1 /* $NetBSD: nouveau_led.c,v 1.2 2021/12/18 23:45:32 riastradh Exp $ */
2
3 /*
4 * Copyright (C) 2016 Martin Peres
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining
7 * a copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sublicense, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial
16 * portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
21 * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
22 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
23 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
24 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 */
27
28 /*
29 * Authors:
30 * Martin Peres <martin.peres@free.fr>
31 */
32
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: nouveau_led.c,v 1.2 2021/12/18 23:45:32 riastradh Exp $");
35
36 #include <linux/leds.h>
37
38 #include "nouveau_led.h"
39 #include <nvkm/subdev/gpio.h>
40
41 static enum led_brightness
nouveau_led_get_brightness(struct led_classdev * led)42 nouveau_led_get_brightness(struct led_classdev *led)
43 {
44 struct drm_device *drm_dev = container_of(led, struct nouveau_led, led)->dev;
45 struct nouveau_drm *drm = nouveau_drm(drm_dev);
46 struct nvif_object *device = &drm->client.device.object;
47 u32 div, duty;
48
49 div = nvif_rd32(device, 0x61c880) & 0x00ffffff;
50 duty = nvif_rd32(device, 0x61c884) & 0x00ffffff;
51
52 if (div > 0)
53 return duty * LED_FULL / div;
54 else
55 return 0;
56 }
57
58 static void
nouveau_led_set_brightness(struct led_classdev * led,enum led_brightness value)59 nouveau_led_set_brightness(struct led_classdev *led, enum led_brightness value)
60 {
61 struct drm_device *drm_dev = container_of(led, struct nouveau_led, led)->dev;
62 struct nouveau_drm *drm = nouveau_drm(drm_dev);
63 struct nvif_object *device = &drm->client.device.object;
64
65 u32 input_clk = 27e6; /* PDISPLAY.SOR[1].PWM is connected to the crystal */
66 u32 freq = 100; /* this is what nvidia uses and it should be good-enough */
67 u32 div, duty;
68
69 div = input_clk / freq;
70 duty = value * div / LED_FULL;
71
72 /* for now, this is safe to directly poke those registers because:
73 * - A: nvidia never puts the logo led to any other PWM controler
74 * than PDISPLAY.SOR[1].PWM.
75 * - B: nouveau does not touch these registers anywhere else
76 */
77 nvif_wr32(device, 0x61c880, div);
78 nvif_wr32(device, 0x61c884, 0xc0000000 | duty);
79 }
80
81
82 int
nouveau_led_init(struct drm_device * dev)83 nouveau_led_init(struct drm_device *dev)
84 {
85 struct nouveau_drm *drm = nouveau_drm(dev);
86 struct nvkm_gpio *gpio = nvxx_gpio(&drm->client.device);
87 struct dcb_gpio_func logo_led;
88 int ret;
89
90 if (!gpio)
91 return 0;
92
93 /* check that there is a GPIO controlling the logo LED */
94 if (nvkm_gpio_find(gpio, 0, DCB_GPIO_LOGO_LED_PWM, 0xff, &logo_led))
95 return 0;
96
97 drm->led = kzalloc(sizeof(*drm->led), GFP_KERNEL);
98 if (!drm->led)
99 return -ENOMEM;
100 drm->led->dev = dev;
101
102 drm->led->led.name = "nvidia-logo";
103 drm->led->led.max_brightness = 255;
104 drm->led->led.brightness_get = nouveau_led_get_brightness;
105 drm->led->led.brightness_set = nouveau_led_set_brightness;
106
107 ret = led_classdev_register(dev->dev, &drm->led->led);
108 if (ret) {
109 kfree(drm->led);
110 drm->led = NULL;
111 return ret;
112 }
113
114 return 0;
115 }
116
117 void
nouveau_led_suspend(struct drm_device * dev)118 nouveau_led_suspend(struct drm_device *dev)
119 {
120 struct nouveau_drm *drm = nouveau_drm(dev);
121
122 if (drm->led)
123 led_classdev_suspend(&drm->led->led);
124 }
125
126 void
nouveau_led_resume(struct drm_device * dev)127 nouveau_led_resume(struct drm_device *dev)
128 {
129 struct nouveau_drm *drm = nouveau_drm(dev);
130
131 if (drm->led)
132 led_classdev_resume(&drm->led->led);
133 }
134
135 void
nouveau_led_fini(struct drm_device * dev)136 nouveau_led_fini(struct drm_device *dev)
137 {
138 struct nouveau_drm *drm = nouveau_drm(dev);
139
140 if (drm->led) {
141 led_classdev_unregister(&drm->led->led);
142 kfree(drm->led);
143 drm->led = NULL;
144 }
145 }
146