common/eeprom/eeprom_layout.c

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