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_sysfs.h"
22 #include "drm_core.h"
23 #include "drmP.h"
24 
25 #define to_drm_minor(d) container_of(d, struct drm_minor, kdev)
26 #define to_drm_connector(d) container_of(d, struct drm_connector, kdev)
27 
28 static struct device_type drm_sysfs_device_minor = {
29 	.name = "drm_minor"
30 };
31 
32 /**
33  * drm_class_suspend - DRM class suspend hook
34  * @dev: Linux device to suspend
35  * @state: power state to enter
36  *
37  * Just figures out what the actual struct drm_device associated with
38  * @dev is and calls its suspend hook, if present.
39  */
drm_class_suspend(struct device * dev,pm_message_t state)40 static int drm_class_suspend(struct device *dev, pm_message_t state)
41 {
42 	if (dev->type == &drm_sysfs_device_minor) {
43 		struct drm_minor *drm_minor = to_drm_minor(dev);
44 		struct drm_device *drm_dev = drm_minor->dev;
45 
46 		if (drm_minor->type == DRM_MINOR_LEGACY &&
47 		    !drm_core_check_feature(drm_dev, DRIVER_MODESET) &&
48 		    drm_dev->driver->suspend)
49 			return drm_dev->driver->suspend(drm_dev, state);
50 	}
51 	return 0;
52 }
53 
54 /**
55  * drm_class_resume - DRM class resume hook
56  * @dev: Linux device to resume
57  *
58  * Just figures out what the actual struct drm_device associated with
59  * @dev is and calls its resume hook, if present.
60  */
drm_class_resume(struct device * dev)61 static int drm_class_resume(struct device *dev)
62 {
63 	if (dev->type == &drm_sysfs_device_minor) {
64 		struct drm_minor *drm_minor = to_drm_minor(dev);
65 		struct drm_device *drm_dev = drm_minor->dev;
66 
67 		if (drm_minor->type == DRM_MINOR_LEGACY &&
68 		    !drm_core_check_feature(drm_dev, DRIVER_MODESET) &&
69 		    drm_dev->driver->resume)
70 			return drm_dev->driver->resume(drm_dev);
71 	}
72 	return 0;
73 }
74 
drm_devnode(struct device * dev,umode_t * mode)75 static char *drm_devnode(struct device *dev, umode_t *mode)
76 {
77 	return kasprintf(GFP_KERNEL, "dri/%s", dev_name(dev));
78 }
79 
80 static CLASS_ATTR_STRING(version, S_IRUGO,
81 		CORE_NAME " "
82 		__stringify(CORE_MAJOR) "."
83 		__stringify(CORE_MINOR) "."
84 		__stringify(CORE_PATCHLEVEL) " "
85 		CORE_DATE);
86 
87 /**
88  * drm_sysfs_create - create a struct drm_sysfs_class structure
89  * @owner: pointer to the module that is to "own" this struct drm_sysfs_class
90  * @name: pointer to a string for the name of this class.
91  *
92  * This is used to create DRM class pointer that can then be used
93  * in calls to drm_sysfs_device_add().
94  *
95  * Note, the pointer created here is to be destroyed when finished by making a
96  * call to drm_sysfs_destroy().
97  */
drm_sysfs_create(struct module * owner,char * name)98 struct class *drm_sysfs_create(struct module *owner, char *name)
99 {
100 	struct class *class;
101 	int err;
102 
103 	class = class_create(owner, name);
104 	if (IS_ERR(class)) {
105 		err = PTR_ERR(class);
106 		goto err_out;
107 	}
108 
109 	class->suspend = drm_class_suspend;
110 	class->resume = drm_class_resume;
111 
112 	err = class_create_file(class, &class_attr_version.attr);
113 	if (err)
114 		goto err_out_class;
115 
116 	class->devnode = drm_devnode;
117 
118 	return class;
119 
120 err_out_class:
121 	class_destroy(class);
122 err_out:
123 	return ERR_PTR(err);
124 }
125 
126 /**
127  * drm_sysfs_destroy - destroys DRM class
128  *
129  * Destroy the DRM device class.
