Messages in this thread Patch in this message | | | From | Mark Brown <> | Subject | [PATCH 3/4] regmap: Add SPI bus support | Date | Fri, 15 Jul 2011 15:23:11 +0900 |
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We initialise at postcore_initcall() so that we are available before users - some users such as PMICs initialise very early. We won't actually try to use any of the bus until a device initialises a register map.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Liam Girdwood <lrg@ti.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de> --- drivers/spi/Kconfig | 4 ++ drivers/spi/Makefile | 1 + drivers/spi/spi-regmap.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 81 insertions(+), 0 deletions(-) create mode 100644 drivers/spi/spi-regmap.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index de35c3a..1c689a8 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -43,12 +43,16 @@ config SPI_MASTER # boolean "SPI Master Support" boolean default SPI + select SPI_REGMAP if REGMAP help If your system has an master-capable SPI controller (which provides the clock and chipselect), you can enable that controller and the protocol drivers for the SPI slave chips that are connected. +config SPI_REGMAP + boolean + if SPI_MASTER comment "SPI Master Controller Drivers" diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 0f8c69b..52dcf27 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -7,6 +7,7 @@ ccflags-$(CONFIG_SPI_DEBUG) := -DDEBUG # small core, mostly translating board-specific # config declarations into driver model code obj-$(CONFIG_SPI_MASTER) += spi.o +obj-$(CONFIG_SPI_REGMAP) += spi-regmap.o # SPI master controller drivers (bus) obj-$(CONFIG_SPI_ALTERA) += spi_altera.o diff --git a/drivers/spi/spi-regmap.c b/drivers/spi/spi-regmap.c new file mode 100644 index 0000000..ea9072e --- /dev/null +++ b/drivers/spi/spi-regmap.c @@ -0,0 +1,76 @@ +/* + * 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]; + + spi_message_init(&m); + + memset(&t, 0, sizeof(t)); + + t[0].tx_buf = reg; + t[0].len = reg_len; + spi_message_add_tail(&t[0], &m); + + t[1].tx_buf = val; + t[1].len = val_len; + 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, +}; + +static int __init regmap_spi_init(void) +{ + regmap_add_bus(®map_spi); + return 0; +} +postcore_initcall(regmap_spi_init); + +static void __exit regmap_spi_exit(void) +{ + regmap_del_bus(®map_spi); +} +module_exit(regmap_spi_exit); -- 1.7.5.4
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