[04/26] serial: amba-pl010: drop low-latency workaround

Message ID 20210421095509.3024-5-johan@kernel.org
State New
Headers show
Series
  • tty: drop low-latency workarounds
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Commit Message

Johan Hovold April 21, 2021, 9:54 a.m.
Commit 2389b272168c ("[ARM] 4417/1: Serial: Fix AMBA drivers locking")
worked around the infamous low_latency behaviour of
tty_flip_buffer_push() by simply dropping and reacquiring the port lock
in the interrupt handler.

Since commit a9c3f68f3cd8 ("tty: Fix low_latency BUG"),
tty_flip_buffer_push() always schedules a work item to push data to the
line discipline and there's no need to keep any low_latency hacks around.

Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/tty/serial/amba-pl010.c | 2 --
 1 file changed, 2 deletions(-)

Patch

diff --git a/drivers/tty/serial/amba-pl010.c b/drivers/tty/serial/amba-pl010.c
index 3f96edfe569c..e744b953ca34 100644
--- a/drivers/tty/serial/amba-pl010.c
+++ b/drivers/tty/serial/amba-pl010.c
@@ -159,9 +159,7 @@  static void pl010_rx_chars(struct uart_amba_port *uap)
 	ignore_char:
 		status = readb(uap->port.membase + UART01x_FR);
 	}
-	spin_unlock(&uap->port.lock);
 	tty_flip_buffer_push(&uap->port.state->port);
-	spin_lock(&uap->port.lock);
 }
 
 static void pl010_tx_chars(struct uart_amba_port *uap)