aboutsummaryrefslogtreecommitdiff
path: root/drivers/usb/class/cdc-wdm.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/usb/class/cdc-wdm.c')
-rw-r--r--drivers/usb/class/cdc-wdm.c134
1 files changed, 78 insertions, 56 deletions
diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c
index 18aafcb08fc..189141ca4e0 100644
--- a/drivers/usb/class/cdc-wdm.c
+++ b/drivers/usb/class/cdc-wdm.c
@@ -52,7 +52,8 @@ MODULE_DEVICE_TABLE (usb, wdm_ids);
#define WDM_READ 4
#define WDM_INT_STALL 5
#define WDM_POLL_RUNNING 6
-
+#define WDM_RESPONDING 7
+#define WDM_SUSPENDING 8
#define WDM_MAX 16
@@ -87,9 +88,7 @@ struct wdm_device {
int count;
dma_addr_t shandle;
dma_addr_t ihandle;
- struct mutex wlock;
- struct mutex rlock;
- struct mutex plock;
+ struct mutex lock;
wait_queue_head_t wait;
struct work_struct rxwork;
int werr;
@@ -117,21 +116,22 @@ static void wdm_in_callback(struct urb *urb)
int status = urb->status;
spin_lock(&desc->iuspin);
+ clear_bit(WDM_RESPONDING, &desc->flags);
if (status) {
switch (status) {
case -ENOENT:
dev_dbg(&desc->intf->dev,
"nonzero urb status received: -ENOENT");
- break;
+ goto skip_error;
case -ECONNRESET:
dev_dbg(&desc->intf->dev,
"nonzero urb status received: -ECONNRESET");
- break;
+ goto skip_error;
case -ESHUTDOWN:
dev_dbg(&desc->intf->dev,
"nonzero urb status received: -ESHUTDOWN");
- break;
+ goto skip_error;
case -EPIPE:
dev_err(&desc->intf->dev,
"nonzero urb status received: -EPIPE\n");
@@ -147,6 +147,7 @@ static void wdm_in_callback(struct urb *urb)
desc->reslength = urb->actual_length;
memmove(desc->ubuf + desc->length, desc->inbuf, desc->reslength);
desc->length += desc->reslength;
+skip_error:
wake_up(&desc->wait);
set_bit(WDM_READ, &desc->flags);
@@ -229,13 +230,16 @@ static void wdm_int_callback(struct urb *urb)
desc->response->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
spin_lock(&desc->iuspin);
clear_bit(WDM_READ, &desc->flags);
- if (!test_bit(WDM_DISCONNECTING, &desc->flags)) {
+ set_bit(WDM_RESPONDING, &desc->flags);
+ if (!test_bit(WDM_DISCONNECTING, &desc->flags)
+ && !test_bit(WDM_SUSPENDING, &desc->flags)) {
rv = usb_submit_urb(desc->response, GFP_ATOMIC);
dev_dbg(&desc->intf->dev, "%s: usb_submit_urb %d",
__func__, rv);
}
spin_unlock(&desc->iuspin);
if (rv < 0) {
+ clear_bit(WDM_RESPONDING, &desc->flags);
if (rv == -EPERM)
return;
if (rv == -ENOMEM) {
@@ -305,14 +309,38 @@ static ssize_t wdm_write
if (we < 0)
return -EIO;
- r = mutex_lock_interruptible(&desc->wlock); /* concurrent writes */
+ desc->outbuf = buf = kmalloc(count, GFP_KERNEL);
+ if (!buf) {
+ rv = -ENOMEM;
+ goto outnl;
+ }
+
+ r = copy_from_user(buf, buffer, count);
+ if (r > 0) {
+ kfree(buf);
+ rv = -EFAULT;
+ goto outnl;
+ }
+
+ /* concurrent writes and disconnect */
+ r = mutex_lock_interruptible(&desc->lock);
