diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/usb/serial/ftdi_sio.c | 118 |
1 files changed, 91 insertions, 27 deletions
diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c index 051c3a77b41..3bfcc7b9f86 100644 --- a/drivers/usb/serial/ftdi_sio.c +++ b/drivers/usb/serial/ftdi_sio.c @@ -264,7 +264,7 @@ /* * Version Information */ -#define DRIVER_VERSION "v1.4.1" +#define DRIVER_VERSION "v1.4.2" #define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Bill Ryder <bryder@sgi.com>, Kuba Ober <kuba@mareimbrium.org>" #define DRIVER_DESC "USB FTDI Serial Converters Driver" @@ -687,6 +687,8 @@ struct ftdi_private { char prev_status, diff_status; /* Used for TIOCMIWAIT */ __u8 rx_flags; /* receive state flags (throttling) */ spinlock_t rx_lock; /* spinlock for receive state */ + struct work_struct rx_work; + int rx_processed; __u16 interface; /* FT2232C port interface (0 for FT232/245) */ @@ -717,7 +719,7 @@ static int ftdi_write_room (struct usb_serial_port *port); static int ftdi_chars_in_buffer (struct usb_serial_port *port); static void ftdi_write_bulk_callback (struct urb *urb, struct pt_regs *regs); static void ftdi_read_bulk_callback (struct urb *urb, struct pt_regs *regs); -static void ftdi_process_read (struct usb_serial_port *port); +static void ftdi_process_read (void *param); static void ftdi_set_termios (struct usb_serial_port *port, struct termios * old); static int ftdi_tiocmget (struct usb_serial_port *port, struct file *file); static int ftdi_tiocmset (struct usb_serial_port *port, struct file * file, unsigned int set, unsigned int clear); @@ -1387,6 +1389,8 @@ static int ftdi_common_startup (struct usb_serial *serial) port->read_urb->transfer_buffer_length = BUFSZ; } + INIT_WORK(&priv->rx_work, ftdi_process_read, port); + /* Free port's existing write urb and transfer buffer. */ if (port->write_urb) { usb_free_urb (port->write_urb); @@ -1617,6 +1621,7 @@ static int ftdi_open (struct usb_serial_port *port, struct file *filp) spin_unlock_irqrestore(&priv->rx_lock, flags); /* Start reading from the device */ + priv->rx_processed = 0; usb_fill_bulk_urb(port->read_urb, dev, usb_rcvbulkpipe(dev, port->bulk_in_endpointAddress), port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length, @@ -1667,6 +1672,10 @@ static void ftdi_close (struct usb_serial_port *port, struct file *filp) err("Error from RTS LOW urb"); } } /* Note change no line if hupcl is off */ + + /* cancel any scheduled reading */ + cancel_delayed_work(&priv->rx_work); + flush_scheduled_work(); /* shutdown our bulk read */ if (port->read_urb) @@ -1862,23 +1871,14 @@ static void ftdi_read_bulk_callback (struct urb *urb, struct pt_regs *regs) return; } - /* If throttled, delay receive processing until unthrottled. */ - spin_lock(&priv->rx_lock); - if (priv->rx_flags & THROTTLED) { - dbg("Deferring read urb processing until unthrottled"); - priv->rx_flags |= ACTUALLY_THROTTLED; - spin_unlock(&priv->rx_lock); - return; - } - spin_unlock(&priv->rx_lock); - ftdi_process_read(port); } /* ftdi_read_bulk_callback */ -static void ftdi_process_read (struct usb_serial_port *port) +static void ftdi_process_read (void *param) { /* ftdi_process_read */ + struct usb_serial_port *port = (struct usb_serial_port*)param; struct urb *urb; struct tty_struct *tty; struct ftdi_private *priv; @@ -1889,6 +1889,7 @@ static void ftdi_process_read (struct usb_serial_port *port) int result; int need_flip; int packet_offset; + unsigned long flags; dbg("%s - port %d", __FUNCTION__, port->number); @@ -1915,12 +1916,18 @@ static void ftdi_process_read (struct usb_serial_port *port) data = urb->transfer_buffer; - /* The first two bytes of every read packet are status */ - if (urb->actual_length > 2) { - usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data); + if (priv->rx_processed) { + dbg("%s - already processed: %d bytes, %d remain", __FUNCTION__, + priv->rx_processed, + urb->actual_length - priv->rx_processed); } else { - dbg("Status only: %03oo %03oo",data[0],data[1]); - } + /* The