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/err.h>
18
19#include "drm_core.h"
20#include "drmP.h"
21
22/* Display the version of drm_core. This doesn't work right in current design */
23static ssize_t version_show(struct class *dev, char *buf)
24{
25	return sprintf(buf, "%s %d.%d.%d %s\n", CORE_NAME, CORE_MAJOR,
26		       CORE_MINOR, CORE_PATCHLEVEL, CORE_DATE);
27}
28
29static CLASS_ATTR(version, S_IRUGO, version_show, NULL);
30
31/**
32 * drm_sysfs_create - create a struct drm_sysfs_class structure
33 * @owner: pointer to the module that is to "own" this struct drm_sysfs_class
34 * @name: pointer to a string for the name of this class.
35 *
36 * This is used to create a struct drm_sysfs_class pointer that can then be used
37 * in calls to drm_sysfs_device_add().
38 *
39 * Note, the pointer created here is to be destroyed when finished by making a
40 * call to drm_sysfs_destroy().
41 */
42struct class *drm_sysfs_create(struct module *owner, char *name)
43{
44	struct class *class;
45	int err;
46
47	class = class_create(owner, name);
48	if (IS_ERR(class)) {
49		err = PTR_ERR(class);
50		goto err_out;
51	}
52
53	err = class_create_file(class, &class_attr_version);
54	if (err)
55		goto err_out_class;
56
57	return class;
58
59err_out_class:
60	class_destroy(class);
61err_out:
62	return ERR_PTR(err);
63}
64
65/**
66 * drm_sysfs_destroy - destroys a struct drm_sysfs_class structure
67 * @cs: pointer to the struct drm_sysfs_class that is to be destroyed
68 *
69 * Note, the pointer to be destroyed must have been created with a call to
70 * drm_sysfs_create().
71 */
72void drm_sysfs_destroy(struct class *class)
73{
74	if ((class == NULL) || (IS_ERR(class)))
75		return;
76
77	class_remove_file(class, &class_attr_version);
78	class_destroy(class);
79}
80
81static ssize_t show_dri(struct class_device *class_device, char *buf)
82{
83	drm_device_t * dev = ((drm_head_t *)class_get_devdata(class_device))->dev;
84	if (dev->driver->dri_library_name)
85		return dev->driver->dri_library_name(dev, buf);
86	return snprintf(buf, PAGE_SIZE, "%s\n", dev->driver->pci_driver.name);
87}
88
89static struct class_device_attribute class_device_attrs[] = {
90	__ATTR(dri_library_name, S_IRUGO, show_dri, NULL),
91};
92
93/**
94 * drm_sysfs_device_add - adds a class device to sysfs for a character driver
95 * @cs: pointer to the struct class that this device should be registered to.
96 * @dev: the dev_t for the device to be added.
97 * @device: a pointer to a struct device that is assiociated with this class device.
98 * @fmt: string for the class device's name
99 *
100 * A struct class_device will be created in sysfs, registered to the specified
101 * class.  A "dev" file will be created, showing the dev_t for the device.  The
102 * pointer to the struct class_device will be returned from the call.  Any further
103 * sysfs files that might be required can be created using this pointer.
104 * Note: the struct class passed to this function must have previously been
105 * created with a call to drm_sysfs_create().
106 */
107struct class_device *drm_sysfs_device_add(struct class *cs, drm_head_t *head)
108{
109	struct class_device *class_dev;
110	int i, j, err;
111
112	class_dev = class_device_create(cs, NULL,
113					MKDEV(DRM_MAJOR, head->minor),
114					&(head->dev->pdev)->dev,
115					"card%d", head->minor);
116	if (IS_ERR(class_dev)) {
117		err = PTR_ERR(class_dev);
118		goto err_out;
119	}
120
121	class_set_devdata(class_dev, head);
122
123	for (i = 0; i < ARRAY_SIZE(class_device_attrs); i++) {
124		err = class_device_create_file(class_dev,
125					       &class_device_attrs[i]);
126		if (err)
127			goto err_out_files;
128	}
129
130	return class_dev;
131
132err_out_files:
133	if (i > 0)
134		for (j = 0; j < i; j++)
135			class_device_remove_file(class_dev,
136						 &class_device_attrs[i]);
137	class_device_unregister(class_dev);
138err_out:
139	return ERR_PTR(err);
140}
141
142/**
143 * drm_sysfs_device_remove - removes a class device that was created with drm_sysfs_device_add()
144 * @dev: the dev_t of the device that was previously registered.
145 *
146 * This call unregisters and cleans up a class device that was created with a
147 * call to drm_sysfs_device_add()
148 */
149void drm_sysfs_device_remove(struct class_device *class_dev)
150{
151	int i;
152
153	for (i = 0; i < ARRAY_SIZE(class_device_attrs); i++)
154		class_device_remove_file(class_dev, &class_device_attrs[i]);
155	class_device_unregister(class_dev);
156}
157