1 // SPDX-License-Identifier: GPL-2.0-only
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.
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.
13 #include <linux/device.h>
14 #include <linux/err.h>
15 #include <linux/export.h>
16 #include <linux/gfp.h>
17 #include <linux/i2c.h>
18 #include <linux/kdev_t.h>
19 #include <linux/slab.h>
21 #include <drm/drm_connector.h>
22 #include <drm/drm_device.h>
23 #include <drm/drm_file.h>
24 #include <drm/drm_modes.h>
25 #include <drm/drm_print.h>
26 #include <drm/drm_property.h>
27 #include <drm/drm_sysfs.h>
29 #include "drm_internal.h"
30 #include "drm_crtc_internal.h"
32 #define to_drm_minor(d) dev_get_drvdata(d)
33 #define to_drm_connector(d) dev_get_drvdata(d)
38 * DRM provides very little additional support to drivers for sysfs
39 * interactions, beyond just all the standard stuff. Drivers who want to expose
40 * additional sysfs properties and property groups can attach them at either
41 * &drm_device.dev or &drm_connector.kdev.
43 * Registration is automatically handled when calling drm_dev_register(), or
44 * drm_connector_register() in case of hot-plugged connectors. Unregistration is
45 * also automatically handled by drm_dev_unregister() and
46 * drm_connector_unregister().
49 static struct device_type drm_sysfs_device_minor
= {
53 struct class *drm_class
;
55 static char *drm_devnode(struct device
*dev
, umode_t
*mode
)
57 return kasprintf(GFP_KERNEL
, "dri/%s", dev_name(dev
));
60 static CLASS_ATTR_STRING(version
, S_IRUGO
, "drm 1.1.0 20060810");
63 * drm_sysfs_init - initialize sysfs helpers
65 * This is used to create the DRM class, which is the implicit parent of any
66 * other top-level DRM sysfs objects.
68 * You must call drm_sysfs_destroy() to release the allocated resources.
70 * Return: 0 on success, negative error code on failure.
72 int drm_sysfs_init(void)
76 drm_class
= class_create(THIS_MODULE
, "drm");
77 if (IS_ERR(drm_class
))
78 return PTR_ERR(drm_class
);
80 err
= class_create_file(drm_class
, &class_attr_version
.attr
);
82 class_destroy(drm_class
);
87 drm_class
->devnode
= drm_devnode
;
92 * drm_sysfs_destroy - destroys DRM class
94 * Destroy the DRM device class.
96 void drm_sysfs_destroy(void)
98 if (IS_ERR_OR_NULL(drm_class
))
100 class_remove_file(drm_class
, &class_attr_version
.attr
);
101 class_destroy(drm_class
);
106 * Connector properties
108 static ssize_t
status_store(struct device
*device
,
109 struct device_attribute
*attr
,
110 const char *buf
, size_t count
)
112 struct drm_connector
*connector
= to_drm_connector(device
);
113 struct drm_device
*dev
= connector
->dev
;
114 enum drm_connector_force old_force
;
117 ret
= mutex_lock_interruptible(&dev
->mode_config
.mutex
);
121 old_force
= connector
->force
;
123 if (sysfs_streq(buf
, "detect"))
124 connector
->force
= 0;
125 else if (sysfs_streq(buf
, "on"))
126 connector
->force
= DRM_FORCE_ON
;
127 else if (sysfs_streq(buf
, "on-digital"))
128 connector
->force
= DRM_FORCE_ON_DIGITAL
;
129 else if (sysfs_streq(buf
, "off"))
130 connector
->force
= DRM_FORCE_OFF
;
134 if (old_force
!= connector
->force
|| !connector
->force
) {
135 DRM_DEBUG_KMS("[CONNECTOR:%d:%s] force updated from %d to %d or reprobing\n",
138 old_force
, connector
->force
);
140 connector
->funcs
->fill_modes(connector
,
141 dev
->mode_config
.max_width
,
142 dev
->mode_config
.max_height
);
145 mutex_unlock(&dev
->mode_config
.mutex
);
147 return ret
? ret
: count
;
150 static ssize_t
status_show(struct device
*device
,
151 struct device_attribute
*attr
,
154 struct drm_connector
*connector
= to_drm_connector(device
);
155 enum drm_connector_status status
;
157 status
= READ_ONCE(connector
->status
);
