This patch adds a new flags argument to bitbang_txrx_be_cpha0 and
bitbang_txrx_be_cpha1 transfer functions. This enables support for
SPI_MASTER_NO_{TX,RX} transfer modes. The change should have no impact
on speed of the existing drivers. bitbank_txrx_* functions are usually
inlined into the drivers. When the argument is equal to constant zero,
the optimizer would be able to eliminate the dead code (flags checks)
easily. Tested on ARM and GCC 4.4.x and in all cases the checks were
eliminated in the inlined function.
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
A number of files in drivers/spi fail checkincludes.pl due to the double
include of <linux/spi/spi_bitbang.h>.
The first include is needed to get the struct spi_bitbang definition and
the spi_bitbang_* function prototypes.
The second include happens after defining EXPAND_BITBANG_TXRX to get the
inlined bitbang_txrx_* utility functions.
The <linux/spi/spi_bitbang.h> header is also included by a number of other
spi drivers, as well as some arch/ code, in order to use struct spi_bitbang
and the associated functions.
To fix the double include, and remove any potential confusion about it, move
the inlined bitbang_txrx_* functions to a new private header in drivers/spi
and also remove the need to define EXPAND_BITBANG_TXRX.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Marek Szyprowski