xref: /netbsd-src/sys/dev/acpi/acpi_i2c.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /* $NetBSD: acpi_i2c.c,v 1.8 2020/08/24 05:37:41 msaitoh Exp $ */
2 
3 /*-
4  * Copyright (c) 2017 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Manuel Bouyer.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: acpi_i2c.c,v 1.8 2020/08/24 05:37:41 msaitoh Exp $");
34 
35 #include <dev/acpi/acpireg.h>
36 #include <dev/acpi/acpivar.h>
37 #include <dev/acpi/acpi_i2c.h>
38 
39 #define _COMPONENT	ACPI_BUS_COMPONENT
40 ACPI_MODULE_NAME	("acpi_i2c")
41 
42 static void
43 acpi_enter_i2c_hid(struct acpi_devnode *devnode, prop_dictionary_t dev)
44 {
45 	ACPI_OBJECT_LIST arg;
46 	ACPI_OBJECT obj[4];
47 	ACPI_OBJECT *osc;
48 	ACPI_BUFFER buf;
49 	ACPI_STATUS rv;
50 	/* 3cdff6f7-4267-4555-ad05-b30a3d8938de */
51 	static uint8_t i2c_hid_guid[] = {
52 		0xF7, 0xF6, 0xDF, 0x3C, 0x67, 0x42, 0x55, 0x45,
53 		0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE,
54 	};
55 
56 	arg.Count = 4;
57 	arg.Pointer = obj;
58 
59 	obj[0].Type = ACPI_TYPE_BUFFER;
60 	obj[0].Buffer.Length = sizeof(i2c_hid_guid);
61 	obj[0].Buffer.Pointer = i2c_hid_guid;
62 
63 	/* rev */
64 	obj[1].Type = ACPI_TYPE_INTEGER;
65 	obj[1].Integer.Value = 1;
66 
67 	/* func */
68 	obj[2].Type = ACPI_TYPE_INTEGER;
69 	obj[2].Integer.Value = 1;
70 
71 	obj[3].Type = ACPI_TYPE_PACKAGE;
72 	obj[3].Buffer.Length = 0;
73 
74 	buf.Pointer = NULL;
75 	buf.Length = ACPI_ALLOCATE_LOCAL_BUFFER;
76 
77 	rv = AcpiEvaluateObject(devnode->ad_handle, "_DSM", &arg, &buf);
78 
79 	if (ACPI_FAILURE(rv)) {
80 		aprint_error("failed to evaluate _DSM for %s: %s\n",
81 		    devnode->ad_name, AcpiFormatException(rv));
82 		return;
83 	}
84 
85 	osc = buf.Pointer;
86 	if (osc->Type != ACPI_TYPE_INTEGER) {
87 		aprint_error("bad _DSM return type %d for %s\n",
88 		    osc->Type, devnode->ad_name);
89 		return;
90 	}
91 	prop_dictionary_set_uint32(dev, "hid-descr-addr", osc->Integer.Value);
92 }
93 
94 struct acpi_i2c_id {
95 	const char *id;
96 	const char *compat;
97 	const int compatlen;
98 	void (*parse)(struct acpi_devnode *, prop_dictionary_t);
99 };
100 
101 static const struct acpi_i2c_id acpi_i2c_ids[] = {
102 	{
103 		.id = "PNP0C50",
104 		.compat = "hid-over-i2c",
105 		.compatlen = 13,
106 		.parse = acpi_enter_i2c_hid
107 	},
108 	{
109 		.id = "ACPI0C50",
110 		.compat = "hid-over-i2c",
111 		.compatlen = 13,
112 		.parse = acpi_enter_i2c_hid
113 	},
114 	{
115 		.id = NULL,
116 		.compat = NULL,
117 		.compatlen = 0,
118 		.parse = NULL
119 	}
120 };
121 
122 static const struct acpi_i2c_id *
123 acpi_i2c_search(const char *name)
124 {
125 	int i;
126 	for (i = 0; acpi_i2c_ids[i].id != NULL; i++) {
127 		if (strcmp(name, acpi_i2c_ids[i].id) == 0)
128 			return &acpi_i2c_ids[i];
129 	}
130 	return NULL;
131 }
132 
133 struct acpi_i2c_context {
134 	uint16_t i2c_addr;
135 };
136 
137 static ACPI_STATUS
