Commit 684c6e30 authored by Johan Hovold's avatar Johan Hovold Committed by Greg Kroah-Hartman
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USB: pl2303: switch to generic write implementation 



Replace custom fifo-based write implementation with the generic
kfifo-based one.

Signed-off-by: default avatarJohan Hovold <jhovold@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 50a5f70c

drivers/usb/serial/pl2303.c

+4 −326
Original line number Diff line number Diff line
@@ -40,16 +40,6 @@ static int debug; 


#define PL2303_CLOSING_WAIT	(30*HZ)



#define PL2303_BUF_SIZE		1024

#define PL2303_TMP_BUF_SIZE	1024



struct pl2303_buf {

	unsigned int	buf_size;

	char		*buf_buf;

	char		*buf_get;

	char		*buf_put;

};



static const struct usb_device_id id_table[] = {

	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID) },

	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ2) },
@@ -157,173 +147,12 @@ enum pl2303_type { 


struct pl2303_private {

	spinlock_t lock;

	struct pl2303_buf *buf;

	int write_urb_in_use;

	wait_queue_head_t delta_msr_wait;

	u8 line_control;

	u8 line_status;

	enum pl2303_type type;

};



/*

 * pl2303_buf_alloc

 *

 * Allocate a circular buffer and all associated memory.

 */

static struct pl2303_buf *pl2303_buf_alloc(unsigned int size)

{

	struct pl2303_buf *pb;



	if (size == 0)

		return NULL;



	pb = kmalloc(sizeof(struct pl2303_buf), GFP_KERNEL);

	if (pb == NULL)

		return NULL;



	pb->buf_buf = kmalloc(size, GFP_KERNEL);

	if (pb->buf_buf == NULL) {

		kfree(pb);

		return NULL;

	}



	pb->buf_size = size;

	pb->buf_get = pb->buf_put = pb->buf_buf;



	return pb;

}



/*

 * pl2303_buf_free

 *

 * Free the buffer and all associated memory.

 */

static void pl2303_buf_free(struct pl2303_buf *pb)

{

	if (pb) {

		kfree(pb->buf_buf);

		kfree(pb);

	}

}



/*

 * pl2303_buf_clear

 *

 * Clear out all data in the circular buffer.

 */

static void pl2303_buf_clear(struct pl2303_buf *pb)

{

	if (pb != NULL)

		pb->buf_get = pb->buf_put;

		/* equivalent to a get of all data available */

}



/*

 * pl2303_buf_data_avail

 *

 * Return the number of bytes of data available in the circular

 * buffer.

 */

static unsigned int pl2303_buf_data_avail(struct pl2303_buf *pb)

{

	if (pb == NULL)

		return 0;



	return (pb->buf_size + pb->buf_put - pb->buf_get) % pb->buf_size;

}



/*

 * pl2303_buf_space_avail

 *

 * Return the number of bytes of space available in the circular

 * buffer.

 */

static unsigned int pl2303_buf_space_avail(struct pl2303_buf *pb)

{

	if (pb == NULL)

		return 0;



	return (pb->buf_size + pb->buf_get - pb->buf_put - 1) % pb->buf_size;

}



/*

 * pl2303_buf_put

 *

 * Copy data data from a user buffer and put it into the circular buffer.

 * Restrict to the amount of space available.

 *

 * Return the number of bytes copied.

 */

static unsigned int pl2303_buf_put(struct pl2303_buf *pb, const char *buf,

				   unsigned int count)

{

	unsigned int len;



	if (pb == NULL)

		return 0;



	len  = pl2303_buf_space_avail(pb);

	if (count > len)

		count = len;



	if (count == 0)

		return 0;



	len = pb->buf_buf + pb->buf_size - pb->buf_put;

	if (count > len) {

		memcpy(pb->buf_put, buf, len);

		memcpy(pb->buf_buf, buf+len, count - len);

		pb->buf_put = pb->buf_buf + count - len;

	} else {

		memcpy(pb->buf_put, buf, count);

		if (count < len)

			pb->buf_put += count;

		else /* count == len */

			pb->buf_put = pb->buf_buf;

	}



	return count;

}



/*

 * pl2303_buf_get

 *

 * Get data from the circular buffer and copy to the given buffer.

