diff options
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spidev.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c index 38b60ad0eda0..630f781aeb19 100644 --- a/drivers/spi/spidev.c +++ b/drivers/spi/spidev.c @@ -55,9 +55,16 @@ static unsigned long minors[N_SPI_MINORS / BITS_PER_LONG]; -/* Bit masks for spi_device.mode management */ -#define SPI_MODE_MASK (SPI_CPHA | SPI_CPOL) - +/* Bit masks for spi_device.mode management. Note that incorrect + * settings for CS_HIGH and 3WIRE can cause *lots* of trouble for other + * devices on a shared bus: CS_HIGH, because this device will be + * active when it shouldn't be; 3WIRE, because when active it won't + * behave as it should. + * + * REVISIT should changing those two modes be privileged? + */ +#define SPI_MODE_MASK (SPI_CPHA | SPI_CPOL | SPI_CS_HIGH \ + | SPI_LSB_FIRST | SPI_3WIRE | SPI_LOOP) struct spidev_data { struct device dev; |