xref: /linux/drivers/gpu/drm/drm_sysfs.c (revision e8d235d4d8fb8957bae5f6ed4521115203a00d8b)
1 
2 /*
3  * drm_sysfs.c - Modifications to drm_sysfs_class.c to support
4  *               extra sysfs attribute from DRM. Normal drm_sysfs_class
5  *               does not allow adding attributes.
6  *
7  * Copyright (c) 2004 Jon Smirl <jonsmirl@gmail.com>
8  * Copyright (c) 2003-2004 Greg Kroah-Hartman <greg@kroah.com>
9  * Copyright (c) 2003-2004 IBM Corp.
10  *
11  * This file is released under the GPLv2
12  *
13  */
14 
15 #include <linux/device.h>
16 #include <linux/kdev_t.h>
17 #include <linux/gfp.h>
18 #include <linux/err.h>
19 #include <linux/export.h>
20 
21 #include <drm/drm_sysfs.h>
22 #include <drm/drm_core.h>
23 #include <drm/drmP.h>
24 #include "drm_internal.h"
25 
26 #define to_drm_minor(d) dev_get_drvdata(d)
27 #define to_drm_connector(d) dev_get_drvdata(d)
28 
29 static struct device_type drm_sysfs_device_minor = {
30 	.name = "drm_minor"
31 };
32 
33 /**
34  * __drm_class_suspend - internal DRM class suspend routine
35  * @dev: Linux device to suspend
36  * @state: power state to enter
37  *
38  * Just figures out what the actual struct drm_device associated with
39  * @dev is and calls its suspend hook, if present.
40  */
41 static int __drm_class_suspend(struct device *dev, pm_message_t state)
42 {
43 	if (dev->type == &drm_sysfs_device_minor) {
44 		struct drm_minor *drm_minor = to_drm_minor(dev);
45 		struct drm_device *drm_dev = drm_minor->dev;
46 
47 		if (drm_minor->type == DRM_MINOR_LEGACY &&
48 		    !drm_core_check_feature(drm_dev, DRIVER_MODESET) &&
49 		    drm_dev->driver->suspend)
50 			return drm_dev->driver->suspend(drm_dev, state);
51 	}
52 	return 0;
53 }
54 
55 /**
56  * drm_class_suspend - internal DRM class suspend hook. Simply calls
57  * __drm_class_suspend() with the correct pm state.
58  * @dev: Linux device to suspend
59  */
60 static int drm_class_suspend(struct device *dev)
61 {
62 	return __drm_class_suspend(dev, PMSG_SUSPEND);
63 }
64 
65 /**
66  * drm_class_freeze - internal DRM class freeze hook. Simply calls
67  * __drm_class_suspend() with the correct pm state.
68  * @dev: Linux device to freeze
69  */
70 static int drm_class_freeze(struct device *dev)
71 {
72 	return __drm_class_suspend(dev, PMSG_FREEZE);
73 }
74 
75 /**
76  * drm_class_resume - DRM class resume hook
77  * @dev: Linux device to resume
78  *
79  * Just figures out what the actual struct drm_device associated with
80  * @dev is and calls its resume hook, if present.
81  */
82 static int drm_class_resume(struct device *dev)
83 {
84 	if (dev->type == &drm_sysfs_device_minor) {
85 		struct drm_minor *drm_minor = to_drm_minor(dev);
86 		struct drm_device *drm_dev = drm_minor->dev;
87 
88 		if (drm_minor->type == DRM_MINOR_LEGACY &&
89 		    !drm_core_check_feature(drm_dev, DRIVER_MODESET) &&
90 		    drm_dev->driver->resume)
91 			return drm_dev->driver->resume(drm_dev);
92 	}
93 	return 0;
94 }
95 
96 static const struct dev_pm_ops drm_class_dev_pm_ops = {
97 	.suspend	= drm_class_suspend,
98 	.resume		= drm_class_resume,
99 	.freeze		= drm_class_freeze,
100 };
101 
102 static char *drm_devnode(struct device *dev, umode_t *mode)
103 {
104 	return kasprintf(GFP_KERNEL, "dri/%s", dev_name(dev));
105 }
106 
107 static CLASS_ATTR_STRING(version, S_IRUGO,
108 		CORE_NAME " "
109 		__stringify(CORE_MAJOR) "."
110 		__stringify(CORE_MINOR) "."
