Line data Source code
1 : // SPDX-License-Identifier: GPL-2.0-only
2 :
3 : /*
4 : * drm_sysfs.c - Modifications to drm_sysfs_class.c to support
5 : * extra sysfs attribute from DRM. Normal drm_sysfs_class
6 : * does not allow adding attributes.
7 : *
8 : * Copyright (c) 2004 Jon Smirl <jonsmirl@gmail.com>
9 : * Copyright (c) 2003-2004 Greg Kroah-Hartman <greg@kroah.com>
10 : * Copyright (c) 2003-2004 IBM Corp.
11 : */
12 :
13 : #include <linux/acpi.h>
14 : #include <linux/device.h>
15 : #include <linux/err.h>
16 : #include <linux/export.h>
17 : #include <linux/gfp.h>
18 : #include <linux/i2c.h>
19 : #include <linux/kdev_t.h>
20 : #include <linux/slab.h>
21 :
22 : #include <drm/drm_accel.h>
23 : #include <drm/drm_connector.h>
24 : #include <drm/drm_device.h>
25 : #include <drm/drm_file.h>
26 : #include <drm/drm_modes.h>
27 : #include <drm/drm_print.h>
28 : #include <drm/drm_property.h>
29 : #include <drm/drm_sysfs.h>
30 :
31 : #include "drm_internal.h"
32 : #include "drm_crtc_internal.h"
33 :
34 : #define to_drm_minor(d) dev_get_drvdata(d)
35 : #define to_drm_connector(d) dev_get_drvdata(d)
36 :
37 : /**
38 : * DOC: overview
39 : *
40 : * DRM provides very little additional support to drivers for sysfs
41 : * interactions, beyond just all the standard stuff. Drivers who want to expose
42 : * additional sysfs properties and property groups can attach them at either
43 : * &drm_device.dev or &drm_connector.kdev.
44 : *
45 : * Registration is automatically handled when calling drm_dev_register(), or
46 : * drm_connector_register() in case of hot-plugged connectors. Unregistration is
47 : * also automatically handled by drm_dev_unregister() and
48 : * drm_connector_unregister().
49 : */
50 :
51 : static struct device_type drm_sysfs_device_minor = {
52 : .name = "drm_minor"
53 : };
54 :
55 : static struct device_type drm_sysfs_device_connector = {
56 : .name = "drm_connector",
57 : };
58 :
59 : struct class *drm_class;
60 :
61 : #ifdef CONFIG_ACPI
62 : static bool drm_connector_acpi_bus_match(struct device *dev)
63 : {
64 : return dev->type == &drm_sysfs_device_connector;
65 : }
66 :
67 : static struct acpi_device *drm_connector_acpi_find_companion(struct device *dev)
68 : {
69 : struct drm_connector *connector = to_drm_connector(dev);
70 :
71 : return to_acpi_device_node(connector->fwnode);
72 : }
73 :
74 : static struct acpi_bus_type drm_connector_acpi_bus = {
75 : .name = "drm_connector",
76 : .match = drm_connector_acpi_bus_match,
77 : .find_companion = drm_connector_acpi_find_companion,
78 : };
79 :
80 : static void drm_sysfs_acpi_register(void)
81 : {
82 : register_acpi_bus_type(&drm_connector_acpi_bus);
83 : }
84 :
85 : static void drm_sysfs_acpi_unregister(void)
86 : {
87 : unregister_acpi_bus_type(&drm_connector_acpi_bus);
88 : }
89 : #else
90 : static void drm_sysfs_acpi_register(void) { }
91 : static void drm_sysfs_acpi_unregister(void) { }
92 : #endif
93 :
94 2 : static char *drm_devnode(const struct device *dev, umode_t *mode)
95 : {
96 2 : return kasprintf(GFP_KERNEL, "dri/%s", dev_name(dev));
97 : }
98 :
99 : static CLASS_ATTR_STRING(version, S_IRUGO, "drm 1.1.0 20060810");
100 :
101 : /**
102 : * drm_sysfs_init - initialize sysfs helpers
103 : *
104 : * This is used to create the DRM class, which is the implicit parent of any
105 : * other top-level DRM sysfs objects.
