kernel-ark/drivers/usb/misc/rio500.c
Adrian Bunk 3328d9752f USB rio500.c: fix check-after-use
The Coverity checker spotted that we have already oops'ed if "dev"
was NULL in these places.

Since "dev" being NULL isn't possible at these places this patch removes
the NULL checks.

Additionally, I've fixed the formatting of the if's.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-25 12:18:43 -07:00

558 lines
13 KiB
C

/* -*- linux-c -*- */
/*
* Driver for USB Rio 500
*
* Cesar Miquel (miquel@df.uba.ar)
*
* based on hp_scanner.c by David E. Nelson (dnelson@jump.net)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Based upon mouse.c (Brad Keryan) and printer.c (Michael Gee).
*
* Changelog:
* 30/05/2003 replaced lock/unlock kernel with up/down
* Daniele Bellucci bellucda@tiscali.it
* */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/random.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/usb.h>
#include <linux/wait.h>
#include "rio500_usb.h"
/*
* Version Information
*/
#define DRIVER_VERSION "v1.1"
#define DRIVER_AUTHOR "Cesar Miquel <miquel@df.uba.ar>"
#define DRIVER_DESC "USB Rio 500 driver"
#define RIO_MINOR 64
/* stall/wait timeout for rio */
#define NAK_TIMEOUT (HZ)
#define IBUF_SIZE 0x1000
/* Size of the rio buffer */
#define OBUF_SIZE 0x10000
struct rio_usb_data {
struct usb_device *rio_dev; /* init: probe_rio */
unsigned int ifnum; /* Interface number of the USB device */
int isopen; /* nz if open */
int present; /* Device is present on the bus */
char *obuf, *ibuf; /* transfer buffers */
char bulk_in_ep, bulk_out_ep; /* Endpoint assignments */
wait_queue_head_t wait_q; /* for timeouts */
struct mutex lock; /* general race avoidance */
};
static struct rio_usb_data rio_instance;
static int open_rio(struct inode *inode, struct file *file)
{
struct rio_usb_data *rio = &rio_instance;
mutex_lock(&(rio->lock));
if (rio->isopen || !rio->present) {
mutex_unlock(&(rio->lock));
return -EBUSY;
}
rio->isopen = 1;
init_waitqueue_head(&rio->wait_q);
mutex_unlock(&(rio->lock));
info("Rio opened.");
return 0;
}
static int close_rio(struct inode *inode, struct file *file)
{
struct rio_usb_data *rio = &rio_instance;
rio->isopen = 0;
info("Rio closed.");
return 0;
}
static int
ioctl_rio(struct inode *inode, struct file *file, unsigned int cmd,
unsigned long arg)
{
struct RioCommand rio_cmd;
struct rio_usb_data *rio = &rio_instance;
void __user *data;
unsigned char *buffer;
int result, requesttype;
int retries;
int retval=0;
mutex_lock(&(rio->lock));
/* Sanity check to make sure rio is connected, powered, etc */
if (rio->present == 0 || rio->rio_dev == NULL) {
retval = -ENODEV;
goto err_out;
}
switch (cmd) {
case RIO_RECV_COMMAND:
data = (void __user *) arg;
if (data == NULL)
break;
if (copy_from_user(&rio_cmd, data, sizeof(struct RioCommand))) {
retval = -EFAULT;
goto err_out;
}
if (rio_cmd.length < 0 || rio_cmd.length > PAGE_SIZE) {
retval = -EINVAL;
goto err_out;
}
buffer = (unsigned char *) __get_free_page(GFP_KERNEL);
if (buffer == NULL) {
retval = -ENOMEM;
goto err_out;
}
if (copy_from_user(buffer, rio_cmd.buffer, rio_cmd.length)) {
retval = -EFAULT;
free_page((unsigned long) buffer);
goto err_out;
}
requesttype = rio_cmd.requesttype | USB_DIR_IN |
USB_TYPE_VENDOR | USB_RECIP_DEVICE;
dbg
("sending command:reqtype=%0x req=%0x value=%0x index=%0x len=%0x",
requesttype, rio_cmd.request, rio_cmd.value,
rio_cmd.index, rio_cmd.length);
/* Send rio control message */
retries = 3;
while (retries) {
result = usb_control_msg(rio->rio_dev,
usb_rcvctrlpipe(rio-> rio_dev, 0),
rio_cmd.request,
requesttype,
rio_cmd.value,
rio_cmd.index, buffer,
rio_cmd.length,
jiffies_to_msecs(rio_cmd.timeout));
if (result == -ETIMEDOUT)
retries--;
else if (result < 0) {
err("Error executing ioctrl. code = %d", result);
retries = 0;
} else {
dbg("Executed ioctl. Result = %d (data=%02x)",
result, buffer[0]);
