From: Ilpo Järvinen ilpo.jarvinen@linux.intel.com
stable inclusion from stable-4.19.253 commit c44117bf20a00d377b74f67e36ebe47db1964efd category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5I4FP CVE: NA
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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@kernel.org Cc: Lukas Wunner lukas@wunner.de Reported-by: Nuno Gonçalves nunojpg@gmail.com Tested-by: Nuno Gonçalves nunojpg@gmail.com Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Link: https://lore.kernel.org/r/20220614075637.8558-1-ilpo.jarvinen@linux.intel.co... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yongqiang Liu liuyongqiang13@huawei.com --- drivers/tty/serial/amba-pl011.c | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index aae97acd183a..2ff45aae120e 100644 --- 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_port *port) 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 = @@ -1794,9 +1803,10 @@ static int pl011_allocate_irq(struct uart_amba_port *uap) */ 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); @@ -1818,7 +1828,14 @@ static void pl011_enable_interrupts(struct uart_amba_port *uap) 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) @@ -2193,6 +2210,8 @@ static const struct uart_ops amba_pl011_pops = { .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,