1 /* $NetBSD: drm_gem_framebuffer_helper.c,v 1.3 2021/12/19 09:49:17 riastradh Exp $ */
2
3 /*-
4 * Copyright (c) 2018 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Taylor R. Campbell.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: drm_gem_framebuffer_helper.c,v 1.3 2021/12/19 09:49:17 riastradh Exp $");
34
35 #include <linux/err.h>
36 #include <linux/slab.h>
37
38 #include <drm/drm_print.h>
39 #include <drm/drm_fourcc.h>
40 #include <drm/drm_framebuffer.h>
41 #include <drm/drm_gem.h>
42 #include <drm/drm_gem_framebuffer_helper.h>
43 #include <drm/drm_modeset_helper.h>
44
45 #include <uapi/drm/drm_mode.h>
46
47 /*
48 * drm_gem_fb_destroy(fb)
49 *
50 * Release the objects in, clean up and, kfree a framebuffer
51 * allocated with drm_gem_fb_create_with_funcs.
52 *
53 * Fit for use as struct drm_framebuffer_funcs::destroy. Caller
54 * must guarantee that the struct drm_framebuffer is allocated
55 * with kmalloc.
56 */
57 void
drm_gem_fb_destroy(struct drm_framebuffer * fb)58 drm_gem_fb_destroy(struct drm_framebuffer *fb)
59 {
60 unsigned plane;
61
62 for (plane = 0; plane < __arraycount(fb->obj); plane++)
63 drm_gem_object_put_unlocked(fb->obj[plane]);
64 drm_framebuffer_cleanup(fb);
65 kfree(fb);
66 }
67
68 /*
69 * drm_gem_fb_create_handle(fb, file, handlep)
70 *
71 * Create a GEM handle for the object of the first plane (plane=0)
72 * of fb in the specified drm file namespace, and store it in
73 * *handlep.
74 *
75 * Returns 0 on success, negative error on failure.
76 */
77 int
drm_gem_fb_create_handle(struct drm_framebuffer * fb,struct drm_file * file,unsigned * handlep)78 drm_gem_fb_create_handle(struct drm_framebuffer *fb, struct drm_file *file,
79 unsigned *handlep)
80 {
81
82 return drm_gem_handle_create(file, fb->obj[0], handlep);
83 }
84
85 /*
86 * drm_gem_fb_create_with_funcs(dev, file, mode_cmd, funcs)
87 *
88 * Create a framebuffer in the specified drm device from the given
89 * mode command, resolving mode_cmd's handles in the specified drm
90 * file.
91 *
92 * Returns pointer on success, ERR_PTR on failure.
93 *
94 * ENOENT missing handle
95 * EINVAL wrong size object, invalid mode format
96 */
97 struct drm_framebuffer *
drm_gem_fb_create_with_funcs(struct drm_device * dev,struct drm_file * file,const struct drm_mode_fb_cmd2 * mode_cmd,const struct drm_framebuffer_funcs * funcs)98 drm_gem_fb_create_with_funcs(struct drm_device *dev, struct drm_file *file,
99 const struct drm_mode_fb_cmd2 *mode_cmd,
100 const struct drm_framebuffer_funcs *funcs)
101 {
102 struct drm_framebuffer *fb;
103 unsigned plane;
104 int ret;
105
106 /* Allocate a framebuffer object with kmalloc. */
107 fb = kmalloc(sizeof(*fb), GFP_KERNEL);
108 if (fb == NULL) {
109 ret = -ENOMEM;
110 goto fail0;
111 }
112
113 /*
114 * Fill framebuffer parameters from mode_cmd. If they're not
115 * valid, fail with EINVAL.
116 */
117 drm_helper_mode_fill_fb_struct(dev, fb, mode_cmd);
118 if (fb->format == NULL) {
119 ret = -EINVAL;
120 goto fail1;
121 }
122
123 /* Get the object for each plane. */
124 for (plane = 0; plane < fb->format->num_planes; plane++) {
125 unsigned vsub = (plane > 0 ? fb->format->vsub : 1); /* XXX ? */
126 unsigned hsub = (plane > 0 ? fb->format->hsub : 1); /* XXX ? */
127 unsigned handle = mode_cmd->handles[plane];
128 unsigned size;
129
130 /* Look up the object for this plane. */
131 fb->obj[plane] = drm_gem_object_lookup(file, handle);
132 if (fb->obj[plane] == NULL) {
133 ret = -ENOENT;
134 goto fail2;
135 }
136
137 /* Confirm the object is large enough to handle it. */
138 size = (mode_cmd->height/vsub - 1)*mode_cmd->pitches[plane]
139 + (mode_cmd->width/hsub)*fb->format->cpp[plane]
140 + mode_cmd->offsets[plane];
141 if (fb->obj[plane]->size < size) {
142 ret = -EINVAL;
143 plane++; /* free this one too */
144 goto fail2;
145 }
146 }
147
148 /* Initialize the framebuffer. */
149 ret = drm_framebuffer_init(dev, fb, funcs);
150 if (ret)
151 goto fail2;
152
153 /* Success! */
154 return fb;
155
156 fail2: while (plane --> 0)
157 drm_gem_object_put_unlocked(fb->obj[plane]);
158 fail1: kmem_free(fb, sizeof(*fb));
159 fail0: KASSERT(ret);
160 return ERR_PTR(ret);
161 }
162