rv = -ERESTARTSYS;
- if (r)
+ if (r) {
+ kfree(buf);
goto outnl;
+ }
+
+ if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
+ kfree(buf);
+ rv = -ENODEV;
+ goto outnp;
+ }
r = usb_autopm_get_interface(desc->intf);
- if (r < 0)
+ if (r < 0) {
+ kfree(buf);
goto outnp;
+ }
if (!file->f_flags && O_NONBLOCK)
r = wait_event_interruptible(desc->wait, !test_bit(WDM_IN_USE,
@@ -320,24 +348,8 @@ static ssize_t wdm_write
else
if (test_bit(WDM_IN_USE, &desc->flags))
r = -EAGAIN;
- if (r < 0)
- goto out;
-
- if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
- rv = -ENODEV;
- goto out;
- }
-
- desc->outbuf = buf = kmalloc(count, GFP_KERNEL);
- if (!buf) {
- rv = -ENOMEM;
- goto out;
- }
-
- r = copy_from_user(buf, buffer, count);
- if (r > 0) {
+ if (r < 0) {
kfree(buf);
- rv = -EFAULT;
goto out;
}
@@ -374,7 +386,7 @@ static ssize_t wdm_write
out:
usb_autopm_put_interface(desc->intf);
outnp:
- mutex_unlock(&desc->wlock);
+ mutex_unlock(&desc->lock);
outnl:
return rv < 0 ? rv : count;
}
@@ -387,7 +399,7 @@ static ssize_t wdm_read
struct wdm_device *desc = file->private_data;
- rv = mutex_lock_interruptible(&desc->rlock); /*concurrent reads */
+ rv = mutex_lock_interruptible(&desc->lock); /*concurrent reads */
if (rv < 0)
return -ERESTARTSYS;
@@ -424,11 +436,8 @@ retry:
spin_lock_irq(&desc->iuspin);
if (desc->rerr) { /* read completed, error happened */
- int t = desc->rerr;
desc->rerr = 0;
spin_unlock_irq(&desc->iuspin);
- dev_err(&desc->intf->dev,
- "reading had resulted in %d\n", t);
rv = -EIO;
goto err;
}
@@ -465,9 +474,7 @@ retry:
rv = cntr;
err:
- mutex_unlock(&desc->rlock);
- if (rv < 0 && rv != -EAGAIN)
- dev_err(&desc->intf->dev, "wdm_read: exit error\n");
+ mutex_unlock(&desc->lock);
return rv;
}
@@ -533,7 +540,7 @@ static int wdm_open(struct inode *inode, struct file *file)
}
intf->needs_remote_wakeup = 1;
- mutex_lock(&desc->plock);
+ mutex_lock(&desc->lock);
if (!desc->count++) {
rv = usb_submit_urb(desc->validity, GFP_KERNEL);
if (rv < 0) {
@@ -544,7 +551,7 @@ static int wdm_open(struct inode *inode, struct file *file)
} else {
rv = 0;
}
- mutex_unlock(&desc->plock);
+ mutex_unlock(&desc->lock);
usb_autopm_put_interface(desc->intf);
out:
mutex_unlock(&wdm_mutex);
@@ -556,9 +563,9 @@ static int wdm_release(struct inode *inode, struct file *file)
struct wdm_device *desc = file->private_data;
mutex_lock(&wdm_mutex);
- mutex_lock(&desc->plock);
+ mutex_lock(&desc->lock);
desc->count--;
- mutex_unlock(&desc->plock);
+ mutex_unlock(&desc->lock);
if (!desc->count) {
dev_dbg(&desc->intf->dev, "wdm_release: cleanup");
@@ -655,9 +662,7 @@ next_desc:
desc = kzalloc(sizeof(struct wdm_device), GFP_KERNEL);
if (!desc)
goto out;
- mutex_init(&desc->wlock);
- mutex_init(&desc->rlock);
- mutex_init(&desc->plock);
+ mutex_init(&desc->lock);