159 return snprintf(buf
, PAGE_SIZE
, "%s\n",
160 drm_get_connector_status_name(status
));
163 static ssize_t
dpms_show(struct device
*device
,
164 struct device_attribute
*attr
,
167 struct drm_connector
*connector
= to_drm_connector(device
);
170 dpms
= READ_ONCE(connector
->dpms
);
172 return snprintf(buf
, PAGE_SIZE
, "%s\n",
173 drm_get_dpms_name(dpms
));
176 static ssize_t
enabled_show(struct device
*device
,
177 struct device_attribute
*attr
,
180 struct drm_connector
*connector
= to_drm_connector(device
);
183 enabled
= READ_ONCE(connector
->encoder
);
185 return snprintf(buf
, PAGE_SIZE
, enabled
? "enabled\n" : "disabled\n");
188 static ssize_t
edid_show(struct file
*filp
, struct kobject
*kobj
,
189 struct bin_attribute
*attr
, char *buf
, loff_t off
,
192 struct device
*connector_dev
= kobj_to_dev(kobj
);
193 struct drm_connector
*connector
= to_drm_connector(connector_dev
);
198 mutex_lock(&connector
->dev
->mode_config
.mutex
);
199 if (!connector
->edid_blob_ptr
)
202 edid
= connector
->edid_blob_ptr
->data
;
203 size
= connector
->edid_blob_ptr
->length
;
210 if (off
+ count
> size
)
212 memcpy(buf
, edid
+ off
, count
);
216 mutex_unlock(&connector
->dev
->mode_config
.mutex
);
221 static ssize_t
modes_show(struct device
*device
,
222 struct device_attribute
*attr
,
225 struct drm_connector
*connector
= to_drm_connector(device
);
226 struct drm_display_mode
*mode
;
229 mutex_lock(&connector
->dev
->mode_config
.mutex
);
230 list_for_each_entry(mode
, &connector
->modes
, head
) {
231 written
+= scnprintf(buf
+ written
, PAGE_SIZE
- written
, "%s\n",
234 mutex_unlock(&connector
->dev
->mode_config
.mutex
);
239 static DEVICE_ATTR_RW(status
);
240 static DEVICE_ATTR_RO(enabled
);
241 static DEVICE_ATTR_RO(dpms
);
242 static DEVICE_ATTR_RO(modes
);
244 static struct attribute
*connector_dev_attrs
[] = {
245 &dev_attr_status
.attr
,
246 &dev_attr_enabled
.attr
,
248 &dev_attr_modes
.attr
,
252 static struct bin_attribute edid_attr
= {
259 static struct bin_attribute
*connector_bin_attrs
[] = {
264 static const struct attribute_group connector_dev_group
= {
265 .attrs
= connector_dev_attrs
,
266 .bin_attrs
= connector_bin_attrs
,
269 static const struct attribute_group
*connector_dev_groups
[] = {
270 &connector_dev_group
,
274 int drm_sysfs_connector_add(struct drm_connector
*connector
)
276 struct drm_device
*dev
= connector
->dev
;
282 device_create_with_groups(drm_class
, dev
->primary
->kdev
, 0,
283 connector
, connector_dev_groups
,
284 "card%d-%s", dev
->primary
->index
,
286 DRM_DEBUG("adding \"%s\" to sysfs\n",
289 if (IS_ERR(connector
->kdev
)) {
290 DRM_ERROR("failed to register connector device: %ld\n", PTR_ERR(connector
->kdev
));
291 return PTR_ERR(connector
->kdev
);
294 /* Let userspace know we have a new connector */
295 drm_sysfs_hotplug_event(dev
);
298 return sysfs_create_link(&connector
->kdev
->kobj
,
299 &connector
->ddc
->dev
.kobj
, "ddc");
303 void drm_sysfs_connector_remove(struct drm_connector
*connector
)
305 if (!connector
->kdev
)
309 sysfs_remove_link(&connector
->kdev
->kobj
, "ddc");
311 DRM_DEBUG("removing \"%s\" from sysfs\n",
314 device_unregister(connector
->kdev
);
315 connector
->kdev
= NULL
;
318 void drm_sysfs_lease_event(struct drm_device
*dev
)
320 char *event_string
= "LEASE=1";
321 char *envp
[] = { event_string
, NULL
};
323 DRM_DEBUG("generating lease event\n");
325 kobject_uevent_env(&dev
->primary
->kdev
->kobj
, KOBJ_CHANGE
, envp
);
329 * drm_sysfs_hotplug_event - generate a DRM uevent
332 * Send a uevent for the DRM device specified by @dev. Currently we only
333 * set HOTPLUG=1 in the uevent environment, but this could be expanded to
334 * deal with other types of events.
