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 #include <linux/acpi.h>
35 
36 #include "drmP.h"
37 #include "nouveau_drv.h"
38 #include "nouveau_drm.h"
39 #include "nouveau_reg.h"
40 
41 static int nv40_get_intensity(struct backlight_device *bd)
42 {
43 	struct drm_device *dev = bl_get_data(bd);
44 	int val = (nv_rd32(dev, NV40_PMC_BACKLIGHT) & NV40_PMC_BACKLIGHT_MASK)
45 									>> 16;
46 
47 	return val;
48 }
49 
50 static int nv40_set_intensity(struct backlight_device *bd)
51 {
52 	struct drm_device *dev = bl_get_data(bd);
53 	int val = bd->props.brightness;
54 	int reg = nv_rd32(dev, NV40_PMC_BACKLIGHT);
55 
56 	nv_wr32(dev, NV40_PMC_BACKLIGHT,
57 		 (val << 16) | (reg & ~NV40_PMC_BACKLIGHT_MASK));
58 
59 	return 0;
60 }
61 
62 static const struct backlight_ops nv40_bl_ops = {
63 	.options = BL_CORE_SUSPENDRESUME,
64 	.get_brightness = nv40_get_intensity,
65 	.update_status = nv40_set_intensity,
66 };
67 
68 static int nv50_get_intensity(struct backlight_device *bd)
69 {
70 	struct drm_device *dev = bl_get_data(bd);
71 
72 	return nv_rd32(dev, NV50_PDISPLAY_SOR_BACKLIGHT);
73 }
74 
75 static int nv50_set_intensity(struct backlight_device *bd)
76 {
77 	struct drm_device *dev = bl_get_data(bd);
78 	int val = bd->props.brightness;
79 
80 	nv_wr32(dev, NV50_PDISPLAY_SOR_BACKLIGHT,
81 		val | NV50_PDISPLAY_SOR_BACKLIGHT_ENABLE);
82 	return 0;
83 }
84 
85 static const struct backlight_ops nv50_bl_ops = {
86 	.options = BL_CORE_SUSPENDRESUME,
87 	.get_brightness = nv50_get_intensity,
88 	.update_status = nv50_set_intensity,
89 };
90 
91 static int nouveau_nv40_backlight_init(struct drm_device *dev)
92 {
93 	struct backlight_properties props;
94 	struct drm_nouveau_private *dev_priv = dev->dev_private;
95 	struct backlight_device *bd;
96 
97 	if (!(nv_rd32(dev, NV40_PMC_BACKLIGHT) & NV40_PMC_BACKLIGHT_MASK))
98 		return 0;
99 
100 	memset(&props, 0, sizeof(struct backlight_properties));
101 	props.max_brightness = 31;
102 	bd = backlight_device_register("nv_backlight", &dev->pdev->dev, dev,
103 				       &nv40_bl_ops, &props);
104 	if (IS_ERR(bd))
105 		return PTR_ERR(bd);
106 
107 	dev_priv->backlight = bd;
108 	bd->props.brightness = nv40_get_intensity(bd);
109 	backlight_update_status(bd);
110 
111 	return 0;
112 }
113 
114 static int nouveau_nv50_backlight_init(struct drm_device *dev)
115 {
116 	struct backlight_properties props;
117 	struct drm_nouveau_private *dev_priv = dev->dev_private;
118 	struct backlight_device *bd;
119 
120 	if (!nv_rd32(dev, NV50_PDISPLAY_SOR_BACKLIGHT))
121 		return 0;
122 
123 	memset(&props, 0, sizeof(struct backlight_properties));
124 	props.max_brightness = 1025;
125 	bd = backlight_device_register("nv_backlight", &dev->pdev->dev, dev,
126 				       &nv50_bl_ops, &props);
127 	if (IS_ERR(bd))
128 		return PTR_ERR(bd);
129 
130 	dev_priv->backlight = bd;
131 	bd->props.brightness = nv50_get_intensity(bd);
132 	backlight_update_status(bd);
133 	return 0;
134 }
135 
136 int nouveau_backlight_init(struct drm_device *dev)
137 {
138 	struct drm_nouveau_private *dev_priv = dev->dev_private;
139 
140 #ifdef CONFIG_ACPI
141 	if (acpi_video_backlight_support()) {
142 		NV_INFO(dev, "ACPI backlight interface available, "
143 			     "not registering our own\n");
144 		return 0;
145 	}
146 #endif
147 
148 	switch (dev_priv->card_type) {
149 	case NV_40:
150 		return nouveau_nv40_backlight_init(dev);
151 	case NV_50:
152 		return nouveau_nv50_backlight_init(dev);
153 	default:
154 		break;
155 	}
156 
157 	return 0;
158 }
159 
160 void nouveau_backlight_exit(struct drm_device *dev)
161 {
162 	struct drm_nouveau_private *dev_priv = dev->dev_private;
163 
164 	if (dev_priv->backlight) {
165 		backlight_device_unregister(dev_priv->backlight);
166 		dev_priv->backlight = NULL;
167 	}
168 }
169