7 files changed, 47 insertions, 40 deletions

diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
index 63f7cc45bcac..7b8815ddf368 100644
--- a/drivers/usb/serial/ch341.c
+++ b/drivers/usb/serial/ch341.c
@@ -486,12 +486,22 @@ static void ch341_read_int_callback(struct urb *urb)
         if (actual_length >= 4) {
                 struct ch341_private *priv = usb_get_serial_port_data(port);
                 unsigned long flags;
+                u8 prev_line_status = priv->line_status;
 
                 spin_lock_irqsave(&priv->lock, flags);
                 priv->line_status = (~(data[2])) & CH341_BITS_MODEM_STAT;
                 if ((data[1] & CH341_MULT_STAT))
                         priv->multi_status_change = 1;
                 spin_unlock_irqrestore(&priv->lock, flags);
+
+                if ((priv->line_status ^ prev_line_status) & CH341_BIT_DCD) {
+                        struct tty_struct *tty = tty_port_tty_get(&port->port);
+                        if (tty)
+                                usb_serial_handle_dcd_change(port, tty,
+                                            priv->line_status & CH341_BIT_DCD);
+                        tty_kref_put(tty);
+                }
+
                 wake_up_interruptible(&priv->delta_msr_wait);
         }
 
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c
index c3bea46e87fb..735ea03157ab 100644
--- a/drivers/usb/serial/cp210x.c
+++ b/drivers/usb/serial/cp210x.c
@@ -49,7 +49,6 @@ static int cp210x_tiocmset_port(struct usb_serial_port *port, struct file *,
 static void cp210x_break_ctl(struct tty_struct *, int);
 static int cp210x_startup(struct usb_serial *);
 static void cp210x_dtr_rts(struct usb_serial_port *p, int on);
-static int cp210x_carrier_raised(struct usb_serial_port *p);
 
 static int debug;
 
@@ -166,8 +165,7 @@ static struct usb_serial_driver cp210x_device = {
         .tiocmget               = cp210x_tiocmget,
         .tiocmset               = cp210x_tiocmset,
         .attach                 = cp210x_startup,
-        .dtr_rts                = cp210x_dtr_rts,
-        .carrier_raised         = cp210x_carrier_raised
+        .dtr_rts                = cp210x_dtr_rts
 };
 
 /* Config request types */
@@ -766,15 +764,6 @@ static int cp210x_tiocmget (struct tty_struct *tty, struct file *file)
         return result;
 }
 
-static int cp210x_carrier_raised(struct usb_serial_port *p)
-{
-        unsigned int control;
-        cp210x_get_config(p, CP210X_GET_MDMSTS, &control, 1);
-        if (control & CONTROL_DCD)
-                return 1;
-        return 0;
-}
-
 static void cp210x_break_ctl (struct tty_struct *tty, int break_state)
 {
         struct usb_serial_port *port = tty->driver_data;
diff --git a/drivers/usb/serial/digi_acceleport.c b/drivers/usb/serial/digi_acceleport.c
index b92070c103cd..666e5a6edd82 100644
--- a/drivers/usb/serial/digi_acceleport.c
+++ b/drivers/usb/serial/digi_acceleport.c
@@ -455,7 +455,6 @@ static int digi_write_room(struct tty_struct *tty);
 static int digi_chars_in_buffer(struct tty_struct *tty);
 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port);
 static void digi_close(struct usb_serial_port *port);
-static int digi_carrier_raised(struct usb_serial_port *port);
 static void digi_dtr_rts(struct usb_serial_port *port, int on);
 static int digi_startup_device(struct usb_serial *serial);
 static int digi_startup(struct usb_serial *serial);
@@ -511,7 +510,6 @@ static struct usb_serial_driver digi_acceleport_2_device = {
         .open =                         digi_open,
         .close =                        digi_close,
         .dtr_rts =                      digi_dtr_rts,
-        .carrier_raised =               digi_carrier_raised,
         .write =                        digi_write,
         .write_room =                   digi_write_room,
         .write_bulk_callback =          digi_write_bulk_callback,
@@ -1339,14 +1337,6 @@ static void digi_dtr_rts(struct usb_serial_port *port, int on)
         digi_set_modem_signals(port, on * (TIOCM_DTR|TIOCM_RTS), 1);
 }
 
-static int digi_carrier_raised(struct usb_serial_port *port)
-{
-        struct digi_port *priv = usb_get_serial_port_data(port);
-        if (priv->dp_modem_signals & TIOCM_CD)
-                return 1;
-        return 0;
-}
-
 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port)
 {
         int ret;
diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c
index e6833e216fc9..e4db5ad2bc55 100644
--- a/drivers/usb/serial/generic.c
+++ b/drivers/usb/serial/generic.c
@@ -479,6 +479,26 @@ int usb_serial_handle_break(struct usb_serial_port *port)
 }
 EXPORT_SYMBOL_GPL(usb_serial_handle_break);
 
