diff options
Diffstat (limited to 'drivers/tty/serial/fsl_lpuart.c')
| -rw-r--r-- | drivers/tty/serial/fsl_lpuart.c | 84 |
1 files changed, 67 insertions, 17 deletions
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 537896c4d887..4e128d19e0ad 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -437,8 +437,8 @@ static void lpuart_dma_tx(struct lpuart_port *sport) } sport->dma_tx_desc = dmaengine_prep_slave_sg(sport->dma_tx_chan, sgl, - sport->dma_tx_nents, - DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT); + ret, DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT); if (!sport->dma_tx_desc) { dma_unmap_sg(dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE); dev_err(dev, "Cannot prepare TX slave DMA!\n"); @@ -1280,6 +1280,57 @@ static int lpuart_config_rs485(struct uart_port *port, return 0; } +static int lpuart32_config_rs485(struct uart_port *port, + struct serial_rs485 *rs485) +{ + struct lpuart_port *sport = container_of(port, + struct lpuart_port, port); + + unsigned long modem = lpuart32_read(&sport->port, UARTMODIR) + & ~(UARTMODEM_TXRTSPOL | UARTMODEM_TXRTSE); + lpuart32_write(&sport->port, modem, UARTMODIR); + + /* clear unsupported configurations */ + rs485->delay_rts_before_send = 0; + rs485->delay_rts_after_send = 0; + rs485->flags &= ~SER_RS485_RX_DURING_TX; + + if (rs485->flags & SER_RS485_ENABLED) { + /* Enable auto RS-485 RTS mode */ + modem |= UARTMODEM_TXRTSE; + + /* + * RTS needs to be logic HIGH either during transer _or_ after + * transfer, other variants are not supported by the hardware. + */ + + if (!(rs485->flags & (SER_RS485_RTS_ON_SEND | + SER_RS485_RTS_AFTER_SEND))) + rs485->flags |= SER_RS485_RTS_ON_SEND; + + if (rs485->flags & SER_RS485_RTS_ON_SEND && + rs485->flags & SER_RS485_RTS_AFTER_SEND) + rs485->flags &= ~SER_RS485_RTS_AFTER_SEND; + + /* + * The hardware defaults to RTS logic HIGH while transfer. + * Switch polarity in case RTS shall be logic HIGH + * after transfer. + * Note: UART is assumed to be active high. + */ + if (rs485->flags & SER_RS485_RTS_ON_SEND) + modem &= ~UARTMODEM_TXRTSPOL; + else if (rs485->flags & SER_RS485_RTS_AFTER_SEND) + modem |= UARTMODEM_TXRTSPOL; + } + + /* Store the new configuration */ + sport->port.rs485 = *rs485; + + lpuart32_write(&sport->port, modem, UARTMODIR); + return 0; +} + static unsigned int lpuart_get_mctrl(struct uart_port *port) { unsigned int temp = 0; @@ -1333,18 +1384,7 @@ static void lpuart_set_mctrl(struct uart_port *port, unsigned int mctrl) static void lpuart32_set_mctrl(struct uart_port *port, unsigned int mctrl) { - unsigned long temp; - - temp = lpuart32_read(port, UARTMODIR) & - ~(UARTMODIR_RXRTSE | UARTMODIR_TXCTSE); - - if (mctrl & TIOCM_RTS) - temp |= UARTMODIR_RXRTSE; - - if (mctrl & TIOCM_CTS) - temp |= UARTMODIR_TXCTSE; - lpuart32_write(port, temp, UARTMODIR); } static void lpuart_break_ctl(struct uart_port *port, int break_state) @@ -1889,11 +1929,18 @@ lpuart32_set_termios(struct uart_port *port, struct ktermios *termios, ctrl |= UARTCTRL_M; } + /* + * When auto RS-485 RTS mode is enabled, + * hardware flow control need to be disabled. + */ + if (sport->port.rs485.flags & SER_RS485_ENABLED) + termios->c_cflag &= ~CRTSCTS; + if (termios->c_cflag & CRTSCTS) { - modem |= UARTMODEM_RXRTSE | UARTMODEM_TXCTSE; + modem |= (UARTMODIR_RXRTSE | UARTMODIR_TXCTSE); } else { termios->c_cflag &= ~CRTSCTS; - modem &= ~(UARTMODEM_RXRTSE | UARTMODEM_TXCTSE); + modem &= ~(UARTMODIR_RXRTSE | UARTMODIR_TXCTSE); } if (termios->c_cflag & CSTOPB) @@ -2416,7 +2463,10 @@ static int lpuart_probe(struct platform_device *pdev) sport->port.ops = &lpuart_pops; sport->port.flags = UPF_BOOT_AUTOCONF; - sport->port.rs485_config = lpuart_config_rs485; + if (lpuart_is_32(sport)) + sport->port.rs485_config = lpuart32_config_rs485; + else + sport->port.rs485_config = lpuart_config_rs485; sport->ipg_clk = devm_clk_get(&pdev->dev, "ipg"); if (IS_ERR(sport->ipg_clk)) { @@ -2470,7 +2520,7 @@ static int lpuart_probe(struct platform_device *pdev) sport->port.rs485.delay_rts_after_send) dev_err(&pdev->dev, "driver doesn't support RTS delays\n"); - lpuart_config_rs485(&sport->port, &sport->port.rs485); + sport->port.rs485_config(&sport->port, &sport->port.rs485); sport->dma_tx_chan = dma_request_slave_channel(sport->port.dev, "tx"); if (!sport->dma_tx_chan) |