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_s3c24xx.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'drivers/spi/spi_s3c24xx.c') diff --git a/drivers/spi/spi_s3c24xx.c b/drivers/spi/spi_s3c24xx.c index d5a710f..7071ff8 100644 --- a/drivers/spi/spi_s3c24xx.c +++ b/drivers/spi/spi_s3c24xx.c @@ -146,6 +146,9 @@ static int s3c24xx_spi_setupxfer(struct spi_device *spi, return 0; } +/* the spi->mode bits understood by this driver: */ +#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH) + static int s3c24xx_spi_setup(struct spi_device *spi) { int ret; @@ -153,8 +156,11 @@ static int s3c24xx_spi_setup(struct spi_device *spi) if (!spi->bits_per_word) spi->bits_per_word = 8; - if ((spi->mode & SPI_LSB_FIRST) != 0) + if (spi->mode & ~MODEBITS) { + dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n", + spi->mode & ~MODEBITS); return -EINVAL; + } ret = s3c24xx_spi_setupxfer(spi, NULL); if (ret < 0) { -- cgit v1.1