Define local variables holding information about whether pdc or dma is used in the HW. These are retested several times by calls to atmel_use_pdc_tx() and atmel_use_dma_tx(). So to make the code more readable, simply cache the values. This is also a preparatory patch for the next one (where is_pdc is used once more in atmel_stop_tx()). Cc: Richard Genoud <richard.genoud@xxxxxxxxx> Cc: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx> Cc: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx> Cc: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Reported-by: Michael Walle <michael@xxxxxxxx> Signed-off-by: Jiri Slaby (SUSE) <jirislaby@xxxxxxxxxx> --- drivers/tty/serial/atmel_serial.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 4ca04676c406..65f63dccfd72 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -552,8 +552,9 @@ static u_int atmel_get_mctrl(struct uart_port *port) static void atmel_stop_tx(struct uart_port *port) { struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + bool is_pdc = atmel_use_pdc_tx(port); - if (atmel_use_pdc_tx(port)) { + if (is_pdc) { /* disable PDC transmit */ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS); } @@ -572,7 +573,6 @@ static void atmel_stop_tx(struct uart_port *port) if (atmel_uart_is_half_duplex(port)) if (!atomic_read(&atmel_port->tasklet_shutdown)) atmel_start_rx(port); - } /* @@ -581,20 +581,22 @@ static void atmel_stop_tx(struct uart_port *port) static void atmel_start_tx(struct uart_port *port) { struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + bool is_pdc = atmel_use_pdc_tx(port); + bool is_dma = is_pdc || atmel_use_dma_tx(port); - if (atmel_use_pdc_tx(port) && (atmel_uart_readl(port, ATMEL_PDC_PTSR) + if (is_pdc && (atmel_uart_readl(port, ATMEL_PDC_PTSR) & ATMEL_PDC_TXTEN)) /* The transmitter is already running. Yes, we really need this.*/ return; - if (atmel_use_pdc_tx(port) || atmel_use_dma_tx(port)) - if (atmel_uart_is_half_duplex(port)) - atmel_stop_rx(port); + if (is_dma && atmel_uart_is_half_duplex(port)) + atmel_stop_rx(port); - if (atmel_use_pdc_tx(port)) + if (is_pdc) { /* re-enable PDC transmit */ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN); + } /* Enable interrupts */ atmel_uart_writel(port, ATMEL_US_IER, atmel_port->tx_done_mask); -- 2.38.1