From 31f35939d1d9bcfb3099b32c67b896d2792603f9 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Fri, 2 Jan 2009 13:45:05 +0000 Subject: tty_port: Add a port level carrier detect operation This is the first step to generalising the various pieces of waiting logic duplicated in all sorts of serial drivers. Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds --- drivers/char/esp.c | 61 +++++++++++++++++++++++++++++++++--------------------- 1 file changed, 37 insertions(+), 24 deletions(-) (limited to 'drivers/char/esp.c') diff --git a/drivers/char/esp.c b/drivers/char/esp.c index 7f077c0097f6..45ec263ec012 100644 --- a/drivers/char/esp.c +++ b/drivers/char/esp.c @@ -2054,6 +2054,15 @@ static void esp_hangup(struct tty_struct *tty) wake_up_interruptible(&info->port.open_wait); } +static int esp_carrier_raised(struct tty_port *port) +{ + struct esp_struct *info = container_of(port, struct esp_struct, port); + serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT); + if (serial_in(info, UART_ESI_STAT2) & UART_MSR_DCD) + return 1; + return 0; +} + /* * ------------------------------------------------------------ * esp_open() and friends @@ -2066,17 +2075,19 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp, int retval; int do_clocal = 0; unsigned long flags; + int cd; + struct tty_port *port = &info->port; /* * If the device is in the middle of being closed, then block * until it's done, and then try again. */ if (tty_hung_up_p(filp) || - (info->port.flags & ASYNC_CLOSING)) { - if (info->port.flags & ASYNC_CLOSING) - interruptible_sleep_on(&info->port.close_wait); + (port->flags & ASYNC_CLOSING)) { + if (port->flags & ASYNC_CLOSING) + interruptible_sleep_on(&port->close_wait); #ifdef SERIAL_DO_RESTART - if (info->port.flags & ASYNC_HUP_NOTIFY) + if (port->flags & ASYNC_HUP_NOTIFY) return -EAGAIN; else return -ERESTARTSYS; @@ -2091,7 +2102,7 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp, */ if ((filp->f_flags & O_NONBLOCK) || (tty->flags & (1 << TTY_IO_ERROR))) { - info->port.flags |= ASYNC_NORMAL_ACTIVE; + port->flags |= ASYNC_NORMAL_ACTIVE; return 0; } @@ -2101,20 +2112,20 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp, /* * Block waiting for the carrier detect and the line to become * free (i.e., not in use by the callout). While we are in - * this loop, info->port.count is dropped by one, so that + * this loop, port->count is dropped by one, so that * rs_close() knows when to free things. We restore it upon * exit, either normal or abnormal. */ retval = 0; - add_wait_queue(&info->port.open_wait, &wait); + add_wait_queue(&port->open_wait, &wait); #ifdef SERIAL_DEBUG_OPEN printk(KERN_DEBUG "block_til_ready before block: ttys%d, count = %d\n", - info->line, info->port.count); + info->line, port->count); #endif spin_lock_irqsave(&info->lock, flags); if (!tty_hung_up_p(filp)) - info->port.count--; - info->port.blocked_open++; + port->count--; + port->blocked_open++; while (1) { if ((tty->termios->c_cflag & CBAUD)) { unsigned int scratch; @@ -2129,9 +2140,9 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp, } set_current_state(TASK_INTERRUPTIBLE); if (tty_hung_up_p(filp) || - !(info->port.flags & ASYNC_INITIALIZED)) { + !(port->flags & ASYNC_INITIALIZED)) { #ifdef SERIAL_DO_RESTART - if (info->port.flags & ASYNC_HUP_NOTIFY) + if (port->flags & ASYNC_HUP_NOTIFY) retval = -EAGAIN; else retval = -ERESTARTSYS; @@ -2141,11 +2152,9 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp, break; } - serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT); - if (serial_in(info, UART_ESI_STAT2) & UART_MSR_DCD) - do_clocal = 1; + cd = tty_port_carrier_raised(port); - if (!(info->port.flags & ASYNC_CLOSING) && + if (!(port->flags & ASYNC_CLOSING) && (do_clocal)) break; if (signal_pending(current)) { @@ -2154,25 +2163,25 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp, } #ifdef SERIAL_DEBUG_OPEN printk(KERN_DEBUG "block_til_ready blocking: ttys%d, count = %d\n", - info->line, info->port.count); + info->line, port->count); #endif spin_unlock_irqrestore(&info->lock, flags); schedule(); spin_lock_irqsave(&info->lock, flags); } set_current_state(TASK_RUNNING); - remove_wait_queue(&info->port.open_wait, &wait); + remove_wait_queue(&port->open_wait, &wait); if (!tty_hung_up_p(filp)) - info->port.count++; - info->port.blocked_open--; + port->count++; + port->blocked_open--; spin_unlock_irqrestore(&info->lock, flags); #ifdef SERIAL_DEBUG_OPEN printk(KERN_DEBUG "block_til_ready after blocking: ttys%d, count = %d\n", - info->line, info->port.count); + info->line, port->count); #endif if (retval) return retval; - info->port.flags |= ASYNC_NORMAL_ACTIVE; + port->flags |= ASYNC_NORMAL_ACTIVE; return 0; } @@ -2329,6 +2338,10 @@ static const struct tty_operations esp_ops = { .tiocmset = esp_tiocmset, }; +static const struct tty_port_operations esp_port_ops = { + .esp_carrier_raised, +}; + /* * The serial driver boot-time initialization code! */ @@ -2415,6 +2428,8 @@ static int __init espserial_init(void) offset = 0; do { + tty_port_init(&info->port); + info->port.ops = &esp_port_ops; info->io_port = esp[i] + offset; info->irq = irq[i]; info->line = (i * 8) + (offset / 8); @@ -2437,8 +2452,6 @@ static int __init espserial_init(void) info->config.flow_off = flow_off; info->config.pio_threshold = pio_threshold; info->next_port = ports; - init_waitqueue_head(&info->port.open_wait); - init_waitqueue_head(&info->port.close_wait); init_waitqueue_head(&info->delta_msr_wait); init_waitqueue_head(&info->break_wait); ports = info; -- cgit v1.2.3-59-g8ed1b