diff options
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spidev.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c index 5d869c4..606e7a4 100644 --- a/drivers/spi/spidev.c +++ b/drivers/spi/spidev.c @@ -58,15 +58,20 @@ static unsigned long minors[N_SPI_MINORS / BITS_PER_LONG]; /* 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. + * settings for some settings can cause *lots* of trouble for other + * devices on a shared bus: * - * REVISIT should changing those two modes be privileged? + * - CS_HIGH ... this device will be active when it shouldn't be + * - 3WIRE ... when active, it won't behave as it should + * - NO_CS ... there will be no explicit message boundaries; this + * is completely incompatible with the shared bus model + * - READY ... transfers may proceed when they shouldn't. + * + * REVISIT should changing those flags be privileged? */ #define SPI_MODE_MASK (SPI_CPHA | SPI_CPOL | SPI_CS_HIGH \ - | SPI_LSB_FIRST | SPI_3WIRE | SPI_LOOP) + | SPI_LSB_FIRST | SPI_3WIRE | SPI_LOOP \ + | SPI_NO_CS | SPI_READY) struct spidev_data { dev_t devt; |