1 files changed, 199 insertions, 104 deletions

diff --git a/drivers/mmc/card/sdio_uart.c b/drivers/mmc/card/sdio_uart.c
index b8e7c5ae981e..f53755533e7e 100644
--- a/drivers/mmc/card/sdio_uart.c
+++ b/drivers/mmc/card/sdio_uart.c
@@ -29,6 +29,7 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
+#include <linux/sched.h>
 #include <linux/mutex.h>
 #include <linux/seq_file.h>
 #include <linux/serial_reg.h>
@@ -73,11 +74,10 @@ struct uart_icount {
 };
 
 struct sdio_uart_port {
+	struct tty_port		port;
 	struct kref		kref;
 	struct tty_struct	*tty;
 	unsigned int		index;
-	unsigned int		opened;
-	struct mutex		open_lock;
 	struct sdio_func	*func;
 	struct mutex		func_lock;
 	struct task_struct	*in_sdio_uart_irq;
@@ -87,6 +87,7 @@ struct sdio_uart_port {
 	struct uart_icount	icount;
 	unsigned int		uartclk;
 	unsigned int		mctrl;
+	unsigned int		rx_mctrl;
 	unsigned int		read_status_mask;
 	unsigned int		ignore_status_mask;
 	unsigned char		x_char;
@@ -102,7 +103,6 @@ static int sdio_uart_add_port(struct sdio_uart_port *port)
 	int index, ret = -EBUSY;
 
 	kref_init(&port->kref);
-	mutex_init(&port->open_lock);
 	mutex_init(&port->func_lock);
 	spin_lock_init(&port->write_lock);
 
@@ -151,6 +151,7 @@ static void sdio_uart_port_put(struct sdio_uart_port *port)
 static void sdio_uart_port_remove(struct sdio_uart_port *port)
 {
 	struct sdio_func *func;
+	struct tty_struct *tty;
 
 	BUG_ON(sdio_uart_table[port->index] != port);
 
@@ -165,15 +166,19 @@ static void sdio_uart_port_remove(struct sdio_uart_port *port)
 	 * give up on that port ASAP.
 	 * Beware: the lock ordering is critical.
 	 */
-	mutex_lock(&port->open_lock);
+	mutex_lock(&port->port.mutex);
 	mutex_lock(&port->func_lock);
 	func = port->func;
 	sdio_claim_host(func);
 	port->func = NULL;
 	mutex_unlock(&port->func_lock);
-	if (port->opened)
-		tty_hangup(port->tty);
-	mutex_unlock(&port->open_lock);
+	tty = tty_port_tty_get(&port->port);
+	/* tty_hangup is async so is this safe as is ?? */
+	if (tty) {
+		tty_hangup(tty);
+		tty_kref_put(tty);
+	}
+	mutex_unlock(&port->port.mutex);
 	sdio_release_irq(func);
 	sdio_disable_func(func);
 	sdio_release_host(func);
@@ -217,6 +222,8 @@ static unsigned int sdio_uart_get_mctrl(struct sdio_uart_port *port)
 	unsigned char status;
 	unsigned int ret;
 
+	/* FIXME: What stops this losing the delta bits and breaking
+	   sdio_uart_check_modem_status ? */
 	status = sdio_in(port, UART_MSR);
 
 	ret = 0;
@@ -391,7 +398,7 @@ static void sdio_uart_stop_rx(struct sdio_uart_port *port)
 static void sdio_uart_receive_chars(struct sdio_uart_port *port,
 				    unsigned int *status)
 {
-	struct tty_struct *tty = port->tty;
+	struct tty_struct *tty = tty_port_tty_get(&port->port);
 	unsigned int ch, flag;
 	int max_count = 256;
 
@@ -428,24 +435,30 @@ static void sdio_uart_receive_chars(struct sdio_uart_port *port,
 		}
 
 		if ((*status & port->ignore_status_mask & ~UART_LSR_OE) == 0)
-			tty_insert_flip_char(tty, ch, flag);
+			if (tty)
+				tty_insert_flip_char(tty, ch, flag);
 
 		/*
 		 * Overrun is special.  Since it's reported immediately,
 		 * it doesn't affect the current character.
 		 */
 		if (*status & ~port->ignore_status_mask & UART_LSR_OE)
-			tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+			if (tty)
+				tty_insert_flip_char(tty, 0, TTY_OVERRUN);
 
