/*
* USB Serial Converter Generic functions
*
+ * Copyright (C) 2010 Johan Hovold (jhovold@gmail.com)
* Copyright (C) 1999 - 2002 Greg Kroah-Hartman (greg@kroah.com)
*
* This program is free software; you can redistribute it and/or
int usb_serial_generic_open(struct tty_struct *tty, struct usb_serial_port *port)
{
- struct usb_serial *serial = port->serial;
int result = 0;
unsigned long flags;
spin_unlock_irqrestore(&port->lock, flags);
/* if we have a bulk endpoint, start reading from it */
- if (port->bulk_in_size) {
- /* Start reading from the device */
- usb_fill_bulk_urb(port->read_urb, serial->dev,
- usb_rcvbulkpipe(serial->dev,
- port->bulk_in_endpointAddress),
- port->read_urb->transfer_buffer,
- port->read_urb->transfer_buffer_length,
- ((serial->type->read_bulk_callback) ?
- serial->type->read_bulk_callback :
- usb_serial_generic_read_bulk_callback),
- port);
- result = usb_submit_urb(port->read_urb, GFP_KERNEL);
- if (result)
- dev_err(&port->dev,
- "%s - failed resubmitting read urb, error %d\n",
- __func__, result);
- }
+ if (port->bulk_in_size)
+ result = usb_serial_generic_submit_read_urb(port, GFP_KERNEL);
return result;
}
static void generic_cleanup(struct usb_serial_port *port)
{
struct usb_serial *serial = port->serial;
+ unsigned long flags;
+ int i;
dbg("%s - port %d", __func__, port->number);
if (serial->dev) {
/* shutdown any bulk transfers that might be going on */
- if (port->bulk_out_size)
+ if (port->bulk_out_size) {
usb_kill_urb(port->write_urb);
+ for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
+ usb_kill_urb(port->write_urbs[i]);
+
+ spin_lock_irqsave(&port->lock, flags);
+ kfifo_reset_out(&port->write_fifo);
+ spin_unlock_irqrestore(&port->lock, flags);
+ }
if (port->bulk_in_size)
usb_kill_urb(port->read_urb);
}
dbg("%s - port %d", __func__, port->number);
generic_cleanup(port);
}
+EXPORT_SYMBOL_GPL(usb_serial_generic_close);
-static int usb_serial_multi_urb_write(struct tty_struct *tty,
- struct usb_serial_port *port, const unsigned char *buf, int count)
+int usb_serial_generic_prepare_write_buffer(struct usb_serial_port *port,
+ void *dest, size_t size)
{
- unsigned long flags;
- struct urb *urb;
- unsigned char *buffer;
- int status;
- int towrite;
- int bwrite = 0;
-
- dbg("%s - port %d", __func__, port->number);
-
- if (count == 0)
- dbg("%s - write request of 0 bytes", __func__);
-
- while (count > 0) {
- towrite = (count > port->bulk_out_size) ?
- port->bulk_out_size : count;
- spin_lock_irqsave(&port->lock, flags);
- if (port->urbs_in_flight >
- port->serial->type->max_in_flight_urbs) {
- spin_unlock_irqrestore(&port->lock, flags);
- dbg("%s - write limit hit", __func__);
- return bwrite;
- }
- port->tx_bytes_flight += towrite;
- port->urbs_in_flight++;
- spin_unlock_irqrestore(&port->lock, flags);
-
- buffer = kmalloc(towrite, GFP_ATOMIC);
- if (!buffer) {
- dev_err(&port->dev,
- "%s ran out of kernel memory for urb ...\n", __func__);
- goto error_no_buffer;
- }
-
- urb = usb_alloc_urb(0, GFP_ATOMIC);
- if (!urb) {
- dev_err(&port->dev, "%s - no more free urbs\n",
- __func__);
- goto error_no_urb;
- }
-
- /* Copy data */
- memcpy(buffer, buf + bwrite, towrite);
- usb_serial_debug_data(debug, &port->dev, __func__,
- towrite, buffer);
- /* fill the buffer and send it */
- usb_fill_bulk_urb(urb, port->serial->dev,
- usb_sndbulkpipe(port->serial->dev,
- port->bulk_out_endpointAddress),
- buffer, towrite,
- usb_serial_generic_write_bulk_callback, port);
-
- status = usb_submit_urb(urb, GFP_ATOMIC);
- if (status) {
- dev_err(&port->dev,
- "%s - failed submitting write urb, error %d\n",
- __func__, status);
- goto error;
- }
-
- /* This urb is the responsibility of the host driver now */
- usb_free_urb(urb);
- dbg("%s write: %d", __func__, towrite);
- count -= towrite;
- bwrite += towrite;
- }
- return bwrite;
-
-error:
- usb_free_urb(urb);
-error_no_urb:
- kfree(buffer);
-error_no_buffer:
- spin_lock_irqsave(&port->lock, flags);
- port->urbs_in_flight--;
- port->tx_bytes_flight -= towrite;
- spin_unlock_irqrestore(&port->lock, flags);
- return bwrite;
+ return kfifo_out_locked(&port->write_fifo, dest, size, &port->lock);
}
/**
* usb_serial_generic_write_start - kick off an URB write
* @port: Pointer to the &struct usb_serial_port data
*
- * Returns the number of bytes queued on success. This will be zero if there
- * was nothing to send. Otherwise, it returns a negative errno value
+ * Returns zero on success, or a negative errno value
*/
static int usb_serial_generic_write_start(struct usb_serial_port *port)
{
- struct usb_serial *serial = port->serial;
- unsigned char *data;
- int result;
- int count;
+ struct urb *urb;
+ int count, result;
unsigned long flags;
- bool start_io;
+ int i;
- /* Atomically determine whether we can and need to start a USB
- * operation. */
+ if (test_and_set_bit_lock(USB_SERIAL_WRITE_BUSY, &port->flags))
+ return 0;
+retry:
spin_lock_irqsave(&port->lock, flags);
- if (port->write_urb_busy)
- start_io = false;
- else {
- start_io = (kfifo_len(&port->write_fifo) != 0);
- port->write_urb_busy = start_io;
+ if (!port->write_urbs_free || !kfifo_len(&port->write_fifo)) {
+ clear_bit_unlock(USB_SERIAL_WRITE_BUSY, &port->flags);
+ spin_unlock_irqrestore(&port->lock, flags);
+ return 0;
}
+ i = (int)find_first_bit(&port->write_urbs_free,
+ ARRAY_SIZE(port->write_urbs));
spin_unlock_irqrestore(&port->lock, flags);
- if (!start_io)
- return 0;
-
- data = port->write_urb->transfer_buffer;
- count = kfifo_out_locked(&port->write_fifo, data, port->bulk_out_size, &port->lock);
- usb_serial_debug_data(debug, &port->dev, __func__, count, data);
-
- /* set up our urb */
- usb_fill_bulk_urb(port->write_urb, serial->dev,
- usb_sndbulkpipe(serial->dev,
- port->bulk_out_endpointAddress),
- port->write_urb->transfer_buffer, count,
- ((serial->type->write_bulk_callback) ?
- serial->type->write_bulk_callback :
- usb_serial_generic_write_bulk_callback),
- port);
-
- /* send the data out the bulk port */
- result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
+ urb = port->write_urbs[i];
+ count = port->serial->type->prepare_write_buffer(port,
+ urb->transfer_buffer,
+ port->bulk_out_size);
+ urb->transfer_buffer_length = count;
+ usb_serial_debug_data(debug, &port->dev, __func__, count,
+ urb->transfer_buffer);
+ result = usb_submit_urb(urb, GFP_ATOMIC);
if (result) {
- dev_err(&port->dev,
- "%s - failed submitting write urb, error %d\n",
+ dev_err(&port->dev, "%s - error submitting urb: %d\n",
__func__, result);
- /* don't have to grab the lock here, as we will
- retry if != 0 */
- port->write_urb_busy = 0;
+ clear_bit_unlock(USB_SERIAL_WRITE_BUSY, &port->flags);
return result;
}
+ clear_bit(i, &port->write_urbs_free);
spin_lock_irqsave(&port->lock, flags);
- port->tx_bytes_flight += count;
+ port->tx_bytes += count;
spin_unlock_irqrestore(&port->lock, flags);
- return count;
+ /* Try sending off another urb, unless in irq context (in which case
+ * there will be no free urb). */
+ if (!in_irq())