106 : *
107 : * You must call drm_sysfs_destroy() to release the allocated resources.
108 : *
109 : * Return: 0 on success, negative error code on failure.
110 : */
111 1 : int drm_sysfs_init(void)
112 : {
113 : int err;
114 :
115 1 : drm_class = class_create(THIS_MODULE, "drm");
116 2 : if (IS_ERR(drm_class))
117 0 : return PTR_ERR(drm_class);
118 :
119 2 : err = class_create_file(drm_class, &class_attr_version.attr);
120 1 : if (err) {
121 0 : class_destroy(drm_class);
122 0 : drm_class = NULL;
123 0 : return err;
124 : }
125 :
126 1 : drm_class->devnode = drm_devnode;
127 :
128 : drm_sysfs_acpi_register();
129 1 : return 0;
130 : }
131 :
132 : /**
133 : * drm_sysfs_destroy - destroys DRM class
134 : *
135 : * Destroy the DRM device class.
136 : */
137 0 : void drm_sysfs_destroy(void)
138 : {
139 0 : if (IS_ERR_OR_NULL(drm_class))
140 : return;
141 : drm_sysfs_acpi_unregister();
142 0 : class_remove_file(drm_class, &class_attr_version.attr);
143 0 : class_destroy(drm_class);
144 0 : drm_class = NULL;
145 : }
146 :
147 17 : static void drm_sysfs_release(struct device *dev)
148 : {
149 17 : kfree(dev);
150 17 : }
151 :
152 : /*
153 : * Connector properties
154 : */
155 0 : static ssize_t status_store(struct device *device,
156 : struct device_attribute *attr,
157 : const char *buf, size_t count)
158 : {
159 0 : struct drm_connector *connector = to_drm_connector(device);
160 0 : struct drm_device *dev = connector->dev;
161 : enum drm_connector_force old_force;
162 : int ret;
163 :
164 0 : ret = mutex_lock_interruptible(&dev->mode_config.mutex);
165 0 : if (ret)
166 0 : return ret;
167 :
168 0 : old_force = connector->force;
169 :
170 0 : if (sysfs_streq(buf, "detect"))
171 0 : connector->force = 0;
172 0 : else if (sysfs_streq(buf, "on"))
173 0 : connector->force = DRM_FORCE_ON;
174 0 : else if (sysfs_streq(buf, "on-digital"))
175 0 : connector->force = DRM_FORCE_ON_DIGITAL;
176 0 : else if (sysfs_streq(buf, "off"))
177 0 : connector->force = DRM_FORCE_OFF;
178 : else
179 : ret = -EINVAL;
180 :
181 0 : if (old_force != connector->force || !connector->force) {
182 0 : DRM_DEBUG_KMS("[CONNECTOR:%d:%s] force updated from %d to %d or reprobing\n",
183 : connector->base.id,
184 : connector->name,
185 : old_force, connector->force);
186 :
187 0 : connector->funcs->fill_modes(connector,
188 0 : dev->mode_config.max_width,
189 0 : dev->mode_config.max_height);
190 : }
191 :
192 0 : mutex_unlock(&dev->mode_config.mutex);
193 :
194 0 : return ret ? ret : count;
195 : }
196 :
197 0 : static ssize_t status_show(struct device *device,
198 : struct device_attribute *attr,
199 : char *buf)
200 : {
201 0 : struct drm_connector *connector = to_drm_connector(device);
202 : enum drm_connector_status status;
203 :
204 0 : status = READ_ONCE(connector->status);
205 :
206 0 : return sysfs_emit(buf, "%s\n",
207 : drm_get_connector_status_name(status));
208 : }
209 :
210 0 : static ssize_t dpms_show(struct device *device,
211 : struct device_attribute *attr,
212 : char *buf)
213 : {
214 0 : struct drm_connector *connector = to_drm_connector(device);
215 : int dpms;
216 :
217 0 : dpms = READ_ONCE(connector->dpms);
218 :
219 0 : return sysfs_emit(buf, "%s\n", drm_get_dpms_name(dpms));
220 : }
221 :
222 0 : static ssize_t enabled_show(struct device *device,
