diff options
Diffstat (limited to 'drivers/base/regmap/regmap-spi.c')
-rw-r--r-- | drivers/base/regmap/regmap-spi.c | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/drivers/base/regmap/regmap-spi.c b/drivers/base/regmap/regmap-spi.c new file mode 100644 index 00000000000..4deba0621bc --- /dev/null +++ b/drivers/base/regmap/regmap-spi.c @@ -0,0 +1,72 @@ +/* + * 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/init.h> + +static int regmap_spi_write(struct device *dev, const void *data, size_t count) +{ + struct spi_device *spi = to_spi_device(dev); + + return spi_write(spi, data, count); +} + +static int regmap_spi_gather_write(struct device *dev, + const void *reg, size_t reg_len, + const void *val, size_t val_len) +{ + 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_read(struct device *dev, + const void *reg, size_t reg_size, + void *val, size_t val_size) +{ + 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 = { + .type = &spi_bus_type, + .write = regmap_spi_write, + .gather_write = regmap_spi_gather_write, + .read = regmap_spi_read, + .owner = THIS_MODULE, + .read_flag_mask = 0x80, +}; + +/** + * 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, config); +} +EXPORT_SYMBOL_GPL(regmap_init_spi); |