130  */
drm_sysfs_destroy(void)131 void drm_sysfs_destroy(void)
132 {
133 	if ((drm_class == NULL) || (IS_ERR(drm_class)))
134 		return;
135 	class_remove_file(drm_class, &class_attr_version.attr);
136 	class_destroy(drm_class);
137 }
138 
139 /**
140  * drm_sysfs_device_release - do nothing
141  * @dev: Linux device
142  *
143  * Normally, this would free the DRM device associated with @dev, along
144  * with cleaning up any other stuff.  But we do that in the DRM core, so
145  * this function can just return and hope that the core does its job.
146  */
drm_sysfs_device_release(struct device * dev)147 static void drm_sysfs_device_release(struct device *dev)
148 {
149 	memset(dev, 0, sizeof(struct device));
150 	return;
151 }
152 
153 /*
154  * Connector properties
155  */
status_show(struct device * device,struct device_attribute * attr,char * buf)156 static ssize_t status_show(struct device *device,
157 			   struct device_attribute *attr,
158 			   char *buf)
159 {
160 	struct drm_connector *connector = to_drm_connector(device);
161 	enum drm_connector_status status;
162 	int ret;
163 
164 	ret = mutex_lock_interruptible(&connector->dev->mode_config.mutex);
165 	if (ret)
166 		return ret;
167 
168 	status = connector->funcs->detect(connector, true);
169 	mutex_unlock(&connector->dev->mode_config.mutex);
170 
171 	return snprintf(buf, PAGE_SIZE, "%s\n",
172 			drm_get_connector_status_name(status));
173 }
174 
dpms_show(struct device * device,struct device_attribute * attr,char * buf)175 static ssize_t dpms_show(struct device *device,
176 			   struct device_attribute *attr,
177 			   char *buf)
178 {
179 	struct drm_connector *connector = to_drm_connector(device);
180 	struct drm_device *dev = connector->dev;
181 	uint64_t dpms_status;
182 	int ret;
183 
184 	ret = drm_connector_property_get_value(connector,
185 					    dev->mode_config.dpms_property,
186 					    &dpms_status);
187 	if (ret)
188 		return 0;
189 
190 	return snprintf(buf, PAGE_SIZE, "%s\n",
191 			drm_get_dpms_name((int)dpms_status));
192 }
193 
enabled_show(struct device * device,struct device_attribute * attr,char * buf)194 static ssize_t enabled_show(struct device *device,
195 			    struct device_attribute *attr,
196 			   char *buf)
197 {
198 	struct drm_connector *connector = to_drm_connector(device);
199 
200 	return snprintf(buf, PAGE_SIZE, "%s\n", connector->encoder ? "enabled" :
201 			"disabled");
202 }
203 
edid_show(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)204 static ssize_t edid_show(struct file *filp, struct kobject *kobj,
205 			 struct bin_attribute *attr, char *buf, loff_t off,
206 			 size_t count)
207 {
208 	struct device *connector_dev = container_of(kobj, struct device, kobj);
209 	struct drm_connector *connector = to_drm_connector(connector_dev);
210 	unsigned char *edid;
211 	size_t size;
212 
213 	if (!connector->edid_blob_ptr)
214 		return 0;
215 
216 	edid = connector->edid_blob_ptr->data;
217 	size = connector->edid_blob_ptr->length;
218 	if (!edid)
219 		return 0;
220 
221 	if (off >= size)
222 		return 0;
223 
224 	if (off + count > size)
225 		count = size - off;
226 	memcpy(buf, edid + off, count);
227 
228 	return count;
229 }
230 
modes_show(struct device * device,struct device_attribute * attr,char * buf)231 static ssize_t modes_show(struct device *device,
232 			   struct device_attribute *attr,
233 			   char *buf)
234 {
235 	struct drm_connector *connector = to_drm_connector(device);
236 	struct drm_display_mode *mode;
237 	int written = 0;
238 
239 	list_for_each_entry(mode, &connector->modes, head) {
240 		written += snprintf(buf + written, PAGE_SIZE - written, "%s\n",
