From dccd573bb02aa011a4a7146c02c409ac0bd722a0 Mon Sep 17 00:00:00 2001 From: David Brownell Date: Tue, 17 Jul 2007 04:04:02 -0700 Subject: SPI controller drivers: check for unsupported modes Minor SPI controller driver updates: make the setup() methods reject spi->mode bits they don't support, by masking aginst the inverse of bits they *do* support. This insures against misbehavior later when new mode bits get added. Most controllers can't support SPI_LSB_FIRST; more handle SPI_CS_HIGH. Support for all four SPI clock/transfer modes is routine. Signed-off-by: David Brownell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/spi/spi_bitbang.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) (limited to 'drivers/spi/spi_bitbang.c') diff --git a/drivers/spi/spi_bitbang.c b/drivers/spi/spi_bitbang.c index 88425e1af4d3..0c85c984ccb4 100644 --- a/drivers/spi/spi_bitbang.c +++ b/drivers/spi/spi_bitbang.c @@ -187,12 +187,10 @@ int spi_bitbang_setup(struct spi_device *spi) bitbang = spi_master_get_devdata(spi->master); - /* REVISIT: some systems will want to support devices using lsb-first - * bit encodings on the wire. In pure software that would be trivial, - * just bitbang_txrx_le_cphaX() routines shifting the other way, and - * some hardware controllers also have this support. + /* Bitbangers can support SPI_CS_HIGH, SPI_3WIRE, and so on; + * add those to master->flags, and provide the other support. */ - if ((spi->mode & SPI_LSB_FIRST) != 0) + if ((spi->mode & ~(SPI_CPOL|SPI_CPHA|bitbang->flags)) != 0) return -EINVAL; if (!cs) { -- cgit v1.2.3