From: Xu Yilun yilun.xu@intel.com
[ Upstream commit 6170d077bf92c5b3dfbe1021688d3c0404f7c9e9 ]
The xfer waiting time is the result of xfer->len / xfer->speed_hz. This patch makes the assumption of 100khz xfer speed if the xfer->speed_hz is not assigned and stays 0. This avoids the divide by 0 issue and ensures a reasonable tolerant waiting time.
Signed-off-by: Xu Yilun yilun.xu@intel.com Link: https://lore.kernel.org/r/1609723749-3557-1-git-send-email-yilun.xu@intel.co... Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/spi.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 2eaa7dbb70108..7694e1ae5b0b2 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1100,6 +1100,7 @@ static int spi_transfer_wait(struct spi_controller *ctlr, { struct spi_statistics *statm = &ctlr->statistics; struct spi_statistics *stats = &msg->spi->statistics; + u32 speed_hz = xfer->speed_hz; unsigned long long ms;
if (spi_controller_is_slave(ctlr)) { @@ -1108,8 +1109,11 @@ static int spi_transfer_wait(struct spi_controller *ctlr, return -EINTR; } } else { + if (!speed_hz) + speed_hz = 100000; + ms = 8LL * 1000LL * xfer->len; - do_div(ms, xfer->speed_hz); + do_div(ms, speed_hz); ms += ms + 200; /* some tolerance */
if (ms > UINT_MAX)