diff options
Diffstat (limited to 'drivers/usb/misc/usblcd.c')
-rw-r--r-- | drivers/usb/misc/usblcd.c | 67 |
1 files changed, 47 insertions, 20 deletions
diff --git a/drivers/usb/misc/usblcd.c b/drivers/usb/misc/usblcd.c index 12bad8a205a7..504f7221b0d0 100644 --- a/drivers/usb/misc/usblcd.c +++ b/drivers/usb/misc/usblcd.c @@ -45,13 +45,13 @@ struct usb_lcd { struct kref kref; struct semaphore limit_sem; /* to stop writes at full throttle from * using up all RAM */ + struct usb_anchor submitted; /* URBs to wait for before suspend */ }; #define to_lcd_dev(d) container_of(d, struct usb_lcd, kref) #define USB_LCD_CONCURRENT_WRITES 5 static struct usb_driver lcd_driver; -static DEFINE_MUTEX(usb_lcd_open_mutex); static void lcd_delete(struct kref *kref) @@ -68,35 +68,35 @@ static int lcd_open(struct inode *inode, struct file *file) { struct usb_lcd *dev; struct usb_interface *interface; - int subminor; - int retval = 0; + int subminor, r; subminor = iminor(inode); - mutex_lock(&usb_lcd_open_mutex); interface = usb_find_interface(&lcd_driver, subminor); if (!interface) { err ("USBLCD: %s - error, can't find device for minor %d", __FUNCTION__, subminor); - retval = -ENODEV; - goto exit; + return -ENODEV; } dev = usb_get_intfdata(interface); - if (!dev) { - retval = -ENODEV; - goto exit; - } + if (!dev) + return -ENODEV; /* increment our usage count for the device */ kref_get(&dev->kref); + /* grab a power reference */ + r = usb_autopm_get_interface(interface); + if (r < 0) { + kref_put(&dev->kref, lcd_delete); + return r; + } + /* save our object in the file's private structure */ file->private_data = dev; -exit: - mutex_unlock(&usb_lcd_open_mutex); - return retval; + return 0; } static int lcd_release(struct inode *inode, struct file *file) @@ -108,6 +108,7 @@ static int lcd_release(struct inode *inode, struct file *file) return -ENODEV; /* decrement the count on our device */ + usb_autopm_put_interface(dev->interface); kref_put(&dev->kref, lcd_delete); return 0; } @@ -233,12 +234,14 @@ static ssize_t lcd_write(struct file *file, const char __user * user_buffer, siz usb_sndbulkpipe(dev->udev, dev->bulk_out_endpointAddr), buf, count, lcd_write_bulk_callback, dev); urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; + + usb_anchor_urb(urb, &dev->submitted); /* send the data out the bulk port */ retval = usb_submit_urb(urb, GFP_KERNEL); if (retval) { err("USBLCD: %s - failed submitting write urb, error %d", __FUNCTION__, retval); - goto error; + goto error_unanchor; } /* release our reference to this urb, the USB core will eventually free it entirely */ @@ -246,7 +249,8 @@ static ssize_t lcd_write(struct file *file, const char __user * user_buffer, siz exit: return count; - +error_unanchor: + usb_unanchor_urb(urb); error: usb_buffer_free(dev->udev, count, buf, urb->transfer_dma); usb_free_urb(urb); @@ -291,6 +295,7 @@ static int lcd_probe(struct usb_interface *interface, const struct usb_device_id } kref_init(&dev->kref); sema_init(&dev->limit_sem, USB_LCD_CONCURRENT_WRITES); + init_usb_anchor(&dev->submitted); dev->udev = usb_get_dev(interface_to_usbdev(interface)); dev->interface = interface; @@ -358,22 +363,41 @@ error: return retval; } +static void lcd_draw_down(struct usb_lcd *dev) +{ + int time; + + time = usb_wait_anchor_empty_timeout(&dev->submitted, 1000); + if (!time) + usb_kill_anchored_urbs(&dev->submitted); +} + +static int lcd_suspend(struct usb_interface *intf, pm_message_t message) +{ + struct usb_lcd *dev = usb_get_intfdata(intf); + + if (!dev) + return 0; + lcd_draw_down(dev); + return 0; +} + +static int lcd_resume (struct usb_interface *intf) +{ + return 0; +} + static void lcd_disconnect(struct usb_interface *interface) { struct usb_lcd *dev; int minor = interface->minor; - /* prevent skel_open() from racing skel_disconnect() */ - mutex_lock(&usb_lcd_open_mutex); - dev = usb_get_intfdata(interface); usb_set_intfdata(interface, NULL); /* give back our minor */ usb_deregister_dev(interface, &lcd_class); - mutex_unlock(&usb_lcd_open_mutex); - /* decrement our usage count */ kref_put(&dev->kref, lcd_delete); @@ -384,7 +408,10 @@ static struct usb_driver lcd_driver = { .name = "usblcd", .probe = lcd_probe, .disconnect = lcd_disconnect, + .suspend = lcd_suspend, + .resume = lcd_resume, .id_table = id_table, + .supports_autosuspend = 1, }; static int __init usb_lcd_init(void) |