[patch]autosuspend for cdc-acm

Hi,

this implements autosuspend for cdc-acm devices.

	Regards
		Oliver
Signed-off-by: Oliver Neukum <[email protected]>
-- 

--- a/drivers/usb/class/cdc-acm.c	2007-06-11 13:27:17.000000000 +0200
+++ b/drivers/usb/class/cdc-acm.c	2007-05-30 20:56:00.000000000 +0200
@@ -330,26 +330,26 @@ static void acm_read_bulk(struct urb *ur
 		return;
 
 	if (status)
-		dev_dbg(&acm->data->dev, "bulk rx status %d", status);
+		dev_dbg(&acm->data->dev, "bulk rx status %d\n", status);
 
 	buf = rcv->buffer;
 	buf->size = urb->actual_length;
 
+	spin_lock(&acm->read_lock);
 	if (likely(status == 0)) {
-		spin_lock(&acm->read_lock);
 		list_add_tail(&rcv->list, &acm->spare_read_urbs);
 		list_add_tail(&buf->list, &acm->filled_read_bufs);
-		spin_unlock(&acm->read_lock);
 	} else {
 		/* we drop the buffer due to an error */
-		spin_lock(&acm->read_lock);
 		list_add_tail(&rcv->list, &acm->spare_read_urbs);
 		list_add(&buf->list, &acm->spare_read_bufs);
-		spin_unlock(&acm->read_lock);
 		/* nevertheless the tasklet must be kicked unconditionally
 		so the queue cannot dry up */
 	}
-	tasklet_schedule(&acm->urb_task);
+
+	if (!acm->suspending)
+		tasklet_schedule(&acm->urb_task);
+	spin_unlock(&acm->read_lock);
 }
 
 static void acm_rx_tasklet(unsigned long _acm)
@@ -835,7 +835,7 @@ static int acm_probe (struct usb_interfa
 
 	if (!buflen) {
 		if (intf->cur_altsetting->endpoint->extralen && intf->cur_altsetting->endpoint->extra) {
-			dev_dbg(&intf->dev,"Seeking extra descriptors on endpoint");
+			dev_dbg(&intf->dev,"Seeking extra descriptors on endpoint\n");
 			buflen = intf->cur_altsetting->endpoint->extralen;
 			buffer = intf->cur_altsetting->endpoint->extra;
 		} else {
@@ -885,24 +885,24 @@ next_desc:
 
 	if (!union_header) {
 		if (call_interface_num > 0) {
-			dev_dbg(&intf->dev,"No union descriptor, using call management descriptor");
+			dev_dbg(&intf->dev,"No union descriptor, using call management descriptor\n");
 			data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = call_interface_num));
 			control_interface = intf;
 		} else {
-			dev_dbg(&intf->dev,"No union descriptor, giving up");
+			dev_dbg(&intf->dev,"No union descriptor, giving up\n");
 			return -ENODEV;
 		}
 	} else {
 		control_interface = usb_ifnum_to_if(usb_dev, union_header->bMasterInterface0);
 		data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = union_header->bSlaveInterface0));
 		if (!control_interface || !data_interface) {
-			dev_dbg(&intf->dev,"no interfaces");
+			dev_dbg(&intf->dev,"no interfaces\n");
 			return -ENODEV;
 		}
 	}
 	
 	if (data_interface_num != call_interface_num)
-		dev_dbg(&intf->dev,"Seperate call control interface. That is not fully supported.");
+		dev_dbg(&intf->dev,"Seperate call control interface. That is not fully supported.\n");
 
 skip_normal_probe:
 
