This is a note to let you know that I've just added the patch titled
serial: pl011: UPSTAT_AUTORTS requires .throttle/unthrottle
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
serial-pl011-upstat_autorts-requires-.throttle-unthrottle.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 211565b100993c90b53bf40851eacaefc830cfe0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Date: Tue, 14 Jun 2022 10:56:37 +0300
Subject: serial: pl011: UPSTAT_AUTORTS requires .throttle/unthrottle
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From: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
commit 211565b100993c90b53bf40851eacaefc830cfe0 upstream.
The driver must provide throttle and unthrottle in uart_ops when it
sets UPSTAT_AUTORTS. Add them using existing stop_rx &
enable_interrupts functions.
Fixes: 2a76fa283098 (serial: pl011: Adopt generic flag to store auto RTS status)
Cc: stable <stable@xxxxxxxxxx>
Cc: Lukas Wunner <lukas@xxxxxxxxx>
Reported-by: Nuno Gonçalves <nunojpg@xxxxxxxxx>
Tested-by: Nuno Gonçalves <nunojpg@xxxxxxxxx>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20220614075637.8558-1-ilpo.jarvinen@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/tty/serial/amba-pl011.c | 23 +++++++++++++++++++++--
1 file changed, 21 insertions(+), 2 deletions(-)
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -1335,6 +1335,15 @@ static void pl011_stop_rx(struct uart_po
pl011_dma_rx_stop(uap);
}
+static void pl011_throttle_rx(struct uart_port *port)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&port->lock, flags);
+ pl011_stop_rx(port);
+ spin_unlock_irqrestore(&port->lock, flags);
+}
+
static void pl011_enable_ms(struct uart_port *port)
{
struct uart_amba_port *uap =
@@ -1728,9 +1737,10 @@ static int pl011_allocate_irq(struct uar
*/
static void pl011_enable_interrupts(struct uart_amba_port *uap)
{
+ unsigned long flags;
unsigned int i;
- spin_lock_irq(&uap->port.lock);
+ spin_lock_irqsave(&uap->port.lock, flags);
/* Clear out any spuriously appearing RX interrupts */
pl011_write(UART011_RTIS | UART011_RXIS, uap, REG_ICR);
@@ -1752,7 +1762,14 @@ static void pl011_enable_interrupts(stru
if (!pl011_dma_rx_running(uap))
uap->im |= UART011_RXIM;
pl011_write(uap->im, uap, REG_IMSC);
- spin_unlock_irq(&uap->port.lock);
+ spin_unlock_irqrestore(&uap->port.lock, flags);
+}
+
+static void pl011_unthrottle_rx(struct uart_port *port)
+{
+ struct uart_amba_port *uap = container_of(port, struct uart_amba_port, port);
+
+ pl011_enable_interrupts(uap);
}
static int pl011_startup(struct uart_port *port)
@@ -2127,6 +2144,8 @@ static const struct uart_ops amba_pl011_
.stop_tx = pl011_stop_tx,
.start_tx = pl011_start_tx,
.stop_rx = pl011_stop_rx,
+ .throttle = pl011_throttle_rx,
+ .unthrottle = pl011_unthrottle_rx,
.enable_ms = pl011_enable_ms,
.break_ctl = pl011_break_ctl,
.startup = pl011_startup,
Patches currently in stable-queue which might be from ilpo.jarvinen@xxxxxxxxxxxxxxx are
queue-5.4/serial-pl011-upstat_autorts-requires-.throttle-unthrottle.patch
queue-5.4/serial-stm32-clear-prev-values-before-setting-rts-delays.patch
