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/component.h>
15#include <linux/device.h>
16#include <linux/err.h>
17#include <linux/export.h>
18#include <linux/gfp.h>
19#include <linux/i2c.h>
20#include <linux/kdev_t.h>
21#include <linux/pci.h>
22#include <linux/property.h>
23#include <linux/slab.h>
24
25#include <drm/drm_accel.h>
26#include <drm/drm_connector.h>
27#include <drm/drm_device.h>
28#include <drm/drm_file.h>
29#include <drm/drm_modes.h>
30#include <drm/drm_print.h>
31#include <drm/drm_property.h>
32#include <drm/drm_sysfs.h>
33
34#include <asm/video.h>
35
36#include "drm_internal.h"
37#include "drm_crtc_internal.h"
38
39#define to_drm_minor(d) dev_get_drvdata(d)
40#define to_drm_connector(d) dev_get_drvdata(d)
41
42/**
43 * DOC: overview
44 *
45 * DRM provides very little additional support to drivers for sysfs
46 * interactions, beyond just all the standard stuff. Drivers who want to expose
47 * additional sysfs properties and property groups can attach them at either
48 * &drm_device.dev or &drm_connector.kdev.
49 *
50 * Registration is automatically handled when calling drm_dev_register(), or
51 * drm_connector_register() in case of hot-plugged connectors. Unregistration is
52 * also automatically handled by drm_dev_unregister() and
53 * drm_connector_unregister().
54 */
55
56static struct device_type drm_sysfs_device_minor = {
57 .name = "drm_minor"
58};
59
60static struct device_type drm_sysfs_device_connector = {
61 .name = "drm_connector",
62};
63
64struct class *drm_class;
65
66#ifdef CONFIG_ACPI
67static bool drm_connector_acpi_bus_match(struct device *dev)
68{
69 return dev->type == &drm_sysfs_device_connector;
70}
71
72static struct acpi_device *drm_connector_acpi_find_companion(struct device *dev)
73{
74 struct drm_connector *connector = to_drm_connector(dev);
75
76 return to_acpi_device_node(connector->fwnode);
77}
78
79static struct acpi_bus_type drm_connector_acpi_bus = {
80 .name = "drm_connector",
81 .match = drm_connector_acpi_bus_match,
82 .find_companion = drm_connector_acpi_find_companion,
83};
84
85static void drm_sysfs_acpi_register(void)
86{
87 register_acpi_bus_type(&drm_connector_acpi_bus);
88}
89
90static void drm_sysfs_acpi_unregister(void)
91{
92 unregister_acpi_bus_type(&drm_connector_acpi_bus);
93}
94#else
95static void drm_sysfs_acpi_register(void) { }
96static void drm_sysfs_acpi_unregister(void) { }
97#endif
98
99static char *drm_devnode(const struct device *dev, umode_t *mode)
100{
101 return kasprintf(GFP_KERNEL, fmt: "dri/%s", dev_name(dev));
102}
103
104static int typec_connector_bind(struct device *dev,
105 struct device *typec_connector, void *data)
106{
107 int ret;
108
109 ret = sysfs_create_link(kobj: &dev->kobj, target: &typec_connector->kobj, name: "typec_connector");
110 if (ret)
111 return ret;
112
113 ret = sysfs_create_link(kobj: &typec_connector->kobj, target: &dev->kobj, name: "drm_connector");
114 if (ret)
115 sysfs_remove_link(kobj: &dev->kobj, name: "typec_connector");
116
117 return ret;
118}
119
120static void typec_connector_unbind(struct device *dev,
121 struct device *typec_connector, void *data)
122{
123 sysfs_remove_link(kobj: &typec_connector->kobj, name: "drm_connector");
124 sysfs_remove_link(kobj: &dev->kobj, name: "typec_connector");
125}
126
127static const struct component_ops typec_connector_ops = {
128 .bind = typec_connector_bind,
129 .unbind = typec_connector_unbind,
130};
131
132static CLASS_ATTR_STRING(version, S_IRUGO, "drm 1.1.0 20060810");
133
134/**
135 * drm_sysfs_init - initialize sysfs helpers
136 *
137 * This is used to create the DRM class, which is the implicit parent of any
138 * other top-level DRM sysfs objects.