spin_lock_init(&desc->iuspin);
init_waitqueue_head(&desc->wait);
desc->wMaxCommand = maxcom;
@@ -771,14 +776,17 @@ static void wdm_disconnect(struct usb_interface *intf)
/* to terminate pending flushes */
clear_bit(WDM_IN_USE, &desc->flags);
spin_unlock_irqrestore(&desc->iuspin, flags);
- cancel_work_sync(&desc->rxwork);
+ mutex_lock(&desc->lock);
kill_urbs(desc);
+ cancel_work_sync(&desc->rxwork);
+ mutex_unlock(&desc->lock);
wake_up_all(&desc->wait);
if (!desc->count)
cleanup(desc);
mutex_unlock(&wdm_mutex);
}
+#ifdef CONFIG_PM
static int wdm_suspend(struct usb_interface *intf, pm_message_t message)
{
struct wdm_device *desc = usb_get_intfdata(intf);
@@ -786,22 +794,30 @@ static int wdm_suspend(struct usb_interface *intf, pm_message_t message)
dev_dbg(&desc->intf->dev, "wdm%d_suspend\n", intf->minor);
- mutex_lock(&desc->plock);
-#ifdef CONFIG_PM
+ /* if this is an autosuspend the caller does the locking */
+ if (!(message.event & PM_EVENT_AUTO))
+ mutex_lock(&desc->lock);
+ spin_lock_irq(&desc->iuspin);
+
if ((message.event & PM_EVENT_AUTO) &&
- test_bit(WDM_IN_USE, &desc->flags)) {
+ (test_bit(WDM_IN_USE, &desc->flags)
+ || test_bit(WDM_RESPONDING, &desc->flags))) {
+ spin_unlock_irq(&desc->iuspin);
rv = -EBUSY;
} else {
-#endif
- cancel_work_sync(&desc->rxwork);
+
+ set_bit(WDM_SUSPENDING, &desc->flags);
+ spin_unlock_irq(&desc->iuspin);
+ /* callback submits work - order is essential */
kill_urbs(desc);
-#ifdef CONFIG_PM
+ cancel_work_sync(&desc->rxwork);
}
-#endif
- mutex_unlock(&desc->plock);
+ if (!(message.event & PM_EVENT_AUTO))
+ mutex_unlock(&desc->lock);
return rv;
}
+#endif
static int recover_from_urb_loss(struct wdm_device *desc)
{
@@ -815,23 +831,27 @@ static int recover_from_urb_loss(struct wdm_device *desc)
}
return rv;
}
+
+#ifdef CONFIG_PM
static int wdm_resume(struct usb_interface *intf)
{
struct wdm_device *desc = usb_get_intfdata(intf);
int rv;
dev_dbg(&desc->intf->dev, "wdm%d_resume\n", intf->minor);
- mutex_lock(&desc->plock);
+
+ clear_bit(WDM_SUSPENDING, &desc->flags);
rv = recover_from_urb_loss(desc);
- mutex_unlock(&desc->plock);
+
return rv;
}
+#endif
static int wdm_pre_reset(struct usb_interface *intf)
{
struct wdm_device *desc = usb_get_intfdata(intf);
- mutex_lock(&desc->plock);
+ mutex_lock(&desc->lock);
return 0;
}
@@ -841,7 +861,7 @@ static int wdm_post_reset(struct usb_interface *intf)
int rv;
rv = recover_from_urb_loss(desc);
- mutex_unlock(&desc->plock);
+ mutex_unlock(&desc->lock);
return 0;
}
@@ -849,9 +869,11 @@ static struct usb_driver wdm_driver = {
.name = "cdc_wdm",
.probe = wdm_probe,
.disconnect = wdm_disconnect,
+#ifdef CONFIG_PM
.suspend = wdm_suspend,
.resume = wdm_resume,
.reset_resume = wdm_resume,
+#endif
.pre_reset = wdm_pre_reset,
.post_reset = wdm_post_reset,
.id_table = wdm_ids,