if (copy_to_user(rio_cmd.buffer, buffer,
rio_cmd.length)) {
free_page((unsigned long) buffer);
retval = -EFAULT;
goto err_out;
}
retries = 0;
}
/* rio_cmd.buffer contains a raw stream of single byte
data which has been returned from rio. Data is
interpreted at application level. For data that
will be cast to data types longer than 1 byte, data
will be little_endian and will potentially need to
be swapped at the app level */
}
free_page((unsigned long) buffer);
break;
case RIO_SEND_COMMAND:
data = (void __user *) arg;
if (data == NULL)
break;
if (copy_from_user(&rio_cmd, data, sizeof(struct RioCommand))) {
retval = -EFAULT;
goto err_out;
}
if (rio_cmd.length < 0 || rio_cmd.length > PAGE_SIZE) {
retval = -EINVAL;
goto err_out;
}
buffer = (unsigned char *) __get_free_page(GFP_KERNEL);
if (buffer == NULL) {
retval = -ENOMEM;
goto err_out;
}
if (copy_from_user(buffer, rio_cmd.buffer, rio_cmd.length)) {
free_page((unsigned long)buffer);
retval = -EFAULT;
goto err_out;
}
requesttype = rio_cmd.requesttype | USB_DIR_OUT |
USB_TYPE_VENDOR | USB_RECIP_DEVICE;
dbg("sending command: reqtype=%0x req=%0x value=%0x index=%0x len=%0x",
requesttype, rio_cmd.request, rio_cmd.value,
rio_cmd.index, rio_cmd.length);
/* Send rio control message */
retries = 3;
while (retries) {
result = usb_control_msg(rio->rio_dev,
usb_sndctrlpipe(rio-> rio_dev, 0),
rio_cmd.request,
requesttype,
rio_cmd.value,
rio_cmd.index, buffer,
rio_cmd.length,
jiffies_to_msecs(rio_cmd.timeout));
if (result == -ETIMEDOUT)
retries--;
else if (result < 0) {
err("Error executing ioctrl. code = %d", result);
retries = 0;
} else {
dbg("Executed ioctl. Result = %d", result);
retries = 0;
}
}
free_page((unsigned long) buffer);
break;
default:
retval = -ENOTTY;
break;
}
err_out:
mutex_unlock(&(rio->lock));
return retval;
}
static ssize_t
write_rio(struct file *file, const char __user *buffer,
size_t count, loff_t * ppos)
{
DEFINE_WAIT(wait);
struct rio_usb_data *rio = &rio_instance;
unsigned long copy_size;
unsigned long bytes_written = 0;
unsigned int partial;
int result = 0;
int maxretry;
int errn = 0;
int intr;
intr = mutex_lock_interruptible(&(rio->lock));
if (intr)
return -EINTR;
/* Sanity check to make sure rio is connected, powered, etc */
if (rio->present == 0 || rio->rio_dev == NULL) {
mutex_unlock(&(rio->lock));
return -ENODEV;
}
do {
unsigned long thistime;
char *obuf = rio->obuf;
thistime = copy_size =
(count >= OBUF_SIZE) ? OBUF_SIZE : count;
if (copy_from_user(rio->obuf, buffer, copy_size)) {
errn = -EFAULT;
goto error;
}
maxretry = 5;
while (thistime) {
if (!rio->rio_dev) {
errn = -ENODEV;
goto error;
}
if (signal_pending(current)) {
mutex_unlock(&(rio->lock));
return bytes_written ? bytes_written : -EINTR;
}
result = usb_bulk_msg(rio->rio_dev,
usb_sndbulkpipe(rio->rio_dev, 2),
obuf, thistime, &partial, 5000);
dbg("write stats: result:%d thistime:%lu partial:%u",
result, thistime, partial);
if (result == -ETIMEDOUT) { /* NAK - so hold for a while */
if (!maxretry--) {
errn = -ETIME;
goto error;
}
prepare_to_wait(&rio->wait_q, &wait, TASK_INTERRUPTIBLE);
schedule_timeout(NAK_TIMEOUT);
finish_wait(&rio->wait_q, &wait);
continue;
} else if (!result && partial) {
obuf += partial;
thistime -= partial;
} else
break;
};
if (result) {
err("Write Whoops - %x", result);
errn = -EIO;
goto error;
}
bytes_written += copy_size;
count -= copy_size;
buffer += copy_size;
} while (count > 0);
mutex_unlock(&(rio->lock));
return bytes_written ? bytes_written : -EIO;
error:
mutex_unlock(&(rio->lock));
return errn;
}
static ssize_t
read_rio(struct file *file, char __user *buffer, size_t count, loff_t * ppos)
{
DEFINE_WAIT(wait);
struct rio_usb_data *rio = &rio_instance;
ssize_t read_count;
unsigned int partial;
int this_read;
int result;
int maxretry = 10;
char *ibuf;
int intr;
intr = mutex_lock_interruptible(&(rio->lock));
if (intr)
return -EINTR;
