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}