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1/*2 * Copyright 2013 Red Hat Inc.3 *4 * Permission is hereby granted, free of charge, to any person obtaining a5 * copy of this software and associated documentation files (the "Software"),6 * to deal in the Software without restriction, including without limitation7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,8 * and/or sell copies of the Software, and to permit persons to whom the9 * Software is furnished to do so, subject to the following conditions:10 *11 * The above copyright notice and this permission notice shall be included in12 * all copies or substantial portions of the Software.13 *14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR18 * 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 OR20 * OTHER DEALINGS IN THE SOFTWARE.21 *22 * Authors: Ben Skeggs23 */24#include <subdev/volt.h>25#include <subdev/bios.h>26#include <subdev/bios/gpio.h>27#include <subdev/gpio.h>28#include "priv.h"29 30static const u8 tags[] = {31 DCB_GPIO_VID0, DCB_GPIO_VID1, DCB_GPIO_VID2, DCB_GPIO_VID3,32 DCB_GPIO_VID4, DCB_GPIO_VID5, DCB_GPIO_VID6, DCB_GPIO_VID7,33};34 35int36nvkm_voltgpio_get(struct nvkm_volt *volt)37{38 struct nvkm_gpio *gpio = volt->subdev.device->gpio;39 u8 vid = 0;40 int i;41 42 for (i = 0; i < ARRAY_SIZE(tags); i++) {43 if (volt->vid_mask & (1 << i)) {44 int ret = nvkm_gpio_get(gpio, 0, tags[i], 0xff);45 if (ret < 0)46 return ret;47 vid |= ret << i;48 }49 }50 51 return vid;52}53 54int55nvkm_voltgpio_set(struct nvkm_volt *volt, u8 vid)56{57 struct nvkm_gpio *gpio = volt->subdev.device->gpio;58 int i;59 60 for (i = 0; i < ARRAY_SIZE(tags); i++, vid >>= 1) {61 if (volt->vid_mask & (1 << i)) {62 int ret = nvkm_gpio_set(gpio, 0, tags[i], 0xff, vid & 1);63 if (ret < 0)64 return ret;65 }66 }67 68 return 0;69}70 71int72nvkm_voltgpio_init(struct nvkm_volt *volt)73{74 struct nvkm_subdev *subdev = &volt->subdev;75 struct nvkm_gpio *gpio = subdev->device->gpio;76 struct dcb_gpio_func func;77 int i;78 79 /* check we have gpio function info for each vid bit. on some80 * boards (ie. nvs295) the vid mask has more bits than there81 * are valid gpio functions... from traces, nvidia appear to82 * just touch the existing ones, so let's mask off the invalid83 * bits and continue with life84 */85 for (i = 0; i < ARRAY_SIZE(tags); i++) {86 if (volt->vid_mask & (1 << i)) {87 int ret = nvkm_gpio_find(gpio, 0, tags[i], 0xff, &func);88 if (ret) {89 if (ret != -ENOENT)90 return ret;91 nvkm_debug(subdev, "VID bit %d has no GPIO\n", i);92 volt->vid_mask &= ~(1 << i);93 }94 }95 }96 97 return 0;98}99