/* Sanity check to make sure rio is connected, powered, etc */
if (rio->present == 0 || rio->rio_dev == NULL) {
mutex_unlock(&(rio->lock));
return -ENODEV;
}
ibuf = rio->ibuf;
read_count = 0;
while (count > 0) {
if (signal_pending(current)) {
mutex_unlock(&(rio->lock));
return read_count ? read_count : -EINTR;
}
if (!rio->rio_dev) {
mutex_unlock(&(rio->lock));
return -ENODEV;
}
this_read = (count >= IBUF_SIZE) ? IBUF_SIZE : count;
result = usb_bulk_msg(rio->rio_dev,
usb_rcvbulkpipe(rio->rio_dev, 1),
ibuf, this_read, &partial,
8000);
dbg("read stats: result:%d this_read:%u partial:%u",
result, this_read, partial);
if (partial) {
count = this_read = partial;
} else if (result == -ETIMEDOUT || result == 15) { /* FIXME: 15 ??? */
if (!maxretry--) {
mutex_unlock(&(rio->lock));
err("read_rio: maxretry timeout");
return -ETIME;
}
prepare_to_wait(&rio->wait_q, &wait, TASK_INTERRUPTIBLE);
schedule_timeout(NAK_TIMEOUT);
finish_wait(&rio->wait_q, &wait);
continue;
} else if (result != -EREMOTEIO) {
mutex_unlock(&(rio->lock));
err("Read Whoops - result:%u partial:%u this_read:%u",
result, partial, this_read);
return -EIO;
} else {
mutex_unlock(&(rio->lock));
return (0);
}
if (this_read) {
if (copy_to_user(buffer, ibuf, this_read)) {
mutex_unlock(&(rio->lock));
return -EFAULT;
}
count -= this_read;
read_count += this_read;
buffer += this_read;
}
}
mutex_unlock(&(rio->lock));
return read_count;
}
static struct
file_operations usb_rio_fops = {
.owner = THIS_MODULE,
.read = read_rio,
.write = write_rio,
.ioctl = ioctl_rio,
.open = open_rio,
.release = close_rio,
};
static struct usb_class_driver usb_rio_class = {
.name = "rio500%d",
.fops = &usb_rio_fops,
.minor_base = RIO_MINOR,
};
static int probe_rio(struct usb_interface *intf,
const struct usb_device_id *id)
{
struct usb_device *dev = interface_to_usbdev(intf);
struct rio_usb_data *rio = &rio_instance;
int retval;
info("USB Rio found at address %d", dev->devnum);
retval = usb_register_dev(intf, &usb_rio_class);
if (retval) {
err("Not able to get a minor for this device.");
return -ENOMEM;
}
rio->rio_dev = dev;
if (!(rio->obuf = kmalloc(OBUF_SIZE, GFP_KERNEL))) {
err("probe_rio: Not enough memory for the output buffer");
usb_deregister_dev(intf, &usb_rio_class);
return -ENOMEM;
}
dbg("probe_rio: obuf address:%p", rio->obuf);
if (!(rio->ibuf = kmalloc(IBUF_SIZE, GFP_KERNEL))) {
err("probe_rio: Not enough memory for the input buffer");
usb_deregister_dev(intf, &usb_rio_class);
kfree(rio->obuf);
return -ENOMEM;
}
dbg("probe_rio: ibuf address:%p", rio->ibuf);
mutex_init(&(rio->lock));
usb_set_intfdata (intf, rio);
rio->present = 1;
return 0;
}
static void disconnect_rio(struct usb_interface *intf)
{
struct rio_usb_data *rio = usb_get_intfdata (intf);
usb_set_intfdata (intf, NULL);
if (rio) {
usb_deregister_dev(intf, &usb_rio_class);
mutex_lock(&(rio->lock));
if (rio->isopen) {
rio->isopen = 0;
/* better let it finish - the release will do whats needed */
rio->rio_dev = NULL;
mutex_unlock(&(rio->lock));
return;
}
kfree(rio->ibuf);
kfree(rio->obuf);
info("USB Rio disconnected.");
rio->present = 0;
mutex_unlock(&(rio->lock));
}
}
static struct usb_device_id rio_table [] = {
{ USB_DEVICE(0x0841, 1) }, /* Rio 500 */
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE (usb, rio_table);
static struct usb_driver rio_driver = {
.name = "rio500",
.probe = probe_rio,
.disconnect = disconnect_rio,
.id_table = rio_table,
};
static int __init usb_rio_init(void)
{
int retval;
retval = usb_register(&rio_driver);
if (retval)
goto out;
info(DRIVER_VERSION ":" DRIVER_DESC);
out:
return retval;
}
static void __exit usb_rio_cleanup(void)
{
struct rio_usb_data *rio = &rio_instance;
rio->present = 0;
usb_deregister(&rio_driver);
}
module_init(usb_rio_init);
module_exit(usb_rio_cleanup);
MODULE_AUTHOR( DRIVER_AUTHOR );
MODULE_DESCRIPTION( DRIVER_DESC );
MODULE_LICENSE("GPL");