diff options
| -rw-r--r-- | drivers/tty/serial/8250/8250_omap.c | 7 | ||||
| -rw-r--r-- | drivers/tty/serial/omap-serial.c | 7 | ||||
| -rw-r--r-- | drivers/tty/serial/serial_core.c | 76 | ||||
| -rw-r--r-- | include/linux/serial_core.h | 21 |
4 files changed, 59 insertions, 52 deletions
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index 9191d05cfaf0..6e4ff7148ead 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -421,8 +421,11 @@ static void omap_8250_set_termios(struct uart_port *port, priv->efr = 0; up->mcr &= ~(UART_MCR_RTS | UART_MCR_XONANY); + up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF); + if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) { /* Enable AUTORTS and AUTOCTS */ + up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS; priv->efr |= UART_EFR_CTS | UART_EFR_RTS; } else if (up->port.flags & UPF_SOFT_FLOW) { /* @@ -438,8 +441,10 @@ static void omap_8250_set_termios(struct uart_port *port, * Enable XON/XOFF flow control on output. * Transmit XON1, XOFF1 */ - if (termios->c_iflag & IXOFF) + if (termios->c_iflag & IXOFF) { + up->port.status |= UPSTAT_AUTOXOFF; priv->efr |= OMAP_UART_SW_TX; + } /* * IXANY Flag: diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index b1cf9a3b673a..6129fe515932 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -1053,8 +1053,11 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios, serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG); + up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF); + if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) { /* Enable AUTORTS and AUTOCTS */ + up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS; up->efr |= UART_EFR_CTS | UART_EFR_RTS; /* Ensure MCR RTS is asserted */ @@ -1081,8 +1084,10 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios, * Enable XON/XOFF flow control on output. * Transmit XON1, XOFF1 */ - if (termios->c_iflag & IXOFF) + if (termios->c_iflag & IXOFF) { + up->port.status |= UPSTAT_AUTOXOFF; up->efr |= OMAP_UART_SW_TX; + } /* * IXANY Flag: diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 2c67a077042a..6a1055ae3437 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -179,14 +179,6 @@ static int uart_port_startup(struct tty_struct *tty, struct uart_state *state, if (tty->termios.c_cflag & CBAUD) uart_set_mctrl(uport, TIOCM_RTS | TIOCM_DTR); } - - spin_lock_irq(&uport->lock); - if (uart_cts_enabled(uport) && - !(uport->ops->get_mctrl(uport) & TIOCM_CTS)) - uport->hw_stopped = 1; - else - uport->hw_stopped = 0; - spin_unlock_irq(&uport->lock); } /* @@ -442,6 +434,7 @@ static void uart_change_speed(struct tty_struct *tty, struct uart_state *state, { struct uart_port *uport = state->uart_port; struct ktermios *termios; + int hw_stopped; /* * If we have no tty, termios, or the port does not exist, @@ -466,6 +459,18 @@ static void uart_change_speed(struct tty_struct *tty, struct uart_state *state, uport->status &= ~UPSTAT_DCD_ENABLE; else uport->status |= UPSTAT_DCD_ENABLE; + + /* reset sw-assisted CTS flow control based on (possibly) new mode */ + hw_stopped = uport->hw_stopped; + uport->hw_stopped = uart_softcts_mode(uport) && + !(uport->ops->get_mctrl(uport) & TIOCM_CTS); + if (uport->hw_stopped) { + if (!hw_stopped) + uport->ops->stop_tx(uport); + } else { + if (hw_stopped) + __uart_start(tty); + } spin_unlock_irq(&uport->lock); } @@ -619,22 +624,22 @@ static void uart_throttle(struct tty_struct *tty) { struct uart_state *state = tty->driver_data; struct uart_port *port = state->uart_port; - upf_t mask = 0; + upstat_t mask = 0; if (I_IXOFF(tty)) - mask |= UPF_SOFT_FLOW; + mask |= UPSTAT_AUTOXOFF; if (tty->termios.c_cflag & CRTSCTS) - mask |= UPF_HARD_FLOW; + mask |= UPSTAT_AUTORTS; - if (port->flags & mask) { + if (port->status & mask) { port->ops->throttle(port); - mask &= ~port->flags; + mask &= ~port->status; } - if (mask & UPF_SOFT_FLOW) + if (mask & UPSTAT_AUTOXOFF) uart_send_xchar(tty, STOP_CHAR(tty)); - if (mask & UPF_HARD_FLOW) + if (mask & UPSTAT_AUTORTS) uart_clear_mctrl(port, TIOCM_RTS); } @@ -642,22 +647,22 @@ static void uart_unthrottle(struct tty_struct *tty) { struct uart_state *state = tty->driver_data; struct uart_port *port = state->uart_port; - upf_t mask = 0; + upstat_t mask = 0; if (I_IXOFF(tty)) - mask |= UPF_SOFT_FLOW; + mask |= UPSTAT_AUTOXOFF; if (tty->termios.c_cflag & CRTSCTS) - mask |= UPF_HARD_FLOW; + mask |= UPSTAT_AUTORTS; - if (port->flags & mask) { + if (port->status & mask) { port->ops->unthrottle(port); - mask &= ~port->flags; + mask &= ~port->status; } - if (mask & UPF_SOFT_FLOW) + if (mask & UPSTAT_AUTOXOFF) uart_send_xchar(tty, START_CHAR(tty)); - if (mask & UPF_HARD_FLOW) + if (mask & UPSTAT_AUTORTS) uart_set_mctrl(port, TIOCM_RTS); } @@ -1351,30 +1356,6 @@ static void uart_set_termios(struct tty_struct *tty, mask |= TIOCM_RTS; uart_set_mctrl(uport, mask); } - - /* - * If the port is doing h/w assisted flow control, do nothing. - * We assume that port->hw_stopped has never been set. - */ - if (uport->flags & UPF_HARD_FLOW) - return; - - /* Handle turning off CRTSCTS */ - if ((old_termios->c_cflag & CRTSCTS) && !(cflag & CRTSCTS)) { - spin_lock_irq(&uport->lock); - uport->hw_stopped = 0; - __uart_start(tty); - spin_unlock_irq(&uport->lock); - } - /* Handle turning on CRTSCTS */ - else if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) { - spin_lock_irq(&uport->lock); - if (!(uport->ops->get_mctrl(uport) & TIOCM_CTS)) { - uport->hw_stopped = 1; - uport->ops->stop_tx(uport); - } - spin_unlock_irq(&uport->lock); - } } /* @@ -2855,7 +2836,7 @@ void uart_handle_cts_change(struct uart_port *uport, unsigned int status) uport->icount.cts++; - if (uart_cts_enabled(uport)) { + if (uart_softcts_mode(uport)) { if (uport->hw_stopped) { if (status) { uport->hw_stopped = 0; @@ -2868,6 +2849,7 @@ void uart_handle_cts_change(struct uart_port *uport, unsigned int status) uport->ops->stop_tx(uport); } } + } } EXPORT_SYMBOL_GPL(uart_handle_cts_change); diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index a0c7033d5f91..baf3e1d08416 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -191,8 +191,10 @@ struct uart_port { #define UPF_NO_TXEN_TEST ((__force upf_t) (1 << 15)) #define UPF_MAGIC_MULTIPLIER ((__force upf_t) ASYNC_MAGIC_MULTIPLIER /* 16 */ ) -/* Port has hardware-assisted h/w flow control (iow, auto-RTS *not* auto-CTS) */ -#define UPF_HARD_FLOW ((__force upf_t) (1 << 21)) +/* Port has hardware-assisted h/w flow control */ +#define UPF_AUTO_CTS ((__force upf_t) (1 << 20)) +#define UPF_AUTO_RTS ((__force upf_t) (1 << 21)) +#define UPF_HARD_FLOW ((__force upf_t) (UPF_AUTO_CTS | UPF_AUTO_RTS)) /* Port has hardware-assisted s/w flow control */ #define UPF_SOFT_FLOW ((__force upf_t) (1 << 22)) #define UPF_CONS_FLOW ((__force upf_t) (1 << 23)) @@ -214,11 +216,17 @@ struct uart_port { #error Change mask not equivalent to userspace-visible bit defines #endif - /* status must be updated while holding port lock */ + /* + * Must hold termios_rwsem, port mutex and port lock to change; + * can hold any one lock to read. + */ upstat_t status; #define UPSTAT_CTS_ENABLE ((__force upstat_t) (1 << 0)) #define UPSTAT_DCD_ENABLE ((__force upstat_t) (1 << 1)) +#define UPSTAT_AUTORTS ((__force upstat_t) (1 << 2)) +#define UPSTAT_AUTOCTS ((__force upstat_t) (1 << 3)) +#define UPSTAT_AUTOXOFF ((__force upstat_t) (1 << 4)) int hw_stopped; /* sw-assisted CTS flow state */ unsigned int mctrl; /* current modem ctrl settings */ @@ -392,6 +400,13 @@ static inline bool uart_cts_enabled(struct uart_port *uport) return !!(uport->status & UPSTAT_CTS_ENABLE); } +static inline bool uart_softcts_mode(struct uart_port *uport) +{ + upstat_t mask = UPSTAT_CTS_ENABLE | UPSTAT_AUTOCTS; + + return ((uport->status & mask) == UPSTAT_CTS_ENABLE); +} + /* * The following are helper functions for the low level drivers. */ |