diff options
| author | David Brownell <david-b@pacbell.net> | 2007-07-17 04:04:02 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-07-17 10:23:04 -0700 |
| commit | dccd573bb02aa011a4a7146c02c409ac0bd722a0 (patch) | |
| tree | 743eeca4fbbea8272ca4f341b806d776e404d704 /drivers/spi/spi_s3c24xx.c | |
| parent | ff294cba8a62fa8334b88692da6d48683900f015 (diff) | |
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 <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/spi/spi_s3c24xx.c')
| -rw-r--r-- | drivers/spi/spi_s3c24xx.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/drivers/spi/spi_s3c24xx.c b/drivers/spi/spi_s3c24xx.c index d5a710f6e44..7071ff8da63 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) { |