 * Restrict to the amount of data available.

 *

 * Return the number of bytes copied.

 */

static unsigned int pl2303_buf_get(struct pl2303_buf *pb, char *buf,

				   unsigned int count)

{

	unsigned int len;



	if (pb == NULL)

		return 0;



	len = pl2303_buf_data_avail(pb);

	if (count > len)

		count = len;



	if (count == 0)

		return 0;



	len = pb->buf_buf + pb->buf_size - pb->buf_get;

	if (count > len) {

		memcpy(buf, pb->buf_get, len);

		memcpy(buf+len, pb->buf_buf, count - len);

		pb->buf_get = pb->buf_buf + count - len;

	} else {

		memcpy(buf, pb->buf_get, count);

		if (count < len)

			pb->buf_get += count;

		else /* count == len */

			pb->buf_get = pb->buf_buf;

	}



	return count;

}



static int pl2303_vendor_read(__u16 value, __u16 index,

		struct usb_serial *serial, unsigned char *buf)

{
@@ -372,11 +201,6 @@ static int pl2303_startup(struct usb_serial *serial) 
		if (!priv)

			goto cleanup;

		spin_lock_init(&priv->lock);

		priv->buf = pl2303_buf_alloc(PL2303_BUF_SIZE);

		if (priv->buf == NULL) {

			kfree(priv);

			goto cleanup;

		}

		init_waitqueue_head(&priv->delta_msr_wait);

		priv->type = type;

		usb_set_serial_port_data(serial->port[i], priv);
@@ -404,7 +228,6 @@ static int pl2303_startup(struct usb_serial *serial) 
	kfree(buf);

	for (--i; i >= 0; --i) {

		priv = usb_get_serial_port_data(serial->port[i]);

		pl2303_buf_free(priv->buf);

		kfree(priv);

		usb_set_serial_port_data(serial->port[i], NULL);

	}
@@ -422,102 +245,6 @@ static int set_control_lines(struct usb_device *dev, u8 value) 
	return retval;

}



static void pl2303_send(struct usb_serial_port *port)

{

	int count, result;

	struct pl2303_private *priv = usb_get_serial_port_data(port);

	unsigned long flags;



	dbg("%s - port %d", __func__, port->number);



	spin_lock_irqsave(&priv->lock, flags);



	if (priv->write_urb_in_use) {

		spin_unlock_irqrestore(&priv->lock, flags);

		return;

	}



	count = pl2303_buf_get(priv->buf, port->write_urb->transfer_buffer,

			       port->bulk_out_size);



	if (count == 0) {

		spin_unlock_irqrestore(&priv->lock, flags);

		return;

	}



	priv->write_urb_in_use = 1;



	spin_unlock_irqrestore(&priv->lock, flags);



	usb_serial_debug_data(debug, &port->dev, __func__, count,

			      port->write_urb->transfer_buffer);



	port->write_urb->transfer_buffer_length = count;

	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);

		priv->write_urb_in_use = 0;

		/* TODO: reschedule pl2303_send */

	}



	usb_serial_port_softint(port);

}



static int pl2303_write(struct tty_struct *tty, struct usb_serial_port *port,

				const unsigned char *buf, int count)

{

	struct pl2303_private *priv = usb_get_serial_port_data(port);

	unsigned long flags;



	dbg("%s - port %d, %d bytes", __func__, port->number, count);



	if (!count)

		return count;



	spin_lock_irqsave(&priv->lock, flags);

	count = pl2303_buf_put(priv->buf, buf, count);

	spin_unlock_irqrestore(&priv->lock, flags);



	pl2303_send(port);



	return count;

}



static int pl2303_write_room(struct tty_struct *tty)

{

	struct usb_serial_port *port = tty->driver_data;

	struct pl2303_private *priv = usb_get_serial_port_data(port);

	int room = 0;

	unsigned long flags;



	dbg("%s - port %d", __func__, port->number);



	spin_lock_irqsave(&priv->lock, flags);

	room = pl2303_buf_space_avail(priv->buf);

	spin_unlock_irqrestore(&priv->lock, flags);



	dbg("%s - returns %d", __func__, room);

	return room;

}



static int pl2303_chars_in_buffer(struct tty_struct *tty)

