1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright(c) 2015-17 Intel Corporation. 3 4 #include <linux/device.h> 5 #include <linux/errno.h> 6 #include <linux/module.h> 7 #include <linux/regmap.h> 8 #include <linux/soundwire/sdw.h> 9 #include <linux/types.h> 10 #include "internal.h" 11 12 static int regmap_sdw_write(void *context, const void *val_buf, size_t val_size) 13 { 14 struct device *dev = context; 15 struct sdw_slave *slave = dev_to_sdw_dev(dev); 16 /* First word of buffer contains the destination address */ 17 u32 addr = le32_to_cpu(*(const __le32 *)val_buf); 18 const u8 *val = val_buf; 19 20 return sdw_nwrite_no_pm(slave, addr, val_size - sizeof(addr), val + sizeof(addr)); 21 } 22 23 static int regmap_sdw_gather_write(void *context, 24 const void *reg_buf, size_t reg_size, 25 const void *val_buf, size_t val_size) 26 { 27 struct device *dev = context; 28 struct sdw_slave *slave = dev_to_sdw_dev(dev); 29 u32 addr = le32_to_cpu(*(const __le32 *)reg_buf); 30 31 return sdw_nwrite_no_pm(slave, addr, val_size, val_buf); 32 } 33 34 static int regmap_sdw_read(void *context, 35 const void *reg_buf, size_t reg_size, 36 void *val_buf, size_t val_size) 37 { 38 struct device *dev = context; 39 struct sdw_slave *slave = dev_to_sdw_dev(dev); 40 u32 addr = le32_to_cpu(*(const __le32 *)reg_buf); 41 42 return sdw_nread_no_pm(slave, addr, val_size, val_buf); 43 } 44 45 static const struct regmap_bus regmap_sdw = { 46 .write = regmap_sdw_write, 47 .gather_write = regmap_sdw_gather_write, 48 .read = regmap_sdw_read, 49 .reg_format_endian_default = REGMAP_ENDIAN_LITTLE, 50 .val_format_endian_default = REGMAP_ENDIAN_LITTLE, 51 }; 52 53 static int regmap_sdw_config_check(const struct regmap_config *config) 54 { 55 /* Register addresses are 32 bits wide */ 56 if (config->reg_bits != 32) 57 return -ENOTSUPP; 58 59 if (config->pad_bits != 0) 60 return -ENOTSUPP; 61 62 /* Only bulk writes are supported not multi-register writes */ 63 if (config->can_multi_write) 64 return -ENOTSUPP; 65 66 return 0; 67 } 68 69 struct regmap *__regmap_init_sdw(struct sdw_slave *sdw, 70 const struct regmap_config *config, 71 struct lock_class_key *lock_key, 72 const char *lock_name) 73 { 74 int ret; 75 76 ret = regmap_sdw_config_check(config); 77 if (ret) 78 return ERR_PTR(ret); 79 80 return __regmap_init(&sdw->dev, ®map_sdw, 81 &sdw->dev, config, lock_key, lock_name); 82 } 83 EXPORT_SYMBOL_GPL(__regmap_init_sdw); 84 85 struct regmap *__devm_regmap_init_sdw(struct sdw_slave *sdw, 86 const struct regmap_config *config, 87 struct lock_class_key *lock_key, 88 const char *lock_name) 89 { 90 int ret; 91 92 ret = regmap_sdw_config_check(config); 93 if (ret) 94 return ERR_PTR(ret); 95 96 return __devm_regmap_init(&sdw->dev, ®map_sdw, 97 &sdw->dev, config, lock_key, lock_name); 98 } 99 EXPORT_SYMBOL_GPL(__devm_regmap_init_sdw); 100 101 MODULE_DESCRIPTION("Regmap SoundWire Module"); 102 MODULE_LICENSE("GPL v2"); 103