
134 	ret = ida_alloc_range(&svc->device_id_map, GB_SVC_DEVICE_ID_MIN,
135 			      GB_SVC_DEVICE_ID_MAX, GFP_KERNEL);
136 	if (ret < 0) {
137 		dev_err(&intf->dev, "failed to allocate device id: %d\n", ret);
138 		return ret;
139 	}
140 	device_id = ret;
141 
142 	ret = gb_svc_intf_device_id(svc, intf_id, device_id);
143 	if (ret) {
144 		dev_err(&intf->dev, "failed to set device id %u: %d\n",
145 			device_id, ret);
146 		goto err_ida_remove;
147 	}
148 
149 	/* FIXME: Hard-coded AP device id. */
150 	ret = gb_svc_route_create(svc, svc->ap_intf_id, GB_SVC_DEVICE_ID_AP,
151 				  intf_id, device_id);
152 	if (ret) {
153 		dev_err(&intf->dev, "failed to create route: %d\n", ret);
154 		goto err_svc_id_free;
155 	}
156 
157 	intf->device_id = device_id;
158 
159 	return 0;
160 
161 err_svc_id_free:
162 	/*
163 	 * XXX Should we tell SVC that this id doesn't belong to interface
164 	 * XXX anymore.
165 	 */
166 err_ida_remove:
167 	ida_free(&svc->device_id_map, device_id);
168 
169 	return ret;
170 }
171 
gb_interface_route_destroy(struct gb_interface * intf)172 static void gb_interface_route_destroy(struct gb_interface *intf)
173 {
174 	struct gb_svc *svc = intf->hd->svc;
175 
176 	if (intf->device_id == GB_INTERFACE_DEVICE_ID_BAD)
177 		return;
178 
179 	gb_svc_route_destroy(svc, svc->ap_intf_id, intf->interface_id);
180 	ida_free(&svc->device_id_map, intf->device_id);
181 	intf->device_id = GB_INTERFACE_DEVICE_ID_BAD;
182 }
183 
184 /* Locking: Caller holds the interface mutex. */
gb_interface_legacy_mode_switch(struct gb_interface * intf)185 static int gb_interface_legacy_mode_switch(struct gb_interface *intf)
186 {
187 	int ret;
188 
189 	dev_info(&intf->dev, "legacy mode switch detected\n");
190 
191 	/* Mark as disconnected to prevent I/O during disable. */
192 	intf->disconnected = true;
193 	gb_interface_disable(intf);
194 	intf->disconnected = false;
195 
196 	ret = gb_interface_enable(intf);
197 	if (ret) {
198 		dev_err(&intf->dev, "failed to re-enable interface: %d\n", ret);
199 		gb_interface_deactivate(intf);
200 	}
201 
202 	return ret;
203 }
204 
gb_interface_mailbox_event(struct gb_interface * intf,u16 result,u32 mailbox)205 void gb_interface_mailbox_event(struct gb_interface *intf, u16 result,
206 				u32 mailbox)
207 {
208 	mutex_lock(&intf->mutex);
209 
210 	if (result) {
211 		dev_warn(&intf->dev,
212 			 "mailbox event with UniPro error: 0x%04x\n",
213 			 result);
214 		goto err_disable;
215 	}
216 
217 	if (mailbox != GB_SVC_INTF_MAILBOX_GREYBUS) {
218 		dev_warn(&intf->dev,
219 			 "mailbox event with unexpected value: 0x%08x\n",
220 			 mailbox);
221 		goto err_disable;
222 	}
223 
224 	if (intf->quirks & GB_INTERFACE_QUIRK_LEGACY_MODE_SWITCH) {
225 		gb_interface_legacy_mode_switch(intf);
226 		goto out_unlock;
227 	}
228 
229 	if (!intf->mode_switch) {
230 		dev_warn(&intf->dev, "unexpected mailbox event: 0x%08x\n",
231 			 mailbox);
232 		goto err_disable;
233 	}
234 
235 	dev_info(&intf->dev, "mode switch detected\n");
236 
237 	complete(&intf->mode_switch_completion);
238 
239 out_unlock:
240 	mutex_unlock(&intf->mutex);
241 
242 	return;
243 
244 err_disable:
245 	gb_interface_disable(intf);
246 	gb_interface_deactivate(intf);
247 	mutex_unlock(&intf->mutex);
248 }
249 
gb_interface_mode_switch_work(struct work_struct * work)250 static void gb_interface_mode_switch_work(struct work_struct *work)
251 {
252 	struct gb_interface *intf;
253 	struct gb_control *control;
254 	unsigned long timeout;
255 	int ret;
256 
257 	intf = container_of(work, struct gb_interface, mode_switch_work);
258 
259 	mutex_lock(&intf->mutex);
260 	/* Make sure interface is still enabled. */
261 	if (!intf->enabled) {
262 		dev_dbg(&intf->dev, "mode switch aborted\n");
263 		intf->mode_switch = false;
264 		mutex_unlock(&intf->mutex);
265 		goto out_interface_put;
266 	}
267 
268 	/*
269 	 * Prepare the control device for mode switch and make sure to get an
270 	 * extra reference before it goes away during interface disable.
