Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1// SPDX-License-Identifier: MIT
2
3#include <drm/drm_client.h>
4#include <drm/drm_crtc_helper.h>
5#include <drm/drm_drv.h>
6#include <drm/drm_fb_helper.h>
7#include <drm/drm_fourcc.h>
8#include <drm/drm_print.h>
9
10#include "drm_client_internal.h"
11
12/*
13 * struct drm_client_funcs
14 */
15
16static void drm_fbdev_client_unregister(struct drm_client_dev *client)
17{
18 struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
19
20 if (fb_helper->info) {
21 drm_fb_helper_unregister_info(fb_helper);
22 } else {
23 drm_client_release(&fb_helper->client);
24 drm_fb_helper_unprepare(fb_helper);
25 kfree(fb_helper);
26 }
27}
28
29static int drm_fbdev_client_restore(struct drm_client_dev *client)
30{
31 drm_fb_helper_lastclose(client->dev);
32
33 return 0;
34}
35
36static int drm_fbdev_client_hotplug(struct drm_client_dev *client)
37{
38 struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
39 struct drm_device *dev = client->dev;
40 int ret;
41
42 if (dev->fb_helper)
43 return drm_fb_helper_hotplug_event(dev->fb_helper);
44
45 ret = drm_fb_helper_init(dev, fb_helper);
46 if (ret)
47 goto err_drm_err;
48
49 if (!drm_drv_uses_atomic_modeset(dev))
50 drm_helper_disable_unused_functions(dev);
51
52 ret = drm_fb_helper_initial_config(fb_helper);
53 if (ret)
54 goto err_drm_fb_helper_fini;
55
56 return 0;
57
58err_drm_fb_helper_fini:
59 drm_fb_helper_fini(fb_helper);
60err_drm_err:
61 drm_err(dev, "fbdev: Failed to setup emulation (ret=%d)\n", ret);
62 return ret;
63}
64
65static int drm_fbdev_client_suspend(struct drm_client_dev *client, bool holds_console_lock)
66{
67 struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
68
69 if (holds_console_lock)
70 drm_fb_helper_set_suspend(fb_helper, true);
71 else
72 drm_fb_helper_set_suspend_unlocked(fb_helper, true);
73
74 return 0;
75}
76
77static int drm_fbdev_client_resume(struct drm_client_dev *client, bool holds_console_lock)
78{
79 struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
80
81 if (holds_console_lock)
82 drm_fb_helper_set_suspend(fb_helper, false);
83 else
84 drm_fb_helper_set_suspend_unlocked(fb_helper, false);
85
86 return 0;
87}
88
89static const struct drm_client_funcs drm_fbdev_client_funcs = {
90 .owner = THIS_MODULE,
91 .unregister = drm_fbdev_client_unregister,
92 .restore = drm_fbdev_client_restore,
93 .hotplug = drm_fbdev_client_hotplug,
94 .suspend = drm_fbdev_client_suspend,
95 .resume = drm_fbdev_client_resume,
96};
97
98/**
99 * drm_fbdev_client_setup() - Setup fbdev emulation
100 * @dev: DRM device
101 * @format: Preferred color format for the device. DRM_FORMAT_XRGB8888
102 * is used if this is zero.
103 *
104 * This function sets up fbdev emulation. Restore, hotplug events and
105 * teardown are all taken care of. Drivers that do suspend/resume need
106 * to call drm_client_dev_suspend() and drm_client_dev_resume() by
107 * themselves. Simple drivers might use drm_mode_config_helper_suspend().
108 *
109 * This function is safe to call even when there are no connectors present.
110 * Setup will be retried on the next hotplug event.
111 *
112 * The fbdev client is destroyed by drm_dev_unregister().
113 *
114 * Returns:
115 * 0 on success, or a negative errno code otherwise.
116 */
117int drm_fbdev_client_setup(struct drm_device *dev, const struct drm_format_info *format)
118{
119 struct drm_fb_helper *fb_helper;
120 unsigned int color_mode;
121 int ret;
122
123 /* TODO: Use format info throughout DRM */
124 if (format) {
125 unsigned int bpp = drm_format_info_bpp(format, 0);
126
127 switch (bpp) {
128 case 16:
129 color_mode = format->depth; // could also be 15
130 break;
131 default:
132 color_mode = bpp;
133 }
134 } else {
135 switch (dev->mode_config.preferred_depth) {
136 case 0:
137 case 24:
138 color_mode = 32;
139 break;
140 default:
141 color_mode = dev->mode_config.preferred_depth;
142 }
143 }
144
145 drm_WARN(dev, !dev->registered, "Device has not been registered.\n");
146 drm_WARN(dev, dev->fb_helper, "fb_helper is already set!\n");
147
148 fb_helper = kzalloc(sizeof(*fb_helper), GFP_KERNEL);
149 if (!fb_helper)
150 return -ENOMEM;
151 drm_fb_helper_prepare(dev, fb_helper, color_mode, NULL);
152
153 ret = drm_client_init(dev, &fb_helper->client, "fbdev", &drm_fbdev_client_funcs);
154 if (ret) {
155 drm_err(dev, "Failed to register client: %d\n", ret);
156 goto err_drm_client_init;
157 }
158
159 drm_client_register(&fb_helper->client);
160
161 return 0;
162
163err_drm_client_init:
164 drm_fb_helper_unprepare(fb_helper);
165 kfree(fb_helper);
166 return ret;
167}