139 *
140 * You must call drm_sysfs_destroy() to release the allocated resources.
141 *
142 * Return: 0 on success, negative error code on failure.
143 */
144int drm_sysfs_init(void)
145{
146 int err;
147
148 drm_class = class_create(name: "drm");
149 if (IS_ERR(ptr: drm_class))
150 return PTR_ERR(ptr: drm_class);
151
152 err = class_create_file(class: drm_class, attr: &class_attr_version.attr);
153 if (err) {
154 class_destroy(cls: drm_class);
155 drm_class = NULL;
156 return err;
157 }
158
159 drm_class->devnode = drm_devnode;
160
161 drm_sysfs_acpi_register();
162 return 0;
163}
164
165/**
166 * drm_sysfs_destroy - destroys DRM class
167 *
168 * Destroy the DRM device class.
169 */
170void drm_sysfs_destroy(void)
171{
172 if (IS_ERR_OR_NULL(ptr: drm_class))
173 return;
174 drm_sysfs_acpi_unregister();
175 class_remove_file(class: drm_class, attr: &class_attr_version.attr);
176 class_destroy(cls: drm_class);
177 drm_class = NULL;
178}
179
180static void drm_sysfs_release(struct device *dev)
181{
182 kfree(objp: dev);
183}
184
185/*
186 * Connector properties
187 */
188static ssize_t status_store(struct device *device,
189 struct device_attribute *attr,
190 const char *buf, size_t count)
191{
192 struct drm_connector *connector = to_drm_connector(device);
193 struct drm_device *dev = connector->dev;
194 enum drm_connector_force old_force;
195 int ret;
196
197 ret = mutex_lock_interruptible(&dev->mode_config.mutex);
198 if (ret)
199 return ret;
200
201 old_force = connector->force;
202
203 if (sysfs_streq(s1: buf, s2: "detect"))
204 connector->force = 0;
205 else if (sysfs_streq(s1: buf, s2: "on"))
206 connector->force = DRM_FORCE_ON;
207 else if (sysfs_streq(s1: buf, s2: "on-digital"))
208 connector->force = DRM_FORCE_ON_DIGITAL;
209 else if (sysfs_streq(s1: buf, s2: "off"))
210 connector->force = DRM_FORCE_OFF;
211 else
212 ret = -EINVAL;
213
214 if (old_force != connector->force || !connector->force) {
215 drm_dbg_kms(dev, "[CONNECTOR:%d:%s] force updated from %d to %d or reprobing\n",
216 connector->base.id, connector->name,
217 old_force, connector->force);
218
219 connector->funcs->fill_modes(connector,
220 dev->mode_config.max_width,
221 dev->mode_config.max_height);
222 }
223
224 mutex_unlock(lock: &dev->mode_config.mutex);
225
226 return ret ? ret : count;
227}
228
229static ssize_t status_show(struct device *device,
230 struct device_attribute *attr,
231 char *buf)
232{
233 struct drm_connector *connector = to_drm_connector(device);
234 enum drm_connector_status status;
235
236 status = READ_ONCE(connector->status);
237
238 return sysfs_emit(buf, fmt: "%s\n",
239 drm_get_connector_status_name(status));
240}
241
242static ssize_t dpms_show(struct device *device,
243 struct device_attribute *attr,
244 char *buf)
245{
246 struct drm_connector *connector = to_drm_connector(device);
247 int dpms;
248
249 dpms = READ_ONCE(connector->dpms);
250
251 return sysfs_emit(buf, fmt: "%s\n", drm_get_dpms_name(val: dpms));
252}
253
254static ssize_t enabled_show(struct device *device,
255 struct device_attribute *attr,
256 char *buf)
257{
258 struct drm_connector *connector = to_drm_connector(device);
259 bool enabled;
260
261 enabled = READ_ONCE(connector->encoder);
262
263 return sysfs_emit(buf, fmt: enabled ? "enabled\n" : "disabled\n");
