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_priv {
  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_priv *priv, int percent)
  40 {
  41         struct nvkm_therm_priv *tpriv = (void *)priv->base.parent;
  42         struct nvkm_timer *ptimer = nvkm_timer(tpriv);
  43         struct nvkm_gpio *gpio = nvkm_gpio(tpriv);
  44         unsigned long flags;
  45         int duty;
  46
  47         spin_lock_irqsave(&priv->lock, flags);
  48         if (percent < 0)
  49                 percent = priv->percent;
  50         priv->percent = percent;
  51
  52         duty = !gpio->get(gpio, 0, DCB_GPIO_FAN, 0xff);
  53         gpio->set(gpio, 0, DCB_GPIO_FAN, 0xff, duty);
  54
  55         if (list_empty(&priv->alarm.head) && percent != (duty * 100)) {
  56                 u64 next_change = (percent * priv->period_us) / 100;
  57                 if (!duty)
  58                         next_change = priv->period_us - next_change;
  59                 ptimer->alarm(ptimer, next_change * 1000, &priv->alarm);
  60         }
  61         spin_unlock_irqrestore(&priv->lock, flags);
  62 }
  63
  64 static void
  65 nvkm_fantog_alarm(struct nvkm_alarm *alarm)
  66 {
  67         struct nvkm_fantog_priv *priv =
  68                container_of(alarm, struct nvkm_fantog_priv, alarm);
  69         nvkm_fantog_update(priv, -1);
  70 }
  71
  72 static int
  73 nvkm_fantog_get(struct nvkm_therm *therm)
  74 {
  75         struct nvkm_therm_priv *tpriv = (void *)therm;
  76         struct nvkm_fantog_priv *priv = (void *)tpriv->fan;
  77         return priv->percent;
  78 }
  79
  80 static int
  81 nvkm_fantog_set(struct nvkm_therm *therm, int percent)
  82 {
  83         struct nvkm_therm_priv *tpriv = (void *)therm;
  84         struct nvkm_fantog_priv *priv = (void *)tpriv->fan;
  85         if (therm->pwm_ctrl)
  86                 therm->pwm_ctrl(therm, priv->func.line, false);
  87         nvkm_fantog_update(priv, percent);
  88         return 0;
  89 }
  90
  91 int
  92 nvkm_fantog_create(struct nvkm_therm *therm, struct dcb_gpio_func *func)
  93 {
  94         struct nvkm_therm_priv *tpriv = (void *)therm;
  95         struct nvkm_fantog_priv *priv;
  96         int ret;
  97
  98         if (therm->pwm_ctrl) {
  99                 ret = therm->pwm_ctrl(therm, func->line, false);
 100                 if (ret)
 101                         return ret;
 102         }
 103
 104         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 105         tpriv->fan = &priv->base;
 106         if (!priv)
 107                 return -ENOMEM;
 108
 109         priv->base.type = "toggle";
 110         priv->base.get = nvkm_fantog_get;
 111         priv->base.set = nvkm_fantog_set;
 112         nvkm_alarm_init(&priv->alarm, nvkm_fantog_alarm);
 113         priv->period_us = 100000; /* 10Hz */
 114         priv->percent = 100;
 115         priv->func = *func;
 116         spin_lock_init(&priv->lock);
 117         return 0;
 118 }