X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fusb%2Fmisc%2Fusblcd.c;h=2db4228fbb016bce9548e899bad64a17dc428f7e;hb=8eb88c80d444fd249edaa7d895666cde79e7b3b8;hp=ada2ebc464ae2bd0eb9bdd5a03e1424caad3c42d;hpb=946b92437e550d6ed80213bf54a1f383e141aede;p=linux-2.6-omap-h63xx.git diff --git a/drivers/usb/misc/usblcd.c b/drivers/usb/misc/usblcd.c index ada2ebc464a..2db4228fbb0 100644 --- a/drivers/usb/misc/usblcd.c +++ b/drivers/usb/misc/usblcd.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -34,6 +35,8 @@ static struct usb_device_id id_table [] = { }; MODULE_DEVICE_TABLE (usb, id_table); +static DEFINE_MUTEX(open_disc_mutex); + struct usb_lcd { struct usb_device * udev; /* init: probe_lcd */ @@ -42,10 +45,15 @@ struct usb_lcd { size_t bulk_in_size; /* the size of the receive buffer */ __u8 bulk_in_endpointAddr; /* the address of the bulk in endpoint */ __u8 bulk_out_endpointAddr; /* the address of the bulk out endpoint */ - struct kref kref; + 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; @@ -63,33 +71,39 @@ 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); 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; + __func__, subminor); + return -ENODEV; } + mutex_lock(&open_disc_mutex); dev = usb_get_intfdata(interface); if (!dev) { - retval = -ENODEV; - goto exit; + mutex_unlock(&open_disc_mutex); + return -ENODEV; } /* increment our usage count for the device */ kref_get(&dev->kref); + mutex_unlock(&open_disc_mutex); + + /* 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: - return retval; + return 0; } static int lcd_release(struct inode *inode, struct file *file) @@ -101,6 +115,7 @@ 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; } @@ -131,7 +146,7 @@ static ssize_t lcd_read(struct file *file, char __user * buffer, size_t count, l return retval; } -static int lcd_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) +static long lcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct usb_lcd *dev; u16 bcdDevice; @@ -143,12 +158,14 @@ static int lcd_ioctl(struct inode *inode, struct file *file, unsigned int cmd, u switch (cmd) { case IOCTL_GET_HARD_VERSION: + lock_kernel(); bcdDevice = le16_to_cpu((dev->udev)->descriptor.bcdDevice); sprintf(buf,"%1d%1d.%1d%1d", (bcdDevice & 0xF000)>>12, (bcdDevice & 0xF00)>>8, (bcdDevice & 0xF0)>>4, (bcdDevice & 0xF)); + unlock_kernel(); if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0) return -EFAULT; break; @@ -168,27 +185,29 @@ static int lcd_ioctl(struct inode *inode, struct file *file, unsigned int cmd, u static void lcd_write_bulk_callback(struct urb *urb) { struct usb_lcd *dev; + int status = urb->status; - dev = (struct usb_lcd *)urb->context; + dev = urb->context; /* sync/async unlink faults aren't errors */ - if (urb->status && - !(urb->status == -ENOENT || - urb->status == -ECONNRESET || - urb->status == -ESHUTDOWN)) { + if (status && + !(status == -ENOENT || + status == -ECONNRESET || + status == -ESHUTDOWN)) { dbg("USBLCD: %s - nonzero write bulk status received: %d", - __FUNCTION__, urb->status); + __func__, status); } /* free up our allocated buffer */ usb_buffer_free(urb->dev, urb->transfer_buffer_length, urb->transfer_buffer, urb->transfer_dma); + up(&dev->limit_sem); } static ssize_t lcd_write(struct file *file, const char __user * user_buffer, size_t count, loff_t *ppos) { struct usb_lcd *dev; - int retval = 0; + int retval = 0, r; struct urb *urb = NULL; char *buf = NULL; @@ -198,10 +217,16 @@ static ssize_t lcd_write(struct file *file, const char __user * user_buffer, siz if (count == 0) goto exit; + r = down_interruptible(&dev->limit_sem); + if (r < 0) + return -EINTR; + /* create a urb, and a buffer for it, and copy the data to the urb */ urb = usb_alloc_urb(0, GFP_KERNEL); - if (!urb) - return -ENOMEM; + if (!urb) { + retval = -ENOMEM; + goto err_no_buf; + } buf = usb_buffer_alloc(dev->udev, count, GFP_KERNEL, &urb->transfer_dma); if (!buf) { @@ -219,12 +244,14 @@ 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; + err("USBLCD: %s - failed submitting write urb, error %d", __func__, retval); + goto error_unanchor; } /* release our reference to this urb, the USB core will eventually free it entirely */ @@ -232,10 +259,13 @@ 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); +err_no_buf: + up(&dev->limit_sem); return retval; } @@ -244,7 +274,7 @@ static const struct file_operations lcd_fops = { .read = lcd_read, .write = lcd_write, .open = lcd_open, - .ioctl = lcd_ioctl, + .unlocked_ioctl = lcd_ioctl, .release = lcd_release, }; @@ -274,6 +304,8 @@ static int lcd_probe(struct usb_interface *interface, const struct usb_device_id goto error; } 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; @@ -341,22 +373,43 @@ 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() */ - lock_kernel(); - + mutex_lock(&open_disc_mutex); dev = usb_get_intfdata(interface); usb_set_intfdata(interface, NULL); + mutex_unlock(&open_disc_mutex); /* give back our minor */ usb_deregister_dev(interface, &lcd_class); - unlock_kernel(); - /* decrement our usage count */ kref_put(&dev->kref, lcd_delete); @@ -367,7 +420,10 @@ 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)