@@ -910,7 +910,7 @@ skip_normal_probe:
 	if (data_interface->cur_altsetting->desc.bInterfaceClass != CDC_DATA_INTERFACE_TYPE) {
 		if (control_interface->cur_altsetting->desc.bInterfaceClass == CDC_DATA_INTERFACE_TYPE) {
 			struct usb_interface *t;
-			dev_dbg(&intf->dev,"Your device has switched interfaces.");
+			dev_dbg(&intf->dev,"Your device has switched interfaces.\n");
 
 			t = control_interface;
 			control_interface = data_interface;
@@ -921,7 +921,7 @@ skip_normal_probe:
 	}
 	
 	if (usb_interface_claimed(data_interface)) { /* valid in this context */
-		dev_dbg(&intf->dev,"The data interface isn't available");
+		dev_dbg(&intf->dev,"The data interface isn't available\n");
 		return -EBUSY;
 	}
 
@@ -938,7 +938,7 @@ skip_normal_probe:
 	if (!usb_endpoint_dir_in(epread)) {
 		/* descriptors are swapped */
 		struct usb_endpoint_descriptor *t;
-		dev_dbg(&intf->dev,"The data interface has switched endpoints");
+		dev_dbg(&intf->dev,"The data interface has switched endpoints\n");
 		
 		t = epread;
 		epread = epwrite;
@@ -1143,11 +1143,60 @@ static void acm_disconnect(struct usb_in
 	}
 
 	mutex_unlock(&open_mutex);
-
 	if (acm->tty)
 		tty_hangup(acm->tty);
 }
 
+static int acm_suspend (struct usb_interface *intf, pm_message_t message)
+{
+	struct acm *acm = usb_get_intfdata(intf);
+	int i;
+
+	if (acm->suspend_counter++) {
+		dev_dbg(&intf->dev, "Suspend on additional interface\n");
+		return 0;
+	}
+
+	spin_lock_irq(&acm->read_lock);
+	acm->suspending = 1;
+	spin_unlock_irq(&acm->read_lock);
+
+	tasklet_disable(&acm->urb_task);
+
+	usb_kill_urb(acm->ctrlurb);
+	usb_kill_urb(acm->writeurb);
+	for (i = 0; i < acm->rx_buflimit; i++)
+		usb_kill_urb(acm->ru[i].urb);
+
+	dev_dbg(&intf->dev, "suspension of ACM device.\n");
+	return 0;
+}
+
+static int acm_resume (struct usb_interface *intf)
+{
+	struct acm *acm = usb_get_intfdata(intf);
+
+	if (--acm->suspend_counter)
+		return 0;
+
+	spin_lock_irq(&acm->read_lock);
+	acm->suspending = 0;
+	spin_unlock_irq(&acm->read_lock);
+
+	if (!acm->used)
+		return 0;
+
+	if (usb_submit_urb(acm->ctrlurb, GFP_NOIO)) {
+		dev_dbg(&intf->dev, "cannot resume control urb");
+		return -EIO;
+	}
+
+	/* This restarts the read queue */
+	tasklet_schedule(&acm->urb_task);
+
+	return 0;
+}
+
 /*
  * USB driver structure.
  */
@@ -1197,6 +1246,8 @@ static struct usb_driver acm_driver = {
 	.name =		"cdc_acm",
 	.probe =	acm_probe,
 	.disconnect =	acm_disconnect,
+	.suspend =	acm_suspend,
+	.resume =	acm_resume,
 	.id_table =	acm_ids,
 };
 
--- a/drivers/usb/class/cdc-acm.h	2007-06-11 13:27:17.000000000 +0200
+++ b/drivers/usb/class/cdc-acm.h	2007-05-30 11:57:43.000000000 +0200
@@ -119,6 +119,8 @@ struct acm {
 	unsigned int minor;				/* acm minor number */
 	unsigned char throttle;				/* throttled by tty layer */
 	unsigned char clocal;				/* termios CLOCAL */
+	unsigned char suspend_counter;			/* count of suspended interfaces */
+	unsigned char suspending;			/* suspension is in progress */
 	unsigned int ctrl_caps;				/* control capabilities from the class specific header */
 };
 

-------------------------------------------------------------------------
This SF.net email is sponsored by DB2 Express
Download DB2 Express C - the FREE version of DB2 express and take
control of your XML. No limits. Just data. Click to get it now.
http://sourceforge.net/powerbar/db2/
_______________________________________________
[email protected]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-devel