271 	 */
272 	control = gb_control_get(intf->control);
273 	gb_control_mode_switch_prepare(control);
274 	gb_interface_disable(intf);
275 	mutex_unlock(&intf->mutex);
276 
277 	timeout = msecs_to_jiffies(GB_INTERFACE_MODE_SWITCH_TIMEOUT);
278 	ret = wait_for_completion_interruptible_timeout(
279 			&intf->mode_switch_completion, timeout);
280 
281 	/* Finalise control-connection mode switch. */
282 	gb_control_mode_switch_complete(control);
283 	gb_control_put(control);
284 
285 	if (ret < 0) {
286 		dev_err(&intf->dev, "mode switch interrupted\n");
287 		goto err_deactivate;
288 	} else if (ret == 0) {
289 		dev_err(&intf->dev, "mode switch timed out\n");
290 		goto err_deactivate;
291 	}
292 
293 	/* Re-enable (re-enumerate) interface if still active. */
294 	mutex_lock(&intf->mutex);
295 	intf->mode_switch = false;
296 	if (intf->active) {
297 		ret = gb_interface_enable(intf);
298 		if (ret) {
299 			dev_err(&intf->dev, "failed to re-enable interface: %d\n",
300 				ret);
301 			gb_interface_deactivate(intf);
302 		}
303 	}
304 	mutex_unlock(&intf->mutex);
305 
306 out_interface_put:
307 	gb_interface_put(intf);
308 
309 	return;
310 
311 err_deactivate:
312 	mutex_lock(&intf->mutex);
313 	intf->mode_switch = false;
314 	gb_interface_deactivate(intf);
315 	mutex_unlock(&intf->mutex);
316 
317 	gb_interface_put(intf);
318 }
319 
gb_interface_request_mode_switch(struct gb_interface * intf)320 int gb_interface_request_mode_switch(struct gb_interface *intf)
321 {
322 	int ret = 0;
323 
324 	mutex_lock(&intf->mutex);
325 	if (intf->mode_switch) {
326 		ret = -EBUSY;
327 		goto out_unlock;
328 	}
329 
330 	intf->mode_switch = true;
331 	reinit_completion(&intf->mode_switch_completion);
332 
333 	/*
334 	 * Get a reference to the interface device, which will be put once the
335 	 * mode switch is complete.
336 	 */
337 	get_device(&intf->dev);
338 
339 	if (!queue_work(system_long_wq, &intf->mode_switch_work)) {
340 		put_device(&intf->dev);
341 		ret = -EBUSY;
342 		goto out_unlock;
343 	}
344 
345 out_unlock:
346 	mutex_unlock(&intf->mutex);
347 
348 	return ret;
349 }
350 EXPORT_SYMBOL_GPL(gb_interface_request_mode_switch);
351 
352 /*
353  * T_TstSrcIncrement is written by the module on ES2 as a stand-in for the
354  * init-status attribute DME_TOSHIBA_INIT_STATUS. The AP needs to read and
355  * clear it after reading a non-zero value from it.
356  *
357  * FIXME: This is module-hardware dependent and needs to be extended for every
358  * type of module we want to support.
359  */
gb_interface_read_and_clear_init_status(struct gb_interface * intf)360 static int gb_interface_read_and_clear_init_status(struct gb_interface *intf)
361 {
362 	struct gb_host_device *hd = intf->hd;
363 	unsigned long bootrom_quirks;
364 	unsigned long s2l_quirks;
365 	int ret;
366 	u32 value;
367 	u16 attr;
368 	u8 init_status;
369 
370 	/*
371 	 * ES2 bridges use T_TstSrcIncrement for the init status.
372 	 *
373 	 * FIXME: Remove ES2 support
374 	 */
375 	if (intf->quirks & GB_INTERFACE_QUIRK_NO_INIT_STATUS)
376 		attr = DME_T_TST_SRC_INCREMENT;
377 	else
378 		attr = DME_TOSHIBA_GMP_INIT_STATUS;
379 
380 	ret = gb_svc_dme_peer_get(hd->svc, intf->interface_id, attr,
381 				  DME_SELECTOR_INDEX_NULL, &value);
382 	if (ret)
383 		return ret;
384 
385 	/*
386 	 * A nonzero init status indicates the module has finished
387 	 * initializing.
388 	 */
389 	if (!value) {
390 		dev_err(&intf->dev, "invalid init status\n");
391 		return -ENODEV;
392 	}
393 
394 	/*
395 	 * Extract the init status.
396 	 *
397 	 * For ES2: We need to check lowest 8 bits of 'value'.
398 	 * For ES3: We need to check highest 8 bits out of 32 of 'value'.
399 	 *
400 	 * FIXME: Remove ES2 support
401 	 */
402 	if (intf->quirks & GB_INTERFACE_QUIRK_NO_INIT_STATUS)
403 		init_status = value & 0xff;
404 	else
405 		init_status = value >> 24;
406 
407 	/*
408 	 * Check if the interface is executing the quirky ES3 bootrom that,
409 	 * for example, requires E2EFC, CSD and CSV to be disabled.
