diff options
| -rw-r--r-- | drivers/spi/spi.c | 8 | ||||
| -rw-r--r-- | include/linux/spi/spi.h | 1 |
2 files changed, 9 insertions, 0 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 7e8ffe3fdc00..cfa3c3decb8a 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1111,6 +1111,7 @@ static void _spi_transfer_cs_change_delay(struct spi_message *msg, { u32 delay = xfer->cs_change_delay; u32 unit = xfer->cs_change_delay_unit; + u32 hz; /* return early on "fast" mode - for everything but USECS */ if (!delay && unit != SPI_DELAY_UNIT_USECS) @@ -1126,6 +1127,13 @@ static void _spi_transfer_cs_change_delay(struct spi_message *msg, break; case SPI_DELAY_UNIT_NSECS: /* nothing to do here */ break; + case SPI_DELAY_UNIT_SCK: + /* if there is no effective speed know, then approximate + * by underestimating with half the requested hz + */ + hz = xfer->effective_speed_hz ?: xfer->speed_hz / 2; + delay *= DIV_ROUND_UP(1000000000, hz); + break; default: dev_err_once(&msg->spi->dev, "Use of unsupported delay unit %i, using default of 10us\n", diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index 023beb9e9e4b..e552a036cb4d 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -831,6 +831,7 @@ struct spi_transfer { u8 cs_change_delay_unit; #define SPI_DELAY_UNIT_USECS 0 #define SPI_DELAY_UNIT_NSECS 1 +#define SPI_DELAY_UNIT_SCK 2 u32 speed_hz; u16 word_delay; |