1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2013 Intel Corporation. All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License version
7 * 2 as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 *
15 */
16 #include <linux/i2c.h>
17 #include <linux/firmware.h>
18 #include <linux/device.h>
19 #include <linux/export.h>
20 #include "../include/linux/libmsrlisthelper.h"
21 #include <linux/module.h>
22 #include <linux/slab.h>
23
24 /* Tagged binary data container structure definitions. */
25 struct tbd_header {
26 u32 tag; /*!< Tag identifier, also checks endianness */
27 u32 size; /*!< Container size including this header */
28 u32 version; /*!< Version, format 0xYYMMDDVV */
29 u32 revision; /*!< Revision, format 0xYYMMDDVV */
30 u32 config_bits; /*!< Configuration flag bits set */
31 u32 checksum; /*!< Global checksum, header included */
32 } __packed;
33
34 struct tbd_record_header {
35 u32 size; /*!< Size of record including header */
36 u8 format_id; /*!< tbd_format_t enumeration values used */
37 u8 packing_key; /*!< Packing method; 0 = no packing */
38 u16 class_id; /*!< tbd_class_t enumeration values used */
39 } __packed;
40
41 struct tbd_data_record_header {
42 u16 next_offset;
43 u16 flags;
44 u16 data_offset;
45 u16 data_size;
46 } __packed;
47
48 #define TBD_CLASS_DRV_ID 2
49
set_msr_configuration(struct i2c_client * client,uint8_t * bufptr,unsigned int size)50 static int set_msr_configuration(struct i2c_client *client, uint8_t *bufptr,
51 unsigned int size)
52 {
53 /*
54 * The configuration data contains any number of sequences where
55 * the first byte (that is, uint8_t) that marks the number of bytes
56 * in the sequence to follow, is indeed followed by the indicated
57 * number of bytes of actual data to be written to sensor.
58 * By convention, the first two bytes of actual data should be
59 * understood as an address in the sensor address space (hibyte
60 * followed by lobyte) where the remaining data in the sequence
61 * will be written.
62 */
63
64 u8 *ptr = bufptr;
65
66 while (ptr < bufptr + size) {
67 struct i2c_msg msg = {
68 .addr = client->addr,
69 .flags = 0,
70 };
71 int ret;
72
73 /* How many bytes */
74 msg.len = *ptr++;
75 /* Where the bytes are located */
76 msg.buf = ptr;
77 ptr += msg.len;
78
79 if (ptr > bufptr + size)
80 /* Accessing data beyond bounds is not tolerated */
81 return -EINVAL;
82
83 ret = i2c_transfer(client->adapter, &msg, 1);
84 if (ret < 0) {
85 dev_err(&client->dev, "i2c write error: %d", ret);
86 return ret;
87 }
88 }
89 return 0;
90 }
91
parse_and_apply(struct i2c_client * client,uint8_t * buffer,unsigned int size)92 static int parse_and_apply(struct i2c_client *client, uint8_t *buffer,
93 unsigned int size)
94 {
95 u8 *endptr8 = buffer + size;
96 struct tbd_data_record_header *header =
97 (struct tbd_data_record_header *)buffer;
98
99 /* There may be any number of datasets present */
100 unsigned int dataset = 0;
101
102 do {
103 /* In below, four variables are read from buffer */
104 if ((uint8_t *)header + sizeof(*header) > endptr8)
105 return -EINVAL;
106
107 /* All data should be located within given buffer */
108 if ((uint8_t *)header + header->data_offset +
109 header->data_size > endptr8)
110 return -EINVAL;
111
112 /* We have a new valid dataset */
113 dataset++;
114 /* See whether there is MSR data */
115 /* If yes, update the reg info */
116 if (header->data_size && (header->flags & 1)) {
117 int ret;
118
119 dev_info(&client->dev,
120 "New MSR data for sensor driver (dataset %02d) size:%d\n",
121 dataset, header->data_size);
122 ret = set_msr_configuration(client,
123 buffer + header->data_offset,
124 header->data_size);
125 if (ret)
126 return ret;
127 }
128 header = (struct tbd_data_record_header *)(buffer +
129 header->next_offset);
130 } while (header->next_offset);
131
132 return 0;
133 }
134
apply_msr_data(struct i2c_client * client,const struct firmware * fw)135 int apply_msr_data(struct i2c_client *client, const struct firmware *fw)
136 {
137 struct tbd_header *header;
138 struct tbd_record_header *record;
139
140 if (!fw) {
141 dev_warn(&client->dev, "Drv data is not loaded.\n");
142 return -EINVAL;
143 }
144
145 if (sizeof(*header) > fw->size)
146 return -EINVAL;
147
148 header = (struct tbd_header *)fw->data;
149 /* Check that we have drvb block. */
150 if (memcmp(&header->tag, "DRVB", 4))
151 return -EINVAL;
152
153 /* Check the size */
154 if (header->size != fw->size)
155 return -EINVAL;
156
157 if (sizeof(*header) + sizeof(*record) > fw->size)
158 return -EINVAL;
159
160 record = (struct tbd_record_header *)(header + 1);
161 /* Check that class id mathes tbd's drv id. */
162 if (record->class_id != TBD_CLASS_DRV_ID)
163 return -EINVAL;
164
165 /* Size 0 shall not be treated as an error */
166 if (!record->size)
167 return 0;
168
169 return parse_and_apply(client, (uint8_t *)(record + 1), record->size);
170 }
171 EXPORT_SYMBOL_GPL(apply_msr_data);
172
load_msr_list(struct i2c_client * client,char * name,const struct firmware ** fw)173 int load_msr_list(struct i2c_client *client, char *name,
174 const struct firmware **fw)
175 {
176 int ret = request_firmware(fw, name, &client->dev);
177
178 if (ret) {
179 dev_err(&client->dev,
180 "Error %d while requesting firmware %s\n",
181 ret, name);
182 return ret;
183 }
184 dev_info(&client->dev, "Received %lu bytes drv data\n",
185 (unsigned long)(*fw)->size);
186
187 return 0;
188 }
189 EXPORT_SYMBOL_GPL(load_msr_list);
190
release_msr_list(struct i2c_client * client,const struct firmware * fw)191 void release_msr_list(struct i2c_client *client, const struct firmware *fw)
192 {
193 release_firmware(fw);
194 }
195 EXPORT_SYMBOL_GPL(release_msr_list);
196
init_msrlisthelper(void)197 static int init_msrlisthelper(void)
198 {
199 return 0;
200 }
201
exit_msrlisthelper(void)202 static void exit_msrlisthelper(void)
203 {
204 }
205
206 module_init(init_msrlisthelper);
207 module_exit(exit_msrlisthelper);
208
209 MODULE_AUTHOR("Jukka Kaartinen <jukka.o.kaartinen@intel.com>");
210 MODULE_LICENSE("GPL");
211