At present it is difficult to extend the SPI structure since all drivers allocate it themselves, and few of them zero all fields. Add a new function spi_alloc_slave() which can be used by SPI drivers to perform this allocation, and thus ensure that all drivers can better cope with SPI structure changes.
Signed-off-by: Simon Glass sjg@chromium.org --- drivers/spi/Makefile | 3 +++ drivers/spi/spi.c | 39 +++++++++++++++++++++++++++++++++++++++ include/spi.h | 41 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 83 insertions(+), 0 deletions(-) create mode 100644 drivers/spi/spi.c
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 824d357..4e8de5d 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -25,6 +25,9 @@ include $(TOPDIR)/config.mk
LIB := $(obj)libspi.o
+# There are many options which enable SPI, so make this library available +COBJS-y += spi.o + COBJS-$(CONFIG_ALTERA_SPI) += altera_spi.o COBJS-$(CONFIG_ANDES_SPI) += andes_spi.o COBJS-$(CONFIG_ARMADA100_SPI) += armada100_spi.o diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c new file mode 100644 index 0000000..cb36c5e --- /dev/null +++ b/drivers/spi/spi.c @@ -0,0 +1,39 @@ +/* + * Copyright (c) 2011 The Chromium OS Authors. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but without any warranty; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> +#include <malloc.h> +#include <spi.h> + +void *spi_do_alloc_slave(int offset, int size, unsigned int bus, + unsigned int cs) +{ + struct spi_slave *slave; + void *ptr; + + ptr = malloc(size); + if (ptr) { + memset(ptr, '\0', size); + slave = (struct spi_slave *)(ptr + offset); + slave->bus = bus; + slave->cs = cs; + } + + return ptr; +} diff --git a/include/spi.h b/include/spi.h index 60e85db..ebc9652 100644 --- a/include/spi.h +++ b/include/spi.h @@ -62,6 +62,47 @@ struct spi_slave { */ void spi_init(void);
+/** + * spi_do_alloc_slave - Allocate a new SPI slave (internal) + * + * Allocate and zero all fields in the spi slave, and set the bus/chip + * select. Use the helper macro spi_alloc_slave() to call this. + * + * @offset: Offset of struct spi_slave within slave structure + * @size: Size of slave structure + * @bus: Bus ID of the slave chip. + * @cs: Chip select ID of the slave chip on the specified bus. + */ +void *spi_do_alloc_slave(int offset, int size, unsigned int bus, + unsigned int cs); + +/** + * spi_alloc_slave - Allocate a new SPI slave + * + * Allocate and zero all fields in the spi slave, and set the bus/chip + * select. + * + * @_struct: Name of structure to allocate (e.g. struct tegra_spi). This + * structure must contain a member 'struct spi_slave *slave'. + * @bus: Bus ID of the slave chip. + * @cs: Chip select ID of the slave chip on the specified bus. + */ +#define spi_alloc_slave(_struct, bus, cs) \ + spi_do_alloc_slave(offsetof(_struct, slave), \ + sizeof(_struct), bus, cs) + +/** + * spi_alloc_slave_base - Allocate a new SPI slave with no private data + * + * Allocate and zero all fields in the spi slave, and set the bus/chip + * select. + * + * @bus: Bus ID of the slave chip. + * @cs: Chip select ID of the slave chip on the specified bus. + */ +#define spi_alloc_slave_base(bus, cs) \ + spi_do_alloc_slave(0, sizeof(struct spi_slave), bus, cs) + /*----------------------------------------------------------------------- * Set up communications parameters for a SPI slave. *