linux-zen-server/drivers/gpu/drm/nouveau/nvkm/subdev/volt/gpio.c

99 lines
2.8 KiB
C

/*
* Copyright 2013 Red Hat Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Authors: Ben Skeggs
*/
#include <subdev/volt.h>
#include <subdev/bios.h>
#include <subdev/bios/gpio.h>
#include <subdev/gpio.h>
#include "priv.h"
static const u8 tags[] = {
DCB_GPIO_VID0, DCB_GPIO_VID1, DCB_GPIO_VID2, DCB_GPIO_VID3,
DCB_GPIO_VID4, DCB_GPIO_VID5, DCB_GPIO_VID6, DCB_GPIO_VID7,
};
int
nvkm_voltgpio_get(struct nvkm_volt *volt)
{
struct nvkm_gpio *gpio = volt->subdev.device->gpio;
u8 vid = 0;
int i;
for (i = 0; i < ARRAY_SIZE(tags); i++) {
if (volt->vid_mask & (1 << i)) {
int ret = nvkm_gpio_get(gpio, 0, tags[i], 0xff);
if (ret < 0)
return ret;
vid |= ret << i;
}
}
return vid;
}
int
nvkm_voltgpio_set(struct nvkm_volt *volt, u8 vid)
{
struct nvkm_gpio *gpio = volt->subdev.device->gpio;
int i;
for (i = 0; i < ARRAY_SIZE(tags); i++, vid >>= 1) {
if (volt->vid_mask & (1 << i)) {
int ret = nvkm_gpio_set(gpio, 0, tags[i], 0xff, vid & 1);
if (ret < 0)
return ret;
}
}
return 0;
}
int
nvkm_voltgpio_init(struct nvkm_volt *volt)
{
struct nvkm_subdev *subdev = &volt->subdev;
struct nvkm_gpio *gpio = subdev->device->gpio;
struct dcb_gpio_func func;
int i;
/* check we have gpio function info for each vid bit. on some
* boards (ie. nvs295) the vid mask has more bits than there
* are valid gpio functions... from traces, nvidia appear to
* just touch the existing ones, so let's mask off the invalid
* bits and continue with life
*/
for (i = 0; i < ARRAY_SIZE(tags); i++) {
if (volt->vid_mask & (1 << i)) {
int ret = nvkm_gpio_find(gpio, 0, tags[i], 0xff, &func);
if (ret) {
if (ret != -ENOENT)
return ret;
nvkm_debug(subdev, "VID bit %d has no GPIO\n", i);
volt->vid_mask &= ~(1 << i);
}
}
}
return 0;
}