+ goto retry;
+
+ clear_bit_unlock(USB_SERIAL_WRITE_BUSY, &port->flags);
+
+ return 0;
}
/**
int usb_serial_generic_write(struct tty_struct *tty,
struct usb_serial_port *port, const unsigned char *buf, int count)
{
- struct usb_serial *serial = port->serial;
int result;
dbg("%s - port %d", __func__, port->number);
if (!port->bulk_out_size)
return -ENODEV;
- if (count == 0) {
- dbg("%s - write request of 0 bytes", __func__);
+ if (!count)
return 0;
- }
-
- if (serial->type->max_in_flight_urbs)
- return usb_serial_multi_urb_write(tty, port,
- buf, count);
count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock);
result = usb_serial_generic_write_start(port);
+ if (result)
+ return result;
- if (result >= 0)
- result = count;
-
- return result;
+ return count;
}
EXPORT_SYMBOL_GPL(usb_serial_generic_write);
int usb_serial_generic_write_room(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
- struct usb_serial *serial = port->serial;
unsigned long flags;
- int room = 0;
+ int room;
dbg("%s - port %d", __func__, port->number);
return 0;
spin_lock_irqsave(&port->lock, flags);
- if (serial->type->max_in_flight_urbs) {
- if (port->urbs_in_flight < serial->type->max_in_flight_urbs)
- room = port->bulk_out_size *
- (serial->type->max_in_flight_urbs -
- port->urbs_in_flight);
- } else {
- room = kfifo_avail(&port->write_fifo);
- }
+ room = kfifo_avail(&port->write_fifo);
spin_unlock_irqrestore(&port->lock, flags);
dbg("%s - returns %d", __func__, room);
int usb_serial_generic_chars_in_buffer(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
- struct usb_serial *serial = port->serial;
unsigned long flags;
int chars;
return 0;
spin_lock_irqsave(&port->lock, flags);
- if (serial->type->max_in_flight_urbs)
- chars = port->tx_bytes_flight;
- else
- chars = kfifo_len(&port->write_fifo) + port->tx_bytes_flight;
+ chars = kfifo_len(&port->write_fifo) + port->tx_bytes;
spin_unlock_irqrestore(&port->lock, flags);
dbg("%s - returns %d", __func__, chars);
return chars;
}
-
-void usb_serial_generic_resubmit_read_urb(struct usb_serial_port *port,
- gfp_t mem_flags)
+int usb_serial_generic_submit_read_urb(struct usb_serial_port *port,
+ gfp_t mem_flags)
{
- struct urb *urb = port->read_urb;
- struct usb_serial *serial = port->serial;
int result;
- /* Continue reading from device */
- usb_fill_bulk_urb(urb, serial->dev,
- usb_rcvbulkpipe(serial->dev,
- port->bulk_in_endpointAddress),
- urb->transfer_buffer,
- urb->transfer_buffer_length,
- ((serial->type->read_bulk_callback) ?
- serial->type->read_bulk_callback :
- usb_serial_generic_read_bulk_callback), port);
-
- result = usb_submit_urb(urb, mem_flags);
+ result = usb_submit_urb(port->read_urb, mem_flags);
if (result && result != -EPERM) {
- dev_err(&port->dev,
- "%s - failed resubmitting read urb, error %d\n",
+ dev_err(&port->dev, "%s - error submitting urb: %d\n",
__func__, result);
}
+ return result;
}
-EXPORT_SYMBOL_GPL(usb_serial_generic_resubmit_read_urb);
+EXPORT_SYMBOL_GPL(usb_serial_generic_submit_read_urb);
-/* Push data to tty layer and resubmit the bulk read URB */
-static void flush_and_resubmit_read_urb(struct usb_serial_port *port)
+void usb_serial_generic_process_read_urb(struct urb *urb)
{
- struct urb *urb = port->read_urb;
- struct tty_struct *tty = tty_port_tty_get(&port->port);
+ struct usb_serial_port *port = urb->context;
+ struct tty_struct *tty;
char *ch = (char *)urb->transfer_buffer;
int i;
+ if (!urb->actual_length)
+ return;
+
+ tty = tty_port_tty_get(&port->port);
