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authorJohan Hovold <jhovold@gmail.com>2010-05-16 20:33:50 +0200
committerGreg Kroah-Hartman <gregkh@suse.de>2010-05-20 22:21:49 +0200
commit117fb8d086cfc6e51c729fe5533bb83cb55c150a (patch)
tree638ecc35e7181a482a425250729622cbe2f2016e
parentUSB: cypress_m8: remove unused drain define (diff)
downloadlinux-117fb8d086cfc6e51c729fe5533bb83cb55c150a.tar.xz
linux-117fb8d086cfc6e51c729fe5533bb83cb55c150a.zip
USB: cypress_m8: use kfifo to implement write buffering
Kill custom fifo implementation. Note that cypress_m8 has no port write fifo as it has no bulk-out endpoint. Compile-only tested. Signed-off-by: Johan Hovold <jhovold@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r--drivers/usb/serial/cypress_m8.c239
1 files changed, 17 insertions, 222 deletions
diff --git a/drivers/usb/serial/cypress_m8.c b/drivers/usb/serial/cypress_m8.c
index d96374865289..f5d06746cc3b 100644
--- a/drivers/usb/serial/cypress_m8.c
+++ b/drivers/usb/serial/cypress_m8.c
@@ -64,6 +64,7 @@
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include <linux/serial.h>
+#include <linux/kfifo.h>
#include <linux/delay.h>
#include <linux/uaccess.h>
#include <asm/unaligned.h>
@@ -79,7 +80,7 @@ static int unstable_bauds;
/*
* Version Information
*/
-#define DRIVER_VERSION "v1.09"
+#define DRIVER_VERSION "v1.10"
#define DRIVER_AUTHOR "Lonnie Mendez <dignome@gmail.com>, Neil Whelchel <koyama@firstlight.net>"
#define DRIVER_DESC "Cypress USB to Serial Driver"
@@ -134,7 +135,7 @@ struct cypress_private {
int bytes_out; /* used for statistics */
int cmd_count; /* used for statistics */
int cmd_ctrl; /* always set this to 1 before issuing a command */
- struct cypress_buf *buf; /* write buffer */
+ struct kfifo write_fifo; /* write fifo */
int write_urb_in_use; /* write urb in use indicator */
int write_urb_interval; /* interval to use for write urb */
int read_urb_interval; /* interval to use for read urb */
@@ -156,14 +157,6 @@ struct cypress_private {
struct ktermios tmp_termios; /* stores the old termios settings */
};
-/* write buffer structure */
-struct cypress_buf {
- unsigned int buf_size;
- char *buf_buf;
- char *buf_get;
- char *buf_put;
-};
-
/* function prototypes for the Cypress USB to serial device */
static int cypress_earthmate_startup(struct usb_serial *serial);
static int cypress_hidcom_startup(struct usb_serial *serial);
@@ -189,17 +182,6 @@ static void cypress_unthrottle(struct tty_struct *tty);
static void cypress_set_dead(struct usb_serial_port *port);
static void cypress_read_int_callback(struct urb *urb);
static void cypress_write_int_callback(struct urb *urb);
-/* write buffer functions */
-static struct cypress_buf *cypress_buf_alloc(unsigned int size);
-static void cypress_buf_free(struct cypress_buf *cb);
-static void cypress_buf_clear(struct cypress_buf *cb);
-static unsigned int cypress_buf_data_avail(struct cypress_buf *cb);
-static unsigned int cypress_buf_space_avail(struct cypress_buf *cb);
-static unsigned int cypress_buf_put(struct cypress_buf *cb,
- const char *buf, unsigned int count);
-static unsigned int cypress_buf_get(struct cypress_buf *cb,
- char *buf, unsigned int count);
-
static struct usb_serial_driver cypress_earthmate_device = {
.driver = {
@@ -502,8 +484,7 @@ static int generic_startup(struct usb_serial *serial)
priv->comm_is_ok = !0;
spin_lock_init(&priv->lock);
- priv->buf = cypress_buf_alloc(CYPRESS_BUF_SIZE);
- if (priv->buf == NULL) {
+ if (kfifo_alloc(&priv->write_fifo, CYPRESS_BUF_SIZE, GFP_KERNEL)) {
kfree(priv);
return -ENOMEM;
}
@@ -626,7 +607,7 @@ static void cypress_release(struct usb_serial *serial)
priv = usb_get_serial_port_data(serial->port[0]);
if (priv) {
- cypress_buf_free(priv->buf);
+ kfifo_free(&priv->write_fifo);
kfree(priv);
}
}
@@ -703,6 +684,7 @@ static void cypress_dtr_rts(struct usb_serial_port *port, int on)
static void cypress_close(struct usb_serial_port *port)
{
struct cypress_private *priv = usb_get_serial_port_data(port);
+ unsigned long flags;
dbg("%s - port %d", __func__, port->number);
@@ -712,12 +694,14 @@ static void cypress_close(struct usb_serial_port *port)
mutex_unlock(&port->serial->disc_mutex);
return;
}
- cypress_buf_clear(priv->buf);
+ spin_lock_irqsave(&priv->lock, flags);
+ kfifo_reset_out(&priv->write_fifo);
+ spin_unlock_irqrestore(&priv->lock, flags);
+
dbg("%s - stopping urbs", __func__);
usb_kill_urb(port->interrupt_in_urb);
usb_kill_urb(port->interrupt_out_urb);
-
if (stats)
dev_info(&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
priv->bytes_in, priv->bytes_out, priv->cmd_count);
@@ -729,7 +713,6 @@ static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
const unsigned char *buf, int count)
{
struct cypress_private *priv = usb_get_serial_port_data(port);
- unsigned long flags;
dbg("%s - port %d, %d bytes", __func__, port->number, count);
