1/* $NetBSD: nouveau_subdev_volt_gpio.c,v 1.1.1.1 2014/08/06 12:36:32 riastradh Exp $ */
2
3/*
4 * Copyright 2013 Red Hat Inc.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
23 *
24 * Authors: Ben Skeggs
25 */
26
27#include <sys/cdefs.h>
28__KERNEL_RCSID(0, "$NetBSD: nouveau_subdev_volt_gpio.c,v 1.1.1.1 2014/08/06 12:36:32 riastradh Exp $");
29
30#include <subdev/volt.h>
31#include <subdev/gpio.h>
32#include <subdev/bios/gpio.h>
33
34static const u8 tags[] = {
35 DCB_GPIO_VID0, DCB_GPIO_VID1, DCB_GPIO_VID2, DCB_GPIO_VID3,
36 DCB_GPIO_VID4, DCB_GPIO_VID5, DCB_GPIO_VID6, DCB_GPIO_VID7,
37};
38
39int
40nouveau_voltgpio_get(struct nouveau_volt *volt)
41{
42 struct nouveau_gpio *gpio = nouveau_gpio(volt);
43 u8 vid = 0;
44 int i;
45
46 for (i = 0; i < ARRAY_SIZE(tags); i++) {
47 if (volt->vid_mask & (1 << i)) {
48 int ret = gpio->get(gpio, 0, tags[i], 0xff);
49 if (ret < 0)
50 return ret;
51 vid |= ret << i;
52 }
53 }
54
55 return vid;
56}
57
58int
59nouveau_voltgpio_set(struct nouveau_volt *volt, u8 vid)
60{
61 struct nouveau_gpio *gpio = nouveau_gpio(volt);
62 int i;
63
64 for (i = 0; i < ARRAY_SIZE(tags); i++, vid >>= 1) {
65 if (volt->vid_mask & (1 << i)) {
66 int ret = gpio->set(gpio, 0, tags[i], 0xff, vid & 1);
67 if (ret < 0)
68 return ret;
69 }
70 }
71
72 return 0;
73}
74
75int
76nouveau_voltgpio_init(struct nouveau_volt *volt)
77{
78 struct nouveau_gpio *gpio = nouveau_gpio(volt);
79 struct dcb_gpio_func func;
80 int i;
81
82 /* check we have gpio function info for each vid bit. on some
83 * boards (ie. nvs295) the vid mask has more bits than there
84 * are valid gpio functions... from traces, nvidia appear to
85 * just touch the existing ones, so let's mask off the invalid
86 * bits and continue with life
87 */
88 for (i = 0; i < ARRAY_SIZE(tags); i++) {
89 if (volt->vid_mask & (1 << i)) {
90 int ret = gpio->find(gpio, 0, tags[i], 0xff, &func);
91 if (ret) {
92 if (ret != -ENOENT)
93 return ret;
94 nv_debug(volt, "VID bit %d has no GPIO\n", i);
95 volt->vid_mask &= ~(1 << i);
96 }
97 }
98 }
99
100 return 0;
101}
102