Merge tag 'kvm-s390-master-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git...

[karo-tx-linux.git] / drivers / usb / serial / ch341.c

diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
index 2597b83a8ae254d0eff28b2d2d124ff51c196248..95aa5233726cf86166ae5aad2ea88c446e894d13 100644 (file)
--- a/drivers/usb/serial/ch341.c
+++ b/drivers/usb/serial/ch341.c
@@ -95,6 +95,7 @@ struct ch341_private {
        unsigned baud_rate; /* set baud rate */
        u8 line_control; /* set line control value RTS/DTR */
        u8 line_status; /* active status of modem control inputs */
+       u8 lcr;
 };
 
 static void ch341_set_termios(struct tty_struct *tty,
@@ -112,6 +113,8 @@ static int ch341_control_out(struct usb_device *dev, u8 request,
        r = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), request,
                            USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
                            value, index, NULL, 0, DEFAULT_TIMEOUT);
+       if (r < 0)
+               dev_err(&dev->dev, "failed to send control message: %d\n", r);
 
        return r;
 }
@@ -129,11 +132,24 @@ static int ch341_control_in(struct usb_device *dev,
        r = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), request,
                            USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
                            value, index, buf, bufsize, DEFAULT_TIMEOUT);
-       return r;
+       if (r < bufsize) {
+               if (r >= 0) {
+                       dev_err(&dev->dev,
+                               "short control message received (%d < %u)\n",
+                               r, bufsize);
+                       r = -EIO;
+               }
+
+               dev_err(&dev->dev, "failed to receive control message: %d\n",
+                       r);
+               return r;
+       }
+
+       return 0;
 }
 
-static int ch341_init_set_baudrate(struct usb_device *dev,
-                                  struct ch341_private *priv, unsigned ctrl)
+static int ch341_set_baudrate_lcr(struct usb_device *dev,
+                                 struct ch341_private *priv, u8 lcr)
 {
        short a;
        int r;
@@ -156,9 +172,19 @@ static int ch341_init_set_baudrate(struct usb_device *dev,
        factor = 0x10000 - factor;
        a = (factor & 0xff00) | divisor;
 
-       /* 0x9c is "enable SFR_UART Control register and timer" */
-       r = ch341_control_out(dev, CH341_REQ_SERIAL_INIT,
-                             0x9c | (ctrl << 8), a | 0x80);
+       /*
+        * CH341A buffers data until a full endpoint-size packet (32 bytes)
+        * has been received unless bit 7 is set.
+        */
+       a |= BIT(7);
+
+       r = ch341_control_out(dev, CH341_REQ_WRITE_REG, 0x1312, a);
+       if (r)
+               return r;
+
+       r = ch341_control_out(dev, CH341_REQ_WRITE_REG, 0x2518, lcr);
+       if (r)
+               return r;
 
        return r;
 }
@@ -170,9 +196,9 @@ static int ch341_set_handshake(struct usb_device *dev, u8 control)
 
 static int ch341_get_status(struct usb_device *dev, struct ch341_private *priv)
 {
+       const unsigned int size = 2;
        char *buffer;
        int r;
-       const unsigned size = 8;
        unsigned long flags;
 
        buffer = kmalloc(size, GFP_KERNEL);
@@ -183,14 +209,9 @@ static int ch341_get_status(struct usb_device *dev, struct ch341_private *priv)
        if (r < 0)
                goto out;
 
-       /* setup the private status if available */
-       if (r == 2) {
-               r = 0;
-               spin_lock_irqsave(&priv->lock, flags);
-               priv->line_status = (~(*buffer)) & CH341_BITS_MODEM_STAT;
-               spin_unlock_irqrestore(&priv->lock, flags);
-       } else
-               r = -EPROTO;
+       spin_lock_irqsave(&priv->lock, flags);
+       priv->line_status = (~(*buffer)) & CH341_BITS_MODEM_STAT;
+       spin_unlock_irqrestore(&priv->lock, flags);
 
 out:   kfree(buffer);
        return r;
@@ -200,9 +221,9 @@ out:        kfree(buffer);
 
 static int ch341_configure(struct usb_device *dev, struct ch341_private *priv)
 {
+       const unsigned int size = 2;
        char *buffer;
        int r;
-       const unsigned size = 8;
 
        buffer = kmalloc(size, GFP_KERNEL);
        if (!buffer)
@@ -232,7 +253,7 @@ static int ch341_configure(struct usb_device *dev, struct ch341_private *priv)
        if (r < 0)
                goto out;
 