 		*status = sdio_in(port, UART_LSR);
 	} while ((*status & UART_LSR_DR) && (max_count-- > 0));
-	tty_flip_buffer_push(tty);
+	if (tty) {
+		tty_flip_buffer_push(tty);
+		tty_kref_put(tty);
+	}
 }
 
 static void sdio_uart_transmit_chars(struct sdio_uart_port *port)
 {
 	struct circ_buf *xmit = &port->xmit;
 	int count;
+	struct tty_struct *tty;
 
 	if (port->x_char) {
 		sdio_out(port, UART_TX, port->x_char);
@@ -453,8 +466,13 @@ static void sdio_uart_transmit_chars(struct sdio_uart_port *port)
 		port->x_char = 0;
 		return;
 	}
-	if (circ_empty(xmit) || port->tty->stopped || port->tty->hw_stopped) {
+
+	tty = tty_port_tty_get(&port->port);
+
+	if (tty == NULL || circ_empty(xmit) ||
+				tty->stopped || tty->hw_stopped) {
 		sdio_uart_stop_tx(port);
+		tty_kref_put(tty);
 		return;
 	}
 
@@ -468,15 +486,17 @@ static void sdio_uart_transmit_chars(struct sdio_uart_port *port)
 	} while (--count > 0);
 
 	if (circ_chars_pending(xmit) < WAKEUP_CHARS)
-		tty_wakeup(port->tty);
+		tty_wakeup(tty);
 
 	if (circ_empty(xmit))
 		sdio_uart_stop_tx(port);
+	tty_kref_put(tty);
 }
 
 static void sdio_uart_check_modem_status(struct sdio_uart_port *port)
 {
 	int status;
+	struct tty_struct *tty;
 
 	status = sdio_in(port, UART_MSR);
 
@@ -487,25 +507,39 @@ static void sdio_uart_check_modem_status(struct sdio_uart_port *port)
 		port->icount.rng++;
 	if (status & UART_MSR_DDSR)
 		port->icount.dsr++;
-	if (status & UART_MSR_DDCD)
+	if (status & UART_MSR_DDCD) {
 		port->icount.dcd++;
+		/* DCD raise - wake for open */
+		if (status & UART_MSR_DCD)
+			wake_up_interruptible(&port->port.open_wait);
+		else {
+			/* DCD drop - hang up if tty attached */
+			tty = tty_port_tty_get(&port->port);
+			if (tty) {
+				tty_hangup(tty);
+				tty_kref_put(tty);
+			}
+		}
+	}
 	if (status & UART_MSR_DCTS) {
 		port->icount.cts++;
-		if (port->tty->termios->c_cflag & CRTSCTS) {
+		tty = tty_port_tty_get(&port->port);
+		if (tty && (tty->termios->c_cflag & CRTSCTS)) {
 			int cts = (status & UART_MSR_CTS);
-			if (port->tty->hw_stopped) {
+			if (tty->hw_stopped) {
 				if (cts) {
-					port->tty->hw_stopped = 0;
+					tty->hw_stopped = 0;
 					sdio_uart_start_tx(port);
-					tty_wakeup(port->tty);
+					tty_wakeup(tty);
 				}
 			} else {
 				if (!cts) {
-					port->tty->hw_stopped = 1;
+					tty->hw_stopped = 1;
 					sdio_uart_stop_tx(port);
 				}
 			}
 		}
+		tty_kref_put(tty);
 	}
 }
 
@@ -542,8 +576,62 @@ static void sdio_uart_irq(struct sdio_func *func)
 	port->in_sdio_uart_irq = NULL;
 }
 