410 	 */
411 	bootrom_quirks = GB_INTERFACE_QUIRK_NO_CPORT_FEATURES |
412 				GB_INTERFACE_QUIRK_FORCED_DISABLE |
413 				GB_INTERFACE_QUIRK_LEGACY_MODE_SWITCH |
414 				GB_INTERFACE_QUIRK_NO_BUNDLE_ACTIVATE;
415 
416 	s2l_quirks = GB_INTERFACE_QUIRK_NO_PM;
417 
418 	switch (init_status) {
419 	case GB_INIT_BOOTROM_UNIPRO_BOOT_STARTED:
420 	case GB_INIT_BOOTROM_FALLBACK_UNIPRO_BOOT_STARTED:
421 		intf->quirks |= bootrom_quirks;
422 		break;
423 	case GB_INIT_S2_LOADER_BOOT_STARTED:
424 		/* S2 Loader doesn't support runtime PM */
425 		intf->quirks &= ~bootrom_quirks;
426 		intf->quirks |= s2l_quirks;
427 		break;
428 	default:
429 		intf->quirks &= ~bootrom_quirks;
430 		intf->quirks &= ~s2l_quirks;
431 	}
432 
433 	/* Clear the init status. */
434 	return gb_svc_dme_peer_set(hd->svc, intf->interface_id, attr,
435 				   DME_SELECTOR_INDEX_NULL, 0);
436 }
437 
438 /* interface sysfs attributes */
439 #define gb_interface_attr(field, type)					\
440 static ssize_t field##_show(struct device *dev,				\
441 			    struct device_attribute *attr,		\
442 			    char *buf)					\
443 {									\
444 	struct gb_interface *intf = to_gb_interface(dev);		\
445 	return scnprintf(buf, PAGE_SIZE, type"\n", intf->field);	\
446 }									\
447 static DEVICE_ATTR_RO(field)
448 
449 gb_interface_attr(ddbl1_manufacturer_id, "0x%08x");
450 gb_interface_attr(ddbl1_product_id, "0x%08x");
451 gb_interface_attr(interface_id, "%u");
452 gb_interface_attr(vendor_id, "0x%08x");
453 gb_interface_attr(product_id, "0x%08x");
454 gb_interface_attr(serial_number, "0x%016llx");
455 
voltage_now_show(struct device * dev,struct device_attribute * attr,char * buf)456 static ssize_t voltage_now_show(struct device *dev,
457 				struct device_attribute *attr, char *buf)
458 {
459 	struct gb_interface *intf = to_gb_interface(dev);
460 	int ret;
461 	u32 measurement;
462 
463 	ret = gb_svc_pwrmon_intf_sample_get(intf->hd->svc, intf->interface_id,
464 					    GB_SVC_PWRMON_TYPE_VOL,
465 					    &measurement);
466 	if (ret) {
467 		dev_err(&intf->dev, "failed to get voltage sample (%d)\n", ret);
468 		return ret;
469 	}
470 
471 	return sprintf(buf, "%u\n", measurement);
472 }
473 static DEVICE_ATTR_RO(voltage_now);
474 
current_now_show(struct device * dev,struct device_attribute * attr,char * buf)475 static ssize_t current_now_show(struct device *dev,
476 				struct device_attribute *attr, char *buf)
477 {
478 	struct gb_interface *intf = to_gb_interface(dev);
479 	int ret;
480 	u32 measurement;
481 
482 	ret = gb_svc_pwrmon_intf_sample_get(intf->hd->svc, intf->interface_id,
483 					    GB_SVC_PWRMON_TYPE_CURR,
484 					    &measurement);
485 	if (ret) {
486 		dev_err(&intf->dev, "failed to get current sample (%d)\n", ret);
487 		return ret;
488 	}
489 
490 	return sprintf(buf, "%u\n", measurement);
491 }
492 static DEVICE_ATTR_RO(current_now);
493 
power_now_show(struct device * dev,struct device_attribute * attr,char * buf)494 static ssize_t power_now_show(struct device *dev,
495 			      struct device_attribute *attr, char *buf)
496 {
497 	struct gb_interface *intf = to_gb_interface(dev);
498 	int ret;
499 	u32 measurement;
500 
501 	ret = gb_svc_pwrmon_intf_sample_get(intf->hd->svc, intf->interface_id,
502 					    GB_SVC_PWRMON_TYPE_PWR,
503 					    &measurement);
504 	if (ret) {
505 		dev_err(&intf->dev, "failed to get power sample (%d)\n", ret);
506 		return ret;
507 	}
508 
509 	return sprintf(buf, "%u\n", measurement);
510 }
511 static DEVICE_ATTR_RO(power_now);
512 
power_state_show(struct device * dev,struct device_attribute * attr,char * buf)513 static ssize_t power_state_show(struct device *dev,
514 				struct device_attribute *attr, char *buf)
515 {
516 	struct gb_interface *intf = to_gb_interface(dev);
517 
518 	if (intf->active)
519 		return scnprintf(buf, PAGE_SIZE, "on\n");
520 	else
521 		return scnprintf(buf, PAGE_SIZE, "off\n");
522 }
523 
power_state_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)524 static ssize_t power_state_store(struct device *dev,
525 				 struct device_attribute *attr, const char *buf,
526 				 size_t len)
527 {
528 	struct gb_interface *intf = to_gb_interface(dev);
529 	bool activate;
530 	int ret = 0;
531 
532 	if (kstrtobool(buf, &activate))
533 		return -EINVAL;
534 
535 	mutex_lock(&intf->mutex);
536 