223 : struct device_attribute *attr,
224 : char *buf)
225 : {
226 0 : struct drm_connector *connector = to_drm_connector(device);
227 : bool enabled;
228 :
229 0 : enabled = READ_ONCE(connector->encoder);
230 :
231 0 : return sysfs_emit(buf, enabled ? "enabled\n" : "disabled\n");
232 : }
233 :
234 0 : static ssize_t edid_show(struct file *filp, struct kobject *kobj,
235 : struct bin_attribute *attr, char *buf, loff_t off,
236 : size_t count)
237 : {
238 0 : struct device *connector_dev = kobj_to_dev(kobj);
239 0 : struct drm_connector *connector = to_drm_connector(connector_dev);
240 : unsigned char *edid;
241 : size_t size;
242 0 : ssize_t ret = 0;
243 :
244 0 : mutex_lock(&connector->dev->mode_config.mutex);
245 0 : if (!connector->edid_blob_ptr)
246 : goto unlock;
247 :
248 0 : edid = connector->edid_blob_ptr->data;
249 0 : size = connector->edid_blob_ptr->length;
250 0 : if (!edid)
251 : goto unlock;
252 :
253 0 : if (off >= size)
254 : goto unlock;
255 :
256 0 : if (off + count > size)
257 0 : count = size - off;
258 0 : memcpy(buf, edid + off, count);
259 :
260 0 : ret = count;
261 : unlock:
262 0 : mutex_unlock(&connector->dev->mode_config.mutex);
263 :
264 0 : return ret;
265 : }
266 :
267 0 : static ssize_t modes_show(struct device *device,
268 : struct device_attribute *attr,
269 : char *buf)
270 : {
271 0 : struct drm_connector *connector = to_drm_connector(device);
272 : struct drm_display_mode *mode;
273 0 : int written = 0;
274 :
275 0 : mutex_lock(&connector->dev->mode_config.mutex);
276 0 : list_for_each_entry(mode, &connector->modes, head) {
277 0 : written += scnprintf(buf + written, PAGE_SIZE - written, "%s\n",
278 0 : mode->name);
279 : }
280 0 : mutex_unlock(&connector->dev->mode_config.mutex);
281 :
282 0 : return written;
283 : }
284 :
285 : static DEVICE_ATTR_RW(status);
286 : static DEVICE_ATTR_RO(enabled);
287 : static DEVICE_ATTR_RO(dpms);
288 : static DEVICE_ATTR_RO(modes);
289 :
290 : static struct attribute *connector_dev_attrs[] = {
291 : &dev_attr_status.attr,
292 : &dev_attr_enabled.attr,
293 : &dev_attr_dpms.attr,
294 : &dev_attr_modes.attr,
295 : NULL
296 : };
297 :
298 : static struct bin_attribute edid_attr = {
299 : .attr.name = "edid",
300 : .attr.mode = 0444,
301 : .size = 0,
302 : .read = edid_show,
303 : };
304 :
305 : static struct bin_attribute *connector_bin_attrs[] = {
306 : &edid_attr,
307 : NULL
308 : };
309 :
310 : static const struct attribute_group connector_dev_group = {
311 : .attrs = connector_dev_attrs,
312 : .bin_attrs = connector_bin_attrs,
313 : };
314 :
315 : static const struct attribute_group *connector_dev_groups[] = {
316 : &connector_dev_group,
317 : NULL
318 : };
319 :
320 0 : int drm_sysfs_connector_add(struct drm_connector *connector)
321 : {
322 0 : struct drm_device *dev = connector->dev;
323 : struct device *kdev;
324 : int r;
325 :
326 0 : if (connector->kdev)
327 : return 0;
328 :
329 0 : kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
330 0 : if (!kdev)
331 : return -ENOMEM;
332 :
333 0 : device_initialize(kdev);
334 0 : kdev->class = drm_class;
335 0 : kdev->type = &drm_sysfs_device_connector;
336 0 : kdev->parent = dev->primary->kdev;
337 0 : kdev->groups = connector_dev_groups;
338 0 : kdev->release = drm_sysfs_release;
339 0 : dev_set_drvdata(kdev, connector);
