drivers/mfd/si476x-prop.c

   1 /*
   2  * drivers/mfd/si476x-prop.c -- Subroutines to access
   3  * properties of si476x chips
   4  *
   5  * Copyright (C) 2012 Innovative Converged Devices(ICD)
   6  * Copyright (C) 2013 Andrey Smirnov
   7  *
   8  * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; version 2 of the License.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * General Public License for more details.
  18  */
  19 #include <linux/module.h>
  20
  21 #include <linux/mfd/si476x-core.h>
  22
  23 struct si476x_property_range {
  24         u16 low, high;
  25 };
  26
  27 static bool si476x_core_element_is_in_array(u16 element,
  28                                             const u16 array[],
  29                                             size_t size)
  30 {
  31         int i;
  32
  33         for (i = 0; i < size; i++)
  34                 if (element == array[i])
  35                         return true;
  36
  37         return false;
  38 }
  39
  40 static bool si476x_core_element_is_in_range(u16 element,
  41                                             const struct si476x_property_range range[],
  42                                             size_t size)
  43 {
  44         int i;
  45
  46         for (i = 0; i < size; i++)
  47                 if (element <= range[i].high && element >= range[i].low)
  48                         return true;
  49
  50         return false;
  51 }
  52
  53 static bool si476x_core_is_valid_property_a10(struct si476x_core *core,
  54                                               u16 property)
  55 {
  56         static const u16 valid_properties[] = {
  57                 0x0000,
  58                 0x0500, 0x0501,
  59                 0x0600,
  60                 0x0709, 0x070C, 0x070D, 0x70E, 0x710,
  61                 0x0718,
  62                 0x1207, 0x1208,
  63                 0x2007,
  64                 0x2300,
  65         };
  66
  67         static const struct si476x_property_range valid_ranges[] = {
  68                 { 0x0200, 0x0203 },
  69                 { 0x0300, 0x0303 },
  70                 { 0x0400, 0x0404 },
  71                 { 0x0700, 0x0707 },
  72                 { 0x1100, 0x1102 },
  73                 { 0x1200, 0x1204 },
  74                 { 0x1300, 0x1306 },
  75                 { 0x2000, 0x2005 },
  76                 { 0x2100, 0x2104 },
  77                 { 0x2106, 0x2106 },
  78                 { 0x2200, 0x220E },
  79                 { 0x3100, 0x3104 },
  80                 { 0x3207, 0x320F },
  81                 { 0x3300, 0x3304 },
  82                 { 0x3500, 0x3517 },
  83                 { 0x3600, 0x3617 },
  84                 { 0x3700, 0x3717 },
  85                 { 0x4000, 0x4003 },
  86         };
  87
  88         return  si476x_core_element_is_in_range(property, valid_ranges,
  89                                                 ARRAY_SIZE(valid_ranges)) ||
  90                 si476x_core_element_is_in_array(property, valid_properties,
  91                                                 ARRAY_SIZE(valid_properties));
  92 }
  93
  94 static bool si476x_core_is_valid_property_a20(struct si476x_core *core,
  95                                               u16 property)
  96 {
  97         static const u16 valid_properties[] = {
  98                 0x071B,
  99                 0x1006,
 100                 0x2210,
 101                 0x3401,
 102         };
 103
 104         static const struct si476x_property_range valid_ranges[] = {
 105                 { 0x2215, 0x2219 },
 106         };
 107
 108         return  si476x_core_is_valid_property_a10(core, property) ||
 109                 si476x_core_element_is_in_range(property, valid_ranges,
 110                                                 ARRAY_SIZE(valid_ranges))  ||
 111                 si476x_core_element_is_in_array(property, valid_properties,
 112                                                 ARRAY_SIZE(valid_properties));
 113 }
 114
 115 static bool si476x_core_is_valid_property_a30(struct si476x_core *core,
 116                                               u16 property)
 117 {
 118         static const u16 valid_properties[] = {
 119                 0x071C, 0x071D,
 120                 0x1007, 0x1008,
 121                 0x220F, 0x2214,
 122                 0x2301,
 123                 0x3105, 0x3106,