537 	if (activate == intf->active)
538 		goto unlock;
539 
540 	if (activate) {
541 		ret = gb_interface_activate(intf);
542 		if (ret) {
543 			dev_err(&intf->dev,
544 				"failed to activate interface: %d\n", ret);
545 			goto unlock;
546 		}
547 
548 		ret = gb_interface_enable(intf);
549 		if (ret) {
550 			dev_err(&intf->dev,
551 				"failed to enable interface: %d\n", ret);
552 			gb_interface_deactivate(intf);
553 			goto unlock;
554 		}
555 	} else {
556 		gb_interface_disable(intf);
557 		gb_interface_deactivate(intf);
558 	}
559 
560 unlock:
561 	mutex_unlock(&intf->mutex);
562 
563 	if (ret)
564 		return ret;
565 
566 	return len;
567 }
568 static DEVICE_ATTR_RW(power_state);
569 
gb_interface_type_string(struct gb_interface * intf)570 static const char *gb_interface_type_string(struct gb_interface *intf)
571 {
572 	static const char * const types[] = {
573 		[GB_INTERFACE_TYPE_INVALID] = "invalid",
574 		[GB_INTERFACE_TYPE_UNKNOWN] = "unknown",
575 		[GB_INTERFACE_TYPE_DUMMY] = "dummy",
576 		[GB_INTERFACE_TYPE_UNIPRO] = "unipro",
577 		[GB_INTERFACE_TYPE_GREYBUS] = "greybus",
578 	};
579 
580 	return types[intf->type];
581 }
582 
interface_type_show(struct device * dev,struct device_attribute * attr,char * buf)583 static ssize_t interface_type_show(struct device *dev,
584 				   struct device_attribute *attr, char *buf)
585 {
586 	struct gb_interface *intf = to_gb_interface(dev);
587 
588 	return sprintf(buf, "%s\n", gb_interface_type_string(intf));
589 }
590 static DEVICE_ATTR_RO(interface_type);
591 
592 static struct attribute *interface_unipro_attrs[] = {
593 	&dev_attr_ddbl1_manufacturer_id.attr,
594 	&dev_attr_ddbl1_product_id.attr,
595 	NULL
596 };
597 
598 static struct attribute *interface_greybus_attrs[] = {
599 	&dev_attr_vendor_id.attr,
600 	&dev_attr_product_id.attr,
601 	&dev_attr_serial_number.attr,
602 	NULL
603 };
604 
605 static struct attribute *interface_power_attrs[] = {
606 	&dev_attr_voltage_now.attr,
607 	&dev_attr_current_now.attr,
608 	&dev_attr_power_now.attr,
609 	&dev_attr_power_state.attr,
610 	NULL
611 };
612 
613 static struct attribute *interface_common_attrs[] = {
614 	&dev_attr_interface_id.attr,
615 	&dev_attr_interface_type.attr,
616 	NULL
617 };
618 
interface_unipro_is_visible(struct kobject * kobj,struct attribute * attr,int n)619 static umode_t interface_unipro_is_visible(struct kobject *kobj,
620 					   struct attribute *attr, int n)
621 {
622 	struct device *dev = kobj_to_dev(kobj);
623 	struct gb_interface *intf = to_gb_interface(dev);
624 
625 	switch (intf->type) {
626 	case GB_INTERFACE_TYPE_UNIPRO:
627 	case GB_INTERFACE_TYPE_GREYBUS:
628 		return attr->mode;
629 	default:
630 		return 0;
631 	}
632 }
633 
interface_greybus_is_visible(struct kobject * kobj,struct attribute * attr,int n)634 static umode_t interface_greybus_is_visible(struct kobject *kobj,
635 					    struct attribute *attr, int n)
636 {
637 	struct device *dev = kobj_to_dev(kobj);
638 	struct gb_interface *intf = to_gb_interface(dev);
639 
640 	switch (intf->type) {
641 	case GB_INTERFACE_TYPE_GREYBUS:
642 		return attr->mode;
643 	default:
644 		return 0;
645 	}
646 }
647 
interface_power_is_visible(struct kobject * kobj,struct attribute * attr,int n)648 static umode_t interface_power_is_visible(struct kobject *kobj,
649 					  struct attribute *attr, int n)
650 {
651 	struct device *dev = kobj_to_dev(kobj);
652 	struct gb_interface *intf = to_gb_interface(dev);
653 
654 	switch (intf->type) {
655 	case GB_INTERFACE_TYPE_UNIPRO:
656 	case GB_INTERFACE_TYPE_GREYBUS:
657 		return attr->mode;
658 	default:
659 		return 0;
660 	}
661 }
662 
663 static const struct attribute_group interface_unipro_group = {
664 	.is_visible	= interface_unipro_is_visible,
665 	.attrs		= interface_unipro_attrs,
666 };
667 
668 static const struct attribute_group interface_greybus_group = {
669 	.is_visible	= interface_greybus_is_visible,
670 	.attrs		= interface_greybus_attrs,
671 };
672 
673 static const struct attribute_group interface_power_group = {
674 	.is_visible	= interface_power_is_visible,
675 	.attrs		= interface_power_attrs,
676 };
677 
678 static const struct attribute_group interface_common_group = {
679 	.attrs		= interface_common_attrs,
680 };
681 
682 static const struct attribute_group *interface_groups[] = {
683 	&interface_unipro_group,
