diff options
Diffstat (limited to 'drivers/base/regmap/regmap-fsi.c')
-rw-r--r-- | drivers/base/regmap/regmap-fsi.c | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/drivers/base/regmap/regmap-fsi.c b/drivers/base/regmap/regmap-fsi.c new file mode 100644 index 000000000000..3d2f3cb31d5e --- /dev/null +++ b/drivers/base/regmap/regmap-fsi.c @@ -0,0 +1,231 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Register map access API - FSI support +// +// Copyright 2022 IBM Corp +// +// Author: Eddie James <eajames@linux.ibm.com> + +#include <linux/fsi.h> +#include <linux/module.h> +#include <linux/regmap.h> + +#include "internal.h" + +static int regmap_fsi32_reg_read(void *context, unsigned int reg, unsigned int *val) +{ + u32 v; + int ret; + + ret = fsi_slave_read(context, reg, &v, sizeof(v)); + if (ret) + return ret; + + *val = v; + return 0; +} + +static int regmap_fsi32_reg_write(void *context, unsigned int reg, unsigned int val) +{ + u32 v = val; + + return fsi_slave_write(context, reg, &v, sizeof(v)); +} + +static const struct regmap_bus regmap_fsi32 = { + .reg_write = regmap_fsi32_reg_write, + .reg_read = regmap_fsi32_reg_read, +}; + +static int regmap_fsi32le_reg_read(void *context, unsigned int reg, unsigned int *val) +{ + __be32 v; + int ret; + + ret = fsi_slave_read(context, reg, &v, sizeof(v)); + if (ret) + return ret; + + *val = be32_to_cpu(v); + return 0; +} + +static int regmap_fsi32le_reg_write(void *context, unsigned int reg, unsigned int val) +{ + __be32 v = cpu_to_be32(val); + + return fsi_slave_write(context, reg, &v, sizeof(v)); +} + +static const struct regmap_bus regmap_fsi32le = { + .reg_write = regmap_fsi32le_reg_write, + .reg_read = regmap_fsi32le_reg_read, +}; + +static int regmap_fsi16_reg_read(void *context, unsigned int reg, unsigned int *val) +{ + u16 v; + int ret; + + ret = fsi_slave_read(context, reg, &v, sizeof(v)); + if (ret) + return ret; + + *val = v; + return 0; +} + +static int regmap_fsi16_reg_write(void *context, unsigned int reg, unsigned int val) +{ + u16 v; + + if (val > 0xffff) + return -EINVAL; + + v = val; + return fsi_slave_write(context, reg, &v, sizeof(v)); +} + +static const struct regmap_bus regmap_fsi16 = { + .reg_write = regmap_fsi16_reg_write, + .reg_read = regmap_fsi16_reg_read, +}; + +static int regmap_fsi16le_reg_read(void *context, unsigned int reg, unsigned int *val) +{ + __be16 v; + int ret; + + ret = fsi_slave_read(context, reg, &v, sizeof(v)); + if (ret) + return ret; + + *val = be16_to_cpu(v); + return 0; +} + +static int regmap_fsi16le_reg_write(void *context, unsigned int reg, unsigned int val) +{ + __be16 v; + + if (val > 0xffff) + return -EINVAL; + + v = cpu_to_be16(val); + return fsi_slave_write(context, reg, &v, sizeof(v)); +} + +static const struct regmap_bus regmap_fsi16le = { + .reg_write = regmap_fsi16le_reg_write, + .reg_read = regmap_fsi16le_reg_read, +}; + +static int regmap_fsi8_reg_read(void *context, unsigned int reg, unsigned int *val) +{ + u8 v; + int ret; + + ret = fsi_slave_read(context, reg, &v, sizeof(v)); + if (ret) + return ret; + + *val = v; + return 0; +} + +static int regmap_fsi8_reg_write(void *context, unsigned int reg, unsigned int val) +{ + u8 v; + + if (val > 0xff) + return -EINVAL; + + v = val; + return fsi_slave_write(context, reg, &v, sizeof(v)); +} + +static const struct regmap_bus regmap_fsi8 = { + .reg_write = regmap_fsi8_reg_write, + .reg_read = regmap_fsi8_reg_read, +}; + +static const struct regmap_bus *regmap_get_fsi_bus(struct fsi_device *fsi_dev, + const struct regmap_config *config) +{ + const struct regmap_bus *bus = NULL; + + if (config->reg_bits == 8 || config->reg_bits == 16 || config->reg_bits == 32) { + switch (config->val_bits) { + case 8: + bus = ®map_fsi8; + break; + case 16: + switch (regmap_get_val_endian(&fsi_dev->dev, NULL, config)) { + case REGMAP_ENDIAN_LITTLE: +#ifdef __LITTLE_ENDIAN + case REGMAP_ENDIAN_NATIVE: +#endif + bus = ®map_fsi16le; + break; + case REGMAP_ENDIAN_DEFAULT: + case REGMAP_ENDIAN_BIG: +#ifdef __BIG_ENDIAN + case REGMAP_ENDIAN_NATIVE: +#endif + bus = ®map_fsi16; + break; + default: + break; + } + break; + case 32: + switch (regmap_get_val_endian(&fsi_dev->dev, NULL, config)) { + case REGMAP_ENDIAN_LITTLE: +#ifdef __LITTLE_ENDIAN + case REGMAP_ENDIAN_NATIVE: +#endif + bus = ®map_fsi32le; + break; + case REGMAP_ENDIAN_DEFAULT: + case REGMAP_ENDIAN_BIG: +#ifdef __BIG_ENDIAN + case REGMAP_ENDIAN_NATIVE: +#endif + bus = ®map_fsi32; + break; + default: + break; + } + break; + } + } + + return bus ?: ERR_PTR(-EOPNOTSUPP); +} + +struct regmap *__regmap_init_fsi(struct fsi_device *fsi_dev, const struct regmap_config *config, + struct lock_class_key *lock_key, const char *lock_name) +{ + const struct regmap_bus *bus = regmap_get_fsi_bus(fsi_dev, config); + + if (IS_ERR(bus)) + return ERR_CAST(bus); + + return __regmap_init(&fsi_dev->dev, bus, fsi_dev->slave, config, lock_key, lock_name); +} +EXPORT_SYMBOL_GPL(__regmap_init_fsi); + +struct regmap *__devm_regmap_init_fsi(struct fsi_device *fsi_dev, + const struct regmap_config *config, + struct lock_class_key *lock_key, const char *lock_name) +{ + const struct regmap_bus *bus = regmap_get_fsi_bus(fsi_dev, config); + + if (IS_ERR(bus)) + return ERR_CAST(bus); + + return __devm_regmap_init(&fsi_dev->dev, bus, fsi_dev->slave, config, lock_key, lock_name); +} +EXPORT_SYMBOL_GPL(__devm_regmap_init_fsi); + +MODULE_LICENSE("GPL"); |