linux/drivers/base/regmap/regmap-fsi.c
Eddie James bf0d29fb51
regmap: Add FSI bus support
Add regmap support for the FSI bus.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20221102205148.1334459-2-eajames@linux.ibm.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2022-11-25 19:17:02 +00:00

232 lines
4.8 KiB
C

// 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 = &regmap_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 = &regmap_fsi16le;
break;
case REGMAP_ENDIAN_DEFAULT:
case REGMAP_ENDIAN_BIG:
#ifdef __BIG_ENDIAN
case REGMAP_ENDIAN_NATIVE:
#endif
bus = &regmap_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 = &regmap_fsi32le;
break;
case REGMAP_ENDIAN_DEFAULT:
case REGMAP_ENDIAN_BIG:
#ifdef __BIG_ENDIAN
case REGMAP_ENDIAN_NATIVE:
#endif
bus = &regmap_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");