684 	&interface_greybus_group,
685 	&interface_power_group,
686 	&interface_common_group,
687 	NULL
688 };
689 
gb_interface_release(struct device * dev)690 static void gb_interface_release(struct device *dev)
691 {
692 	struct gb_interface *intf = to_gb_interface(dev);
693 
694 	trace_gb_interface_release(intf);
695 
696 	cancel_work_sync(&intf->mode_switch_work);
697 	kfree(intf);
698 }
699 
700 #ifdef CONFIG_PM
gb_interface_suspend(struct device * dev)701 static int gb_interface_suspend(struct device *dev)
702 {
703 	struct gb_interface *intf = to_gb_interface(dev);
704 	int ret;
705 
706 	ret = gb_control_interface_suspend_prepare(intf->control);
707 	if (ret)
708 		return ret;
709 
710 	ret = gb_control_suspend(intf->control);
711 	if (ret)
712 		goto err_hibernate_abort;
713 
714 	ret = gb_interface_hibernate_link(intf);
715 	if (ret)
716 		return ret;
717 
718 	/* Delay to allow interface to enter standby before disabling refclk */
719 	msleep(GB_INTERFACE_SUSPEND_HIBERNATE_DELAY_MS);
720 
721 	ret = gb_interface_refclk_set(intf, false);
722 	if (ret)
723 		return ret;
724 
725 	return 0;
726 
727 err_hibernate_abort:
728 	gb_control_interface_hibernate_abort(intf->control);
729 
730 	return ret;
731 }
732 
gb_interface_resume(struct device * dev)733 static int gb_interface_resume(struct device *dev)
734 {
735 	struct gb_interface *intf = to_gb_interface(dev);
736 	struct gb_svc *svc = intf->hd->svc;
737 	int ret;
738 
739 	ret = gb_interface_refclk_set(intf, true);
740 	if (ret)
741 		return ret;
742 
743 	ret = gb_svc_intf_resume(svc, intf->interface_id);
744 	if (ret)
745 		return ret;
746 
747 	ret = gb_control_resume(intf->control);
748 	if (ret)
749 		return ret;
750 
751 	return 0;
752 }
753 
gb_interface_runtime_idle(struct device * dev)754 static int gb_interface_runtime_idle(struct device *dev)
755 {
756 	pm_runtime_mark_last_busy(dev);
757 	pm_request_autosuspend(dev);
758 
759 	return 0;
760 }
761 #endif
762 
763 static const struct dev_pm_ops gb_interface_pm_ops = {
764 	SET_RUNTIME_PM_OPS(gb_interface_suspend, gb_interface_resume,
765 			   gb_interface_runtime_idle)
766 };
767 
768 const struct device_type greybus_interface_type = {
769 	.name =		"greybus_interface",
770 	.release =	gb_interface_release,
771 	.pm =		&gb_interface_pm_ops,
772 };
773 
774 /*
775  * A Greybus module represents a user-replaceable component on a GMP
776  * phone.  An interface is the physical connection on that module.  A
777  * module may have more than one interface.
778  *
779  * Create a gb_interface structure to represent a discovered interface.
780  * The position of interface within the Endo is encoded in "interface_id"
781  * argument.
782  *
783  * Returns a pointer to the new interfce or a null pointer if a
784  * failure occurs due to memory exhaustion.
785  */
gb_interface_create(struct gb_module * module,u8 interface_id)786 struct gb_interface *gb_interface_create(struct gb_module *module,
787 					 u8 interface_id)
788 {
789 	struct gb_host_device *hd = module->hd;
790 	struct gb_interface *intf;
791 
792 	intf = kzalloc(sizeof(*intf), GFP_KERNEL);
793 	if (!intf)
794 		return NULL;
795 
796 	intf->hd = hd;		/* XXX refcount? */
797 	intf->module = module;
798 	intf->interface_id = interface_id;
799 	INIT_LIST_HEAD(&intf->bundles);
800 	INIT_LIST_HEAD(&intf->manifest_descs);
801 	mutex_init(&intf->mutex);
802 	INIT_WORK(&intf->mode_switch_work, gb_interface_mode_switch_work);
803 	init_completion(&intf->mode_switch_completion);
804 
805 	/* Invalid device id to start with */
806 	intf->device_id = GB_INTERFACE_DEVICE_ID_BAD;
807 
808 	intf->dev.parent = &module->dev;
809 	intf->dev.bus = &greybus_bus_type;
810 	intf->dev.type = &greybus_interface_type;
811 	intf->dev.groups = interface_groups;
812 	intf->dev.dma_mask = module->dev.dma_mask;
813 	device_initialize(&intf->dev);
814 	dev_set_name(&intf->dev, "%s.%u", dev_name(&module->dev),
815 		     interface_id);
816 
817 	pm_runtime_set_autosuspend_delay(&intf->dev,
818 					 GB_INTERFACE_AUTOSUSPEND_MS);
819 
820 	trace_gb_interface_create(intf);
821 
822 	return intf;
823 }
824 
gb_interface_vsys_set(struct gb_interface * intf,bool enable)825 static int gb_interface_vsys_set(struct gb_interface *intf, bool enable)
826 {
827 	struct gb_svc *svc = intf->hd->svc;
