1/*
2 * Copyright (C) 2016 Martin Peres
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 *  Martin Peres <martin.peres@free.fr>
29 */
30
31#include <linux/leds.h>
32
33#include "nouveau_led.h"
34#include <nvkm/subdev/gpio.h>
35
36static enum led_brightness
37nouveau_led_get_brightness(struct led_classdev *led)
38{
39	struct drm_device *drm_dev = container_of(led, struct nouveau_led, led)->dev;
40	struct nouveau_drm *drm = nouveau_drm(drm_dev);
41	struct nvif_object *device = &drm->client.device.object;
42	u32 div, duty;
43
44	div =  nvif_rd32(device, 0x61c880) & 0x00ffffff;
45	duty = nvif_rd32(device, 0x61c884) & 0x00ffffff;
46
47	if (div > 0)
48		return duty * LED_FULL / div;
49	else
50		return 0;
51}
52
53static void
54nouveau_led_set_brightness(struct led_classdev *led, enum led_brightness value)
55{
56	struct drm_device *drm_dev = container_of(led, struct nouveau_led, led)->dev;
57	struct nouveau_drm *drm = nouveau_drm(drm_dev);
58	struct nvif_object *device = &drm->client.device.object;
59
60	u32 input_clk = 27e6; /* PDISPLAY.SOR[1].PWM is connected to the crystal */
61	u32 freq = 100; /* this is what nvidia uses and it should be good-enough */
62	u32 div, duty;
63
64	div = input_clk / freq;
65	duty = value * div / LED_FULL;
66
67	/* for now, this is safe to directly poke those registers because:
68	 *  - A: nvidia never puts the logo led to any other PWM controler
69	 *       than PDISPLAY.SOR[1].PWM.
70	 *  - B: nouveau does not touch these registers anywhere else
71	 */
72	nvif_wr32(device, 0x61c880, div);
73	nvif_wr32(device, 0x61c884, 0xc0000000 | duty);
74}
75
76
77int
78nouveau_led_init(struct drm_device *dev)
79{
80	struct nouveau_drm *drm = nouveau_drm(dev);
81	struct nvkm_gpio *gpio = nvxx_gpio(&drm->client.device);
82	struct dcb_gpio_func logo_led;
83	int ret;
84
85	if (!gpio)
86		return 0;
87
88	/* check that there is a GPIO controlling the logo LED */
89	if (nvkm_gpio_find(gpio, 0, DCB_GPIO_LOGO_LED_PWM, 0xff, &logo_led))
90		return 0;
91
92	drm->led = kzalloc(sizeof(*drm->led), GFP_KERNEL);
93	if (!drm->led)
94		return -ENOMEM;
95	drm->led->dev = dev;
96
97	drm->led->led.name = "nvidia-logo";
98	drm->led->led.max_brightness = 255;
99	drm->led->led.brightness_get = nouveau_led_get_brightness;
100	drm->led->led.brightness_set = nouveau_led_set_brightness;
101
102	ret = led_classdev_register(dev->dev, &drm->led->led);
103	if (ret) {
104		kfree(drm->led);
105		drm->led = NULL;
106		return ret;
107	}
108
109	return 0;
110}
111
112void
113nouveau_led_suspend(struct drm_device *dev)
114{
115	struct nouveau_drm *drm = nouveau_drm(dev);
116
117	if (drm->led)
118		led_classdev_suspend(&drm->led->led);
119}
120
121void
122nouveau_led_resume(struct drm_device *dev)
123{
124	struct nouveau_drm *drm = nouveau_drm(dev);
125
126	if (drm->led)
127		led_classdev_resume(&drm->led->led);
128}
129
130void
131nouveau_led_fini(struct drm_device *dev)
132{
133	struct nouveau_drm *drm = nouveau_drm(dev);
134
135	if (drm->led) {
136		led_classdev_unregister(&drm->led->led);
137		kfree(drm->led);
138		drm->led = NULL;
139	}
140}
141