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/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/module.h>
34 #include <sys/errno.h>
35 #include <sys/bus.h>
36
37 #include <dev/pci/pcivar.h>
38 #include <dev/pci/pcireg.h>
39 #include <dev/iicbus/iicbus.h>
40 #include <dev/iicbus/iiconf.h>
41
42 /*
43 * Driver that attaches I2C devices.
44 */
45 static struct {
46 uint32_t pci_id;
47 const char *name;
48 uint8_t addr;
49 } slaves[] = {
50 { 0x9c628086, "isl", 0x88 },
51 { 0x9c618086, "cyapa", 0xce },
52 };
53
54 static void
chromebook_i2c_identify(driver_t * driver,device_t bus)55 chromebook_i2c_identify(driver_t *driver, device_t bus)
56 {
57 device_t controller;
58 device_t child;
59 int i;
60
61 /*
62 * A stopgap approach to preserve the status quo.
63 * A more intelligent approach is required to correctly
64 * identify a machine model and hardware available on it.
65 * For instance, DMI could be used.
66 * See http://lxr.free-electrons.com/source/drivers/platform/chrome/chromeos_laptop.c
67 */
68 controller = device_get_parent(bus);
69 if (strcmp(device_get_name(controller), "ig4iic") != 0)
70 return;
71
72 for (i = 0; i < nitems(slaves); i++) {
73 if (device_find_child(bus, slaves[i].name, -1) != NULL)
74 continue;
75 if (slaves[i].pci_id != pci_get_devid(controller))
76 continue;
77 child = BUS_ADD_CHILD(bus, 0, slaves[i].name, -1);
78 if (child != NULL)
79 iicbus_set_addr(child, slaves[i].addr);
80 }
81 }
82
83 static device_method_t chromebook_i2c_methods[] = {
84 DEVMETHOD(device_identify, chromebook_i2c_identify),
85 { 0, 0 }
86 };
87
88 static driver_t chromebook_i2c_driver = {
89 "chromebook_i2c",
90 chromebook_i2c_methods,
91 0 /* no softc */
92 };
93
94 DRIVER_MODULE(chromebook_i2c, iicbus, chromebook_i2c_driver, 0, 0);
95 MODULE_VERSION(chromebook_i2c, 1);
96
97