264}
265
266static ssize_t edid_show(struct file *filp, struct kobject *kobj,
267 const struct bin_attribute *attr, char *buf, loff_t off,
268 size_t count)
269{
270 struct device *connector_dev = kobj_to_dev(kobj);
271 struct drm_connector *connector = to_drm_connector(connector_dev);
272 ssize_t ret;
273
274 ret = drm_edid_connector_property_show(connector, buf, off, count);
275
276 return ret;
277}
278
279static ssize_t modes_show(struct device *device,
280 struct device_attribute *attr,
281 char *buf)
282{
283 struct drm_connector *connector = to_drm_connector(device);
284 struct drm_display_mode *mode;
285 int written = 0;
286
287 mutex_lock(&connector->dev->mode_config.mutex);
288 list_for_each_entry(mode, &connector->modes, head) {
289 written += scnprintf(buf: buf + written, PAGE_SIZE - written, fmt: "%s\n",
290 mode->name);
291 }
292 mutex_unlock(lock: &connector->dev->mode_config.mutex);
293
294 return written;
295}
296
297static ssize_t connector_id_show(struct device *device,
298 struct device_attribute *attr,
299 char *buf)
300{
301 struct drm_connector *connector = to_drm_connector(device);
302
303 return sysfs_emit(buf, fmt: "%d\n", connector->base.id);
304}
305
306static DEVICE_ATTR_RW(status);
307static DEVICE_ATTR_RO(enabled);
308static DEVICE_ATTR_RO(dpms);
309static DEVICE_ATTR_RO(modes);
310static DEVICE_ATTR_RO(connector_id);
311
312static struct attribute *connector_dev_attrs[] = {
313 &dev_attr_status.attr,
314 &dev_attr_enabled.attr,
315 &dev_attr_dpms.attr,
316 &dev_attr_modes.attr,
317 &dev_attr_connector_id.attr,
318 NULL
319};
320
321static const struct bin_attribute edid_attr = {
322 .attr.name = "edid",
323 .attr.mode = 0444,
324 .size = 0,
325 .read = edid_show,
326};
327
328static const struct bin_attribute *const connector_bin_attrs[] = {
329 &edid_attr,
330 NULL
331};
332
333static const struct attribute_group connector_dev_group = {
334 .attrs = connector_dev_attrs,
335 .bin_attrs = connector_bin_attrs,
336};
337
338static const struct attribute_group *connector_dev_groups[] = {
339 &connector_dev_group,
340 NULL
341};
342
343int drm_sysfs_connector_add(struct drm_connector *connector)
344{
345 struct drm_device *dev = connector->dev;
346 struct device *kdev;
347 int r;
348
349 if (connector->kdev)
350 return 0;
351
352 kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
353 if (!kdev)
354 return -ENOMEM;
355
356 device_initialize(dev: kdev);
357 kdev->class = drm_class;
358 kdev->type = &drm_sysfs_device_connector;
359 kdev->parent = dev->primary->kdev;
360 kdev->groups = connector_dev_groups;
361 kdev->release = drm_sysfs_release;
362 dev_set_drvdata(dev: kdev, data: connector);
363
364 r = dev_set_name(dev: kdev, name: "card%d-%s", dev->primary->index, connector->name);
365 if (r)
366 goto err_free;
367
368 drm_dbg_kms(dev, "[CONNECTOR:%d:%s] adding connector to sysfs\n",
369 connector->base.id, connector->name);
370
371 r = device_add(dev: kdev);
372 if (r) {
373 drm_err(dev, "failed to register connector device: %d\n", r);
374 goto err_free;
375 }
376
377 connector->kdev = kdev;
378
379 if (dev_fwnode(kdev)) {
380 r = component_add(kdev, &typec_connector_ops);
381 if (r)
382 drm_err(dev, "failed to add component to create link to typec connector\n");
383 }
384
385 return 0;