138 acpi_i2c_resource_parse_callback(ACPI_RESOURCE *res, void *context)
139 {
140 	struct acpi_i2c_context *i2cc = context;
141 
142 	switch (res->Type) {
143 	case ACPI_RESOURCE_TYPE_END_TAG:
144 		break;
145 	case ACPI_RESOURCE_TYPE_SERIAL_BUS:
146 		switch (res->Data.I2cSerialBus.Type) {
147 		case ACPI_RESOURCE_SERIAL_TYPE_I2C:
148 			i2cc->i2c_addr = res->Data.I2cSerialBus.SlaveAddress;
149 			break;
150 		}
151 		break;
152 	case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
153 		break;
154 	default:
155 		printf("resource type 0x%x ignored\n", res->Type);
156 	}
157 	return_ACPI_STATUS(AE_OK);
158 }
159 
160 static void
161 acpi_enter_i2c_device(struct acpi_devnode *ad, prop_array_t array)
162 {
163 	prop_dictionary_t dev;
164 	struct acpi_i2c_context i2cc;
165 	ACPI_STATUS rv;
166 	int cidi;
167 	ACPI_PNP_DEVICE_ID_LIST *idlist;
168 	const char *name;
169 	static const struct acpi_i2c_id *i2c_id;
170 
171 	memset(&i2cc, 0, sizeof(i2cc));
172 	rv = AcpiWalkResources(ad->ad_handle, "_CRS",
173 	     acpi_i2c_resource_parse_callback, &i2cc);
174 	if (ACPI_FAILURE(rv)) {
175 		aprint_error("ACPI: unable to get resources "
176 		   "for %s: %s\n", ad->ad_name,
177 		   AcpiFormatException(rv));
178 		return;
179 	}
180 	if (i2cc.i2c_addr == 0)
181 		return;
182 	dev = prop_dictionary_create();
183 	if (dev == NULL) {
184 		aprint_error("ignoring device %s (no memory)\n",
185 		    ad->ad_name);
186 		return;
187 	}
188 	if ((ad->ad_devinfo->Valid &  ACPI_VALID_HID) == 0)
189 		name = ad->ad_name;
190 	else
191 		name = ad->ad_devinfo->HardwareId.String;
192 	prop_dictionary_set_string(dev, "name", name);
193 	prop_dictionary_set_uint32(dev, "addr", i2cc.i2c_addr);
194 	prop_dictionary_set_uint64(dev, "cookie", (uintptr_t)ad->ad_handle);
195 	/* first search by name, then by CID */
196 	i2c_id = acpi_i2c_search(name);
197 	idlist = &ad->ad_devinfo->CompatibleIdList;
198 	for (cidi = 0;
199 	    cidi < idlist->Count && i2c_id == NULL;
200 	    cidi++) {
201 		i2c_id = acpi_i2c_search(idlist->Ids[cidi].String);
202 	}
203 	if (i2c_id != NULL) {
204 		if (i2c_id->compat != NULL) {
205 			prop_data_t data;
206 			data = prop_data_create_copy(i2c_id->compat,
207 			    i2c_id->compatlen);
208 			prop_dictionary_set(dev, "compatible", data);
209 			prop_object_release(data);
210 		}
211 		if (i2c_id->parse != NULL)
212 			i2c_id->parse(ad, dev);
213 	}
214 	prop_array_add(array, dev);
215 	prop_object_release(dev);
216 }
217 
218 
219 prop_array_t
220 acpi_enter_i2c_devs(struct acpi_devnode *devnode)
221 {
222 	struct acpi_devnode *ad;
223 	prop_array_t array = prop_array_create();
224 
225 	if (array == NULL)
226 		return NULL;
227 
228 	SIMPLEQ_FOREACH(ad, &devnode->ad_child_head, ad_child_list) {
229 		if (ad->ad_devinfo->Type != ACPI_TYPE_DEVICE)
230 			continue;
231 		if (!acpi_device_present(ad->ad_handle))
232 			continue;
233 		acpi_enter_i2c_device(ad, array);
234 	}
235 	return array;
236 }
237