Add helper to retrieve the available device transfer-buffer space. Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> --- drivers/usb/serial/keyspan_pda.c | 113 ++++++++++++++----------------- 1 file changed, 50 insertions(+), 63 deletions(-) diff --git a/drivers/usb/serial/keyspan_pda.c b/drivers/usb/serial/keyspan_pda.c index 39ed3ad32365..54a21a99c001 100644 --- a/drivers/usb/serial/keyspan_pda.c +++ b/drivers/usb/serial/keyspan_pda.c @@ -98,6 +98,42 @@ static const struct usb_device_id id_table_fake_xircom[] = { }; #endif +static int keyspan_pda_get_write_room(struct keyspan_pda_private *priv) +{ + struct usb_serial_port *port = priv->port; + struct usb_serial *serial = priv->serial; + u8 *room; + int rc; + + room = kmalloc(1, GFP_KERNEL); + if (!room) + return -ENOMEM; + + rc = usb_control_msg(serial->dev, + usb_rcvctrlpipe(serial->dev, 0), + 6, /* write_room */ + USB_TYPE_VENDOR | USB_RECIP_INTERFACE + | USB_DIR_IN, + 0, /* value: 0 means "remaining room" */ + 0, /* index */ + room, + 1, + 2000); + if (rc != 1) { + if (rc >= 0) + rc = -EIO; + dev_dbg(&port->dev, "roomquery failed: %d\n", rc); + goto out_free; + } + + dev_dbg(&port->dev, "roomquery says %d\n", *room); + rc = *room; +out_free: + kfree(room); + + return rc; +} + static void keyspan_pda_request_unthrottle(struct work_struct *work) { struct keyspan_pda_private *priv = @@ -436,7 +472,6 @@ static int keyspan_pda_tiocmset(struct tty_struct *tty, static int keyspan_pda_write(struct tty_struct *tty, struct usb_serial_port *port, const unsigned char *buf, int count) { - struct usb_serial *serial = port->serial; int request_unthrottle = 0; int rc = 0; struct keyspan_pda_private *priv; @@ -479,38 +514,11 @@ static int keyspan_pda_write(struct tty_struct *tty, device how much room it really has. This is done only on scheduler time, since usb_control_msg() sleeps. */ if (count > priv->tx_room && !in_interrupt()) { - u8 *room; - - room = kmalloc(1, GFP_KERNEL); - if (!room) { - rc = -ENOMEM; + rc = keyspan_pda_get_write_room(priv); + if (rc < 0) goto exit; - } - rc = usb_control_msg(serial->dev, - usb_rcvctrlpipe(serial->dev, 0), - 6, /* write_room */ - USB_TYPE_VENDOR | USB_RECIP_INTERFACE - | USB_DIR_IN, - 0, /* value: 0 means "remaining room" */ - 0, /* index */ - room, - 1, - 2000); - if (rc > 0) { - dev_dbg(&port->dev, "roomquery says %d\n", *room); - priv->tx_room = *room; - } - kfree(room); - if (rc < 0) { - dev_dbg(&port->dev, "roomquery failed\n"); - goto exit; - } - if (rc == 0) { - dev_dbg(&port->dev, "roomquery returned 0 bytes\n"); - rc = -EIO; /* device didn't return any data */ - goto exit; - } + priv->tx_room = rc; } if (count >= priv->tx_room) { @@ -614,48 +622,27 @@ static void keyspan_pda_dtr_rts(struct usb_serial_port *port, int on) static int keyspan_pda_open(struct tty_struct *tty, struct usb_serial_port *port) { - struct usb_serial *serial = port->serial; - u8 *room; - int rc = 0; - struct keyspan_pda_private *priv; + struct keyspan_pda_private *priv = usb_get_serial_port_data(port); + int rc; /* find out how much room is in the Tx ring */ - room = kmalloc(1, GFP_KERNEL); - if (!room) - return -ENOMEM; + rc = keyspan_pda_get_write_room(priv); + if (rc < 0) + return rc; - rc = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0), - 6, /* write_room */ - USB_TYPE_VENDOR | USB_RECIP_INTERFACE - | USB_DIR_IN, - 0, /* value */ - 0, /* index */ - room, - 1, - 2000); - if (rc < 0) { - dev_dbg(&port->dev, "%s - roomquery failed\n", __func__); - goto error; - } - if (rc == 0) { - dev_dbg(&port->dev, "%s - roomquery returned 0 bytes\n", __func__); - rc = -EIO; - goto error; - } - priv = usb_get_serial_port_data(port); - priv->tx_room = *room; - priv->tx_throttled = *room ? 0 : 1; + priv->tx_room = rc; + priv->tx_throttled = rc ? 0 : 1; /*Start reading from the device*/ rc = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL); if (rc) { dev_dbg(&port->dev, "%s - usb_submit_urb(read int) failed\n", __func__); - goto error; + return rc; } -error: - kfree(room); - return rc; + + return 0; } + static void keyspan_pda_close(struct usb_serial_port *port) { struct keyspan_pda_private *priv = usb_get_serial_port_data(port); -- 2.26.2