828 	int ret;
829 
830 	dev_dbg(&intf->dev, "%s - %d\n", __func__, enable);
831 
832 	ret = gb_svc_intf_vsys_set(svc, intf->interface_id, enable);
833 	if (ret) {
834 		dev_err(&intf->dev, "failed to set v_sys: %d\n", ret);
835 		return ret;
836 	}
837 
838 	return 0;
839 }
840 
gb_interface_refclk_set(struct gb_interface * intf,bool enable)841 static int gb_interface_refclk_set(struct gb_interface *intf, bool enable)
842 {
843 	struct gb_svc *svc = intf->hd->svc;
844 	int ret;
845 
846 	dev_dbg(&intf->dev, "%s - %d\n", __func__, enable);
847 
848 	ret = gb_svc_intf_refclk_set(svc, intf->interface_id, enable);
849 	if (ret) {
850 		dev_err(&intf->dev, "failed to set refclk: %d\n", ret);
851 		return ret;
852 	}
853 
854 	return 0;
855 }
856 
gb_interface_unipro_set(struct gb_interface * intf,bool enable)857 static int gb_interface_unipro_set(struct gb_interface *intf, bool enable)
858 {
859 	struct gb_svc *svc = intf->hd->svc;
860 	int ret;
861 
862 	dev_dbg(&intf->dev, "%s - %d\n", __func__, enable);
863 
864 	ret = gb_svc_intf_unipro_set(svc, intf->interface_id, enable);
865 	if (ret) {
866 		dev_err(&intf->dev, "failed to set UniPro: %d\n", ret);
867 		return ret;
868 	}
869 
870 	return 0;
871 }
872 
gb_interface_activate_operation(struct gb_interface * intf,enum gb_interface_type * intf_type)873 static int gb_interface_activate_operation(struct gb_interface *intf,
874 					   enum gb_interface_type *intf_type)
875 {
876 	struct gb_svc *svc = intf->hd->svc;
877 	u8 type;
878 	int ret;
879 
880 	dev_dbg(&intf->dev, "%s\n", __func__);
881 
882 	ret = gb_svc_intf_activate(svc, intf->interface_id, &type);
883 	if (ret) {
884 		dev_err(&intf->dev, "failed to activate: %d\n", ret);
885 		return ret;
886 	}
887 
888 	switch (type) {
889 	case GB_SVC_INTF_TYPE_DUMMY:
890 		*intf_type = GB_INTERFACE_TYPE_DUMMY;
891 		/* FIXME: handle as an error for now */
892 		return -ENODEV;
893 	case GB_SVC_INTF_TYPE_UNIPRO:
894 		*intf_type = GB_INTERFACE_TYPE_UNIPRO;
895 		dev_err(&intf->dev, "interface type UniPro not supported\n");
896 		/* FIXME: handle as an error for now */
897 		return -ENODEV;
898 	case GB_SVC_INTF_TYPE_GREYBUS:
899 		*intf_type = GB_INTERFACE_TYPE_GREYBUS;
900 		break;
901 	default:
902 		dev_err(&intf->dev, "unknown interface type: %u\n", type);
903 		*intf_type = GB_INTERFACE_TYPE_UNKNOWN;
904 		return -ENODEV;
905 	}
906 
907 	return 0;
908 }
909 
gb_interface_hibernate_link(struct gb_interface * intf)910 static int gb_interface_hibernate_link(struct gb_interface *intf)
911 {
912 	struct gb_svc *svc = intf->hd->svc;
913 
914 	return gb_svc_intf_set_power_mode_hibernate(svc, intf->interface_id);
915 }
916 
_gb_interface_activate(struct gb_interface * intf,enum gb_interface_type * type)917 static int _gb_interface_activate(struct gb_interface *intf,
918 				  enum gb_interface_type *type)
919 {
920 	int ret;
921 
922 	*type = GB_INTERFACE_TYPE_UNKNOWN;
923 
924 	if (intf->ejected || intf->removed)
925 		return -ENODEV;
926 
927 	ret = gb_interface_vsys_set(intf, true);
928 	if (ret)
929 		return ret;
930 
931 	ret = gb_interface_refclk_set(intf, true);
932 	if (ret)
933 		goto err_vsys_disable;
934 
935 	ret = gb_interface_unipro_set(intf, true);
936 	if (ret)
937 		goto err_refclk_disable;
938 
939 	ret = gb_interface_activate_operation(intf, type);
940 	if (ret) {
941 		switch (*type) {
942 		case GB_INTERFACE_TYPE_UNIPRO:
943 		case GB_INTERFACE_TYPE_GREYBUS:
944 			goto err_hibernate_link;
945 		default:
946 			goto err_unipro_disable;
947 		}
948 	}
949 
950 	ret = gb_interface_read_dme(intf);
951 	if (ret)
952 		goto err_hibernate_link;
953 
954 	ret = gb_interface_route_create(intf);
955 	if (ret)
956 		goto err_hibernate_link;
957 
958 	intf->active = true;
959 
960 	trace_gb_interface_activate(intf);
961 
962 	return 0;
963 
964 err_hibernate_link:
965 	gb_interface_hibernate_link(intf);
966 err_unipro_disable:
967 	gb_interface_unipro_set(intf, false);
968 err_refclk_disable:
969 	gb_interface_refclk_set(intf, false);
970 err_vsys_disable:
971 	gb_interface_vsys_set(intf, false);
972 
973 	return ret;
974 }
975 
976 /*
977  * At present, we assume a UniPro-only module to be a Greybus module that
978  * failed to send its mailbox poke. There is some reason to believe that this
979  * is because of a bug in the ES3 bootrom.
