From: Martin Sperl <[email protected]> The official documentation is wrong in this respect. Has been tested empirically for dividers 2-1024
Signed-off-by: Martin Sperl <[email protected]> --- drivers/spi/spi-bcm2835.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c index e1dea40..779e3a8 100644 --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -192,8 +192,9 @@ static int bcm2835_spi_start_transfer( if (spi_hz >= clk_hz / 2) { cdiv = 2; /* clk_hz/2 is the fastest we can go */ } else if (spi_hz) { - /* CDIV must be a power of two */ - cdiv = roundup_pow_of_two(DIV_ROUND_UP(clk_hz, spi_hz)); + /* CDIV must be a multiple of two */ + cdiv = DIV_ROUND_UP(clk_hz, spi_hz); + cdiv += (cdiv % 2); if (cdiv >= 65536) cdiv = 0; /* 0 is the slowest we can go */ -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
