// SPDX-License-Identifier: GPL-2.0
// Copyright(c) 2015-17 Intel Corporation.

#include <linux/device.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/soundwire/sdw.h>
#include <linux/types.h>
#include "internal.h"

static int regmap_sdw_write(void *context, const void *val_buf, size_t val_size)
{
        struct device *dev = context;
        struct sdw_slave *slave = dev_to_sdw_dev(dev);
        /* First word of buffer contains the destination address */
        u32 addr = le32_to_cpu(*(const __le32 *)val_buf);
        const u8 *val = val_buf;

        return sdw_nwrite_no_pm(slave, addr, val_size - sizeof(addr), val + sizeof(addr));
}

static int regmap_sdw_gather_write(void *context,
                                   const void *reg_buf, size_t reg_size,
                                   const void *val_buf, size_t val_size)
{
        struct device *dev = context;
        struct sdw_slave *slave = dev_to_sdw_dev(dev);
        u32 addr = le32_to_cpu(*(const __le32 *)reg_buf);

        return sdw_nwrite_no_pm(slave, addr, val_size, val_buf);
}

static int regmap_sdw_read(void *context,
                           const void *reg_buf, size_t reg_size,
                           void *val_buf, size_t val_size)
{
        struct device *dev = context;
        struct sdw_slave *slave = dev_to_sdw_dev(dev);
        u32 addr = le32_to_cpu(*(const __le32 *)reg_buf);

        return sdw_nread_no_pm(slave, addr, val_size, val_buf);
}

static const struct regmap_bus regmap_sdw = {
        .write = regmap_sdw_write,
        .gather_write = regmap_sdw_gather_write,
        .read = regmap_sdw_read,
        .reg_format_endian_default = REGMAP_ENDIAN_LITTLE,
        .val_format_endian_default = REGMAP_ENDIAN_LITTLE,
};

static int regmap_sdw_config_check(const struct regmap_config *config)
{
        /* Register addresses are 32 bits wide */
        if (config->reg_bits != 32)
                return -ENOTSUPP;

        if (config->pad_bits != 0)
                return -ENOTSUPP;

        /* Only bulk writes are supported not multi-register writes */
        if (config->can_multi_write)
                return -ENOTSUPP;

        return 0;
}

struct regmap *__regmap_init_sdw(struct sdw_slave *sdw,
                                 const struct regmap_config *config,
                                 struct lock_class_key *lock_key,
                                 const char *lock_name)
{
        int ret;

        ret = regmap_sdw_config_check(config);
        if (ret)
                return ERR_PTR(ret);

        return __regmap_init(&sdw->dev, &regmap_sdw,
                        &sdw->dev, config, lock_key, lock_name);
}
EXPORT_SYMBOL_GPL(__regmap_init_sdw);

struct regmap *__devm_regmap_init_sdw(struct sdw_slave *sdw,
                                      const struct regmap_config *config,
                                      struct lock_class_key *lock_key,
                                      const char *lock_name)
{
        int ret;

        ret = regmap_sdw_config_check(config);
        if (ret)
                return ERR_PTR(ret);

        return __devm_regmap_init(&sdw->dev, &regmap_sdw,
                        &sdw->dev, config, lock_key, lock_name);
}
EXPORT_SYMBOL_GPL(__devm_regmap_init_sdw);

MODULE_DESCRIPTION("regmap SoundWire Module");
MODULE_LICENSE("GPL v2");