386
387err_free:
388 put_device(dev: kdev);
389 return r;
390}
391
392int drm_sysfs_connector_add_late(struct drm_connector *connector)
393{
394 if (connector->ddc)
395 return sysfs_create_link(kobj: &connector->kdev->kobj,
396 target: &connector->ddc->dev.kobj, name: "ddc");
397
398 return 0;
399}
400
401void drm_sysfs_connector_remove_early(struct drm_connector *connector)
402{
403 if (connector->ddc)
404 sysfs_remove_link(kobj: &connector->kdev->kobj, name: "ddc");
405}
406
407void drm_sysfs_connector_remove(struct drm_connector *connector)
408{
409 if (!connector->kdev)
410 return;
411
412 if (dev_fwnode(connector->kdev))
413 component_del(connector->kdev, &typec_connector_ops);
414
415 drm_dbg_kms(connector->dev,
416 "[CONNECTOR:%d:%s] removing connector from sysfs\n",
417 connector->base.id, connector->name);
418
419 device_unregister(dev: connector->kdev);
420 connector->kdev = NULL;
421}
422
423void drm_sysfs_lease_event(struct drm_device *dev)
424{
425 char *event_string = "LEASE=1";
426 char *envp[] = { event_string, NULL };
427
428 drm_dbg_lease(dev, "generating lease event\n");
429
430 kobject_uevent_env(kobj: &dev->primary->kdev->kobj, action: KOBJ_CHANGE, envp);
431}
432
433/**
434 * drm_sysfs_hotplug_event - generate a DRM uevent
435 * @dev: DRM device
436 *
437 * Send a uevent for the DRM device specified by @dev. Currently we only
438 * set HOTPLUG=1 in the uevent environment, but this could be expanded to
439 * deal with other types of events.
440 *
441 * Any new uapi should be using the drm_sysfs_connector_status_event()
442 * for uevents on connector status change.
443 */
444void drm_sysfs_hotplug_event(struct drm_device *dev)
445{
446 char *event_string = "HOTPLUG=1";
447 char *envp[] = { event_string, NULL };
448
449 drm_dbg_kms(dev, "generating hotplug event\n");
450
451 kobject_uevent_env(kobj: &dev->primary->kdev->kobj, action: KOBJ_CHANGE, envp);
452}
453EXPORT_SYMBOL(drm_sysfs_hotplug_event);
454
455/**
456 * drm_sysfs_connector_hotplug_event - generate a DRM uevent for any connector
457 * change
458 * @connector: connector which has changed
459 *
460 * Send a uevent for the DRM connector specified by @connector. This will send
461 * a uevent with the properties HOTPLUG=1 and CONNECTOR.
462 */
463void drm_sysfs_connector_hotplug_event(struct drm_connector *connector)
464{
465 struct drm_device *dev = connector->dev;
466 char hotplug_str[] = "HOTPLUG=1", conn_id[21];
467 char *envp[] = { hotplug_str, conn_id, NULL };
468
469 snprintf(buf: conn_id, size: sizeof(conn_id),
470 fmt: "CONNECTOR=%u", connector->base.id);
471
472 drm_dbg_kms(connector->dev,
473 "[CONNECTOR:%d:%s] generating connector hotplug event\n",
474 connector->base.id, connector->name);
475
476 kobject_uevent_env(kobj: &dev->primary->kdev->kobj, action: KOBJ_CHANGE, envp);
477}
478EXPORT_SYMBOL(drm_sysfs_connector_hotplug_event);
479
480/**
481 * drm_sysfs_connector_property_event - generate a DRM uevent for connector
482 * property change
483 * @connector: connector on which property changed
484 * @property: connector property which has changed.
485 *
486 * Send a uevent for the specified DRM connector and property. Currently we
487 * set HOTPLUG=1 and connector id along with the attached property id
488 * related to the change.