-       r = ch341_init_set_baudrate(dev, priv, 0);
+       r = ch341_set_baudrate_lcr(dev, priv, priv->lcr);
        if (r < 0)
                goto out;
 
@@ -258,7 +279,6 @@ static int ch341_port_probe(struct usb_serial_port *port)
 
        spin_lock_init(&priv->lock);
        priv->baud_rate = DEFAULT_BAUD_RATE;
-       priv->line_control = CH341_BIT_RTS | CH341_BIT_DTR;
 
        r = ch341_configure(port->serial->dev, priv);
        if (r < 0)
@@ -320,7 +340,7 @@ static int ch341_open(struct tty_struct *tty, struct usb_serial_port *port)
 
        r = ch341_configure(serial->dev, priv);
        if (r)
-               goto out;
+               return r;
 
        if (tty)
                ch341_set_termios(tty, port, NULL);
@@ -330,12 +350,19 @@ static int ch341_open(struct tty_struct *tty, struct usb_serial_port *port)
        if (r) {
                dev_err(&port->dev, "%s - failed to submit interrupt urb: %d\n",
                        __func__, r);
-               goto out;
+               return r;
        }
 
        r = usb_serial_generic_open(tty, port);
+       if (r)
+               goto err_kill_interrupt_urb;
+
+       return 0;
+
+err_kill_interrupt_urb:
+       usb_kill_urb(port->interrupt_in_urb);
 
-out:   return r;
+       return r;
 }
 
 /* Old_termios contains the original termios settings and
@@ -356,7 +383,6 @@ static void ch341_set_termios(struct tty_struct *tty,
 
        baud_rate = tty_get_baud_rate(tty);
 
-       priv->baud_rate = baud_rate;
        ctrl = CH341_LCR_ENABLE_RX | CH341_LCR_ENABLE_TX;
 
        switch (C_CSIZE(tty)) {
@@ -386,22 +412,25 @@ static void ch341_set_termios(struct tty_struct *tty,
                ctrl |= CH341_LCR_STOP_BITS_2;
 
        if (baud_rate) {
-               spin_lock_irqsave(&priv->lock, flags);
-               priv->line_control |= (CH341_BIT_DTR | CH341_BIT_RTS);
-               spin_unlock_irqrestore(&priv->lock, flags);
-               r = ch341_init_set_baudrate(port->serial->dev, priv, ctrl);
+               priv->baud_rate = baud_rate;
+
+               r = ch341_set_baudrate_lcr(port->serial->dev, priv, ctrl);
                if (r < 0 && old_termios) {
                        priv->baud_rate = tty_termios_baud_rate(old_termios);
                        tty_termios_copy_hw(&tty->termios, old_termios);
+               } else if (r == 0) {
+                       priv->lcr = ctrl;
                }
-       } else {
-               spin_lock_irqsave(&priv->lock, flags);
-               priv->line_control &= ~(CH341_BIT_DTR | CH341_BIT_RTS);
-               spin_unlock_irqrestore(&priv->lock, flags);
        }
 
-       ch341_set_handshake(port->serial->dev, priv->line_control);
+       spin_lock_irqsave(&priv->lock, flags);
+       if (C_BAUD(tty) == B0)
+               priv->line_control &= ~(CH341_BIT_DTR | CH341_BIT_RTS);
+       else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
+               priv->line_control |= (CH341_BIT_DTR | CH341_BIT_RTS);
+       spin_unlock_irqrestore(&priv->lock, flags);
 
+       ch341_set_handshake(port->serial->dev, priv->line_control);
 }
 
 static void ch341_break_ctl(struct tty_struct *tty, int break_state)
@@ -576,14 +605,23 @@ static int ch341_tiocmget(struct tty_struct *tty)
 
 static int ch341_reset_resume(struct usb_serial *serial)
 {
-       struct ch341_private *priv;
-
-       priv = usb_get_serial_port_data(serial->port[0]);
+       struct usb_serial_port *port = serial->port[0];
+       struct ch341_private *priv = usb_get_serial_port_data(port);
+       int ret;
 
        /* reconfigure ch341 serial port after bus-reset */
        ch341_configure(serial->dev, priv);
 
-       return 0;
+       if (tty_port_initialized(&port->port)) {
+               ret = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
+               if (ret) {
+                       dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
+                               ret);
+                       return ret;
+               }
+       }
+
+       return usb_serial_generic_resume(serial);
 }
 
 static struct usb_serial_driver ch341_device = {