xref: /linux-5.15/drivers/gpu/drm/nouveau/nouveau_backlight.c (revision 868c522b1b75fd3fd3e6a636b4c344ac08edf13a)
1 /*
2  * Copyright (C) 2009 Red Hat <mjg@redhat.com>
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining
5  * a copy of this software and associated documentation files (the
6  * "Software"), to deal in the Software without restriction, including
7  * without limitation the rights to use, copy, modify, merge, publish,
8  * distribute, sublicense, and/or sell copies of the Software, and to
9  * permit persons to whom the Software is furnished to do so, subject to
10  * the following conditions:
11  *
12  * The above copyright notice and this permission notice (including the
13  * next paragraph) shall be included in all copies or substantial
14  * portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
19  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
20  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
22  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23  *
24  */
25 
26 /*
27  * Authors:
28  *  Matthew Garrett <mjg@redhat.com>
29  *
30  * Register locations derived from NVClock by Roderick Colenbrander
31  */
32 
33 #include <linux/backlight.h>
34 
35 #include "drmP.h"
36 #include "nouveau_drv.h"
37 #include "nouveau_drm.h"
38 #include "nouveau_reg.h"
39 
40 static int nv40_get_intensity(struct backlight_device *bd)
41 {
42 	struct drm_device *dev = bl_get_data(bd);
43 	int val = (nv_rd32(dev, NV40_PMC_BACKLIGHT) & NV40_PMC_BACKLIGHT_MASK)
44 									>> 16;
45 
46 	return val;
47 }
48 
49 static int nv40_set_intensity(struct backlight_device *bd)
50 {
51 	struct drm_device *dev = bl_get_data(bd);
52 	int val = bd->props.brightness;
53 	int reg = nv_rd32(dev, NV40_PMC_BACKLIGHT);
54 
55 	nv_wr32(dev, NV40_PMC_BACKLIGHT,
56 		 (val << 16) | (reg & ~NV40_PMC_BACKLIGHT_MASK));
57 
58 	return 0;
59 }
60 
61 static struct backlight_ops nv40_bl_ops = {
62 	.options = BL_CORE_SUSPENDRESUME,
63 	.get_brightness = nv40_get_intensity,
64 	.update_status = nv40_set_intensity,
65 };
66 
67 static int nv50_get_intensity(struct backlight_device *bd)
68 {
69 	struct drm_device *dev = bl_get_data(bd);
70 
71 	return nv_rd32(dev, NV50_PDISPLAY_SOR_BACKLIGHT);
72 }
73 
74 static int nv50_set_intensity(struct backlight_device *bd)
75 {
76 	struct drm_device *dev = bl_get_data(bd);
77 	int val = bd->props.brightness;
78 
79 	nv_wr32(dev, NV50_PDISPLAY_SOR_BACKLIGHT,
80 		val | NV50_PDISPLAY_SOR_BACKLIGHT_ENABLE);
81 	return 0;
82 }
83 
84 static struct backlight_ops nv50_bl_ops = {
85 	.options = BL_CORE_SUSPENDRESUME,
86 	.get_brightness = nv50_get_intensity,
87 	.update_status = nv50_set_intensity,
88 };
89 
90 static int nouveau_nv40_backlight_init(struct drm_device *dev)
91 {
92 	struct backlight_properties props;
93 	struct drm_nouveau_private *dev_priv = dev->dev_private;
94 	struct backlight_device *bd;
95 
96 	if (!(nv_rd32(dev, NV40_PMC_BACKLIGHT) & NV40_PMC_BACKLIGHT_MASK))
97 		return 0;
98 
99 	memset(&props, 0, sizeof(struct backlight_properties));
100 	props.max_brightness = 31;
101 	bd = backlight_device_register("nv_backlight", &dev->pdev->dev, dev,
102 				       &nv40_bl_ops, &props);
103 	if (IS_ERR(bd))
104 		return PTR_ERR(bd);
105 
106 	dev_priv->backlight = bd;
107 	bd->props.brightness = nv40_get_intensity(bd);
108 	backlight_update_status(bd);
109 
110 	return 0;
111 }
112 
113 static int nouveau_nv50_backlight_init(struct drm_device *dev)
114 {
115 	struct backlight_properties props;
116 	struct drm_nouveau_private *dev_priv = dev->dev_private;
117 	struct backlight_device *bd;
118 
119 	if (!nv_rd32(dev, NV50_PDISPLAY_SOR_BACKLIGHT))
120 		return 0;
121 
122 	memset(&props, 0, sizeof(struct backlight_properties));
123 	props.max_brightness = 1025;
124 	bd = backlight_device_register("nv_backlight", &dev->pdev->dev, dev,
125 				       &nv50_bl_ops, &props);
126 	if (IS_ERR(bd))
127 		return PTR_ERR(bd);
128 
129 	dev_priv->backlight = bd;
130 	bd->props.brightness = nv50_get_intensity(bd);
131 	backlight_update_status(bd);
132 	return 0;
133 }
134 
135 int nouveau_backlight_init(struct drm_device *dev)
136 {
137 	struct drm_nouveau_private *dev_priv = dev->dev_private;
138 
139 	switch (dev_priv->card_type) {
140 	case NV_40:
141 		return nouveau_nv40_backlight_init(dev);
142 	case NV_50:
143 		return nouveau_nv50_backlight_init(dev);
144 	default:
145 		break;
146 	}
147 
148 	return 0;
149 }
150 
151 void nouveau_backlight_exit(struct drm_device *dev)
152 {
153 	struct drm_nouveau_private *dev_priv = dev->dev_private;
154 
155 	if (dev_priv->backlight) {
156 		backlight_device_unregister(dev_priv->backlight);
157 		dev_priv->backlight = NULL;
158 	}
159 }
160