#include <linux/usb.h>
#include <linux/usb/serial.h>
#include <linux/uaccess.h>
-
+#include <linux/kfifo.h>
static int debug;
.id_table = generic_device_ids,
.usb_driver = &generic_driver,
.num_ports = 1,
- .shutdown = usb_serial_generic_shutdown,
+ .disconnect = usb_serial_generic_disconnect,
+ .release = usb_serial_generic_release,
.throttle = usb_serial_generic_throttle,
.unthrottle = usb_serial_generic_unthrottle,
.resume = usb_serial_generic_resume,
#endif
}
-int usb_serial_generic_open(struct tty_struct *tty,
- struct usb_serial_port *port, struct file *filp)
+int usb_serial_generic_open(struct tty_struct *tty, struct usb_serial_port *port)
{
struct usb_serial *serial = port->serial;
int result = 0;
dbg("%s - port %d", __func__, port->number);
- /* force low_latency on so that our tty_push actually forces the data
- through, otherwise it is scheduled, and with high data rates (like
- with OHCI) data can get lost. */
- if (tty)
- tty->low_latency = 1;
-
/* clear the throttle flags */
spin_lock_irqsave(&port->lock, flags);
port->throttled = 0;
}
}
-int usb_serial_generic_resume(struct usb_serial *serial)
+void usb_serial_generic_close(struct usb_serial_port *port)
{
- struct usb_serial_port *port;
- int i, c = 0, r;
+ dbg("%s - port %d", __func__, port->number);
+ generic_cleanup(port);
+}
-#ifdef CONFIG_PM
- /*
- * If this is an autoresume, don't submit URBs.
- * They will be submitted in the open function instead.
- */
- if (serial->dev->auto_pm)
- return 0;
-#endif
- for (i = 0; i < serial->num_ports; i++) {
- port = serial->port[i];
- if (port->port.count && port->read_urb) {
- r = usb_submit_urb(port->read_urb, GFP_NOIO);
- if (r < 0)
- c++;
+static int usb_serial_multi_urb_write(struct tty_struct *tty,
+ struct usb_serial_port *port, const unsigned char *buf, int count)
+{
+ 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\n", __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;
- return c ? -EIO : 0;
+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;
}
-void usb_serial_generic_close(struct tty_struct *tty,
- struct usb_serial_port *port, struct file *filp)
+/**
+ * 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
+ */
+static int usb_serial_generic_write_start(struct usb_serial_port *port)
{
- dbg("%s - port %d", __func__, port->number);
- generic_cleanup(port);
+ struct usb_serial *serial = port->serial;
+ unsigned char *data;
+ int result;
+ int count;
+ unsigned long flags;
+ bool start_io;
+
+ /* Atomically determine whether we can and need to start a USB
+ * operation. */
+ 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;
+ }
+ 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);
+ if (result) {
+ dev_err(&port->dev,
+ "%s - failed submitting write urb, error %d\n",
+ __func__, result);
+ /* don't have to grab the lock here, as we will
+ retry if != 0 */
+ port->write_urb_busy = 0;
+ } else
+ result = count;
+
+ return result;
}
+/**
+ * usb_serial_generic_write - generic write function for serial USB devices
+ * @tty: Pointer to &struct tty_struct for the device
+ * @port: Pointer to the &usb_serial_port structure for the device
+ * @buf: Pointer to the data to write
+ * @count: Number of bytes to write
+ *
+ * Returns the number of characters actually written, which may be anything
+ * from zero to @count. If an error occurs, it returns the negative errno
+ * value.
+ */
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;
- unsigned char *data;
dbg("%s - port %d", __func__, port->number);
}
/* only do something if we have a bulk out endpoint */
- if (serial->num_bulk_out) {
- unsigned long flags;
- spin_lock_irqsave(&port->lock, flags);
- if (port->write_urb_busy) {
- spin_unlock_irqrestore(&port->lock, flags);
- dbg("%s - already writing", __func__);
- return 0;
- }
- port->write_urb_busy = 1;
- spin_unlock_irqrestore(&port->lock, flags);
-
- count = (count > port->bulk_out_size) ?