-static int sdio_uart_startup(struct sdio_uart_port *port)
+static int uart_carrier_raised(struct tty_port *tport)
+{
+	struct sdio_uart_port *port =
+			container_of(tport, struct sdio_uart_port, port);
+	unsigned int ret = sdio_uart_claim_func(port);
+	if (ret)	/* Missing hardware shoudn't block for carrier */
+		return 1;
+	ret = sdio_uart_get_mctrl(port);
+	sdio_uart_release_func(port);
+	if (ret & TIOCM_CAR)
+		return 1;
+	return 0;
+}
+
+/**
+ *	uart_dtr_rts		-	 port helper to set uart signals
+ *	@tport: tty port to be updated
+ *	@onoff: set to turn on DTR/RTS
+ *
+ *	Called by the tty port helpers when the modem signals need to be
+ *	adjusted during an open, close and hangup.
+ */
+
+static void uart_dtr_rts(struct tty_port *tport, int onoff)
+{
+	struct sdio_uart_port *port =
+			container_of(tport, struct sdio_uart_port, port);
+	int ret = sdio_uart_claim_func(port);
+	if (ret)
+		return;
+	if (onoff == 0)
+		sdio_uart_clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
+	else
+		sdio_uart_set_mctrl(port, TIOCM_DTR | TIOCM_RTS);
+	sdio_uart_release_func(port);
+}
+
+/**
+ *	sdio_uart_activate	-	start up hardware
+ *	@tport: tty port to activate
+ *	@tty: tty bound to this port
+ *
+ *	Activate a tty port. The port locking guarantees us this will be
+ *	run exactly once per set of opens, and if successful will see the
+ *	shutdown method run exactly once to match. Start up and shutdown are
+ *	protected from each other by the internal locking and will not run
+ *	at the same time even during a hangup event.
+ *
+ *	If we successfully start up the port we take an extra kref as we
+ *	will keep it around until shutdown when the kref is dropped.
+ */
+
+static int sdio_uart_activate(struct tty_port *tport, struct tty_struct *tty)
 {
+	struct sdio_uart_port *port =
+			container_of(tport, struct sdio_uart_port, port);
 	unsigned long page;
 	int ret;
 
@@ -551,7 +639,7 @@ static int sdio_uart_startup(struct sdio_uart_port *port)
 	 * Set the TTY IO error marker - we will only clear this
 	 * once we have successfully opened the port.
 	 */
-	set_bit(TTY_IO_ERROR, &port->tty->flags);
+	set_bit(TTY_IO_ERROR, &tty->flags);
 
 	/* Initialise and allocate the transmit buffer. */
 	page = __get_free_page(GFP_KERNEL);
@@ -592,19 +680,19 @@ static int sdio_uart_startup(struct sdio_uart_port *port)
 	 */
 	sdio_out(port, UART_LCR, UART_LCR_WLEN8);
 
-	port->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE | UART_IER_UUE;
+	port->ier = UART_IER_RLSI|UART_IER_RDI|UART_IER_RTOIE|UART_IER_UUE;
 	port->mctrl = TIOCM_OUT2;
 
-	sdio_uart_change_speed(port, port->tty->termios, NULL);
+	sdio_uart_change_speed(port, tty->termios, NULL);
 
-	if (port->tty->termios->c_cflag & CBAUD)
+	if (tty->termios->c_cflag & CBAUD)
 		sdio_uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR);
 
-	if (port->tty->termios->c_cflag & CRTSCTS)
+	if (tty->termios->c_cflag & CRTSCTS)
 		if (!(sdio_uart_get_mctrl(port) & TIOCM_CTS))
-			port->tty->hw_stopped = 1;
+			tty->hw_stopped = 1;
 
-	clear_bit(TTY_IO_ERROR, &port->tty->flags);
+	clear_bit(TTY_IO_ERROR, &tty->flags);
 
 	/* Kick the IRQ handler once while we're still holding the host lock */
 	sdio_uart_irq(port->func);
@@ -621,8 +709,20 @@ err1:
 	return ret;
 }
 
-static void sdio_uart_shutdown(struct sdio_uart_port *port)
+/**
+ *	sdio_uart_shutdown	-	stop hardware
+ *	@tport: tty port to shut down
+ *
+ *	Deactivate a tty port. The port locking guarantees us this will be
+ *	run only if a successful matching activate already ran. The two are
+ *	protected from each other by the internal locking and will not run
+ *	at the same time even during a hangup event.
+ */
+
+static void sdio_uart_shutdown(struct tty_port *tport)
 {
+	struct sdio_uart_port *port =
+			container_of(tport, struct sdio_uart_port, port);
 	int ret;
 
 	ret = sdio_uart_claim_func(port);
@@ -631,12 +731,6 @@ static void sdio_uart_shutdown(struct sdio_uart_port *port)
 
 	sdio_uart_stop_rx(port);
 
-	/* TODO: wait here for TX FIFO to drain */
-
-	/* Turn off DTR and RTS early. */
-	if (port->tty->termios->c_cflag & HUPCL)
-		sdio_uart_clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
-
 	/* Disable interrupts from this port */
 	sdio_release_irq(port->func);
 	port->ier = 0;
@@ -661,77 +755,70 @@ skip:
 	free_page((unsigned long)port->xmit.buf);
 }
 
