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 41static enum led_brightness 42nouveau_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 58static void 59nouveau_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 82int 83nouveau_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 117void 118nouveau_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 126void 127nouveau_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 135void 136nouveau_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