- port->bulk_out_size : count;
-
- memcpy(port->write_urb->transfer_buffer, buf, count);
- data = port->write_urb->transfer_buffer;
- usb_serial_debug_data(debug, &port->dev, __func__, count, data);
+ if (!serial->num_bulk_out)
+ return 0;
- /* 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);
+ if (serial->type->max_in_flight_urbs)
+ return usb_serial_multi_urb_write(tty, port,
+ buf, count);
- /* send the data out the bulk port */
- port->write_urb_busy = 1;
- result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
- if (result) {
- dev_err(&port->dev,
- "%s - failed submitting write urb, error %d\n",
- __func__, result);
- /* don't have to grab the lock here, as we will
- retry if != 0 */
- port->write_urb_busy = 0;
- } else
- result = count;
+ count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock);
+ result = usb_serial_generic_write_start(port);
- return result;
- }
+ if (result >= 0)
+ result = count;
- /* no bulk out, so return 0 bytes written */
- return 0;
+ return result;
}
+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;
dbg("%s - port %d", __func__, port->number);
-
- /* FIXME: Locking */
- if (serial->num_bulk_out) {
- if (!(port->write_urb_busy))
- room = port->bulk_out_size;
- }
+ 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 if (serial->num_bulk_out)
+ room = kfifo_avail(&port->write_fifo);
+ spin_unlock_irqrestore(&port->lock, flags);
dbg("%s - returns %d", __func__, room);
return room;
struct usb_serial_port *port = tty->driver_data;
struct usb_serial *serial = port->serial;
int chars = 0;
+ unsigned long flags;
dbg("%s - port %d", __func__, port->number);
- /* FIXME: Locking */
- if (serial->num_bulk_out) {
- if (port->write_urb_busy)
- chars = port->write_urb->transfer_buffer_length;
- }
+ spin_lock_irqsave(&port->lock, flags);
+ if (serial->type->max_in_flight_urbs)
+ chars = port->tx_bytes_flight;
+ else if (serial->num_bulk_out)
+ chars = kfifo_len(&port->write_fifo);
+ spin_unlock_irqrestore(&port->lock, flags);
dbg("%s - returns %d", __func__, chars);
return chars;
}
-static void resubmit_read_urb(struct usb_serial_port *port, gfp_t mem_flags)
+void usb_serial_generic_resubmit_read_urb(struct usb_serial_port *port,
+ gfp_t mem_flags)
{
struct urb *urb = port->read_urb;
struct usb_serial *serial = port->serial;
"%s - failed resubmitting read urb, error %d\n",
__func__, result);
}
+EXPORT_SYMBOL_GPL(usb_serial_generic_resubmit_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)
{
struct urb *urb = port->read_urb;
struct tty_struct *tty = tty_port_tty_get(&port->port);
- int room;
-
- /* Push data to tty */
- if (tty && urb->actual_length) {
- room = tty_buffer_request_room(tty, urb->actual_length);
- if (room) {
- tty_insert_flip_string(tty, urb->transfer_buffer, room);
- tty_flip_buffer_push(tty);
+ char *ch = (char *)urb->transfer_buffer;
+ int i;
+
+ if (!tty)
+ goto done;
+
+ /* 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
+ where the USB serial is not a console anyway */
+ if (!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);
-
- resubmit_read_urb(port, GFP_ATOMIC);
+done:
+ usb_serial_generic_resubmit_read_urb(port, GFP_ATOMIC);
}
void usb_serial_generic_read_bulk_callback(struct urb *urb)
void usb_serial_generic_write_bulk_callback(struct urb *urb)
{
+ unsigned long flags;
struct usb_serial_port *port = urb->context;
int status = urb->status;
dbg("%s - port %d", __func__, port->number);
- port->write_urb_busy = 0;
- if (status) {
- dbg("%s - nonzero write bulk status received: %d",
- __func__, status);
- return;
+ if (port->serial->type->max_in_flight_urbs) {
+ kfree(urb->transfer_buffer);
+
+ 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;
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ if (status) {
+ dbg("%s - nonzero multi-urb write bulk status "
+ "received: %d", __func__, status);
+ return;
+ }
+ } else {
+ port->write_urb_busy = 0;
+
+ if (status) {
+ dbg("%s - nonzero multi-urb write bulk status "
+ "received: %d", __func__, status);
+ kfifo_reset_out(&port->write_fifo);
+ } else
+ usb_serial_generic_write_start(port);
}
+
usb_serial_port_softint(port);
}
EXPORT_SYMBOL_GPL(usb_serial_generic_write_bulk_callback);
if (was_throttled) {
/* Resume reading from device */
- resubmit_read_urb(port, GFP_KERNEL);
+ flush_and_resubmit_read_urb(port);
}
}
-void usb_serial_generic_shutdown(struct usb_serial *serial)
+int usb_serial_handle_sysrq_char(struct tty_struct *tty,
+ struct usb_serial_port *port, unsigned int ch)
+{
+ if (port->sysrq && port->console) {
+ if (ch && time_before(jiffies, port->sysrq)) {
+ handle_sysrq(ch, tty);
+ port->sysrq = 0;
+ return 1;
+ }
+ port->sysrq = 0;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(usb_serial_handle_sysrq_char);
+
+int usb_serial_handle_break(struct usb_serial_port *port)
+{
+ if (!port->sysrq) {
+ port->sysrq = jiffies + HZ*5;
+ return 1;
+ }
+ port->sysrq = 0;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(usb_serial_handle_break);
+
+int usb_serial_generic_resume(struct usb_serial *serial)
+{
+ struct usb_serial_port *port;
+ int i, c = 0, r;
+
+ for (i = 0; i < serial->num_ports; i++) {
+ port = serial->port[i];
+ if (!port->port.count)
+ continue;
+
+ if (port->read_urb) {
+ r = usb_submit_urb(port->read_urb, GFP_NOIO);
+ if (r < 0)
+ c++;
+ }
+
+ if (port->write_urb) {
+ r = usb_serial_generic_write_start(port);
+ if (r < 0)
+ c++;
+ }
+ }
+
+ return c ? -EIO : 0;
+}
+EXPORT_SYMBOL_GPL(usb_serial_generic_resume);
+
+void usb_serial_generic_disconnect(struct usb_serial *serial)
{
int i;
generic_cleanup(serial->port[i]);
}
+void usb_serial_generic_release(struct usb_serial *serial)
+{
+ dbg("%s", __func__);
+}