@@ -744,9 +727,7 @@ static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
if (!count)
return count;
- spin_lock_irqsave(&priv->lock, flags);
- count = cypress_buf_put(priv->buf, buf, count);
- spin_unlock_irqrestore(&priv->lock, flags);
+ count = kfifo_in_locked(&priv->write_fifo, buf, count, &priv->lock);
finish:
cypress_send(port);
@@ -806,9 +787,10 @@ static void cypress_send(struct usb_serial_port *port)
} else
spin_unlock_irqrestore(&priv->lock, flags);
- count = cypress_buf_get(priv->buf, &port->interrupt_out_buffer[offset],
- port->interrupt_out_size-offset);
-
+ count = kfifo_out_locked(&priv->write_fifo,
+ &port->interrupt_out_buffer[offset],
+ port->interrupt_out_size - offset,
+ &priv->lock);
if (count == 0)
return;
@@ -874,7 +856,7 @@ static int cypress_write_room(struct tty_struct *tty)
dbg("%s - port %d", __func__, port->number);
spin_lock_irqsave(&priv->lock, flags);
- room = cypress_buf_space_avail(priv->buf);
+ room = kfifo_avail(&priv->write_fifo);
spin_unlock_irqrestore(&priv->lock, flags);
dbg("%s - returns %d", __func__, room);
@@ -1142,7 +1124,7 @@ static int cypress_chars_in_buffer(struct tty_struct *tty)
dbg("%s - port %d", __func__, port->number);
spin_lock_irqsave(&priv->lock, flags);
- chars = cypress_buf_data_avail(priv->buf);
+ chars = kfifo_len(&priv->write_fifo);
spin_unlock_irqrestore(&priv->lock, flags);
dbg("%s - returns %d", __func__, chars);
@@ -1396,193 +1378,6 @@ static void cypress_write_int_callback(struct urb *urb)
/*****************************************************************************
- * Write buffer functions - buffering code from pl2303 used
- *****************************************************************************/
-
-/*
- * cypress_buf_alloc
- *
- * Allocate a circular buffer and all associated memory.
- */
-
-static struct cypress_buf *cypress_buf_alloc(unsigned int size)
-{
-
- struct cypress_buf *cb;
-
-
- if (size == 0)
- return NULL;
-
- cb = kmalloc(sizeof(struct cypress_buf), GFP_KERNEL);
- if (cb == NULL)
- return NULL;
-
- cb->buf_buf = kmalloc(size, GFP_KERNEL);
- if (cb->buf_buf == NULL) {
- kfree(cb);
- return NULL;
- }
-
- cb->buf_size = size;
- cb->buf_get = cb->buf_put = cb->buf_buf;
-
- return cb;
-
-}
-
-
-/*
- * cypress_buf_free
- *
- * Free the buffer and all associated memory.
- */
-
-static void cypress_buf_free(struct cypress_buf *cb)
-{
- if (cb) {
- kfree(cb->buf_buf);
- kfree(cb);
- }
-}
-
-
-/*
- * cypress_buf_clear
- *
- * Clear out all data in the circular buffer.
- */
-
-static void cypress_buf_clear(struct cypress_buf *cb)
-{
- if (cb != NULL)
- cb->buf_get = cb->buf_put;
- /* equivalent to a get of all data available */
-}
-
-
-/*
- * cypress_buf_data_avail
- *
- * Return the number of bytes of data available in the circular
- * buffer.
- */
-
-static unsigned int cypress_buf_data_avail(struct cypress_buf *cb)
-{
- if (cb != NULL)
- return (cb->buf_size + cb->buf_put - cb->buf_get)
- % cb->buf_size;
- else
- return 0;
-}
-
-
-/*
- * cypress_buf_space_avail
- *
- * Return the number of bytes of space available in the circular
- * buffer.
- */
-
-static unsigned int cypress_buf_space_avail(struct cypress_buf *cb)
-{
- if (cb != NULL)
- return (cb->buf_size + cb->buf_get - cb->buf_put - 1)
- % cb->buf_size;
- else
- return 0;
-}
-
-
-/*
- * cypress_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 cypress_buf_put(struct cypress_buf *cb, const char *buf,
- unsigned int count)
-{
-
- unsigned int len;
-
-
- if (cb == NULL)
- return 0;
-
- len = cypress_buf_space_avail(cb);
- if (count > len)
- count = len;
-
- if (count == 0)
- return 0;
-
- len = cb->buf_buf + cb->buf_size - cb->buf_put;
- if (count > len) {
- memcpy(cb->buf_put, buf, len);
- memcpy(cb->buf_buf, buf+len, count - len);
- cb->buf_put = cb->buf_buf + count - len;
- } else {
- memcpy(cb->buf_put, buf, count);
- if (count < len)
- cb->buf_put += count;
- else /* count == len */
- cb->buf_put = cb->buf_buf;
- }
-
- return count;
-
-}
-
-
-/*
- * cypress_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 cypress_buf_get(struct cypress_buf *cb, char *buf,
- unsigned int count)
-{
-
- unsigned int len;
-
-
- if (cb == NULL)
- return 0;
-
- len = cypress_buf_data_avail(cb);
- if (count > len)
- count = len;
-
- if (count == 0)
- return 0;
-
- len = cb->buf_buf + cb->buf_size - cb->buf_get;
- if (count > len) {
- memcpy(buf, cb->buf_get, len);
- memcpy(buf+len, cb->buf_buf, count - len);
- cb->buf_get = cb->buf_buf + count - len;
- } else {
- memcpy(buf, cb->buf_get, count);
- if (count < len)
- cb->buf_get += count;
- else /* count == len */
- cb->buf_get = cb->buf_buf;
- }
-
- return count;
-
-}
-
-/*****************************************************************************
* Module functions
*****************************************************************************/