Commit d733cec1 authored by Johan Hovold's avatar Johan Hovold Committed by Greg Kroah-Hartman
Browse files

USB: io_ti: use kfifo to implement write buffering 



Kill custom fifo implementation.

Compile-only tested.

Signed-off-by: default avatarJohan Hovold <jhovold@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent a3a30f10

drivers/usb/serial/io_ti.c

+13 −210
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ 
#include <linux/spinlock.h>

#include <linux/mutex.h>

#include <linux/serial.h>

#include <linux/kfifo.h>

#include <linux/ioctl.h>

#include <linux/firmware.h>

#include <linux/uaccess.h>
@@ -83,14 +84,6 @@ struct product_info { 
	__u8	hardware_type;		/* Type of hardware */

} __attribute__((packed));



/* circular buffer */

struct edge_buf {

	unsigned int	buf_size;

	char		*buf_buf;

	char		*buf_get;

	char		*buf_put;

};



struct edgeport_port {

	__u16 uart_base;

	__u16 dma_address;
@@ -114,7 +107,7 @@ struct edgeport_port { 
	spinlock_t ep_lock;

	int ep_read_urb_state;

	int ep_write_urb_in_use;

	struct edge_buf *ep_out_buf;

	struct kfifo write_fifo;

};



struct edgeport_serial {
@@ -244,17 +237,6 @@ static void edge_send(struct tty_struct *tty); 
static int edge_create_sysfs_attrs(struct usb_serial_port *port);

static int edge_remove_sysfs_attrs(struct usb_serial_port *port);



/* circular buffer */

static struct edge_buf *edge_buf_alloc(unsigned int size);

static void edge_buf_free(struct edge_buf *eb);

static void edge_buf_clear(struct edge_buf *eb);

static unsigned int edge_buf_data_avail(struct edge_buf *eb);

static unsigned int edge_buf_space_avail(struct edge_buf *eb);

static unsigned int edge_buf_put(struct edge_buf *eb, const char *buf,

	unsigned int count);

static unsigned int edge_buf_get(struct edge_buf *eb, char *buf,

	unsigned int count);





static int ti_vread_sync(struct usb_device *dev, __u8 request,

				__u16 value, __u16 index, u8 *data, int size)
@@ -585,7 +567,7 @@ static void chase_port(struct edgeport_port *port, unsigned long timeout, 
	add_wait_queue(&tty->write_wait, &wait);

	for (;;) {

		set_current_state(TASK_INTERRUPTIBLE);

		if (edge_buf_data_avail(port->ep_out_buf) == 0

		if (kfifo_len(&port->write_fifo) == 0

		|| timeout == 0 || signal_pending(current)

		|| !usb_get_intfdata(port->port->serial->interface))

			/* disconnect */
@@ -597,7 +579,7 @@ static void chase_port(struct edgeport_port *port, unsigned long timeout, 
	set_current_state(TASK_RUNNING);

	remove_wait_queue(&tty->write_wait, &wait);

	if (flush)

		edge_buf_clear(port->ep_out_buf);

		kfifo_reset_out(&port->write_fifo);

	spin_unlock_irqrestore(&port->ep_lock, flags);

	tty_kref_put(tty);
@@ -2084,7 +2066,6 @@ static int edge_write(struct tty_struct *tty, struct usb_serial_port *port, 
				const unsigned char *data, int count)

{

	struct edgeport_port *edge_port = usb_get_serial_port_data(port);

	unsigned long flags;



	dbg("%s - port %d", __func__, port->number);
@@ -2098,10 +2079,8 @@ static int edge_write(struct tty_struct *tty, struct usb_serial_port *port, 
	if (edge_port->close_pending == 1)

		return -ENODEV;



	spin_lock_irqsave(&edge_port->ep_lock, flags);

	count = edge_buf_put(edge_port->ep_out_buf, data, count);

	spin_unlock_irqrestore(&edge_port->ep_lock, flags);



	count = kfifo_in_locked(&edge_port->write_fifo, data, count,

							&edge_port->ep_lock);

	edge_send(tty);



	return count;
@@ -2124,7 +2103,7 @@ static void edge_send(struct tty_struct *tty) 
		return;

