diff options
Diffstat (limited to 'drivers/tty/serial/amba-pl011.c')
-rw-r--r-- | drivers/tty/serial/amba-pl011.c | 23 |
1 files changed, 14 insertions, 9 deletions
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index b0a377725d63..37257badcb97 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -1327,14 +1327,15 @@ static void pl011_stop_tx(struct uart_port *port) pl011_dma_tx_stop(uap); } -static void pl011_tx_chars(struct uart_amba_port *uap, bool from_irq); +static bool pl011_tx_chars(struct uart_amba_port *uap, bool from_irq); /* Start TX with programmed I/O only (no DMA) */ static void pl011_start_tx_pio(struct uart_amba_port *uap) { - uap->im |= UART011_TXIM; - pl011_write(uap->im, uap, REG_IMSC); - pl011_tx_chars(uap, false); + if (pl011_tx_chars(uap, false)) { + uap->im |= UART011_TXIM; + pl011_write(uap->im, uap, REG_IMSC); + } } static void pl011_start_tx(struct uart_port *port) @@ -1414,25 +1415,26 @@ static bool pl011_tx_char(struct uart_amba_port *uap, unsigned char c, return true; } -static void pl011_tx_chars(struct uart_amba_port *uap, bool from_irq) +/* Returns true if tx interrupts have to be (kept) enabled */ +static bool pl011_tx_chars(struct uart_amba_port *uap, bool from_irq) { struct circ_buf *xmit = &uap->port.state->xmit; int count = uap->fifosize >> 1; if (uap->port.x_char) { if (!pl011_tx_char(uap, uap->port.x_char, from_irq)) - return; + return true; uap->port.x_char = 0; --count; } if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) { pl011_stop_tx(&uap->port); - return; + return false; } /* If we are using DMA mode, try to send some characters. */ if (pl011_dma_tx_irq(uap)) - return; + return true; do { if (likely(from_irq) && count-- == 0) @@ -1447,8 +1449,11 @@ static void pl011_tx_chars(struct uart_amba_port *uap, bool from_irq) if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) uart_write_wakeup(&uap->port); - if (uart_circ_empty(xmit)) + if (uart_circ_empty(xmit)) { pl011_stop_tx(&uap->port); + return false; + } + return true; } static void pl011_modem_status(struct uart_amba_port *uap) |