340 :
341 0 : r = dev_set_name(kdev, "card%d-%s", dev->primary->index, connector->name);
342 0 : if (r)
343 : goto err_free;
344 :
345 0 : DRM_DEBUG("adding \"%s\" to sysfs\n",
346 : connector->name);
347 :
348 0 : r = device_add(kdev);
349 0 : if (r) {
350 0 : drm_err(dev, "failed to register connector device: %d\n", r);
351 0 : goto err_free;
352 : }
353 :
354 0 : connector->kdev = kdev;
355 :
356 0 : if (connector->ddc)
357 0 : return sysfs_create_link(&connector->kdev->kobj,
358 : &connector->ddc->dev.kobj, "ddc");
359 : return 0;
360 :
361 : err_free:
362 0 : put_device(kdev);
363 0 : return r;
364 : }
365 :
366 0 : void drm_sysfs_connector_remove(struct drm_connector *connector)
367 : {
368 0 : if (!connector->kdev)
369 : return;
370 :
371 0 : if (connector->ddc)
372 0 : sysfs_remove_link(&connector->kdev->kobj, "ddc");
373 :
374 0 : DRM_DEBUG("removing \"%s\" from sysfs\n",
375 : connector->name);
376 :
377 0 : device_unregister(connector->kdev);
378 0 : connector->kdev = NULL;
379 : }
380 :
381 0 : void drm_sysfs_lease_event(struct drm_device *dev)
382 : {
383 0 : char *event_string = "LEASE=1";
384 0 : char *envp[] = { event_string, NULL };
385 :
386 0 : DRM_DEBUG("generating lease event\n");
387 :
388 0 : kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
389 0 : }
390 :
391 : /**
392 : * drm_sysfs_hotplug_event - generate a DRM uevent
393 : * @dev: DRM device
394 : *
395 : * Send a uevent for the DRM device specified by @dev. Currently we only
396 : * set HOTPLUG=1 in the uevent environment, but this could be expanded to
397 : * deal with other types of events.
398 : *
399 : * Any new uapi should be using the drm_sysfs_connector_status_event()
400 : * for uevents on connector status change.
401 : */
402 0 : void drm_sysfs_hotplug_event(struct drm_device *dev)
403 : {
404 0 : char *event_string = "HOTPLUG=1";
405 0 : char *envp[] = { event_string, NULL };
406 :
407 0 : DRM_DEBUG("generating hotplug event\n");
408 :
409 0 : kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
410 0 : }
411 : EXPORT_SYMBOL(drm_sysfs_hotplug_event);
412 :
413 : /**
414 : * drm_sysfs_connector_hotplug_event - generate a DRM uevent for any connector
415 : * change
416 : * @connector: connector which has changed
417 : *
418 : * Send a uevent for the DRM connector specified by @connector. This will send
419 : * a uevent with the properties HOTPLUG=1 and CONNECTOR.
420 : */
421 0 : void drm_sysfs_connector_hotplug_event(struct drm_connector *connector)
422 : {
423 0 : struct drm_device *dev = connector->dev;
424 0 : char hotplug_str[] = "HOTPLUG=1", conn_id[21];
425 0 : char *envp[] = { hotplug_str, conn_id, NULL };
426 :
427 0 : snprintf(conn_id, sizeof(conn_id),
428 : "CONNECTOR=%u", connector->base.id);
429 :
430 0 : drm_dbg_kms(connector->dev,
431 : "[CONNECTOR:%d:%s] generating connector hotplug event\n",
432 : connector->base.id, connector->name);
433 :
434 0 : kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
435 0 : }
436 : EXPORT_SYMBOL(drm_sysfs_connector_hotplug_event);
437 :
438 : /**
439 : * drm_sysfs_connector_status_event - generate a DRM uevent for connector
440 : * property status change
441 : * @connector: connector on which property status changed
442 : * @property: connector property whose status changed.