489 */
490void drm_sysfs_connector_property_event(struct drm_connector *connector,
491 struct drm_property *property)
492{
493 struct drm_device *dev = connector->dev;
494 char hotplug_str[] = "HOTPLUG=1", conn_id[21], prop_id[21];
495 char *envp[4] = { hotplug_str, conn_id, prop_id, NULL };
496
497 WARN_ON(!drm_mode_obj_find_prop_id(&connector->base,
498 property->base.id));
499
500 snprintf(buf: conn_id, ARRAY_SIZE(conn_id),
501 fmt: "CONNECTOR=%u", connector->base.id);
502 snprintf(buf: prop_id, ARRAY_SIZE(prop_id),
503 fmt: "PROPERTY=%u", property->base.id);
504
505 drm_dbg_kms(connector->dev,
506 "[CONNECTOR:%d:%s] generating connector property event for [PROP:%d:%s]\n",
507 connector->base.id, connector->name,
508 property->base.id, property->name);
509
510 kobject_uevent_env(kobj: &dev->primary->kdev->kobj, action: KOBJ_CHANGE, envp);
511}
512EXPORT_SYMBOL(drm_sysfs_connector_property_event);
513
514static ssize_t boot_display_show(struct device *dev, struct device_attribute *attr,
515 char *buf)
516{
517 return sysfs_emit(buf, fmt: "1\n");
518}
519static DEVICE_ATTR_RO(boot_display);
520
521static struct attribute *display_attrs[] = {
522 &dev_attr_boot_display.attr,
523 NULL
524};
525
526static umode_t boot_display_visible(struct kobject *kobj,
527 struct attribute *a, int n)
528{
529 struct device *dev = kobj_to_dev(kobj)->parent;
530
531 if (dev_is_pci(dev)) {
532 struct pci_dev *pdev = to_pci_dev(dev);
533
534 if (video_is_primary_device(dev: &pdev->dev))
535 return a->mode;
536 }
537
538 return 0;
539}
540
541static const struct attribute_group display_attr_group = {
542 .attrs = display_attrs,
543 .is_visible = boot_display_visible,
544};
545
546static const struct attribute_group *card_dev_groups[] = {
547 &display_attr_group,
548 NULL
549};
550
551struct device *drm_sysfs_minor_alloc(struct drm_minor *minor)
552{
553 const char *minor_str;
554 struct device *kdev;
555 int r;
556
557 kdev = kzalloc(sizeof(*kdev), GFP_KERNEL);
558 if (!kdev)
559 return ERR_PTR(error: -ENOMEM);
560
561 device_initialize(dev: kdev);
562
563 if (minor->type == DRM_MINOR_ACCEL) {
564 minor_str = "accel%d";
565 accel_set_device_instance_params(kdev, index: minor->index);
566 } else {
567 if (minor->type == DRM_MINOR_RENDER)
568 minor_str = "renderD%d";
569 else
570 minor_str = "card%d";
571
572 kdev->devt = MKDEV(DRM_MAJOR, minor->index);
573 kdev->class = drm_class;
574 kdev->groups = card_dev_groups;
575 kdev->type = &drm_sysfs_device_minor;
576 }
577
578 kdev->parent = minor->dev->dev;
579 kdev->release = drm_sysfs_release;
580 dev_set_drvdata(dev: kdev, data: minor);
581
582 r = dev_set_name(dev: kdev, name: minor_str, minor->index);
583 if (r < 0)
584 goto err_free;
585
586 return kdev;
587
588err_free:
589 put_device(dev: kdev);
590 return ERR_PTR(error: r);
591}
592
593/**
594 * drm_class_device_register - register new device with the DRM sysfs class
595 * @dev: device to register
596 *
597 * Registers a new &struct device within the DRM sysfs class. Essentially only
598 * used by ttm to have a place for its global settings. Drivers should never use
599 * this.
600 */
601int drm_class_device_register(struct device *dev)
602{
603 if (!drm_class || IS_ERR(ptr: drm_class))
604 return -ENOENT;
605
606 dev->class = drm_class;
607 return device_register(dev);
608}
609EXPORT_SYMBOL_GPL(drm_class_device_register);
610
611/**
612 * drm_class_device_unregister - unregister device with the DRM sysfs class
613 * @dev: device to unregister
614 *
615 * Unregisters a &struct device from the DRM sysfs class. Essentially only used
616 * by ttm to have a place for its global settings. Drivers should never use
617 * this.
618 */
619void drm_class_device_unregister(struct device *dev)
620{
621 return device_unregister(dev);
622}
623EXPORT_SYMBOL_GPL(drm_class_device_unregister);
624

source code of linux/drivers/gpu/drm/drm_sysfs.c