111 		__stringify(CORE_PATCHLEVEL) " "
112 		CORE_DATE);
113 
114 /**
115  * drm_sysfs_create - create a struct drm_sysfs_class structure
116  * @owner: pointer to the module that is to "own" this struct drm_sysfs_class
117  * @name: pointer to a string for the name of this class.
118  *
119  * This is used to create DRM class pointer that can then be used
120  * in calls to drm_sysfs_device_add().
121  *
122  * Note, the pointer created here is to be destroyed when finished by making a
123  * call to drm_sysfs_destroy().
124  */
125 struct class *drm_sysfs_create(struct module *owner, char *name)
126 {
127 	struct class *class;
128 	int err;
129 
130 	class = class_create(owner, name);
131 	if (IS_ERR(class)) {
132 		err = PTR_ERR(class);
133 		goto err_out;
134 	}
135 
136 	class->pm = &drm_class_dev_pm_ops;
137 
138 	err = class_create_file(class, &class_attr_version.attr);
139 	if (err)
140 		goto err_out_class;
141 
142 	class->devnode = drm_devnode;
143 
144 	return class;
145 
146 err_out_class:
147 	class_destroy(class);
148 err_out:
149 	return ERR_PTR(err);
150 }
151 
152 /**
153  * drm_sysfs_destroy - destroys DRM class
154  *
155  * Destroy the DRM device class.
156  */
157 void drm_sysfs_destroy(void)
158 {
159 	if ((drm_class == NULL) || (IS_ERR(drm_class)))
160 		return;
161 	class_remove_file(drm_class, &class_attr_version.attr);
162 	class_destroy(drm_class);
163 	drm_class = NULL;
164 }
165 
166 /*
167  * Connector properties
168  */
169 static ssize_t status_store(struct device *device,
170 			   struct device_attribute *attr,
171 			   const char *buf, size_t count)
172 {
173 	struct drm_connector *connector = to_drm_connector(device);
174 	struct drm_device *dev = connector->dev;
175 	enum drm_connector_status old_status;
176 	int ret;
177 
178 	ret = mutex_lock_interruptible(&dev->mode_config.mutex);
179 	if (ret)
180 		return ret;
181 
182 	old_status = connector->status;
183 
184 	if (sysfs_streq(buf, "detect")) {
185 		connector->force = 0;
186 		connector->status = connector->funcs->detect(connector, true);
187 	} else if (sysfs_streq(buf, "on")) {
188 		connector->force = DRM_FORCE_ON;
189 	} else if (sysfs_streq(buf, "on-digital")) {
190 		connector->force = DRM_FORCE_ON_DIGITAL;
191 	} else if (sysfs_streq(buf, "off")) {
192 		connector->force = DRM_FORCE_OFF;
193 	} else
194 		ret = -EINVAL;
195 
196 	if (ret == 0 && connector->force) {
197 		if (connector->force == DRM_FORCE_ON ||
198 		    connector->force == DRM_FORCE_ON_DIGITAL)
199 			connector->status = connector_status_connected;
200 		else
201 			connector->status = connector_status_disconnected;
202 		if (connector->funcs->force)
203 			connector->funcs->force(connector);
204 	}
205 
206 	if (old_status != connector->status) {
207 		DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %d to %d\n",
208 			      connector->base.id,
209 			      connector->name,
210 			      old_status, connector->status);
211 
212 		dev->mode_config.delayed_event = true;
213 		if (dev->mode_config.poll_enabled)
214 			schedule_delayed_work(&dev->mode_config.output_poll_work,
215 					      0);
216 	}
217 
218 	mutex_unlock(&dev->mode_config.mutex);
219 
220 	return ret;
221 }
222 
223 static ssize_t status_show(struct device *device,
224 			   struct device_attribute *attr,
225 			   char *buf)
226 {
227 	struct drm_connector *connector = to_drm_connector(device);
228 
229 	return snprintf(buf, PAGE_SIZE, "%s\n",
230 			drm_get_connector_status_name(connector->status));
231 }
232 
233 static ssize_t dpms_show(struct device *device,
234 			   struct device_attribute *attr,
235 			   char *buf)
236 {
237 	struct drm_connector *connector = to_drm_connector(device);
238 	struct drm_device *dev = connector->dev;
239 	uint64_t dpms_status;
240 	int ret;
241 
242 	ret = drm_object_property_get_value(&connector->base,
243 					    dev->mode_config.dpms_property,
244 					    &dpms_status);
245 	if (ret)
