xref: /linux/drivers/iio/imu/inv_mpu6050/inv_mpu_acpi.c (revision 0883c2c06fb5bcf5b9e008270827e63c09a88c1e)
1 /*
2  * inv_mpu_acpi: ACPI processing for creating client devices
3  * Copyright (c) 2015, Intel Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  */
14 
15 #ifdef CONFIG_ACPI
16 
17 #include <linux/kernel.h>
18 #include <linux/i2c.h>
19 #include <linux/dmi.h>
20 #include <linux/acpi.h>
21 #include "inv_mpu_iio.h"
22 
23 enum inv_mpu_product_name {
24 	INV_MPU_NOT_MATCHED,
25 	INV_MPU_ASUS_T100TA,
26 };
27 
28 static enum inv_mpu_product_name matched_product_name;
29 
30 static int __init asus_t100_matched(const struct dmi_system_id *d)
31 {
32 	matched_product_name = INV_MPU_ASUS_T100TA;
33 
34 	return 0;
35 }
36 
37 static const struct dmi_system_id inv_mpu_dev_list[] = {
38 	{
39 	.callback = asus_t100_matched,
40 	.ident = "Asus Transformer Book T100",
41 		.matches = {
42 			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC"),
43 			DMI_MATCH(DMI_PRODUCT_NAME, "T100TA"),
44 			DMI_MATCH(DMI_PRODUCT_VERSION, "1.0"),
45 		},
46 	},
47 	/* Add more matching tables here..*/
48 	{}
49 };
50 
51 static int asus_acpi_get_sensor_info(struct acpi_device *adev,
52 				     struct i2c_client *client,
53 				     struct i2c_board_info *info)
54 {
55 	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
56 	int i;
57 	acpi_status status;
58 	union acpi_object *cpm;
59 
60 	status = acpi_evaluate_object(adev->handle, "CNF0", NULL, &buffer);
61 	if (ACPI_FAILURE(status))
62 		return -ENODEV;
63 
64 	cpm = buffer.pointer;
65 	for (i = 0; i < cpm->package.count; ++i) {
66 		union acpi_object *elem;
67 		int j;
68 
69 		elem = &cpm->package.elements[i];
70 		for (j = 0; j < elem->package.count; ++j) {
71 			union acpi_object *sub_elem;
72 
73 			sub_elem = &elem->package.elements[j];
74 			if (sub_elem->type == ACPI_TYPE_STRING)
75 				strlcpy(info->type, sub_elem->string.pointer,
76 					sizeof(info->type));
77 			else if (sub_elem->type == ACPI_TYPE_INTEGER) {
78 				if (sub_elem->integer.value != client->addr) {
79 					info->addr = sub_elem->integer.value;
80 					break; /* Not a MPU6500 primary */
81 				}
82 			}
83 		}
84 	}
85 
86 	kfree(buffer.pointer);
87 
88 	return cpm->package.count;
89 }
90 
91 static int acpi_i2c_check_resource(struct acpi_resource *ares, void *data)
92 {
93 	u32 *addr = data;
94 
95 	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
96 		struct acpi_resource_i2c_serialbus *sb;
97 
98 		sb = &ares->data.i2c_serial_bus;
99 		if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
100 			if (*addr)
101 				*addr |= (sb->slave_address << 16);
102 			else
103 				*addr = sb->slave_address;
104 		}
105 	}
106 
107 	/* Tell the ACPI core that we already copied this address */
108 	return 1;
109 }
110 
111 static int inv_mpu_process_acpi_config(struct i2c_client *client,
112 				       unsigned short *primary_addr,
113 				       unsigned short *secondary_addr)
114 {
115 	const struct acpi_device_id *id;
116 	struct acpi_device *adev;
117 	u32 i2c_addr = 0;
118 	LIST_HEAD(resources);
119 	int ret;
120 
121 	id = acpi_match_device(client->dev.driver->acpi_match_table,
122 			       &client->dev);
123 	if (!id)
124 		return -ENODEV;
125 
126 	adev = ACPI_COMPANION(&client->dev);
127 	if (!adev)
128 		return -ENODEV;
129 
130 	ret = acpi_dev_get_resources(adev, &resources,
131 				     acpi_i2c_check_resource, &i2c_addr);
132 	if (ret < 0)
133 		return ret;
134 
135 	acpi_dev_free_resource_list(&resources);
136 	*primary_addr = i2c_addr & 0x0000ffff;
137 	*secondary_addr = (i2c_addr & 0xffff0000) >> 16;
138 
139 	return 0;
140 }
141 
142 int inv_mpu_acpi_create_mux_client(struct i2c_client *client)
143 {
144 	struct inv_mpu6050_state *st = iio_priv(dev_get_drvdata(&client->dev));
145 
146 	st->mux_client = NULL;
147 	if (ACPI_HANDLE(&client->dev)) {
148 		struct i2c_board_info info;
149 		struct acpi_device *adev;
150 		int ret = -1;
151 
152 		adev = ACPI_COMPANION(&client->dev);
153 		memset(&info, 0, sizeof(info));
154 
155 		dmi_check_system(inv_mpu_dev_list);
156 		switch (matched_product_name) {
157 		case INV_MPU_ASUS_T100TA:
158 			ret = asus_acpi_get_sensor_info(adev, client,
159 							&info);
160 			break;
161 		/* Add more matched product processing here */
162 		default:
163 			break;
164 		}
165 
166 		if (ret < 0) {
167 			/* No matching DMI, so create device on INV6XX type */
168 			unsigned short primary, secondary;
169 
170 			ret = inv_mpu_process_acpi_config(client, &primary,
171 							  &secondary);
172 			if (!ret && secondary) {
173 				char *name;
174 
175 				info.addr = secondary;
176 				strlcpy(info.type, dev_name(&adev->dev),
177 					sizeof(info.type));
178 				name = strchr(info.type, ':');
179 				if (name)
180 					*name = '\0';
181 				strlcat(info.type, "-client",
182 					sizeof(info.type));
183 			} else
184 				return 0; /* no secondary addr, which is OK */
185 		}
186 		st->mux_client = i2c_new_device(st->muxc->adapter[0], &info);
187 		if (!st->mux_client)
188 			return -ENODEV;
189 	}
190 
191 	return 0;
192 }
193 
194 void inv_mpu_acpi_delete_mux_client(struct i2c_client *client)
195 {
196 	struct inv_mpu6050_state *st = iio_priv(dev_get_drvdata(&client->dev));
197 
198 	if (st->mux_client)
199 		i2c_unregister_device(st->mux_client);
200 }
201 #else
202 
203 #include "inv_mpu_iio.h"
204 
205 int inv_mpu_acpi_create_mux_client(struct i2c_client *client)
206 {
207 	return 0;
208 }
209 
210 void inv_mpu_acpi_delete_mux_client(struct i2c_client *client)
211 {
212 }
213 #endif
214