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/au1550_spi.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'drivers/spi/au1550_spi.c') diff --git a/drivers/spi/au1550_spi.c b/drivers/spi/au1550_spi.c index ae2b1af0dba..c47a650183a 100644 --- a/drivers/spi/au1550_spi.c +++ b/drivers/spi/au1550_spi.c @@ -280,6 +280,9 @@ static int au1550_spi_setupxfer(struct spi_device *spi, struct spi_transfer *t) return 0; } +/* the spi->mode bits understood by this driver: */ +#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST) + static int au1550_spi_setup(struct spi_device *spi) { struct au1550_spi *hw = spi_master_get_devdata(spi->master); @@ -292,6 +295,12 @@ static int au1550_spi_setup(struct spi_device *spi) return -EINVAL; } + if (spi->mode & ~MODEBITS) { + dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n", + spi->mode & ~MODEBITS); + return -EINVAL; + } + if (spi->max_speed_hz == 0) spi->max_speed_hz = hw->freq_max; if (spi->max_speed_hz > hw->freq_max -- cgit v1.2.3