1/*-
2 * Copyright (c) 2016 The FreeBSD Project.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in
13 *    the documentation and/or other materials provided with the
14 *    distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
19 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
20 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
22 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
24 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD: stable/11/sys/dev/chromebook_platform/chromebook_platform.c 314551 2017-03-02 10:43:42Z avg $");
32
33#include <sys/param.h>
34#include <sys/systm.h>
35#include <sys/kernel.h>
36#include <sys/module.h>
37#include <sys/errno.h>
38#include <sys/bus.h>
39
40#include <dev/pci/pcivar.h>
41#include <dev/pci/pcireg.h>
42#include <dev/iicbus/iicbus.h>
43#include <dev/iicbus/iiconf.h>
44
45/*
46 * Driver that attaches I2C devices.
47 */
48static struct {
49	uint32_t	pci_id;
50	const char	*name;
51	uint8_t		addr;
52} slaves[] = {
53	{ 0x9c628086,	"isl",		0x88 },
54	{ 0x9c618086,	"cyapa",	0xce },
55};
56
57static void
58chromebook_i2c_identify(driver_t *driver, device_t bus)
59{
60	device_t controller;
61	device_t child;
62	int i;
63
64	/*
65	 * A stopgap approach to preserve the status quo.
66	 * A more intelligent approach is required to correctly
67	 * identify a machine model and hardware available on it.
68	 * For instance, DMI could be used.
69	 * See http://lxr.free-electrons.com/source/drivers/platform/chrome/chromeos_laptop.c
70	 */
71	controller = device_get_parent(bus);
72	if (strcmp(device_get_name(controller), "ig4iic_pci") != 0)
73		return;
74
75	for (i = 0; i < nitems(slaves); i++) {
76		if (device_find_child(bus, slaves[i].name, -1) != NULL)
77			continue;
78		if (slaves[i].pci_id != pci_get_devid(controller))
79			continue;
80		child = BUS_ADD_CHILD(bus, 0, slaves[i].name, -1);
81		if (child != NULL)
82			iicbus_set_addr(child, slaves[i].addr);
83	}
84}
85
86static device_method_t chromebook_i2c_methods[] = {
87	DEVMETHOD(device_identify,	chromebook_i2c_identify),
88	{ 0, 0 }
89};
90
91static driver_t chromebook_i2c_driver = {
92	"chromebook_i2c",
93	chromebook_i2c_methods,
94	0	/* no softc */
95};
96
97static devclass_t chromebook_i2c_devclass;
98
99DRIVER_MODULE(chromebook_i2c, iicbus, chromebook_i2c_driver,
100    chromebook_i2c_devclass, 0, 0);
101MODULE_VERSION(chromebook_i2c, 1);
102
103