+/**
+ *      usb_serial_handle_dcd_change - handle a change of carrier detect state
+ *      @port: usb_serial_port structure for the open port
+ *      @tty: tty_struct structure for the port
+ *      @status: new carrier detect status, nonzero if active
+ */
+void usb_serial_handle_dcd_change(struct usb_serial_port *usb_port,
+                                struct tty_struct *tty, unsigned int status)
+{
+        struct tty_port *port = &usb_port->port;
+
+        dbg("%s - port %d, status %d", __func__, usb_port->number, status);
+
+        if (status)
+                wake_up_interruptible(&port->open_wait);
+        else if (tty && !C_CLOCAL(tty))
+                tty_hangup(tty);
+}
+EXPORT_SYMBOL_GPL(usb_serial_handle_dcd_change);
+
 int usb_serial_generic_resume(struct usb_serial *serial)
 {
         struct usb_serial_port *port;
diff --git a/drivers/usb/serial/keyspan_pda.c b/drivers/usb/serial/keyspan_pda.c
index a10dd5676ccc..554a8693a463 100644
--- a/drivers/usb/serial/keyspan_pda.c
+++ b/drivers/usb/serial/keyspan_pda.c
@@ -679,22 +679,6 @@ static void keyspan_pda_dtr_rts(struct usb_serial_port *port, int on)
         }
 }
 
-static int keyspan_pda_carrier_raised(struct usb_serial_port *port)
-{
-        struct usb_serial *serial = port->serial;
-        unsigned char modembits;
-
-        /* If we can read the modem status and the DCD is low then
-           carrier is not raised yet */
-        if (keyspan_pda_get_modem_info(serial, &modembits) >= 0) {
-                if (!(modembits & (1>>6)))
-                        return 0;
-        }
-        /* Carrier raised, or we failed (eg disconnected) so
-           progress accordingly */
-        return 1;
-}
-
 
 static int keyspan_pda_open(struct tty_struct *tty,
                                         struct usb_serial_port *port)
@@ -881,7 +865,6 @@ static struct usb_serial_driver keyspan_pda_device = {
         .id_table =             id_table_std,
         .num_ports =            1,
         .dtr_rts =              keyspan_pda_dtr_rts,
-        .carrier_raised =       keyspan_pda_carrier_raised,
         .open =                 keyspan_pda_open,
         .close =                keyspan_pda_close,
         .write =                keyspan_pda_write,
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index 45c40e6e9737..08c9181b8e48 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -678,9 +678,11 @@ static void pl2303_update_line_status(struct usb_serial_port *port,
 {
 
         struct pl2303_private *priv = usb_get_serial_port_data(port);
+        struct tty_struct *tty;
         unsigned long flags;
         u8 status_idx = UART_STATE;
         u8 length = UART_STATE + 1;
+        u8 prev_line_status;
         u16 idv, idp;
 
         idv = le16_to_cpu(port->serial->dev->descriptor.idVendor);
@@ -702,11 +704,20 @@ static void pl2303_update_line_status(struct usb_serial_port *port,
 
         /* Save off the uart status for others to look at */
         spin_lock_irqsave(&priv->lock, flags);
+        prev_line_status = priv->line_status;
         priv->line_status = data[status_idx];
         spin_unlock_irqrestore(&priv->lock, flags);
         if (priv->line_status & UART_BREAK_ERROR)
                 usb_serial_handle_break(port);
         wake_up_interruptible(&priv->delta_msr_wait);
+
+        tty = tty_port_tty_get(&port->port);
+        if (!tty)
+                return;
+        if ((priv->line_status ^ prev_line_status) & UART_DCD)
+                usb_serial_handle_dcd_change(port, tty,
+                                priv->line_status & UART_DCD);
+        tty_kref_put(tty);
 }
 
 static void pl2303_read_int_callback(struct urb *urb)
diff --git a/drivers/usb/serial/spcp8x5.c b/drivers/usb/serial/spcp8x5.c
index c7665d39d192..cbfb70bffdd0 100644
--- a/drivers/usb/serial/spcp8x5.c
+++ b/drivers/usb/serial/spcp8x5.c
@@ -133,7 +133,7 @@ struct spcp8x5_usb_ctrl_arg {
 
 /* how come ??? */
 #define UART_STATE                      0x08
-#define UART_STATE_TRANSIENT_MASK       0x74
+#define UART_STATE_TRANSIENT_MASK       0x75
 #define UART_DCD                        0x01
 #define UART_DSR                        0x02
 #define UART_BREAK_ERROR                0x04
@@ -525,6 +525,10 @@ static void spcp8x5_process_read_urb(struct urb *urb)
                 /* overrun is special, not associated with a char */
                 if (status & UART_OVERRUN_ERROR)
                         tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+
+                if (status & UART_DCD)
+                        usb_serial_handle_dcd_change(port, tty,
+                                   priv->line_status & MSR_STATUS_LINE_DCD);
         }
 
         tty_insert_flip_string_fixed_flag(tty, data, tty_flag,