336 * Any new uapi should be using the drm_sysfs_connector_status_event()
337 * for uevents on connector status change.
339 void drm_sysfs_hotplug_event(struct drm_device
*dev
)
341 char *event_string
= "HOTPLUG=1";
342 char *envp
[] = { event_string
, NULL
};
344 DRM_DEBUG("generating hotplug event\n");
346 kobject_uevent_env(&dev
->primary
->kdev
->kobj
, KOBJ_CHANGE
, envp
);
348 EXPORT_SYMBOL(drm_sysfs_hotplug_event
);
351 * drm_sysfs_connector_status_event - generate a DRM uevent for connector
352 * property status change
353 * @connector: connector on which property status changed
354 * @property: connector property whose status changed.
356 * Send a uevent for the DRM device specified by @dev. Currently we
357 * set HOTPLUG=1 and connector id along with the attached property id
358 * related to the status change.
360 void drm_sysfs_connector_status_event(struct drm_connector
*connector
,
361 struct drm_property
*property
)
363 struct drm_device
*dev
= connector
->dev
;
364 char hotplug_str
[] = "HOTPLUG=1", conn_id
[21], prop_id
[21];
365 char *envp
[4] = { hotplug_str
, conn_id
, prop_id
, NULL
};
367 WARN_ON(!drm_mode_obj_find_prop_id(&connector
->base
,
370 snprintf(conn_id
, ARRAY_SIZE(conn_id
),
371 "CONNECTOR=%u", connector
->base
.id
);
372 snprintf(prop_id
, ARRAY_SIZE(prop_id
),
373 "PROPERTY=%u", property
->base
.id
);
375 DRM_DEBUG("generating connector status event\n");
377 kobject_uevent_env(&dev
->primary
->kdev
->kobj
, KOBJ_CHANGE
, envp
);
379 EXPORT_SYMBOL(drm_sysfs_connector_status_event
);
381 static void drm_sysfs_release(struct device
*dev
)
386 struct device
*drm_sysfs_minor_alloc(struct drm_minor
*minor
)
388 const char *minor_str
;
392 if (minor
->type
== DRM_MINOR_RENDER
)
393 minor_str
= "renderD%d";
395 minor_str
= "card%d";
397 kdev
= kzalloc(sizeof(*kdev
), GFP_KERNEL
);
399 return ERR_PTR(-ENOMEM
);
401 device_initialize(kdev
);
402 kdev
->devt
= MKDEV(DRM_MAJOR
, minor
->index
);
403 kdev
->class = drm_class
;
404 kdev
->type
= &drm_sysfs_device_minor
;
405 kdev
->parent
= minor
->dev
->dev
;
406 kdev
->release
= drm_sysfs_release
;
407 dev_set_drvdata(kdev
, minor
);
409 r
= dev_set_name(kdev
, minor_str
, minor
->index
);
421 * drm_class_device_register - register new device with the DRM sysfs class
422 * @dev: device to register
424 * Registers a new &struct device within the DRM sysfs class. Essentially only
425 * used by ttm to have a place for its global settings. Drivers should never use
428 int drm_class_device_register(struct device
*dev
)
430 if (!drm_class
|| IS_ERR(drm_class
))
433 dev
->class = drm_class
;
434 return device_register(dev
);
436 EXPORT_SYMBOL_GPL(drm_class_device_register
);
439 * drm_class_device_unregister - unregister device with the DRM sysfs class
440 * @dev: device to unregister
442 * Unregisters a &struct device from the DRM sysfs class. Essentially only used
443 * by ttm to have a place for its global settings. Drivers should never use
446 void drm_class_device_unregister(struct device
*dev
)
448 return device_unregister(dev
);
450 EXPORT_SYMBOL_GPL(drm_class_device_unregister
);