first two bytes of every read packet are status */ + if (urb->actual_length > 2) { + usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data); + } else { + dbg("Status only: %03oo %03oo",data[0],data[1]); + } + } /* TO DO -- check for hung up line and handle appropriately: */ @@ -1929,8 +1936,12 @@ static void ftdi_process_read (struct usb_serial_port *port) /* if CD is dropped and the line is not CLOCAL then we should hangup */ need_flip = 0; - for (packet_offset=0; packet_offset < urb->actual_length; packet_offset += PKTSZ) { + for (packet_offset = priv->rx_processed; packet_offset < urb->actual_length; packet_offset += PKTSZ) { + int length; + /* Compare new line status to the old one, signal if different */ + /* N.B. packet may be processed more than once, but differences + * are only processed once. */ if (priv != NULL) { char new_status = data[packet_offset+0] & FTDI_STATUS_B0_MASK; if (new_status != priv->prev_status) { @@ -1940,6 +1951,35 @@ static void ftdi_process_read (struct usb_serial_port *port) } } + length = min(PKTSZ, urb->actual_length-packet_offset)-2; + if (length < 0) { + err("%s - bad packet length: %d", __FUNCTION__, length+2); + length = 0; + } + + /* have to make sure we don't overflow the buffer + with tty_insert_flip_char's */ + if (tty->flip.count+length > TTY_FLIPBUF_SIZE) { + tty_flip_buffer_push(tty); + need_flip = 0; + + if (tty->flip.count != 0) { + /* flip didn't work, this happens when ftdi_process_read() is + * called from ftdi_unthrottle, because TTY_DONT_FLIP is set */ + dbg("%s - flip buffer push failed", __FUNCTION__); + break; + } + } + if (priv->rx_flags & THROTTLED) { + dbg("%s - throttled", __FUNCTION__); + break; + } + if (tty->ldisc.receive_room(tty)-tty->flip.count < length) { + /* break out & wait for throttling/unthrottling to happen */ + dbg("%s - receive room low", __FUNCTION__); + break; + } + /* Handle errors and break */ error_flag = TTY_NORMAL; /* Although the device uses a bitmask and hence can have multiple */ @@ -1962,13 +2002,8 @@ static void ftdi_process_read (struct usb_serial_port *port) error_flag = TTY_FRAME; dbg("FRAMING error"); } - if (urb->actual_length > packet_offset + 2) { - for (i = 2; (i < PKTSZ) && ((i+packet_offset) < urb->actual_length); ++i) { - /* have to make sure we don't overflow the buffer - with tty_insert_flip_char's */ - if(tty->flip.count >= TTY_FLIPBUF_SIZE) { - tty_flip_buffer_push(tty); - } + if (length > 0) { + for (i = 2; i < length+2; i++) { /* Note that the error flag is duplicated for every character received since we don't know which character it applied to */ @@ -2005,6 +2040,35 @@ static void ftdi_process_read (struct usb_serial_port *port) tty_flip_buffer_push(tty); } + if (packet_offset < urb->actual_length) { + /* not completely processed - record progress */ + priv->rx_processed = packet_offset; + dbg("%s - incomplete, %d bytes processed, %d remain", + __FUNCTION__, packet_offset, + urb->actual_length - packet_offset); + /* check if we were throttled while processing */ + spin_lock_irqsave(&priv->rx_lock, flags); + if (priv->rx_flags & THROTTLED) { + priv->rx_flags |= ACTUALLY_THROTTLED; + spin_unlock_irqrestore(&priv->rx_lock, flags); + dbg("%s - deferring remainder until unthrottled", + __FUNCTION__); + return; + } + spin_unlock_irqrestore(&priv->rx_lock, flags); + /* if the port is closed stop trying to read */ + if (port->open_count > 0){ + /* delay processing of remainder */ + schedule_delayed_work(&priv->rx_work, 1); + } else { + dbg("%s - port is closed", __FUNCTION__); + } + return; + } + + /* urb is completely processed */ + priv->rx_processed = 0; + /* if the port is closed stop trying to read */ if (port->open_count > 0){ /* Continue trying to always read */ @@ -2444,7 +2508,7 @@ static void ftdi_unthrottle (struct usb_serial_port *port) spin_unlock_irqrestore(&priv->rx_lock, flags); if (actually_throttled) - ftdi_process_read(port); + schedule_work(&priv->rx_work); } static int __init ftdi_init (void) |