LXR linux/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
  29struct 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
  38static void
  39nvkm_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 (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
  65static void
  66nvkm_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
  73static int
  74nvkm_fantog_get(struct nvkm_therm *therm)
  75{
  76        struct nvkm_fantog *fan = (void *)therm->fan;
  77        return fan->percent;
  78}
  79
  80static int
  81nvkm_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
  90int
  91nvkm_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}
 117