diff options
Diffstat (limited to 'drivers/tty/serial/atmel_serial.c')
| -rw-r--r-- | drivers/tty/serial/atmel_serial.c | 73 |
1 files changed, 64 insertions, 9 deletions
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 168b10cad47b..dcebb28ffbc4 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -175,6 +175,17 @@ struct atmel_uart_port { unsigned int pending_status; spinlock_t lock_suspended; + struct { + u32 cr; + u32 mr; + u32 imr; + u32 brgr; + u32 rtor; + u32 ttgr; + u32 fmr; + u32 fimr; + } cache; + int (*prepare_rx)(struct uart_port *port); int (*prepare_tx)(struct uart_port *port); void (*schedule_rx)(struct uart_port *port); @@ -481,6 +492,14 @@ static void atmel_stop_tx(struct uart_port *port) /* disable PDC transmit */ atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS); } + + /* + * Disable the transmitter. + * This is mandatory when DMA is used, otherwise the DMA buffer + * is fully transmitted. + */ + atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXDIS); + /* Disable interrupts */ atmel_uart_writel(port, ATMEL_US_IDR, atmel_port->tx_done_mask); @@ -513,6 +532,9 @@ static void atmel_start_tx(struct uart_port *port) /* Enable interrupts */ atmel_uart_writel(port, ATMEL_US_IER, atmel_port->tx_done_mask); + + /* re-enable the transmitter */ + atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN); } /* @@ -798,6 +820,11 @@ static void atmel_complete_tx_dma(void *arg) */ if (!uart_circ_empty(xmit)) atmel_tasklet_schedule(atmel_port, &atmel_port->tasklet_tx); + else if ((port->rs485.flags & SER_RS485_ENABLED) && + !(port->rs485.flags & SER_RS485_RX_DURING_TX)) { + /* DMA done, stop TX, start RX for RS485 */ + atmel_start_rx(port); + } spin_unlock_irqrestore(&port->lock, flags); } @@ -900,12 +927,6 @@ static void atmel_tx_dma(struct uart_port *port) desc->callback = atmel_complete_tx_dma; desc->callback_param = atmel_port; atmel_port->cookie_tx = dmaengine_submit(desc); - - } else { - if (port->rs485.flags & SER_RS485_ENABLED) { - /* DMA done, stop TX, start RX for RS485 */ - atmel_start_rx(port); - } } if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) @@ -1748,7 +1769,9 @@ static void atmel_get_ip_name(struct uart_port *port) /* * Only USART devices from at91sam9260 SOC implement fractional - * baudrate. + * baudrate. It is available for all asynchronous modes, with the + * following restriction: the sampling clock's duty cycle is not + * constant. */ atmel_port->has_frac_baudrate = false; atmel_port->has_hw_timer = false; @@ -2192,8 +2215,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, * then * 8 CD + FP = selected clock / (2 * baudrate) */ - if (atmel_port->has_frac_baudrate && - (mode & ATMEL_US_USMODE) == ATMEL_US_USMODE_NORMAL) { + if (atmel_port->has_frac_baudrate) { div = DIV_ROUND_CLOSEST(port->uartclk, baud * 2); cd = div >> 3; fp = div & ATMEL_US_FP_MASK; @@ -2649,6 +2671,20 @@ static int atmel_serial_suspend(struct platform_device *pdev, cpu_relax(); } + if (atmel_is_console_port(port) && !console_suspend_enabled) { + /* Cache register values as we won't get a full shutdown/startup + * cycle + */ + atmel_port->cache.mr = atmel_uart_readl(port, ATMEL_US_MR); + atmel_port->cache.imr = atmel_uart_readl(port, ATMEL_US_IMR); + atmel_port->cache.brgr = atmel_uart_readl(port, ATMEL_US_BRGR); + atmel_port->cache.rtor = atmel_uart_readl(port, + atmel_port->rtor); + atmel_port->cache.ttgr = atmel_uart_readl(port, ATMEL_US_TTGR); + atmel_port->cache.fmr = atmel_uart_readl(port, ATMEL_US_FMR); + atmel_port->cache.fimr = atmel_uart_readl(port, ATMEL_US_FIMR); + } + /* we can not wake up if we're running on slow clock */ atmel_port->may_wakeup = device_may_wakeup(&pdev->dev); if (atmel_serial_clk_will_stop()) { @@ -2671,6 +2707,25 @@ static int atmel_serial_resume(struct platform_device *pdev) struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); unsigned long flags; + if (atmel_is_console_port(port) && !console_suspend_enabled) { + atmel_uart_writel(port, ATMEL_US_MR, atmel_port->cache.mr); + atmel_uart_writel(port, ATMEL_US_IER, atmel_port->cache.imr); + atmel_uart_writel(port, ATMEL_US_BRGR, atmel_port->cache.brgr); + atmel_uart_writel(port, atmel_port->rtor, + atmel_port->cache.rtor); + atmel_uart_writel(port, ATMEL_US_TTGR, atmel_port->cache.ttgr); + + if (atmel_port->fifo_size) { + atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_FIFOEN | + ATMEL_US_RXFCLR | ATMEL_US_TXFLCLR); + atmel_uart_writel(port, ATMEL_US_FMR, + atmel_port->cache.fmr); + atmel_uart_writel(port, ATMEL_US_FIER, + atmel_port->cache.fimr); + } + atmel_start_rx(port); + } + spin_lock_irqsave(&atmel_port->lock_suspended, flags); if (atmel_port->pending) { atmel_handle_receive(port, atmel_port->pending); |