blob: 37ab23a9d0345a12991e3b273e3d009b147ce4bc [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
//
// Register map access API - SPI support
//
// Copyright 2011 Wolfson Microelectronics plc
//
// Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
#include <linux/regmap.h>
#include <linux/spi/spi.h>
#include <linux/module.h>
#include "internal.h"
struct regmap_async_spi {
struct regmap_async core;
struct spi_message m;
struct spi_transfer t[2];
};
static void regmap_spi_complete(void *data)
{
struct regmap_async_spi *async = data;
regmap_async_complete_cb(&async->core, async->m.status);
}
static int regmap_spi_write(void *context, const void *data, size_t count)
{
struct device *dev = context;
struct spi_device *spi = to_spi_device(dev);
return spi_write(spi, data, count);
}
static int regmap_spi_gather_write(void *context,
const void *reg, size_t reg_len,
const void *val, size_t val_len)
{
struct device *dev = context;
struct spi_device *spi = to_spi_device(dev);
struct spi_message m;
struct spi_transfer t[2] = { { .tx_buf = reg, .len = reg_len, },
{ .tx_buf = val, .len = val_len, }, };
spi_message_init(&m);
spi_message_add_tail(&t[0], &m);
spi_message_add_tail(&t[1], &m);
return spi_sync(spi, &m);
}
static int regmap_spi_async_write(void *context,
const void *reg, size_t reg_len,
const void *val, size_t val_len,
struct regmap_async *a)
{
struct regmap_async_spi *async = container_of(a,
struct regmap_async_spi,
core);
struct device *dev = context;
struct spi_device *spi = to_spi_device(dev);
async->t[0].tx_buf = reg;
async->t[0].len = reg_len;
async->t[1].tx_buf = val;
async->t[1].len = val_len;
spi_message_init(&async->m);
spi_message_add_tail(&async->t[0], &async->m);
if (val)
spi_message_add_tail(&async->t[1], &async->m);
async->m.complete = regmap_spi_complete;
async->m.context = async;
return spi_async(spi, &async->m);
}
static struct regmap_async *regmap_spi_async_alloc(void)
{
struct regmap_async_spi *async_spi;
async_spi = kzalloc(sizeof(*async_spi), GFP_KERNEL);
if (!async_spi)
return NULL;
return &async_spi->core;
}
static int regmap_spi_read(void *context,
const void *reg, size_t reg_size,
void *val, size_t val_size)
{
struct device *dev = context;
struct spi_device *spi = to_spi_device(dev);
return spi_write_then_read(spi, reg, reg_size, val, val_size);
}
static const struct regmap_bus regmap_spi = {
.write = regmap_spi_write,
.gather_write = regmap_spi_gather_write,
.async_write = regmap_spi_async_write,
.async_alloc = regmap_spi_async_alloc,
.read = regmap_spi_read,
.read_flag_mask = 0x80,
.reg_format_endian_default = REGMAP_ENDIAN_BIG,
.val_format_endian_default = REGMAP_ENDIAN_BIG,
};
static const struct regmap_bus *regmap_get_spi_bus(struct spi_device *spi,
const struct regmap_config *config)
{
size_t max_size = spi_max_transfer_size(spi);
size_t max_msg_size, reg_reserve_size;
struct regmap_bus *bus;
if (max_size != SIZE_MAX) {
bus = kmemdup(&regmap_spi, sizeof(*bus), GFP_KERNEL);
if (!bus)
return ERR_PTR(-ENOMEM);
max_msg_size = spi_max_message_size(spi);
reg_reserve_size = config->reg_bits / BITS_PER_BYTE
+ config->pad_bits / BITS_PER_BYTE;
if (max_size + reg_reserve_size > max_msg_size)
max_size -= reg_reserve_size;
bus->free_on_exit = true;
bus->max_raw_read = max_size;
bus->max_raw_write = max_size;
return bus;
}
return &regmap_spi;
}
struct regmap *__regmap_init_spi(struct spi_device *spi,
const struct regmap_config *config,
struct lock_class_key *lock_key,
const char *lock_name)
{
const struct regmap_bus *bus = regmap_get_spi_bus(spi, config);
if (IS_ERR(bus))
return ERR_CAST(bus);
return __regmap_init(&spi->dev, bus, &spi->dev, config, lock_key, lock_name);
}
EXPORT_SYMBOL_GPL(__regmap_init_spi);
struct regmap *__devm_regmap_init_spi(struct spi_device *spi,
const struct regmap_config *config,
struct lock_class_key *lock_key,
const char *lock_name)
{
const struct regmap_bus *bus = regmap_get_spi_bus(spi, config);
if (IS_ERR(bus))
return ERR_CAST(bus);
return __devm_regmap_init(&spi->dev, bus, &spi->dev, config, lock_key, lock_name);
}
EXPORT_SYMBOL_GPL(__devm_regmap_init_spi);
MODULE_LICENSE("GPL");