kernel/drivers/gpu/drm/nouveau/nvkm/subdev/therm/fantog.c

   1 /*
   2  * Copyright 2012 The Nouveau community
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  20  * OTHER DEALINGS IN THE SOFTWARE.
  21  *
  22  * Authors: Martin Peres
  23  */
  24 #include "priv.h"
  25
  26 #include <subdev/gpio.h>
  27 #include <subdev/timer.h>
  28
  29 struct nvkm_fantog {
  30         struct nvkm_fan base;
  31         struct nvkm_alarm alarm;
  32         spinlock_t lock;
  33         u32 period_us;
  34         u32 percent;
  35         struct dcb_gpio_func func;
  36 };
  37
  38 static void
  39 nvkm_fantog_update(struct nvkm_fantog *fan, int percent)
  40 {
  41         struct nvkm_therm *therm = fan->base.parent;
  42         struct nvkm_device *device = therm->subdev.device;
  43         struct nvkm_timer *tmr = device->timer;
  44         struct nvkm_gpio *gpio = device->gpio;
  45         unsigned long flags;
  46         int duty;
  47
  48         spin_lock_irqsave(&fan->lock, flags);
  49         if (percent < 0)
  50                 percent = fan->percent;
  51         fan->percent = percent;
  52
  53         duty = !nvkm_gpio_get(gpio, 0, DCB_GPIO_FAN, 0xff);
  54         nvkm_gpio_set(gpio, 0, DCB_GPIO_FAN, 0xff, duty);
  55
  56         if (list_empty(&fan->alarm.head) && percent != (duty * 100)) {
  57                 u64 next_change = (percent * fan->period_us) / 100;
  58                 if (!duty)
  59                         next_change = fan->period_us - next_change;
  60                 nvkm_timer_alarm(tmr, next_change * 1000, &fan->alarm);
  61         }
  62         spin_unlock_irqrestore(&fan->lock, flags);
  63 }
  64
  65 static void
  66 nvkm_fantog_alarm(struct nvkm_alarm *alarm)
  67 {
  68         struct nvkm_fantog *fan =
  69                container_of(alarm, struct nvkm_fantog, alarm);
  70         nvkm_fantog_update(fan, -1);
  71 }
  72
  73 static int
  74 nvkm_fantog_get(struct nvkm_therm *therm)
  75 {
  76         struct nvkm_fantog *fan = (void *)therm->fan;
  77         return fan->percent;
  78 }
  79
  80 static int
  81 nvkm_fantog_set(struct nvkm_therm *therm, int percent)
  82 {
  83         struct nvkm_fantog *fan = (void *)therm->fan;
  84         if (therm->func->pwm_ctrl)
  85                 therm->func->pwm_ctrl(therm, fan->func.line, false);
  86         nvkm_fantog_update(fan, percent);
  87         return 0;
  88 }
  89
  90 int
  91 nvkm_fantog_create(struct nvkm_therm *therm, struct dcb_gpio_func *func)
  92 {
  93         struct nvkm_fantog *fan;
  94         int ret;
  95
  96         if (therm->func->pwm_ctrl) {
  97                 ret = therm->func->pwm_ctrl(therm, func->line, false);
  98                 if (ret)
  99                         return ret;
 100         }
 101
 102         fan = kzalloc(sizeof(*fan), GFP_KERNEL);
 103         therm->fan = &fan->base;
 104         if (!fan)
 105                 return -ENOMEM;
 106
 107         fan->base.type = "toggle";
 108         fan->base.get = nvkm_fantog_get;
 109         fan->base.set = nvkm_fantog_set;
 110         nvkm_alarm_init(&fan->alarm, nvkm_fantog_alarm);
 111         fan->period_us = 100000; /* 10Hz */
 112         fan->percent = 100;
 113         fan->func = *func;
 114         spin_lock_init(&fan->lock);
 115         return 0;
 116 }