	}



	count = edge_buf_get(edge_port->ep_out_buf,

	count = kfifo_out(&edge_port->write_fifo,

				port->write_urb->transfer_buffer,

				port->bulk_out_size);
@@ -2180,7 +2159,7 @@ static int edge_write_room(struct tty_struct *tty) 
		return 0;



	spin_lock_irqsave(&edge_port->ep_lock, flags);

	room = edge_buf_space_avail(edge_port->ep_out_buf);

	room = kfifo_avail(&edge_port->write_fifo);

	spin_unlock_irqrestore(&edge_port->ep_lock, flags);



	dbg("%s - returns %d", __func__, room);
@@ -2202,7 +2181,7 @@ static int edge_chars_in_buffer(struct tty_struct *tty) 
		return 0;



	spin_lock_irqsave(&edge_port->ep_lock, flags);

	chars = edge_buf_data_avail(edge_port->ep_out_buf);

	chars = kfifo_len(&edge_port->write_fifo);

	spin_unlock_irqrestore(&edge_port->ep_lock, flags);



	dbg("%s - returns %d", __func__, chars);
@@ -2659,8 +2638,8 @@ static int edge_startup(struct usb_serial *serial) 
			goto cleanup;

		}

		spin_lock_init(&edge_port->ep_lock);

		edge_port->ep_out_buf = edge_buf_alloc(EDGE_OUT_BUF_SIZE);

		if (edge_port->ep_out_buf == NULL) {

		if (kfifo_alloc(&edge_port->write_fifo, EDGE_OUT_BUF_SIZE,

								GFP_KERNEL)) {

			dev_err(&serial->dev->dev, "%s - Out of memory\n",

								__func__);

			kfree(edge_port);
@@ -2677,7 +2656,7 @@ static int edge_startup(struct usb_serial *serial) 
cleanup:

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

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

		edge_buf_free(edge_port->ep_out_buf);

		kfifo_free(&edge_port->write_fifo);

		kfree(edge_port);

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

	}
@@ -2708,7 +2687,7 @@ static void edge_release(struct usb_serial *serial) 


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

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

		edge_buf_free(edge_port->ep_out_buf);

		kfifo_free(&edge_port->write_fifo);

		kfree(edge_port);

	}

	kfree(usb_get_serial_data(serial));
@@ -2758,182 +2737,6 @@ static int edge_remove_sysfs_attrs(struct usb_serial_port *port) 
}





/* Circular Buffer */



/*

 * edge_buf_alloc

 *

 * Allocate a circular buffer and all associated memory.

 */



static struct edge_buf *edge_buf_alloc(unsigned int size)

{

	struct edge_buf *eb;





	if (size == 0)

		return NULL;



	eb = kmalloc(sizeof(struct edge_buf), GFP_KERNEL);

	if (eb == NULL)

		return NULL;



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

	if (eb->buf_buf == NULL) {

		kfree(eb);

		return NULL;

	}



	eb->buf_size = size;

	eb->buf_get = eb->buf_put = eb->buf_buf;



	return eb;

}





/*

 * edge_buf_free

 *

 * Free the buffer and all associated memory.

 */



static void edge_buf_free(struct edge_buf *eb)

{

	if (eb) {

		kfree(eb->buf_buf);

		kfree(eb);

	}

}





/*

 * edge_buf_clear

 *

 * Clear out all data in the circular buffer.

 */



static void edge_buf_clear(struct edge_buf *eb)

{

	if (eb != NULL)

		eb->buf_get = eb->buf_put;

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

}





/*

 * edge_buf_data_avail

 *

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

 * buffer.

 */



static unsigned int edge_buf_data_avail(struct edge_buf *eb)

{

	if (eb == NULL)

		return 0;

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

}





/*

 * edge_buf_space_avail

 *

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

 * buffer.

 */



static unsigned int edge_buf_space_avail(struct edge_buf *eb)

{

	if (eb == NULL)

		return 0;

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

}





/*

 * edge_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 edge_buf_put(struct edge_buf *eb, const char *buf,

	unsigned int count)

{

	unsigned int len;





	if (eb == NULL)

		return 0;



	len  = edge_buf_space_avail(eb);

	if (count > len)

		count = len;



	if (count == 0)

		return 0;



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

	if (count > len) {

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

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

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

	} else {

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

		if (count < len)

			eb->buf_put += count;

		else /* count == len */

			eb->buf_put = eb->buf_buf;

	}



	return count;

}





/*

 * edge_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 edge_buf_get(struct edge_buf *eb, char *buf,

	unsigned int count)

{

	unsigned int len;





	if (eb == NULL)

		return 0;



	len = edge_buf_data_avail(eb);

	if (count > len)

		count = len;



	if (count == 0)

		return 0;



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

	if (count > len) {

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

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

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

	} else {

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

		if (count < len)

			eb->buf_get += count;

		else /* count == len */

			eb->buf_get = eb->buf_buf;

	}



	return count;

}





static struct usb_serial_driver edgeport_1port_device = {

	.driver = {

		.owner		= THIS_MODULE,