--- /dev/null
+From d14fc1a74e846d7851f24fc9519fe87dc12a1231 Mon Sep 17 00:00:00 2001
+From: Libor Pechacek <lpechacek@suse.cz>
+Date: Fri, 14 Jan 2011 14:30:21 +0100
+Subject: USB: serial: handle Data Carrier Detect changes
+
+From: Libor Pechacek <lpechacek@suse.cz>
+
+commit d14fc1a74e846d7851f24fc9519fe87dc12a1231 upstream.
+
+Alan's commit 335f8514f200e63d689113d29cb7253a5c282967 introduced
+.carrier_raised function in several drivers. That also means
+tty_port_block_til_ready can now suspend the process trying to open the serial
+port when Carrier Detect is low and put it into tty_port.open_wait queue. We
+need to wake up the process when Carrier Detect goes high and trigger TTY
+hangup when CD goes low.
+
+Some of the devices do not report modem status line changes, or at least we
+don't understand the status message, so for those we remove .carrier_raised
+again.
+
+Signed-off-by: Libor Pechacek <lpechacek@suse.cz>
+Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
+
+---
+ drivers/usb/serial/ch341.c | 10 ++++++++++
+ drivers/usb/serial/cp210x.c | 13 +------------
+ drivers/usb/serial/digi_acceleport.c | 10 ----------
+ drivers/usb/serial/generic.c | 20 ++++++++++++++++++++
+ drivers/usb/serial/keyspan_pda.c | 17 -----------------
+ drivers/usb/serial/pl2303.c | 11 +++++++++++
+ drivers/usb/serial/spcp8x5.c | 6 +++++-
+ include/linux/usb/serial.h | 3 +++
+ 8 files changed, 50 insertions(+), 40 deletions(-)
+
+--- a/drivers/usb/serial/ch341.c
++++ b/drivers/usb/serial/ch341.c
+@@ -486,12 +486,22 @@ static void ch341_read_int_callback(stru
+ 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);
+ }
+
+--- a/drivers/usb/serial/cp210x.c
++++ b/drivers/usb/serial/cp210x.c
+@@ -49,7 +49,6 @@ static int cp210x_tiocmset_port(struct u
+ 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;
+
+@@ -165,8 +164,7 @@ static struct usb_serial_driver cp210x_d
+ .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 */
+@@ -765,15 +763,6 @@ static int cp210x_tiocmget (struct tty_s
+ 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;
+--- 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_st
+ 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_acc
+ .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_seri
+ 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;
+--- a/drivers/usb/serial/generic.c
++++ b/drivers/usb/serial/generic.c
+@@ -479,6 +479,26 @@ int usb_serial_handle_break(struct usb_s
+ }
+ 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;
+--- a/drivers/usb/serial/keyspan_pda.c
++++ b/drivers/usb/serial/keyspan_pda.c
+@@ -680,22 +680,6 @@ static void keyspan_pda_dtr_rts(struct u
+ }
+ }
+
+-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)
+@@ -882,7 +866,6 @@ static struct usb_serial_driver keyspan_
+ .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,
+--- a/drivers/usb/serial/pl2303.c
++++ b/drivers/usb/serial/pl2303.c
+@@ -677,9 +677,11 @@ static void pl2303_update_line_status(st
+ {
+
+ 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);
+@@ -701,11 +703,20 @@ static void pl2303_update_line_status(st
+
+ /* 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)
+--- 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
+@@ -526,6 +526,10 @@ static void spcp8x5_process_read_urb(str
+ /* 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,
+--- a/include/linux/usb/serial.h
++++ b/include/linux/usb/serial.h
+@@ -345,6 +345,9 @@ extern int usb_serial_generic_prepare_wr
+ extern int usb_serial_handle_sysrq_char(struct usb_serial_port *port,
+ unsigned int ch);
+ extern int usb_serial_handle_break(struct usb_serial_port *port);
++extern void usb_serial_handle_dcd_change(struct usb_serial_port *usb_port,
++ struct tty_struct *tty,
++ unsigned int status);
+
+
+ extern int usb_serial_bus_register(struct usb_serial_driver *device);
projects / thirdparty / kernel / stable-queue.git / commitdiff