-static int sdio_uart_open(struct tty_struct *tty, struct file *filp)
+/**
+ *	sdio_uart_install	-	install method
+ *	@driver: the driver in use (sdio_uart in our case)
+ *	@tty: the tty being bound
+ *
+ *	Look up and bind the tty and the driver together. Initialize
+ *	any needed private data (in our case the termios)
+ */
+
+static int sdio_uart_install(struct tty_driver *driver, struct tty_struct *tty)
 {
-	struct sdio_uart_port *port;
-	int ret;
+	int idx = tty->index;
+	struct sdio_uart_port *port = sdio_uart_port_get(idx);
+	int ret = tty_init_termios(tty);
+
+	if (ret == 0) {
+		tty_driver_kref_get(driver);
+		tty->count++;
+		/* This is the ref sdio_uart_port get provided */
+		tty->driver_data = port;
+		driver->ttys[idx] = tty;
+	} else
+		sdio_uart_port_put(port);
+	return ret;
+}
 
-	port = sdio_uart_port_get(tty->index);
-	if (!port)
-		return -ENODEV;
+/**
+ *	sdio_uart_cleanup	-	called on the last tty kref drop
+ *	@tty: the tty being destroyed
+ *
+ *	Called asynchronously when the last reference to the tty is dropped.
+ *	We cannot destroy the tty->driver_data port kref until this point
+ */
 
-	mutex_lock(&port->open_lock);
+static void sdio_uart_cleanup(struct tty_struct *tty)
+{
+	struct sdio_uart_port *port = tty->driver_data;
+	tty->driver_data = NULL;	/* Bug trap */
+	sdio_uart_port_put(port);
+}
 
-	/*
-	 * Make sure not to mess up with a dead port
-	 * which has not been closed yet.
-	 */
-	if (tty->driver_data && tty->driver_data != port) {
-		mutex_unlock(&port->open_lock);
-		sdio_uart_port_put(port);
-		return -EBUSY;
-	}
+/*
+ *	Open/close/hangup is now entirely boilerplate
+ */
 
-	if (!port->opened) {
-		tty->driver_data = port;
-		port->tty = tty;
-		ret = sdio_uart_startup(port);
-		if (ret) {
-			tty->driver_data = NULL;
-			port->tty = NULL;
-			mutex_unlock(&port->open_lock);
-			sdio_uart_port_put(port);
-			return ret;
-		}
-	}
-	port->opened++;
-	mutex_unlock(&port->open_lock);
-	return 0;
+static int sdio_uart_open(struct tty_struct *tty, struct file *filp)
+{
+	struct sdio_uart_port *port = tty->driver_data;
+	return tty_port_open(&port->port, tty, filp);
 }
 
 static void sdio_uart_close(struct tty_struct *tty, struct file * filp)
 {
 	struct sdio_uart_port *port = tty->driver_data;
+	tty_port_close(&port->port, tty, filp);
+}
 
-	if (!port)
-		return;
-
-	mutex_lock(&port->open_lock);
-	BUG_ON(!port->opened);
-
-	/*
-	 * This is messy.  The tty layer calls us even when open()
-	 * returned an error.  Ignore this close request if tty->count
-	 * is larger than port->count.
-	 */
-	if (tty->count > port->opened) {
-		mutex_unlock(&port->open_lock);
-		return;
-	}
-
-	if (--port->opened == 0) {
-		tty->closing = 1;
-		sdio_uart_shutdown(port);
-		tty_ldisc_flush(tty);
-		port->tty = NULL;
-		tty->driver_data = NULL;
-		tty->closing = 0;
-	}
-	mutex_unlock(&port->open_lock);
-	sdio_uart_port_put(port);
+static void sdio_uart_hangup(struct tty_struct *tty)
+{
+	struct sdio_uart_port *port = tty->driver_data;
+	tty_port_hangup(&port->port);
 }
 
-static int sdio_uart_write(struct tty_struct * tty, const unsigned char *buf,
+static int sdio_uart_write(struct tty_struct *tty, const unsigned char *buf,
 			   int count)
 {
 	struct sdio_uart_port *port = tty->driver_data;
@@ -756,7 +843,7 @@ static int sdio_uart_write(struct tty_struct * tty, const unsigned char *buf,
 	}
 	spin_unlock(&port->write_lock);
 