443 : *
444 : * Send a uevent for the DRM device specified by @dev. Currently we
445 : * set HOTPLUG=1 and connector id along with the attached property id
446 : * related to the status change.
447 : */
448 0 : void drm_sysfs_connector_status_event(struct drm_connector *connector,
449 : struct drm_property *property)
450 : {
451 0 : struct drm_device *dev = connector->dev;
452 0 : char hotplug_str[] = "HOTPLUG=1", conn_id[21], prop_id[21];
453 0 : char *envp[4] = { hotplug_str, conn_id, prop_id, NULL };
454 :
455 0 : WARN_ON(!drm_mode_obj_find_prop_id(&connector->base,
456 : property->base.id));
457 :
458 0 : snprintf(conn_id, ARRAY_SIZE(conn_id),
459 : "CONNECTOR=%u", connector->base.id);
460 0 : snprintf(prop_id, ARRAY_SIZE(prop_id),
461 : "PROPERTY=%u", property->base.id);
462 :
463 0 : DRM_DEBUG("generating connector status event\n");
464 :
465 0 : kobject_uevent_env(&dev->primary->kdev->kobj, KOBJ_CHANGE, envp);
466 0 : }
467 : EXPORT_SYMBOL(drm_sysfs_connector_status_event);
468 :
469 17 : struct device *drm_sysfs_minor_alloc(struct drm_minor *minor)
470 : {
471 : const char *minor_str;
472 : struct device *kdev;
473 : int r;
474 :
475 17 : kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
476 17 : if (!kdev)
477 : return ERR_PTR(-ENOMEM);
478 :
479 17 : device_initialize(kdev);
480 :
481 17 : if (minor->type == DRM_MINOR_ACCEL) {
482 : minor_str = "accel%d";
483 : accel_set_device_instance_params(kdev, minor->index);
484 : } else {
485 17 : if (minor->type == DRM_MINOR_RENDER)
486 : minor_str = "renderD%d";
487 : else
488 17 : minor_str = "card%d";
489 :
490 17 : kdev->devt = MKDEV(DRM_MAJOR, minor->index);
491 17 : kdev->class = drm_class;
492 17 : kdev->type = &drm_sysfs_device_minor;
493 : }
494 :
495 17 : kdev->parent = minor->dev->dev;
496 17 : kdev->release = drm_sysfs_release;
497 34 : dev_set_drvdata(kdev, minor);
498 :
499 17 : r = dev_set_name(kdev, minor_str, minor->index);
500 17 : if (r < 0)
501 : goto err_free;
502 :
503 : return kdev;
504 :
505 : err_free:
506 0 : put_device(kdev);
507 0 : return ERR_PTR(r);
508 : }
509 :
510 : /**
511 : * drm_class_device_register - register new device with the DRM sysfs class
512 : * @dev: device to register
513 : *
514 : * Registers a new &struct device within the DRM sysfs class. Essentially only
515 : * used by ttm to have a place for its global settings. Drivers should never use
516 : * this.
517 : */
518 0 : int drm_class_device_register(struct device *dev)
519 : {
520 0 : if (!drm_class || IS_ERR(drm_class))
521 : return -ENOENT;
522 :
523 0 : dev->class = drm_class;
524 0 : return device_register(dev);
525 : }
526 : EXPORT_SYMBOL_GPL(drm_class_device_register);
527 :
528 : /**
529 : * drm_class_device_unregister - unregister device with the DRM sysfs class
530 : * @dev: device to unregister
531 : *
532 : * Unregisters a &struct device from the DRM sysfs class. Essentially only used
533 : * by ttm to have a place for its global settings. Drivers should never use
534 : * this.
535 : */
536 0 : void drm_class_device_unregister(struct device *dev)
537 : {
538 0 : return device_unregister(dev);
539 : }
540 : EXPORT_SYMBOL_GPL(drm_class_device_unregister);
|