241 				    mode->name);
242 	}
243 
244 	return written;
245 }
246 
subconnector_show(struct device * device,struct device_attribute * attr,char * buf)247 static ssize_t subconnector_show(struct device *device,
248 			   struct device_attribute *attr,
249 			   char *buf)
250 {
251 	struct drm_connector *connector = to_drm_connector(device);
252 	struct drm_device *dev = connector->dev;
253 	struct drm_property *prop = NULL;
254 	uint64_t subconnector;
255 	int is_tv = 0;
256 	int ret;
257 
258 	switch (connector->connector_type) {
259 		case DRM_MODE_CONNECTOR_DVII:
260 			prop = dev->mode_config.dvi_i_subconnector_property;
261 			break;
262 		case DRM_MODE_CONNECTOR_Composite:
263 		case DRM_MODE_CONNECTOR_SVIDEO:
264 		case DRM_MODE_CONNECTOR_Component:
265 		case DRM_MODE_CONNECTOR_TV:
266 			prop = dev->mode_config.tv_subconnector_property;
267 			is_tv = 1;
268 			break;
269 		default:
270 			DRM_ERROR("Wrong connector type for this property\n");
271 			return 0;
272 	}
273 
274 	if (!prop) {
275 		DRM_ERROR("Unable to find subconnector property\n");
276 		return 0;
277 	}
278 
279 	ret = drm_connector_property_get_value(connector, prop, &subconnector);
280 	if (ret)
281 		return 0;
282 
283 	return snprintf(buf, PAGE_SIZE, "%s", is_tv ?
284 			drm_get_tv_subconnector_name((int)subconnector) :
285 			drm_get_dvi_i_subconnector_name((int)subconnector));
286 }
287 
select_subconnector_show(struct device * device,struct device_attribute * attr,char * buf)288 static ssize_t select_subconnector_show(struct device *device,
289 			   struct device_attribute *attr,
290 			   char *buf)
291 {
292 	struct drm_connector *connector = to_drm_connector(device);
293 	struct drm_device *dev = connector->dev;
294 	struct drm_property *prop = NULL;
295 	uint64_t subconnector;
296 	int is_tv = 0;
297 	int ret;
298 
299 	switch (connector->connector_type) {
300 		case DRM_MODE_CONNECTOR_DVII:
301 			prop = dev->mode_config.dvi_i_select_subconnector_property;
302 			break;
303 		case DRM_MODE_CONNECTOR_Composite:
304 		case DRM_MODE_CONNECTOR_SVIDEO:
305 		case DRM_MODE_CONNECTOR_Component:
306 		case DRM_MODE_CONNECTOR_TV:
307 			prop = dev->mode_config.tv_select_subconnector_property;
308 			is_tv = 1;
309 			break;
310 		default:
311 			DRM_ERROR("Wrong connector type for this property\n");
312 			return 0;
313 	}
314 
315 	if (!prop) {
316 		DRM_ERROR("Unable to find select subconnector property\n");
317 		return 0;
318 	}
319 
320 	ret = drm_connector_property_get_value(connector, prop, &subconnector);
321 	if (ret)
322 		return 0;
323 
324 	return snprintf(buf, PAGE_SIZE, "%s", is_tv ?
325 			drm_get_tv_select_name((int)subconnector) :
326 			drm_get_dvi_i_select_name((int)subconnector));
327 }
328 
329 static struct device_attribute connector_attrs[] = {
330 	__ATTR_RO(status),
331 	__ATTR_RO(enabled),
332 	__ATTR_RO(dpms),
333 	__ATTR_RO(modes),
334 };
335 
336 /* These attributes are for both DVI-I connectors and all types of tv-out. */
337 static struct device_attribute connector_attrs_opt1[] = {
338 	__ATTR_RO(subconnector),
339 	__ATTR_RO(select_subconnector),
340 };
341 
342 static struct bin_attribute edid_attr = {
343 	.attr.name = "edid",
344 	.attr.mode = 0444,
345 	.size = 0,
346 	.read = edid_show,
347 };
348 
349 /**
350  * drm_sysfs_connector_add - add an connector to sysfs
351  * @connector: connector to add
352  *
353  * Create an connector device in sysfs, along with its associated connector
354  * properties (so far, connection status, dpms, mode list & edid) and
355  * generate a hotplug event so userspace knows there's a new connector
356  * available.