 124                 0x3402,
 125         };
 126
 127         static const struct si476x_property_range valid_ranges[] = {
 128                 { 0x0405, 0x0411 },
 129                 { 0x2008, 0x200B },
 130                 { 0x2220, 0x2223 },
 131                 { 0x3100, 0x3106 },
 132         };
 133
 134         return  si476x_core_is_valid_property_a20(core, property) ||
 135                 si476x_core_element_is_in_range(property, valid_ranges,
 136                                                 ARRAY_SIZE(valid_ranges)) ||
 137                 si476x_core_element_is_in_array(property, valid_properties,
 138                                                 ARRAY_SIZE(valid_properties));
 139 }
 140
 141 typedef bool (*valid_property_pred_t) (struct si476x_core *, u16);
 142
 143 static bool si476x_core_is_valid_property(struct si476x_core *core,
 144                                           u16 property)
 145 {
 146         static const valid_property_pred_t is_valid_property[] = {
 147                 [SI476X_REVISION_A10] = si476x_core_is_valid_property_a10,
 148                 [SI476X_REVISION_A20] = si476x_core_is_valid_property_a20,
 149                 [SI476X_REVISION_A30] = si476x_core_is_valid_property_a30,
 150         };
 151
 152         BUG_ON(core->revision > SI476X_REVISION_A30 ||
 153                core->revision == -1);
 154         return is_valid_property[core->revision](core, property);
 155 }
 156
 157
 158 static bool si476x_core_is_readonly_property(struct si476x_core *core,
 159                                              u16 property)
 160 {
 161         BUG_ON(core->revision > SI476X_REVISION_A30 ||
 162                core->revision == -1);
 163
 164         switch (core->revision) {
 165         case SI476X_REVISION_A10:
 166                 return (property == 0x3200);
 167         case SI476X_REVISION_A20:
 168                 return (property == 0x1006 ||
 169                         property == 0x2210 ||
 170                         property == 0x3200);
 171         case SI476X_REVISION_A30:
 172                 return false;
 173         }
 174
 175         return false;
 176 }
 177
 178 static bool si476x_core_regmap_readable_register(struct device *dev,
 179                                                  unsigned int reg)
 180 {
 181         struct i2c_client *client = to_i2c_client(dev);
 182         struct si476x_core *core = i2c_get_clientdata(client);
 183
 184         return si476x_core_is_valid_property(core, (u16) reg);
 185
 186 }
 187
 188 static bool si476x_core_regmap_writable_register(struct device *dev,
 189                                                  unsigned int reg)
 190 {
 191         struct i2c_client *client = to_i2c_client(dev);
 192         struct si476x_core *core = i2c_get_clientdata(client);
 193
 194         return si476x_core_is_valid_property(core, (u16) reg) &&
 195                 !si476x_core_is_readonly_property(core, (u16) reg);
 196 }
 197
 198
 199 static int si476x_core_regmap_write(void *context, unsigned int reg,
 200                                     unsigned int val)
 201 {
 202         return si476x_core_cmd_set_property(context, reg, val);
 203 }
 204
 205 static int si476x_core_regmap_read(void *context, unsigned int reg,
 206                                    unsigned *val)
 207 {
 208         struct si476x_core *core = context;
 209         int err;
 210
 211         err = si476x_core_cmd_get_property(core, reg);
 212         if (err < 0)
 213                 return err;
 214
 215         *val = err;
 216
 217         return 0;
 218 }
 219
 220
 221 static const struct regmap_config si476x_regmap_config = {
 222         .reg_bits = 16,
 223         .val_bits = 16,
 224
 225         .max_register = 0x4003,
 226
 227         .writeable_reg = si476x_core_regmap_writable_register,
 228         .readable_reg = si476x_core_regmap_readable_register,
 229
 230         .reg_read = si476x_core_regmap_read,
 231         .reg_write = si476x_core_regmap_write,
 232
 233         .cache_type = REGCACHE_RBTREE,
 234 };
 235
 236 struct regmap *devm_regmap_init_si476x(struct si476x_core *core)
 237 {
 238         return devm_regmap_init(&core->client->dev, NULL,
 239                                 core, &si476x_regmap_config);
 240 }
 241 EXPORT_SYMBOL_GPL(devm_regmap_init_si476x);