Merge tag 'v3.10.55' into update

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / usb / serial / pl2303.c

diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index 7151659367a0898cec3124e8ee328bf17f57d6bd..a0b58e252073c64b7ebc6fbb4f7fad59676d4ce0 100644 (file)
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -82,6 +82,9 @@ static const struct usb_device_id id_table[] = {
        { USB_DEVICE(YCCABLE_VENDOR_ID, YCCABLE_PRODUCT_ID) },
        { USB_DEVICE(SUPERIAL_VENDOR_ID, SUPERIAL_PRODUCT_ID) },
        { USB_DEVICE(HP_VENDOR_ID, HP_LD220_PRODUCT_ID) },
+       { USB_DEVICE(HP_VENDOR_ID, HP_LD960_PRODUCT_ID) },
+       { USB_DEVICE(HP_VENDOR_ID, HP_LCM220_PRODUCT_ID) },
+       { USB_DEVICE(HP_VENDOR_ID, HP_LCM960_PRODUCT_ID) },
        { USB_DEVICE(CRESSI_VENDOR_ID, CRESSI_EDY_PRODUCT_ID) },
        { USB_DEVICE(ZEAGLE_VENDOR_ID, ZEAGLE_N2ITION3_PRODUCT_ID) },
        { USB_DEVICE(SONY_VENDOR_ID, SONY_QN3USB_PRODUCT_ID) },
@@ -141,6 +144,8 @@ struct pl2303_private {
        spinlock_t lock;
        u8 line_control;
        u8 line_status;
+
+       u8 line_settings[7];
 };
 
 static int pl2303_vendor_read(__u16 value, __u16 index,
@@ -280,11 +285,7 @@ static void pl2303_set_termios(struct tty_struct *tty,
        int baud_floor, baud_ceil;
        int k;
 
-       /* The PL2303 is reported to lose bytes if you change
-          serial settings even to the same values as before. Thus
-          we actually need to filter in this specific case */
-
-       if (!tty_termios_hw_change(&tty->termios, old_termios))
+       if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))
                return;
 
        cflag = tty->termios.c_cflag;
@@ -293,7 +294,8 @@ static void pl2303_set_termios(struct tty_struct *tty,
        if (!buf) {
                dev_err(&port->dev, "%s - out of memory.\n", __func__);
                /* Report back no change occurred */
-               tty->termios = *old_termios;
+               if (old_termios)
+                       tty->termios = *old_termios;
                return;
        }
 
@@ -303,24 +305,22 @@ static void pl2303_set_termios(struct tty_struct *tty,
        dev_dbg(&port->dev, "0xa1:0x21:0:0  %d - %x %x %x %x %x %x %x\n", i,
            buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6]);
 
-       if (cflag & CSIZE) {
-               switch (cflag & CSIZE) {
-               case CS5:
-                       buf[6] = 5;
-                       break;
-               case CS6:
-                       buf[6] = 6;
-                       break;
-               case CS7:
-                       buf[6] = 7;
-                       break;
-               default:
-               case CS8:
-                       buf[6] = 8;
-                       break;
-               }
-               dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
+       switch (cflag & CSIZE) {
+       case CS5:
+               buf[6] = 5;
+               break;
+       case CS6:
+               buf[6] = 6;
+               break;
+       case CS7:
+               buf[6] = 7;
+               break;
+       default:
+       case CS8:
+               buf[6] = 8;
+               break;
        }
+       dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
 
        /* For reference buf[0]:buf[3] baud rate value */
        /* NOTE: Only the values defined in baud_sup are supported !
@@ -423,17 +423,36 @@ static void pl2303_set_termios(struct tty_struct *tty,
                dev_dbg(&port->dev, "parity = none\n");
        }
 
-       i = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
-                           SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
-                           0, 0, buf, 7, 100);
-       dev_dbg(&port->dev, "0x21:0x20:0:0  %d\n", i);
+       /*
+        * Some PL2303 are known to lose bytes if you change serial settings
+        * even to the same values as before. Thus we actually need to filter
+        * in this specific case.
+        *
+        * Note that the tty_termios_hw_change check above is not sufficient
+        * as a previously requested baud rate may differ from the one
+        * actually used (and stored in old_termios).
+        *
+        * NOTE: No additional locking needed for line_settings as it is
+        *       only used in set_termios, which is serialised against itself.
+        */
+       if (!old_termios || memcmp(buf, priv->line_settings, 7)) {
+               i = usb_control_msg(serial->dev,
+                                   usb_sndctrlpipe(serial->dev, 0),
+                                   SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
+                                   0, 0, buf, 7, 100);
+
+               dev_dbg(&port->dev, "0x21:0x20:0:0  %d\n", i);
+
+               if (i == 7)
+                       memcpy(priv->line_settings, buf, 7);
+       }
 
        /* change control lines if we are switching to or from B0 */
        spin_lock_irqsave(&priv->lock, flags);
        control = priv->line_control;
        if ((cflag & CBAUD) == B0)
                priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
-       else if ((old_termios->c_cflag & CBAUD) == B0)
+       else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
                priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
        if (control != priv->line_control) {
                control = priv->line_control;
@@ -492,7 +511,6 @@ static void pl2303_close(struct usb_serial_port *port)
 
 static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
 {
-       struct ktermios tmp_termios;
        struct usb_serial *serial = port->serial;
        struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
        int result;
@@ -508,7 +526,7 @@ static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
 
        /* Setup termios */
        if (tty)
-               pl2303_set_termios(tty, port, &tmp_termios);
+               pl2303_set_termios(tty, port, NULL);
 
        result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
        if (result) {