diff options
Diffstat (limited to 'kernel/drivers/base/regmap/regmap-spi.c')
-rw-r--r-- | kernel/drivers/base/regmap/regmap-spi.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/kernel/drivers/base/regmap/regmap-spi.c b/kernel/drivers/base/regmap/regmap-spi.c new file mode 100644 index 000000000..53d1148e8 --- /dev/null +++ b/kernel/drivers/base/regmap/regmap-spi.c @@ -0,0 +1,149 @@ +/* + * Register map access API - SPI support + * + * Copyright 2011 Wolfson Microelectronics plc + * + * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#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 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, +}; + +/** + * regmap_init_spi(): Initialise register map + * + * @spi: Device that will be interacted with + * @config: Configuration for register map + * + * The return value will be an ERR_PTR() on error or a valid pointer to + * a struct regmap. + */ +struct regmap *regmap_init_spi(struct spi_device *spi, + const struct regmap_config *config) +{ + return regmap_init(&spi->dev, ®map_spi, &spi->dev, config); +} +EXPORT_SYMBOL_GPL(regmap_init_spi); + +/** + * devm_regmap_init_spi(): Initialise register map + * + * @spi: Device that will be interacted with + * @config: Configuration for register map + * + * The return value will be an ERR_PTR() on error or a valid pointer + * to a struct regmap. The map will be automatically freed by the + * device management code. + */ +struct regmap *devm_regmap_init_spi(struct spi_device *spi, + const struct regmap_config *config) +{ + return devm_regmap_init(&spi->dev, ®map_spi, &spi->dev, config); +} +EXPORT_SYMBOL_GPL(devm_regmap_init_spi); + +MODULE_LICENSE("GPL"); |