1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2009-2016 CompuLab, Ltd.
4  *
5  * Authors: Nikita Kiryanov <nikita@compulab.co.il>
6  *	    Igor Grinberg <grinberg@compulab.co.il>
7  */
8 
9 #include <common.h>
10 #include <linux/kernel.h>
11 #include <eeprom_layout.h>
12 #include <eeprom_field.h>
13 
14 #define NO_LAYOUT_FIELDS	"Unknown layout. Dumping raw data\n"
15 
16 struct eeprom_field layout_unknown[1] = {
17 	{ NO_LAYOUT_FIELDS, 256, NULL, eeprom_field_print_bin,
18 				       eeprom_field_update_bin },
19 };
20 
21 /*
22  * eeprom_layout_detect() - detect layout based on the contents of the data.
23  * @data: Pointer to the data to be analyzed.
24  *
25  * Returns: the detected layout version.
26  */
27 __weak int eeprom_layout_detect(unsigned char *data)
28 {
29 	return LAYOUT_VERSION_UNRECOGNIZED;
30 }
31 
32 /*
33  * __eeprom_layout_assign() - set the layout fields
34  * @layout:		A pointer to an existing struct layout.
35  * @layout_version:	The version number of the desired layout
36  */
37 __weak void __eeprom_layout_assign(struct eeprom_layout *layout,
38 				   int layout_version)
39 {
40 	layout->fields = layout_unknown;
41 	layout->num_of_fields = ARRAY_SIZE(layout_unknown);
42 }
43 void eeprom_layout_assign(struct eeprom_layout *layout, int layout_version) \
44 		__attribute__((weak, alias("__eeprom_layout_assign")));
45 
46 /*
47  * eeprom_layout_print() - print the layout and the data which is assigned to it
48  * @layout: A pointer to an existing struct layout.
49  */
50 static void eeprom_layout_print(const struct eeprom_layout *layout)
51 {
52 	int i;
53 	struct eeprom_field *fields = layout->fields;
54 
55 	for (i = 0; i < layout->num_of_fields; i++)
56 		fields[i].print(&fields[i]);
57 }
58 
59 /*
60  * eeprom_layout_update_field() - update a single field in the layout data.
61  * @layout:	A pointer to an existing struct layout.
62  * @field_name:	The name of the field to update.
63  * @new_data:	The new field data (a string. Format depends on the field)
64  *
65  * Returns: 0 on success, negative error value on failure.
66  */
67 static int eeprom_layout_update_field(struct eeprom_layout *layout,
68 				      char *field_name, char *new_data)
69 {
70 	int i, err;
71 	struct eeprom_field *fields = layout->fields;
72 
73 	if (new_data == NULL)
74 		return 0;
75 
76 	if (field_name == NULL)
77 		return -1;
78 
79 	for (i = 0; i < layout->num_of_fields; i++) {
80 		if (fields[i].name == RESERVED_FIELDS ||
81 		    strcmp(fields[i].name, field_name))
82 			continue;
83 
84 		err = fields[i].update(&fields[i], new_data);
85 		if (err)
86 			printf("Invalid data for field %s\n", field_name);
87 
88 		return err;
89 	}
90 
91 	printf("No such field '%s'\n", field_name);
92 
93 	return -1;
94 }
95 
96 /*
97  * eeprom_layout_setup() - setup layout struct with the layout data and
98  *			   metadata as dictated by layout_version
99  * @layout:	A pointer to an existing struct layout.
100  * @buf:	A buffer initialized with the eeprom data.
101  * @buf_size:	Size of buf in bytes.
102  * @layout version: The version number of the layout.
103  */
104 void eeprom_layout_setup(struct eeprom_layout *layout, unsigned char *buf,
105 			 unsigned int buf_size, int layout_version)
106 {
107 	int i;
108 
109 	if (layout_version == LAYOUT_VERSION_AUTODETECT)
110 		layout->layout_version = eeprom_layout_detect(buf);
111 	else
112 		layout->layout_version = layout_version;
113 
114 	eeprom_layout_assign(layout, layout_version);
115 	layout->data = buf;
116 	for (i = 0; i < layout->num_of_fields; i++) {
117 		layout->fields[i].buf = buf;
118 		buf += layout->fields[i].size;
119 	}
120 
121 	layout->data_size = buf_size;
122 	layout->print = eeprom_layout_print;
123 	layout->update = eeprom_layout_update_field;
124 }
125