[go: nahoru, domu]
1/*
2 * Copyright 2013 Red Hat Inc.
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: Ben Skeggs
23 */
24
25#include <subdev/volt.h>
26#include <subdev/gpio.h>
27#include <subdev/bios/gpio.h>
28
29static const u8 tags[] = {
30	DCB_GPIO_VID0, DCB_GPIO_VID1, DCB_GPIO_VID2, DCB_GPIO_VID3,
31	DCB_GPIO_VID4, DCB_GPIO_VID5, DCB_GPIO_VID6, DCB_GPIO_VID7,
32};
33
34int
35nouveau_voltgpio_get(struct nouveau_volt *volt)
36{
37	struct nouveau_gpio *gpio = nouveau_gpio(volt);
38	u8 vid = 0;
39	int i;
40
41	for (i = 0; i < ARRAY_SIZE(tags); i++) {
42		if (volt->vid_mask & (1 << i)) {
43			int ret = gpio->get(gpio, 0, tags[i], 0xff);
44			if (ret < 0)
45				return ret;
46			vid |= ret << i;
47		}
48	}
49
50	return vid;
51}
52
53int
54nouveau_voltgpio_set(struct nouveau_volt *volt, u8 vid)
55{
56	struct nouveau_gpio *gpio = nouveau_gpio(volt);
57	int i;
58
59	for (i = 0; i < ARRAY_SIZE(tags); i++, vid >>= 1) {
60		if (volt->vid_mask & (1 << i)) {
61			int ret = gpio->set(gpio, 0, tags[i], 0xff, vid & 1);
62			if (ret < 0)
63				return ret;
64		}
65	}
66
67	return 0;
68}
69
70int
71nouveau_voltgpio_init(struct nouveau_volt *volt)
72{
73	struct nouveau_gpio *gpio = nouveau_gpio(volt);
74	struct dcb_gpio_func func;
75	int i;
76
77	/* check we have gpio function info for each vid bit.  on some
78	 * boards (ie. nvs295) the vid mask has more bits than there
79	 * are valid gpio functions... from traces, nvidia appear to
80	 * just touch the existing ones, so let's mask off the invalid
81	 * bits and continue with life
82	 */
83	for (i = 0; i < ARRAY_SIZE(tags); i++) {
84		if (volt->vid_mask & (1 << i)) {
85			int ret = gpio->find(gpio, 0, tags[i], 0xff, &func);
86			if (ret) {
87				if (ret != -ENOENT)
88					return ret;
89				nv_debug(volt, "VID bit %d has no GPIO\n", i);
90				volt->vid_mask &= ~(1 << i);
91			}
92		}
93	}
94
95	return 0;
96}
97