246 		return 0;
247 
248 	return snprintf(buf, PAGE_SIZE, "%s\n",
249 			drm_get_dpms_name((int)dpms_status));
250 }
251 
252 static ssize_t enabled_show(struct device *device,
253 			    struct device_attribute *attr,
254 			   char *buf)
255 {
256 	struct drm_connector *connector = to_drm_connector(device);
257 
258 	return snprintf(buf, PAGE_SIZE, "%s\n", connector->encoder ? "enabled" :
259 			"disabled");
260 }
261 
262 static ssize_t edid_show(struct file *filp, struct kobject *kobj,
263 			 struct bin_attribute *attr, char *buf, loff_t off,
264 			 size_t count)
265 {
266 	struct device *connector_dev = container_of(kobj, struct device, kobj);
267 	struct drm_connector *connector = to_drm_connector(connector_dev);
268 	unsigned char *edid;
269 	size_t size;
270 
271 	if (!connector->edid_blob_ptr)
272 		return 0;
273 
274 	edid = connector->edid_blob_ptr->data;
275 	size = connector->edid_blob_ptr->length;
276 	if (!edid)
277 		return 0;
278 
279 	if (off >= size)
280 		return 0;
281 
282 	if (off + count > size)
283 		count = size - off;
284 	memcpy(buf, edid + off, count);
285 
286 	return count;
287 }
288 
289 static ssize_t modes_show(struct device *device,
290 			   struct device_attribute *attr,
291 			   char *buf)
292 {
293 	struct drm_connector *connector = to_drm_connector(device);
294 	struct drm_display_mode *mode;
295 	int written = 0;
296 
297 	list_for_each_entry(mode, &connector->modes, head) {
298 		written += snprintf(buf + written, PAGE_SIZE - written, "%s\n",
299 				    mode->name);
300 	}
301 
302 	return written;
303 }
304 
305 static ssize_t subconnector_show(struct device *device,
306 			   struct device_attribute *attr,
307 			   char *buf)
308 {
309 	struct drm_connector *connector = to_drm_connector(device);
310 	struct drm_device *dev = connector->dev;
311 	struct drm_property *prop = NULL;
312 	uint64_t subconnector;
313 	int is_tv = 0;
314 	int ret;
315 
316 	switch (connector->connector_type) {
317 		case DRM_MODE_CONNECTOR_DVII:
318 			prop = dev->mode_config.dvi_i_subconnector_property;
319 			break;
320 		case DRM_MODE_CONNECTOR_Composite:
321 		case DRM_MODE_CONNECTOR_SVIDEO:
322 		case DRM_MODE_CONNECTOR_Component:
323 		case DRM_MODE_CONNECTOR_TV:
324 			prop = dev->mode_config.tv_subconnector_property;
325 			is_tv = 1;
326 			break;
327 		default:
328 			DRM_ERROR("Wrong connector type for this property\n");
329 			return 0;
330 	}
331 
332 	if (!prop) {
333 		DRM_ERROR("Unable to find subconnector property\n");
334 		return 0;
335 	}
336 
337 	ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
338 	if (ret)
339 		return 0;
340 
341 	return snprintf(buf, PAGE_SIZE, "%s", is_tv ?
342 			drm_get_tv_subconnector_name((int)subconnector) :
343 			drm_get_dvi_i_subconnector_name((int)subconnector));
344 }
345 
346 static ssize_t select_subconnector_show(struct device *device,
347 			   struct device_attribute *attr,
348 			   char *buf)
349 {
350 	struct drm_connector *connector = to_drm_connector(device);
351 	struct drm_device *dev = connector->dev;
352 	struct drm_property *prop = NULL;
353 	uint64_t subconnector;
354 	int is_tv = 0;
355 	int ret;
356 
357 	switch (connector->connector_type) {
358 		case DRM_MODE_CONNECTOR_DVII:
359 			prop = dev->mode_config.dvi_i_select_subconnector_property;
360 			break;
361 		case DRM_MODE_CONNECTOR_Composite:
362 		case DRM_MODE_CONNECTOR_SVIDEO:
363 		case DRM_MODE_CONNECTOR_Component:
364 		case DRM_MODE_CONNECTOR_TV:
365 			prop = dev->mode_config.tv_select_subconnector_property;
366 			is_tv = 1;
367 			break;
368 		default:
369 			DRM_ERROR("Wrong connector type for this property\n");
370 			return 0;
371 	}
372 
373 	if (!prop) {
374 		DRM_ERROR("Unable to find select subconnector property\n");
375 		return 0;
376 	}
377 
378 	ret = drm_object_property_get_value(&connector->base, prop, &subconnector);
379 	if (ret)
380 		return 0;
381 
382 	return snprintf(buf, PAGE_SIZE, "%s", is_tv ?