if (!tty)
- goto done;
+ return;
/* The per character mucking around with sysrq path it too slow for
stuff like 3G modems, so shortcircuit it in the 99.9999999% of cases
if (!port->port.console || !port->sysrq)
tty_insert_flip_string(tty, ch, urb->actual_length);
else {
- /* Push data to tty */
for (i = 0; i < urb->actual_length; i++, ch++) {
if (!usb_serial_handle_sysrq_char(tty, port, *ch))
tty_insert_flip_char(tty, *ch, TTY_NORMAL);
}
tty_flip_buffer_push(tty);
tty_kref_put(tty);
-done:
- usb_serial_generic_resubmit_read_urb(port, GFP_ATOMIC);
}
+EXPORT_SYMBOL_GPL(usb_serial_generic_process_read_urb);
void usb_serial_generic_read_bulk_callback(struct urb *urb)
{
usb_serial_debug_data(debug, &port->dev, __func__,
urb->actual_length, data);
+ port->serial->type->process_read_urb(urb);
/* Throttle the device if requested by tty */
spin_lock_irqsave(&port->lock, flags);
port->throttled = port->throttle_req;
if (!port->throttled) {
spin_unlock_irqrestore(&port->lock, flags);
- flush_and_resubmit_read_urb(port);
+ usb_serial_generic_submit_read_urb(port, GFP_ATOMIC);
} else
spin_unlock_irqrestore(&port->lock, flags);
}
unsigned long flags;
struct usb_serial_port *port = urb->context;
int status = urb->status;
+ int i;
dbg("%s - port %d", __func__, port->number);
- if (port->serial->type->max_in_flight_urbs) {
- kfree(urb->transfer_buffer);
+ for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
+ if (port->write_urbs[i] == urb)
+ break;
+
+ spin_lock_irqsave(&port->lock, flags);
+ port->tx_bytes -= urb->transfer_buffer_length;
+ set_bit(i, &port->write_urbs_free);
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ if (status) {
+ dbg("%s - non-zero urb status: %d", __func__, status);
spin_lock_irqsave(&port->lock, flags);
- --port->urbs_in_flight;
- port->tx_bytes_flight -= urb->transfer_buffer_length;
- if (port->urbs_in_flight < 0)
- port->urbs_in_flight = 0;
+ kfifo_reset_out(&port->write_fifo);
spin_unlock_irqrestore(&port->lock, flags);
} else {
- spin_lock_irqsave(&port->lock, flags);
- port->tx_bytes_flight -= urb->transfer_buffer_length;
- port->write_urb_busy = 0;
- spin_unlock_irqrestore(&port->lock, flags);
-
- if (status)
- kfifo_reset_out(&port->write_fifo);
- else
- usb_serial_generic_write_start(port);
+ usb_serial_generic_write_start(port);
}
- if (status)
- dbg("%s - non-zero urb status: %d", __func__, status);
-
usb_serial_port_softint(port);
}
EXPORT_SYMBOL_GPL(usb_serial_generic_write_bulk_callback);
port->throttle_req = 1;
spin_unlock_irqrestore(&port->lock, flags);
}
+EXPORT_SYMBOL_GPL(usb_serial_generic_throttle);
void usb_serial_generic_unthrottle(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
int was_throttled;
- unsigned long flags;
dbg("%s - port %d", __func__, port->number);
/* Clear the throttle flags */
- spin_lock_irqsave(&port->lock, flags);
+ spin_lock_irq(&port->lock);
was_throttled = port->throttled;
port->throttled = port->throttle_req = 0;
- spin_unlock_irqrestore(&port->lock, flags);
+ spin_unlock_irq(&port->lock);
- if (was_throttled) {
- /* Resume reading from device */
- flush_and_resubmit_read_urb(port);
- }
+ if (was_throttled)
+ usb_serial_generic_submit_read_urb(port, GFP_KERNEL);
}
+EXPORT_SYMBOL_GPL(usb_serial_generic_unthrottle);
#ifdef CONFIG_MAGIC_SYSRQ
int usb_serial_handle_sysrq_char(struct tty_struct *tty,
c++;
}
- if (port->write_urb) {
+ if (port->bulk_out_size) {
r = usb_serial_generic_write_start(port);
if (r < 0)
c++;
git.openpandora.org / pandora-kernel.git / blobdiff