357  *
358  * Note:
359  * This routine should only be called *once* for each DRM minor registered.
360  * A second call for an already registered device will trigger the BUG_ON
361  * below.
362  */
drm_sysfs_connector_add(struct drm_connector * connector)363 int drm_sysfs_connector_add(struct drm_connector *connector)
364 {
365 	struct drm_device *dev = connector->dev;
366 	int attr_cnt = 0;
367 	int opt_cnt = 0;
368 	int i;
369 	int ret = 0;
370 
371 	/* We shouldn't get called more than once for the same connector */
372 	BUG_ON(device_is_registered(&connector->kdev));
373 
374 	connector->kdev.parent = &dev->primary->kdev;
375 	connector->kdev.class = drm_class;
376 	connector->kdev.release = drm_sysfs_device_release;
377 
378 	DRM_DEBUG("adding \"%s\" to sysfs\n",
379 		  drm_get_connector_name(connector));
380 
381 	dev_set_name(&connector->kdev, "card%d-%s",
382 		     dev->primary->index, drm_get_connector_name(connector));
383 	ret = device_register(&connector->kdev);
384 
385 	if (ret) {
386 		DRM_ERROR("failed to register connector device: %d\n", ret);
387 		goto out;
388 	}
389 
390 	/* Standard attributes */
391 
392 	for (attr_cnt = 0; attr_cnt < ARRAY_SIZE(connector_attrs); attr_cnt++) {
393 		ret = device_create_file(&connector->kdev, &connector_attrs[attr_cnt]);
394 		if (ret)
395 			goto err_out_files;
396 	}
397 
398 	/* Optional attributes */
399 	/*
400 	 * In the long run it maybe a good idea to make one set of
401 	 * optionals per connector type.
402 	 */
403 	switch (connector->connector_type) {
404 		case DRM_MODE_CONNECTOR_DVII:
405 		case DRM_MODE_CONNECTOR_Composite:
406 		case DRM_MODE_CONNECTOR_SVIDEO:
407 		case DRM_MODE_CONNECTOR_Component:
408 		case DRM_MODE_CONNECTOR_TV:
409 			for (opt_cnt = 0; opt_cnt < ARRAY_SIZE(connector_attrs_opt1); opt_cnt++) {
410 				ret = device_create_file(&connector->kdev, &connector_attrs_opt1[opt_cnt]);
411 				if (ret)
412 					goto err_out_files;
413 			}
414 			break;
415 		default:
416 			break;
417 	}
418 
419 	ret = sysfs_create_bin_file(&connector->kdev.kobj, &edid_attr);
420 	if (ret)
421 		goto err_out_files;
422 
423 	/* Let userspace know we have a new connector */
424 	drm_sysfs_hotplug_event(dev);
425 
426 	return 0;
427 
428 err_out_files:
429 	for (i = 0; i < opt_cnt; i++)
430 		device_remove_file(&connector->kdev, &connector_attrs_opt1[i]);
431 	for (i = 0; i < attr_cnt; i++)
432 		device_remove_file(&connector->kdev, &connector_attrs[i]);
433 	device_unregister(&connector->kdev);
434 
435 out:
436 	return ret;
437 }
438 EXPORT_SYMBOL(drm_sysfs_connector_add);
439 
440 /**
441  * drm_sysfs_connector_remove - remove an connector device from sysfs
442  * @connector: connector to remove
443  *
444  * Remove @connector and its associated attributes from sysfs.  Note that
445  * the device model core will take care of sending the "remove" uevent
446  * at this time, so we don't need to do it.
447  *
448  * Note:
449  * This routine should only be called if the connector was previously
450  * successfully registered.  If @connector hasn't been registered yet,
451  * you'll likely see a panic somewhere deep in sysfs code when called.
