1 /* 2 * Register map access API - SPMI support 3 * 4 * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved. 5 * 6 * Based on regmap-i2c.c: 7 * Copyright 2011 Wolfson Microelectronics plc 8 * Author: Mark Brown <broonie@opensource.wolfsonmicro.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 version 2 and 12 * only version 2 as published by the Free Software Foundation. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 * 19 */ 20 #include <linux/regmap.h> 21 #include <linux/spmi.h> 22 #include <linux/module.h> 23 #include <linux/init.h> 24 25 static int regmap_spmi_base_read(void *context, 26 const void *reg, size_t reg_size, 27 void *val, size_t val_size) 28 { 29 u8 addr = *(u8 *)reg; 30 int err = 0; 31 32 BUG_ON(reg_size != 1); 33 34 while (val_size-- && !err) 35 err = spmi_register_read(context, addr++, val++); 36 37 return err; 38 } 39 40 static int regmap_spmi_base_gather_write(void *context, 41 const void *reg, size_t reg_size, 42 const void *val, size_t val_size) 43 { 44 const u8 *data = val; 45 u8 addr = *(u8 *)reg; 46 int err = 0; 47 48 BUG_ON(reg_size != 1); 49 50 /* 51 * SPMI defines a more bandwidth-efficient 'Register 0 Write' sequence, 52 * use it when possible. 53 */ 54 if (addr == 0 && val_size) { 55 err = spmi_register_zero_write(context, *data); 56 if (err) 57 goto err_out; 58 59 data++; 60 addr++; 61 val_size--; 62 } 63 64 while (val_size) { 65 err = spmi_register_write(context, addr, *data); 66 if (err) 67 goto err_out; 68 69 data++; 70 addr++; 71 val_size--; 72 } 73 74 err_out: 75 return err; 76 } 77 78 static int regmap_spmi_base_write(void *context, const void *data, 79 size_t count) 80 { 81 BUG_ON(count < 1); 82 return regmap_spmi_base_gather_write(context, data, 1, data + 1, 83 count - 1); 84 } 85 86 static struct regmap_bus regmap_spmi_base = { 87 .read = regmap_spmi_base_read, 88 .write = regmap_spmi_base_write, 89 .gather_write = regmap_spmi_base_gather_write, 90 .reg_format_endian_default = REGMAP_ENDIAN_NATIVE, 91 .val_format_endian_default = REGMAP_ENDIAN_NATIVE, 92 }; 93 94 struct regmap *__regmap_init_spmi_base(struct spmi_device *sdev, 95 const struct regmap_config *config, 96 struct lock_class_key *lock_key, 97 const char *lock_name) 98 { 99 return __regmap_init(&sdev->dev, ®map_spmi_base, sdev, config, 100 lock_key, lock_name); 101 } 102 EXPORT_SYMBOL_GPL(__regmap_init_spmi_base); 103 104 struct regmap *__devm_regmap_init_spmi_base(struct spmi_device *sdev, 105 const struct regmap_config *config, 106 struct lock_class_key *lock_key, 107 const char *lock_name) 108 { 109 return __devm_regmap_init(&sdev->dev, ®map_spmi_base, sdev, config, 110 lock_key, lock_name); 111 } 112 EXPORT_SYMBOL_GPL(__devm_regmap_init_spmi_base); 113 114 static int regmap_spmi_ext_read(void *context, 115 const void *reg, size_t reg_size, 116 void *val, size_t val_size) 117 { 118 int err = 0; 119 size_t len; 120 u16 addr; 121 122 BUG_ON(reg_size != 2); 123 124 addr = *(u16 *)reg; 125 126 /* 127 * Split accesses into two to take advantage of the more 128 * bandwidth-efficient 'Extended Register Read' command when possible 129 */ 130 while (addr <= 0xFF && val_size) { 131 len = min_t(size_t, val_size, 16); 132 133 err = spmi_ext_register_read(context, addr, val, len); 134 if (err) 135 goto err_out; 136 137 addr += len; 138 val += len; 139 val_size -= len; 140 } 141 142 while (val_size) { 143 len = min_t(size_t, val_size, 8); 144 145 err = spmi_ext_register_readl(context, addr, val, val_size); 146 if (err) 147 goto err_out; 148 149 addr += len; 150 val += len; 151 val_size -= len; 152 } 153 154 err_out: 155 return err; 156 } 157 158 static int regmap_spmi_ext_gather_write(void *context, 159 const void *reg, size_t reg_size, 160 const void *val, size_t val_size) 161 { 162 int err = 0; 163 size_t len; 164 u16 addr; 165 166 BUG_ON(reg_size != 2); 167 168 addr = *(u16 *)reg; 169 170 while (addr <= 0xFF && val_size) { 171 len = min_t(size_t, val_size, 16); 172 173 err = spmi_ext_register_write(context, addr, val, len); 174 if (err) 175 goto err_out; 176 177 addr += len; 178 val += len; 179 val_size -= len; 180 } 181 182 while (val_size) { 183 len = min_t(size_t, val_size, 8); 184 185 err = spmi_ext_register_writel(context, addr, val, len); 186 if (err) 187 goto err_out; 188 189 addr += len; 190 val += len; 191 val_size -= len; 192 } 193 194 err_out: 195 return err; 196 } 197 198 static int regmap_spmi_ext_write(void *context, const void *data, 199 size_t count) 200 { 201 BUG_ON(count < 2); 202 return regmap_spmi_ext_gather_write(context, data, 2, data + 2, 203 count - 2); 204 } 205 206 static struct regmap_bus regmap_spmi_ext = { 207 .read = regmap_spmi_ext_read, 208 .write = regmap_spmi_ext_write, 209 .gather_write = regmap_spmi_ext_gather_write, 210 .reg_format_endian_default = REGMAP_ENDIAN_NATIVE, 211 .val_format_endian_default = REGMAP_ENDIAN_NATIVE, 212 }; 213 214 struct regmap *__regmap_init_spmi_ext(struct spmi_device *sdev, 215 const struct regmap_config *config, 216 struct lock_class_key *lock_key, 217 const char *lock_name) 218 { 219 return __regmap_init(&sdev->dev, ®map_spmi_ext, sdev, config, 220 lock_key, lock_name); 221 } 222 EXPORT_SYMBOL_GPL(__regmap_init_spmi_ext); 223 224 struct regmap *__devm_regmap_init_spmi_ext(struct spmi_device *sdev, 225 const struct regmap_config *config, 226 struct lock_class_key *lock_key, 227 const char *lock_name) 228 { 229 return __devm_regmap_init(&sdev->dev, ®map_spmi_ext, sdev, config, 230 lock_key, lock_name); 231 } 232 EXPORT_SYMBOL_GPL(__devm_regmap_init_spmi_ext); 233 234 MODULE_LICENSE("GPL"); 235