980  *
981  * FIXME: Check if this is a Toshiba bridge before retrying?
982  */
_gb_interface_activate_es3_hack(struct gb_interface * intf,enum gb_interface_type * type)983 static int _gb_interface_activate_es3_hack(struct gb_interface *intf,
984 					   enum gb_interface_type *type)
985 {
986 	int retries = 3;
987 	int ret;
988 
989 	while (retries--) {
990 		ret = _gb_interface_activate(intf, type);
991 		if (ret == -ENODEV && *type == GB_INTERFACE_TYPE_UNIPRO)
992 			continue;
993 
994 		break;
995 	}
996 
997 	return ret;
998 }
999 
1000 /*
1001  * Activate an interface.
1002  *
1003  * Locking: Caller holds the interface mutex.
1004  */
gb_interface_activate(struct gb_interface * intf)1005 int gb_interface_activate(struct gb_interface *intf)
1006 {
1007 	enum gb_interface_type type;
1008 	int ret;
1009 
1010 	switch (intf->type) {
1011 	case GB_INTERFACE_TYPE_INVALID:
1012 	case GB_INTERFACE_TYPE_GREYBUS:
1013 		ret = _gb_interface_activate_es3_hack(intf, &type);
1014 		break;
1015 	default:
1016 		ret = _gb_interface_activate(intf, &type);
1017 	}
1018 
1019 	/* Make sure type is detected correctly during reactivation. */
1020 	if (intf->type != GB_INTERFACE_TYPE_INVALID) {
1021 		if (type != intf->type) {
1022 			dev_err(&intf->dev, "failed to detect interface type\n");
1023 
1024 			if (!ret)
1025 				gb_interface_deactivate(intf);
1026 
1027 			return -EIO;
1028 		}
1029 	} else {
1030 		intf->type = type;
1031 	}
1032 
1033 	return ret;
1034 }
1035 
1036 /*
1037  * Deactivate an interface.
1038  *
1039  * Locking: Caller holds the interface mutex.
1040  */
gb_interface_deactivate(struct gb_interface * intf)1041 void gb_interface_deactivate(struct gb_interface *intf)
1042 {
1043 	if (!intf->active)
1044 		return;
1045 
1046 	trace_gb_interface_deactivate(intf);
1047 
1048 	/* Abort any ongoing mode switch. */
1049 	if (intf->mode_switch)
1050 		complete(&intf->mode_switch_completion);
1051 
1052 	gb_interface_route_destroy(intf);
1053 	gb_interface_hibernate_link(intf);
1054 	gb_interface_unipro_set(intf, false);
1055 	gb_interface_refclk_set(intf, false);
1056 	gb_interface_vsys_set(intf, false);
1057 
1058 	intf->active = false;
1059 }
1060 
1061 /*
1062  * Enable an interface by enabling its control connection, fetching the
1063  * manifest and other information over it, and finally registering its child
1064  * devices.
1065  *
1066  * Locking: Caller holds the interface mutex.
1067  */
gb_interface_enable(struct gb_interface * intf)1068 int gb_interface_enable(struct gb_interface *intf)
1069 {
1070 	struct gb_control *control;
1071 	struct gb_bundle *bundle, *tmp;
1072 	int ret, size;
1073 	void *manifest;
1074 
1075 	ret = gb_interface_read_and_clear_init_status(intf);
1076 	if (ret) {
1077 		dev_err(&intf->dev, "failed to clear init status: %d\n", ret);
1078 		return ret;
1079 	}
1080 
1081 	/* Establish control connection */
1082 	control = gb_control_create(intf);
1083 	if (IS_ERR(control)) {
1084 		dev_err(&intf->dev, "failed to create control device: %ld\n",
1085 			PTR_ERR(control));
1086 		return PTR_ERR(control);
1087 	}
1088 	intf->control = control;
1089 
1090 	ret = gb_control_enable(intf->control);
1091 	if (ret)
1092 		goto err_put_control;
1093 
1094 	/* Get manifest size using control protocol on CPort */
1095 	size = gb_control_get_manifest_size_operation(intf);
1096 	if (size <= 0) {
1097 		dev_err(&intf->dev, "failed to get manifest size: %d\n", size);
1098 
1099 		if (size)
1100 			ret = size;
1101 		else
1102 			ret =  -EINVAL;
1103 
1104 		goto err_disable_control;
1105 	}
1106 
1107 	manifest = kmalloc(size, GFP_KERNEL);
1108 	if (!manifest) {
1109 		ret = -ENOMEM;
1110 		goto err_disable_control;
1111 	}
1112 
1113 	/* Get manifest using control protocol on CPort */
1114 	ret = gb_control_get_manifest_operation(intf, manifest, size);
1115 	if (ret) {
1116 		dev_err(&intf->dev, "failed to get manifest: %d\n", ret);
1117 		goto err_free_manifest;
1118 	}
1119 
1120 	/*
1121 	 * Parse the manifest and build up our data structures representing
1122 	 * what's in it.
1123 	 */
1124 	if (!gb_manifest_parse(intf, manifest, size)) {
1125 		dev_err(&intf->dev, "failed to parse manifest\n");
1126 		ret = -EINVAL;
1127 		goto err_destroy_bundles;
1128 	}
1129 
1130 	ret = gb_control_get_bundle_versions(intf->control);
1131 	if (ret)
1132 		goto err_destroy_bundles;
1133 
1134 	/* Register the control device and any bundles */
1135 	ret = gb_control_add(intf->control);
1136 	if (ret)
1137 		goto err_destroy_bundles;
1138 
1139 	pm_runtime_use_autosuspend(&intf->dev);
1140 	pm_runtime_get_noresume(&intf->dev);
1141 	pm_runtime_set_active(&intf->dev);
1142 	pm_runtime_enable(&intf->dev);
1143 
1144 	list_for_each_entry_safe_reverse(bundle, tmp, &intf->bundles, links) {
1145 		ret = gb_bundle_add(bundle);
1146 		if (ret) {
1147 			gb_bundle_destroy(bundle);
1148 			continue;
1149 		}
1150 	}
1151 
1152 	kfree(manifest);
1153 
1154 	intf->enabled = true;
1155 
1156 	pm_runtime_put(&intf->dev);
1157 
1158 	trace_gb_interface_enable(intf);
1159 
1160 	return 0;
1161 
1162 err_destroy_bundles:
1163 	list_for_each_entry_safe(bundle, tmp, &intf->bundles, links)
1164 		gb_bundle_destroy(bundle);
1165 err_free_manifest:
1166 	kfree(manifest);
1167 err_disable_control:
1168 	gb_control_disable(intf->control);
1169 err_put_control:
1170 	gb_control_put(intf->control);
1171 	intf->control = NULL;
1172 
1173 	return ret;
1174 }
1175 
1176 /*
1177  * Disable an interface and destroy its bundles.
1178  *
1179  * Locking: Caller holds the interface mutex.
1180  */
gb_interface_disable(struct gb_interface * intf)1181 void gb_interface_disable(struct gb_interface *intf)
1182 {
1183 	struct gb_bundle *bundle;
1184 	struct gb_bundle *next;
1185 
1186 	if (!intf->enabled)
1187 		return;
1188 
1189 	trace_gb_interface_disable(intf);
1190 
1191 	pm_runtime_get_sync(&intf->dev);
1192 
1193 	/* Set disconnected flag to avoid I/O during connection tear down. */
1194 	if (intf->quirks & GB_INTERFACE_QUIRK_FORCED_DISABLE)
1195 		intf->disconnected = true;
1196 
1197 	list_for_each_entry_safe(bundle, next, &intf->bundles, links)
1198 		gb_bundle_destroy(bundle);
1199 
1200 	if (!intf->mode_switch && !intf->disconnected)
1201 		gb_control_interface_deactivate_prepare(intf->control);
1202 
1203 	gb_control_del(intf->control);
1204 	gb_control_disable(intf->control);
1205 	gb_control_put(intf->control);
1206 	intf->control = NULL;
1207 
1208 	intf->enabled = false;
1209 
1210 	pm_runtime_disable(&intf->dev);
1211 	pm_runtime_set_suspended(&intf->dev);
1212 	pm_runtime_dont_use_autosuspend(&intf->dev);
1213 	pm_runtime_put_noidle(&intf->dev);
1214 }
1215 
1216 /* Register an interface. */
gb_interface_add(struct gb_interface * intf)1217 int gb_interface_add(struct gb_interface *intf)
1218 {
1219 	int ret;
1220 
1221 	ret = device_add(&intf->dev);
1222 	if (ret) {
1223 		dev_err(&intf->dev, "failed to register interface: %d\n", ret);
1224 		return ret;
1225 	}
1226 
1227 	trace_gb_interface_add(intf);
1228 
1229 	dev_info(&intf->dev, "Interface added (%s)\n",
1230 		 gb_interface_type_string(intf));
1231 
1232 	switch (intf->type) {
1233 	case GB_INTERFACE_TYPE_GREYBUS:
1234 		dev_info(&intf->dev, "GMP VID=0x%08x, PID=0x%08x\n",
1235 			 intf->vendor_id, intf->product_id);
1236 		fallthrough;
1237 	case GB_INTERFACE_TYPE_UNIPRO:
1238 		dev_info(&intf->dev, "DDBL1 Manufacturer=0x%08x, Product=0x%08x\n",
1239 			 intf->ddbl1_manufacturer_id,
1240 			 intf->ddbl1_product_id);
1241 		break;
1242 	default:
1243 		break;
1244 	}
1245 
1246 	return 0;
1247 }
1248 
1249 /* Deregister an interface. */
gb_interface_del(struct gb_interface * intf)1250 void gb_interface_del(struct gb_interface *intf)
1251 {
1252 	if (device_is_registered(&intf->dev)) {
1253 		trace_gb_interface_del(intf);
1254 
1255 		device_del(&intf->dev);
1256 		dev_info(&intf->dev, "Interface removed\n");
1257 	}
1258 }
1259 
gb_interface_put(struct gb_interface * intf)1260 void gb_interface_put(struct gb_interface *intf)
1261 {
1262 	put_device(&intf->dev);
1263 }
1264