383 			drm_get_tv_select_name((int)subconnector) :
384 			drm_get_dvi_i_select_name((int)subconnector));
385 }
386 
387 static DEVICE_ATTR_RW(status);
388 static DEVICE_ATTR_RO(enabled);
389 static DEVICE_ATTR_RO(dpms);
390 static DEVICE_ATTR_RO(modes);
391 
392 static struct attribute *connector_dev_attrs[] = {
393 	&dev_attr_status.attr,
394 	&dev_attr_enabled.attr,
395 	&dev_attr_dpms.attr,
396 	&dev_attr_modes.attr,
397 	NULL
398 };
399 
400 /* These attributes are for both DVI-I connectors and all types of tv-out. */
401 static DEVICE_ATTR_RO(subconnector);
402 static DEVICE_ATTR_RO(select_subconnector);
403 
404 static struct attribute *connector_opt_dev_attrs[] = {
405 	&dev_attr_subconnector.attr,
406 	&dev_attr_select_subconnector.attr,
407 	NULL
408 };
409 
410 static umode_t connector_opt_dev_is_visible(struct kobject *kobj,
411 					    struct attribute *attr, int idx)
412 {
413 	struct device *dev = kobj_to_dev(kobj);
414 	struct drm_connector *connector = to_drm_connector(dev);
415 
416 	/*
417 	 * In the long run it maybe a good idea to make one set of
418 	 * optionals per connector type.
419 	 */
420 	switch (connector->connector_type) {
421 	case DRM_MODE_CONNECTOR_DVII:
422 	case DRM_MODE_CONNECTOR_Composite:
423 	case DRM_MODE_CONNECTOR_SVIDEO:
424 	case DRM_MODE_CONNECTOR_Component:
425 	case DRM_MODE_CONNECTOR_TV:
426 		return attr->mode;
427 	}
428 
429 	return 0;
430 }
431 
432 static struct bin_attribute edid_attr = {
433 	.attr.name = "edid",
434 	.attr.mode = 0444,
435 	.size = 0,
436 	.read = edid_show,
437 };
438 
439 static struct bin_attribute *connector_bin_attrs[] = {
440 	&edid_attr,
441 	NULL
442 };
443 
444 static const struct attribute_group connector_dev_group = {
445 	.attrs = connector_dev_attrs,
446 	.bin_attrs = connector_bin_attrs,
447 };
448 
449 static const struct attribute_group connector_opt_dev_group = {
450 	.attrs = connector_opt_dev_attrs,
451 	.is_visible = connector_opt_dev_is_visible,
452 };
453 
454 static const struct attribute_group *connector_dev_groups[] = {
455 	&connector_dev_group,
456 	&connector_opt_dev_group,
457 	NULL
458 };
459 
460 /**
461  * drm_sysfs_connector_add - add a connector to sysfs
462  * @connector: connector to add
463  *
464  * Create a connector device in sysfs, along with its associated connector
465  * properties (so far, connection status, dpms, mode list & edid) and
466  * generate a hotplug event so userspace knows there's a new connector
467  * available.
468  */
469 int drm_sysfs_connector_add(struct drm_connector *connector)
470 {
471 	struct drm_device *dev = connector->dev;
472 
473 	if (connector->kdev)
474 		return 0;
475 
476 	connector->kdev =
477 		device_create_with_groups(drm_class, dev->primary->kdev, 0,
478 					  connector, connector_dev_groups,
479 					  "card%d-%s", dev->primary->index,
480 					  connector->name);
481 	DRM_DEBUG("adding \"%s\" to sysfs\n",
482 		  connector->name);
483 
484 	if (IS_ERR(connector->kdev)) {
485 		DRM_ERROR("failed to register connector device: %ld\n", PTR_ERR(connector->kdev));
486 		return PTR_ERR(connector->kdev);
487 	}
488 
489 	/* Let userspace know we have a new connector */
490 	drm_sysfs_hotplug_event(dev);
491 
492 	return 0;
493 }
494 
495 /**
496  * drm_sysfs_connector_remove - remove an connector device from sysfs
497  * @connector: connector to remove
498  *
499  * Remove @connector and its associated attributes from sysfs.  Note that
500  * the device model core will take care of sending the "remove" uevent
501  * at this time, so we don't need to do it.
