redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

USB: autosuspend for cdc-wdm 

this patch implements

- suspend/resume
- aggressive autosuspend for the cdc-wdm driver
- pre/post_reset

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
hifive-unleashed-5.1
Oliver Neukum 2008-06-24 15:56:10 +02:00 committed by Greg Kroah-Hartman
parent 11ea859d64
commit 17d80d562f
1 changed files with 101 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

107
drivers/usb/class/cdc-wdm.c
View File

@ -88,6 +88,7 @@ struct wdm_device {
dma_addr_t ihandle;
struct mutex wlock;
struct mutex rlock;
struct mutex plock;
wait_queue_head_t wait;
struct work_struct rxwork;
int werr;
@ -248,6 +249,7 @@ exit:
static void kill_urbs(struct wdm_device *desc)
{
/* the order here is essential */
usb_kill_urb(desc->command);
usb_kill_urb(desc->validity);
usb_kill_urb(desc->response);
@ -300,6 +302,9 @@ static ssize_t wdm_write
if (r)
goto outnl;
r = usb_autopm_get_interface(desc->intf);
if (r < 0)
goto outnp;
r = wait_event_interruptible(desc->wait, !test_bit(WDM_IN_USE,
&desc->flags));
if (r < 0)
@ -354,6 +359,8 @@ static ssize_t wdm_write
req->wIndex);
}
out:
usb_autopm_put_interface(desc->intf);
outnp:
mutex_unlock(&desc->wlock);
outnl:
return rv < 0 ? rv : count;
@ -378,6 +385,11 @@ retry:
rv = wait_event_interruptible(desc->wait,
test_bit(WDM_READ, &desc->flags));
if (test_bit(WDM_DISCONNECTING, &desc->flags)) {
rv = -ENODEV;
goto err;
}
usb_mark_last_busy(interface_to_usbdev(desc->intf));
if (rv < 0) {
rv = -ERESTARTSYS;
goto err;
@ -485,18 +497,28 @@ static int wdm_open(struct inode *inode, struct file *file)
if (test_bit(WDM_DISCONNECTING, &desc->flags))
goto out;
desc->count++;
;
file->private_data = desc;
rv = usb_submit_urb(desc->validity, GFP_KERNEL);
rv = usb_autopm_get_interface(desc->intf);
if (rv < 0) {
desc->count--;
err("Error submitting int urb - %d", rv);
err("Error autopm - %d", rv);
goto out;
}
rv = 0;
intf->needs_remote_wakeup = 1;
mutex_lock(&desc->plock);
if (!desc->count++) {
rv = usb_submit_urb(desc->validity, GFP_KERNEL);
if (rv < 0) {
desc->count--;
err("Error submitting int urb - %d", rv);
}
} else {
rv = 0;
}
mutex_unlock(&desc->plock);
usb_autopm_put_interface(desc->intf);
out:
mutex_unlock(&wdm_mutex);
return rv;
@ -507,10 +529,15 @@ 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);
desc->count--;
mutex_unlock(&desc->plock);
if (!desc->count) {
dev_dbg(&desc->intf->dev, "wdm_release: cleanup");
kill_urbs(desc);
if (!test_bit(WDM_DISCONNECTING, &desc->flags))
desc->intf->needs_remote_wakeup = 0;
}
mutex_unlock(&wdm_mutex);
return 0;
@ -602,6 +629,7 @@ next_desc:
goto out;
mutex_init(&desc->wlock);
mutex_init(&desc->rlock);
mutex_init(&desc->plock);
spin_lock_init(&desc->iuspin);
init_waitqueue_head(&desc->wait);
desc->wMaxCommand = maxcom;
@ -703,6 +731,7 @@ static void wdm_disconnect(struct usb_interface *intf)
spin_lock_irqsave(&desc->iuspin, flags);
set_bit(WDM_DISCONNECTING, &desc->flags);
set_bit(WDM_READ, &desc->flags);
/* to terminate pending flushes */
clear_bit(WDM_IN_USE, &desc->flags);
spin_unlock_irqrestore(&desc->iuspin, flags);
cancel_work_sync(&desc->rxwork);
@ -713,11 +742,77 @@ static void wdm_disconnect(struct usb_interface *intf)
mutex_unlock(&wdm_mutex);
}
static int wdm_suspend(struct usb_interface *intf, pm_message_t message)
{
struct wdm_device *desc = usb_get_intfdata(intf);
int rv = 0;
dev_dbg(&desc->intf->dev, "wdm%d_suspend\n", intf->minor);
mutex_lock(&desc->plock);
if (interface_to_usbdev(desc->intf)->auto_pm && test_bit(WDM_IN_USE, &desc->flags)) {
rv = -EBUSY;
} else {
cancel_work_sync(&desc->rxwork);
kill_urbs(desc);
}
mutex_unlock(&desc->plock);
return rv;
}
static int recover_from_urb_loss(struct wdm_device *desc)
{
int rv = 0;
if (desc->count) {
rv = usb_submit_urb(desc->validity, GFP_NOIO);
if (rv < 0)
err("Error resume submitting int urb - %d", rv);
}
return rv;
}
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);
rv = recover_from_urb_loss(desc);
mutex_unlock(&desc->plock);
return rv;
}
static int wdm_pre_reset(struct usb_interface *intf)
{
struct wdm_device *desc = usb_get_intfdata(intf);
mutex_lock(&desc->plock);
return 0;
}
static int wdm_post_reset(struct usb_interface *intf)
{
struct wdm_device *desc = usb_get_intfdata(intf);
int rv;
rv = recover_from_urb_loss(desc);
mutex_unlock(&desc->plock);
return 0;
}
static struct usb_driver wdm_driver = {
.name = "cdc_wdm",
.probe = wdm_probe,
.disconnect = wdm_disconnect,
.suspend = wdm_suspend,
.resume = wdm_resume,
.reset_resume = wdm_resume,
.pre_reset = wdm_pre_reset,
.post_reset = wdm_post_reset,
.id_table = wdm_ids,
.supports_autosuspend = 1,
};
/* --- low level module stuff --- */