From: Doug Brown <doug@xxxxxxxxxxxxx>
commit c5603e2a621dac10c5e21cc430848ebcfa6c7e01 upstream.
This reverts commit 7bfb915a597a301abb892f620fe5c283a9fdbd77.
This commit broke pxa and omap-serial, because it inhibited them from
calling stop_tx() if their TX FIFOs weren't completely empty. This
resulted in these two drivers hanging during transmits because the TX
interrupt would stay enabled, and a new TX interrupt would never fire.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 7bfb915a597a ("serial: core: only stop transmit when HW fifo is empty")
Signed-off-by: Doug Brown <doug@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20240606195632.173255-2-doug@xxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
include/linux/serial_core.h | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -787,8 +787,7 @@ enum UART_TX_FLAGS {
if (pending < WAKEUP_CHARS) { \
uart_write_wakeup(__port); \
\
- if (!((flags) & UART_TX_NOSTOP) && pending == 0 && \
- __port->ops->tx_empty(__port)) \
+ if (!((flags) & UART_TX_NOSTOP) && pending == 0) \
__port->ops->stop_tx(__port); \
} \
\
Patches currently in stable-queue which might be from doug@xxxxxxxxxxxxx are
queue-6.6/revert-serial-core-only-stop-transmit-when-hw-fifo-is-empty.patch
queue-6.6/serial-bcm63xx-uart-fix-tx-after-conversion-to-uart_port_tx_limited.patch
queue-6.6/serial-core-introduce-uart_port_tx_limited_flags.patch