-	if ( !(port->ier & UART_IER_THRI)) {
+	if (!(port->ier & UART_IER_THRI)) {
 		int err = sdio_uart_claim_func(port);
 		if (!err) {
 			sdio_uart_start_tx(port);
@@ -843,17 +930,12 @@ static void sdio_uart_unthrottle(struct tty_struct *tty)
 	sdio_uart_release_func(port);
 }
 
-static void sdio_uart_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
+static void sdio_uart_set_termios(struct tty_struct *tty,
+						struct ktermios *old_termios)
 {
 	struct sdio_uart_port *port = tty->driver_data;
 	unsigned int cflag = tty->termios->c_cflag;
 
-#define RELEVANT_IFLAG(iflag)	((iflag) & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
-
-	if ((cflag ^ old_termios->c_cflag) == 0 &&
-	    RELEVANT_IFLAG(tty->termios->c_iflag ^ old_termios->c_iflag) == 0)
-		return;
-
 	if (sdio_uart_claim_func(port) != 0)
 		return;
 
@@ -928,7 +1010,7 @@ static int sdio_uart_tiocmset(struct tty_struct *tty, struct file *file,
 	int result;
 
 	result = sdio_uart_claim_func(port);
-	if(!result) {
+	if (!result) {
 		sdio_uart_update_mctrl(port, set, clear);
 		sdio_uart_release_func(port);
 	}
@@ -946,7 +1028,7 @@ static int sdio_uart_proc_show(struct seq_file *m, void *v)
 		struct sdio_uart_port *port = sdio_uart_port_get(i);
 		if (port) {
 			seq_printf(m, "%d: uart:SDIO", i);
-			if(capable(CAP_SYS_ADMIN)) {
+			if (capable(CAP_SYS_ADMIN)) {
 				seq_printf(m, " tx:%d rx:%d",
 					      port->icount.tx, port->icount.rx);
 				if (port->icount.frame)
@@ -994,6 +1076,13 @@ static const struct file_operations sdio_uart_proc_fops = {
 	.release	= single_release,
 };
 
+static const struct tty_port_operations sdio_uart_port_ops = {
+	.dtr_rts = uart_dtr_rts,
+	.carrier_raised = uart_carrier_raised,
+	.shutdown = sdio_uart_shutdown,
+	.activate = sdio_uart_activate,
+};
+
 static const struct tty_operations sdio_uart_ops = {
 	.open			= sdio_uart_open,
 	.close			= sdio_uart_close,
@@ -1004,9 +1093,12 @@ static const struct tty_operations sdio_uart_ops = {
 	.throttle		= sdio_uart_throttle,
 	.unthrottle		= sdio_uart_unthrottle,
 	.set_termios		= sdio_uart_set_termios,
+	.hangup			= sdio_uart_hangup,
 	.break_ctl		= sdio_uart_break_ctl,
 	.tiocmget		= sdio_uart_tiocmget,
 	.tiocmset		= sdio_uart_tiocmset,
+	.install		= sdio_uart_install,
+	.cleanup		= sdio_uart_cleanup,
 	.proc_fops		= &sdio_uart_proc_fops,
 };
 
@@ -1043,7 +1135,7 @@ static int sdio_uart_probe(struct sdio_func *func,
 		}
 		if (!tpl) {
 			printk(KERN_WARNING
-			       "%s: can't find tuple 0x91 subtuple 0 (SUBTPL_SIOREG) for GPS class\n",
+       "%s: can't find tuple 0x91 subtuple 0 (SUBTPL_SIOREG) for GPS class\n",
 			       sdio_func_id(func));
 			kfree(port);
 			return -EINVAL;
@@ -1068,13 +1160,16 @@ static int sdio_uart_probe(struct sdio_func *func,
 
 	port->func = func;
 	sdio_set_drvdata(func, port);
+	tty_port_init(&port->port);
+	port->port.ops = &sdio_uart_port_ops;
 
 	ret = sdio_uart_add_port(port);
 	if (ret) {
 		kfree(port);
 	} else {
 		struct device *dev;
-		dev = tty_register_device(sdio_uart_tty_driver, port->index, &func->dev);
+		dev = tty_register_device(sdio_uart_tty_driver,
+						port->index, &func->dev);
 		if (IS_ERR(dev)) {
 			sdio_uart_port_remove(port);
 			ret = PTR_ERR(dev);