mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-22 15:02:32 +00:00
62 lines
1.9 KiB
Diff
62 lines
1.9 KiB
Diff
|
From 3cec61f1b19a6f589f8b2aef97977e1c38eb7b70 Mon Sep 17 00:00:00 2001
|
||
|
|
From: Phil Elwell <phil@raspberrypi.org>
|
||
|
|
Date: Fri, 24 Jan 2020 11:38:28 +0000
|
||
|
|
Subject: [PATCH] tty: amba-pl011: Add un/throttle support
|
||
|
|
|
||
|
|
The PL011 driver lacks throttle and unthrottle methods. As a result,
|
||
|
|
sending more data to the Pi than it can immediately sink while CRTSCTS
|
||
|
|
is enabled causes a NULL pointer to be followed.
|
||
|
|
|
||
|
|
Add a throttle handler that disables the RX interrupts, and an
|
||
|
|
unthrottle handler that reenables them.
|
||
|
|
|
||
|
|
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
|
||
|
|
---
|
||
|
|
drivers/tty/serial/amba-pl011.c | 28 ++++++++++++++++++++++++++++
|
||
|
|
1 file changed, 28 insertions(+)
|
||
|
|
|
||
|
|
--- a/drivers/tty/serial/amba-pl011.c
|
||
|
|
+++ b/drivers/tty/serial/amba-pl011.c
|
||
|
|
@@ -1317,6 +1317,32 @@ static void pl011_start_tx(struct uart_p
|
||
|
|
pl011_start_tx_pio(uap);
|
||
|
|
}
|
||
|
|
|
||
|
|
+static void pl011_throttle(struct uart_port *port)
|
||
|
|
+{
|
||
|
|
+ struct uart_amba_port *uap =
|
||
|
|
+ container_of(port, struct uart_amba_port, port);
|
||
|
|
+ unsigned long flags;
|
||
|
|
+
|
||
|
|
+ spin_lock_irqsave(&uap->port.lock, flags);
|
||
|
|
+ uap->im &= ~(UART011_RTIM | UART011_RXIM);
|
||
|
|
+ pl011_write(uap->im, uap, REG_IMSC);
|
||
|
|
+ spin_unlock_irqrestore(&uap->port.lock, flags);
|
||
|
|
+}
|
||
|
|
+
|
||
|
|
+static void pl011_unthrottle(struct uart_port *port)
|
||
|
|
+{
|
||
|
|
+ struct uart_amba_port *uap =
|
||
|
|
+ container_of(port, struct uart_amba_port, port);
|
||
|
|
+ unsigned long flags;
|
||
|
|
+
|
||
|
|
+ spin_lock_irqsave(&uap->port.lock, flags);
|
||
|
|
+ uap->im |= UART011_RTIM;
|
||
|
|
+ if (!pl011_dma_rx_running(uap))
|
||
|
|
+ uap->im |= UART011_RXIM;
|
||
|
|
+ pl011_write(uap->im, uap, REG_IMSC);
|
||
|
|
+ spin_unlock_irqrestore(&uap->port.lock, flags);
|
||
|
|
+}
|
||
|
|
+
|
||
|
|
static void pl011_stop_rx(struct uart_port *port)
|
||
|
|
{
|
||
|
|
struct uart_amba_port *uap =
|
||
|
|
@@ -2156,6 +2182,8 @@ 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,
|
||
|
|
+ .unthrottle = pl011_unthrottle,
|
||
|
|
.enable_ms = pl011_enable_ms,
|
||
|
|
.break_ctl = pl011_break_ctl,
|
||
|
|
.startup = pl011_startup,
|