{

	struct usb_serial_port *port = tty->driver_data;

	struct pl2303_private *priv = usb_get_serial_port_data(port);

	int chars = 0;

	unsigned long flags;



	dbg("%s - port %d", __func__, port->number);



	spin_lock_irqsave(&priv->lock, flags);

	chars = pl2303_buf_data_avail(priv->buf);

	spin_unlock_irqrestore(&priv->lock, flags);



	dbg("%s - returns %d", __func__, chars);

	return chars;

}



static void pl2303_set_termios(struct tty_struct *tty,

		struct usb_serial_port *port, struct ktermios *old_termios)

{
@@ -729,15 +456,14 @@ static void pl2303_dtr_rts(struct usb_serial_port *port, int on) 


static void pl2303_close(struct usb_serial_port *port)

{

	struct pl2303_private *priv = usb_get_serial_port_data(port);

	unsigned long flags;



	dbg("%s - port %d", __func__, port->number);



	spin_lock_irqsave(&priv->lock, flags);

	spin_lock_irqsave(&port->lock, flags);

	/* clear out any remaining data in the buffer */

	pl2303_buf_clear(priv->buf);

	spin_unlock_irqrestore(&priv->lock, flags);

	kfifo_reset_out(&port->write_fifo);

	spin_unlock_irqrestore(&port->lock, flags);



	/* shutdown our urbs */

	dbg("%s - shutting down urbs", __func__);
@@ -951,12 +677,9 @@ static void pl2303_release(struct usb_serial *serial) 


	for (i = 0; i < serial->num_ports; ++i) {

		priv = usb_get_serial_port_data(serial->port[i]);

		if (priv) {

			pl2303_buf_free(priv->buf);

		kfree(priv);

	}

}

}



static void pl2303_update_line_status(struct usb_serial_port *port,

				      unsigned char *data,
@@ -1086,47 +809,6 @@ static void pl2303_process_read_urb(struct urb *urb) 
	tty_kref_put(tty);

}



static void pl2303_write_bulk_callback(struct urb *urb)

{

	struct usb_serial_port *port =  urb->context;

	struct pl2303_private *priv = usb_get_serial_port_data(port);

	int result;

	int status = urb->status;



	dbg("%s - port %d", __func__, port->number);



	switch (status) {

	case 0:

		/* success */

		break;

	case -ECONNRESET:

	case -ENOENT:

	case -ESHUTDOWN:

		/* this urb is terminated, clean up */

		dbg("%s - urb shutting down with status: %d", __func__,

		    status);

		priv->write_urb_in_use = 0;

		return;

	default:

		/* error in the urb, so we have to resubmit it */

		dbg("%s - Overflow in write", __func__);

		dbg("%s - nonzero write bulk status received: %d", __func__,

		    status);

		port->write_urb->transfer_buffer_length = 1;

		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);

		if (result)

			dev_err(&urb->dev->dev, "%s - failed resubmitting write"

				" urb, error %d\n", __func__, result);

		else

			return;

	}



	priv->write_urb_in_use = 0;



	/* send any buffered data */

	pl2303_send(port);

}



/* All of the device info needed for the PL2303 SIO serial converter */

static struct usb_serial_driver pl2303_device = {

	.driver = {
@@ -1142,7 +824,6 @@ static struct usb_serial_driver pl2303_device = { 
	.close =		pl2303_close,

	.dtr_rts = 		pl2303_dtr_rts,

	.carrier_raised =	pl2303_carrier_raised,

	.write =		pl2303_write,

	.ioctl =		pl2303_ioctl,

	.break_ctl =		pl2303_break_ctl,

	.set_termios =		pl2303_set_termios,
@@ -1150,9 +831,6 @@ static struct usb_serial_driver pl2303_device = { 
	.tiocmset =		pl2303_tiocmset,

	.process_read_urb =	pl2303_process_read_urb,

	.read_int_callback =	pl2303_read_int_callback,

	.write_bulk_callback =	pl2303_write_bulk_callback,

	.write_room =		pl2303_write_room,

	.chars_in_buffer =	pl2303_chars_in_buffer,

	.attach =		pl2303_startup,

	.release =		pl2303_release,

};