502  *
503  * Note:
504  * This routine should only be called if the connector was previously
505  * successfully registered.  If @connector hasn't been registered yet,
506  * you'll likely see a panic somewhere deep in sysfs code when called.
507  */
508 void drm_sysfs_connector_remove(struct drm_connector *connector)
509 {
510 	if (!connector->kdev)
511 		return;
512 	DRM_DEBUG("removing \"%s\" from sysfs\n",
513 		  connector->name);
514 
515 	device_unregister(connector->kdev);
516 	connector->kdev = NULL;
517 }
518 
519 /**
520  * drm_sysfs_hotplug_event - generate a DRM uevent
521  * @dev: DRM device
522  *
523  * Send a uevent for the DRM device specified by @dev.  Currently we only
524  * set HOTPLUG=1 in the uevent environment, but this could be expanded to
525  * deal with other types of events.
526  */
527 void drm_sysfs_hotplug_event(struct drm_device *dev)
528 {
529 	char *event_string = "HOTPLUG=1";
530 	char *envp[] = { event_string, NULL };
531 
532 	DRM_DEBUG("generating hotplug event\n");
533 
534 	kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
535 }
536 EXPORT_SYMBOL(drm_sysfs_hotplug_event);
537 
538 static void drm_sysfs_release(struct device *dev)
539 {
540 	kfree(dev);
541 }
542 
543 /**
544  * drm_sysfs_minor_alloc() - Allocate sysfs device for given minor
545  * @minor: minor to allocate sysfs device for
546  *
547  * This allocates a new sysfs device for @minor and returns it. The device is
548  * not registered nor linked. The caller has to use device_add() and
549  * device_del() to register and unregister it.
550  *
551  * Note that dev_get_drvdata() on the new device will return the minor.
552  * However, the device does not hold a ref-count to the minor nor to the
553  * underlying drm_device. This is unproblematic as long as you access the
554  * private data only in sysfs callbacks. device_del() disables those
555  * synchronously, so they cannot be called after you cleanup a minor.
556  */
557 struct device *drm_sysfs_minor_alloc(struct drm_minor *minor)
558 {
559 	const char *minor_str;
560 	struct device *kdev;
561 	int r;
562 
563 	if (minor->type == DRM_MINOR_CONTROL)
564 		minor_str = "controlD%d";
565 	else if (minor->type == DRM_MINOR_RENDER)
566 		minor_str = "renderD%d";
567 	else
568 		minor_str = "card%d";
569 
570 	kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
571 	if (!kdev)
572 		return ERR_PTR(-ENOMEM);
573 
574 	device_initialize(kdev);
575 	kdev->devt = MKDEV(DRM_MAJOR, minor->index);
576 	kdev->class = drm_class;
577 	kdev->type = &drm_sysfs_device_minor;
578 	kdev->parent = minor->dev->dev;
579 	kdev->release = drm_sysfs_release;
580 	dev_set_drvdata(kdev, minor);
581 
582 	r = dev_set_name(kdev, minor_str, minor->index);
583 	if (r < 0)
584 		goto err_free;
585 
586 	return kdev;
587 
588 err_free:
589 	put_device(kdev);
590 	return ERR_PTR(r);
591 }
592 
593 /**
594  * drm_class_device_register - Register a struct device in the drm class.
595  *
596  * @dev: pointer to struct device to register.
597  *
598  * @dev should have all relevant members pre-filled with the exception
599  * of the class member. In particular, the device_type member must
600  * be set.
601  */
602 
603 int drm_class_device_register(struct device *dev)
604 {
605 	if (!drm_class || IS_ERR(drm_class))
606 		return -ENOENT;
607 
608 	dev->class = drm_class;
609 	return device_register(dev);
610 }
611 EXPORT_SYMBOL_GPL(drm_class_device_register);
612 
613 void drm_class_device_unregister(struct device *dev)
614 {
615 	return device_unregister(dev);
616 }
617 EXPORT_SYMBOL_GPL(drm_class_device_unregister);
618