452  */
drm_sysfs_connector_remove(struct drm_connector * connector)453 void drm_sysfs_connector_remove(struct drm_connector *connector)
454 {
455 	int i;
456 
457 	if (!connector->kdev.parent)
458 		return;
459 	DRM_DEBUG("removing \"%s\" from sysfs\n",
460 		  drm_get_connector_name(connector));
461 
462 	for (i = 0; i < ARRAY_SIZE(connector_attrs); i++)
463 		device_remove_file(&connector->kdev, &connector_attrs[i]);
464 	sysfs_remove_bin_file(&connector->kdev.kobj, &edid_attr);
465 	device_unregister(&connector->kdev);
466 	connector->kdev.parent = NULL;
467 }
468 EXPORT_SYMBOL(drm_sysfs_connector_remove);
469 
470 /**
471  * drm_sysfs_hotplug_event - generate a DRM uevent
472  * @dev: DRM device
473  *
474  * Send a uevent for the DRM device specified by @dev.  Currently we only
475  * set HOTPLUG=1 in the uevent environment, but this could be expanded to
476  * deal with other types of events.
477  */
drm_sysfs_hotplug_event(struct drm_device * dev)478 void drm_sysfs_hotplug_event(struct drm_device *dev)
479 {
480 	char *event_string = "HOTPLUG=1";
481 	char *envp[] = { event_string, NULL };
482 
483 	DRM_DEBUG("generating hotplug event\n");
484 
485 	kobject_uevent_env(&dev->primary->kdev.kobj, KOBJ_CHANGE, envp);
486 }
487 EXPORT_SYMBOL(drm_sysfs_hotplug_event);
488 
489 /**
490  * drm_sysfs_device_add - adds a class device to sysfs for a character driver
491  * @dev: DRM device to be added
492  * @head: DRM head in question
493  *
494  * Add a DRM device to the DRM's device model class.  We use @dev's PCI device
495  * as the parent for the Linux device, and make sure it has a file containing
496  * the driver we're using (for userspace compatibility).
497  */
drm_sysfs_device_add(struct drm_minor * minor)498 int drm_sysfs_device_add(struct drm_minor *minor)
499 {
500 	int err;
501 	char *minor_str;
502 
503 	minor->kdev.parent = minor->dev->dev;
504 
505 	minor->kdev.class = drm_class;
506 	minor->kdev.release = drm_sysfs_device_release;
507 	minor->kdev.devt = minor->device;
508 	minor->kdev.type = &drm_sysfs_device_minor;
509 	if (minor->type == DRM_MINOR_CONTROL)
510 		minor_str = "controlD%d";
511         else if (minor->type == DRM_MINOR_RENDER)
512                 minor_str = "renderD%d";
513         else
514                 minor_str = "card%d";
515 
516 	dev_set_name(&minor->kdev, minor_str, minor->index);
517 
518 	err = device_register(&minor->kdev);
519 	if (err) {
520 		DRM_ERROR("device add failed: %d\n", err);
521 		goto err_out;
522 	}
523 
524 	return 0;
525 
526 err_out:
527 	return err;
528 }
529 
530 /**
531  * drm_sysfs_device_remove - remove DRM device
532  * @dev: DRM device to remove
533  *
534  * This call unregisters and cleans up a class device that was created with a
535  * call to drm_sysfs_device_add()
536  */
drm_sysfs_device_remove(struct drm_minor * minor)537 void drm_sysfs_device_remove(struct drm_minor *minor)
538 {
539 	if (minor->kdev.parent)
540 		device_unregister(&minor->kdev);
541 	minor->kdev.parent = NULL;
542 }
543 
544 
545 /**
546  * drm_class_device_register - Register a struct device in the drm class.
547  *
548  * @dev: pointer to struct device to register.
549  *
550  * @dev should have all relevant members pre-filled with the exception
551  * of the class member. In particular, the device_type member must
552  * be set.
553  */
554 
drm_class_device_register(struct device * dev)555 int drm_class_device_register(struct device *dev)
556 {
557 	dev->class = drm_class;
558 	return device_register(dev);
559 }
560 EXPORT_SYMBOL_GPL(drm_class_device_register);
561 
drm_class_device_unregister(struct device * dev)562 void drm_class_device_unregister(struct device *dev)
563 {
564 	return device_unregister(dev);
565 }
566 EXPORT_SYMBOL_GPL(drm_class_device_unregister);
567