aboutsummaryrefslogtreecommitdiff
path: root/drivers/spi/spi-rockchip.c
diff options
context:
space:
mode:
authorGravatar Tobias Schramm <t.schramm@manjaro.org> 2021-08-27 07:03:57 +0200
committerGravatar Mark Brown <broonie@kernel.org> 2021-09-03 13:31:49 +0100
commit5457773ef99f25fcc4b238ac76b68e28273250f4 (patch)
tree903ee2f7beaf6ba441daef5d9f9664d1f6ee53b1 /drivers/spi/spi-rockchip.c
parentspi: spi-zynq-qspi: use wait_for_completion_timeout to make zynq_qspi_exec_me... (diff)
downloadlinux-5457773ef99f25fcc4b238ac76b68e28273250f4.tar.gz
linux-5457773ef99f25fcc4b238ac76b68e28273250f4.tar.bz2
linux-5457773ef99f25fcc4b238ac76b68e28273250f4.zip
spi: rockchip: handle zero length transfers without timing out
Previously zero length transfers submitted to the Rokchip SPI driver would time out in the SPI layer. This happens because the SPI peripheral does not trigger a transfer completion interrupt for zero length transfers. Fix that by completing zero length transfers immediately at start of transfer. Signed-off-by: Tobias Schramm <t.schramm@manjaro.org> Link: https://lore.kernel.org/r/20210827050357.165409-1-t.schramm@manjaro.org Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-rockchip.c')
-rw-r--r--drivers/spi/spi-rockchip.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index 540861ca2ba3..553b6b9d0222 100644
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -600,6 +600,12 @@ static int rockchip_spi_transfer_one(
int ret;
bool use_dma;
+ /* Zero length transfers won't trigger an interrupt on completion */
+ if (!xfer->len) {
+ spi_finalize_current_transfer(ctlr);
+ return 1;
+ }
+
WARN_ON(readl_relaxed(rs->regs + ROCKCHIP_SPI_SSIENR) &&
(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY));