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,
