[PATCH] UHCI: Don't store device pointer in QH or TD

This patch simplifies the uhci-hcd driver by removing the device pointer
currently stored in the QH and TD structures.  Those pointers weren't
being used for anything other than to increment the device's reference
count, which is unnecessary since the device is used only when an URB
completes, and outstanding URBs take their own reference to the device.
As a useful side effect, this change means that uhci-hcd no longer needs
to have the root-hub device available in the start routine.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/host/uhci-hcd.c

@@ -634,14 +634,14 @@ static int uhci_start(struct usb_hcd *hcd)
 		goto err_alloc_root_hub;
 	}
 
-	uhci->term_td = uhci_alloc_td(uhci, udev);
+	uhci->term_td = uhci_alloc_td(uhci);
 	if (!uhci->term_td) {
 		dev_err(uhci_dev(uhci), "unable to allocate terminating TD\n");
 		goto err_alloc_term_td;
 	}
 
 	for (i = 0; i < UHCI_NUM_SKELQH; i++) {
-		uhci->skelqh[i] = uhci_alloc_qh(uhci, udev);
+		uhci->skelqh[i] = uhci_alloc_qh(uhci);
 		if (!uhci->skelqh[i]) {
 			dev_err(uhci_dev(uhci), "unable to allocate QH\n");
 			goto err_alloc_skelqh;

drivers/usb/host/uhci-hcd.h

@@ -114,7 +114,6 @@ struct uhci_qh {
 	/* Software fields */
 	dma_addr_t dma_handle;
 
-	struct usb_device *dev;
 	struct urb_priv *urbp;
 
 	struct list_head list;		/* P: uhci->frame_list_lock */
@@ -206,7 +205,6 @@ struct uhci_td {
 	/* Software fields */
 	dma_addr_t dma_handle;
 
-	struct usb_device *dev;
 	struct urb *urb;
 
 	struct list_head list;		/* P: urb->lock */

drivers/usb/host/uhci-q.c

@@ -48,7 +48,7 @@ static inline void uhci_moveto_complete(struct uhci_hcd *uhci,
 	list_move_tail(&urbp->urb_list, &uhci->complete_list);
 }
 
-static struct uhci_td *uhci_alloc_td(struct uhci_hcd *uhci, struct usb_device *dev)
+static struct uhci_td *uhci_alloc_td(struct uhci_hcd *uhci)
 {
 	dma_addr_t dma_handle;
 	struct uhci_td *td;
@@ -63,14 +63,11 @@ static struct uhci_td *uhci_alloc_td(struct uhci_hcd *uhci, struct usb_device *d
 	td->buffer = 0;
 
 	td->frame = -1;
-	td->dev = dev;
 
 	INIT_LIST_HEAD(&td->list);
 	INIT_LIST_HEAD(&td->remove_list);
 	INIT_LIST_HEAD(&td->fl_list);
 
-	usb_get_dev(dev);
-
 	return td;
 }
 
@@ -170,13 +167,10 @@ static void uhci_free_td(struct uhci_hcd *uhci, struct uhci_td *td)
 	if (!list_empty(&td->fl_list))
 		dev_warn(uhci_dev(uhci), "td %p still in fl_list!\n", td);
 
-	if (td->dev)
-		usb_put_dev(td->dev);
-
 	dma_pool_free(uhci->td_pool, td, td->dma_handle);
 }
 
-static struct uhci_qh *uhci_alloc_qh(struct uhci_hcd *uhci, struct usb_device *dev)
+static struct uhci_qh *uhci_alloc_qh(struct uhci_hcd *uhci)
 {
 	dma_addr_t dma_handle;
 	struct uhci_qh *qh;
@@ -190,14 +184,11 @@ static struct uhci_qh *uhci_alloc_qh(struct uhci_hcd *uhci, struct usb_device *d
 	qh->element = UHCI_PTR_TERM;
 	qh->link = UHCI_PTR_TERM;
 
-	qh->dev = dev;
 	qh->urbp = NULL;
 
 	INIT_LIST_HEAD(&qh->list);
 	INIT_LIST_HEAD(&qh->remove_list);
 
-	usb_get_dev(dev);
-
 	return qh;
 }
 
@@ -208,9 +199,6 @@ static void uhci_free_qh(struct uhci_hcd *uhci, struct uhci_qh *qh)
 	if (!list_empty(&qh->remove_list))
 		dev_warn(uhci_dev(uhci), "qh %p still in remove_list!\n", qh);
 
-	if (qh->dev)
-		usb_put_dev(qh->dev);
-
 	dma_pool_free(uhci->qh_pool, qh, qh->dma_handle);
 }
 
@@ -599,7 +587,7 @@ static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb, struct ur
 	/*
 	 * Build the TD for the control request setup packet
 	 */
-	td = uhci_alloc_td(uhci, urb->dev);
+	td = uhci_alloc_td(uhci);
 	if (!td)
 		return -ENOMEM;
 
@@ -628,7 +616,7 @@ static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb, struct ur
 		if (pktsze > maxsze)
 			pktsze = maxsze;
 
-		td = uhci_alloc_td(uhci, urb->dev);
+		td = uhci_alloc_td(uhci);
 		if (!td)
 			return -ENOMEM;
 
@@ -646,7 +634,7 @@ static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb, struct ur
 	/*
 	 * Build the final TD for control status 
 	 */
-	td = uhci_alloc_td(uhci, urb->dev);
+	td = uhci_alloc_td(uhci);
 	if (!td)
 		return -ENOMEM;
 
@@ -668,7 +656,7 @@ static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb, struct ur
 	uhci_fill_td(td, status | TD_CTRL_IOC,
 		destination | uhci_explen(UHCI_NULL_DATA_SIZE), 0);
 
-	qh = uhci_alloc_qh(uhci, urb->dev);
+	qh = uhci_alloc_qh(uhci);
 	if (!qh)
 		return -ENOMEM;
 
@@ -867,7 +855,7 @@ static int uhci_submit_common(struct uhci_hcd *uhci, struct urb *urb, struct urb
 				status &= ~TD_CTRL_SPD;
 		}
 
-		td = uhci_alloc_td(uhci, urb->dev);
+		td = uhci_alloc_td(uhci);
 		if (!td)
 			return -ENOMEM;
 
@@ -893,7 +881,7 @@ static int uhci_submit_common(struct uhci_hcd *uhci, struct urb *urb, struct urb
 	 */
 	if (usb_pipeout(urb->pipe) && (urb->transfer_flags & URB_ZERO_PACKET) &&
 	    !len && urb->transfer_buffer_length) {
-		td = uhci_alloc_td(uhci, urb->dev);
+		td = uhci_alloc_td(uhci);
 		if (!td)
 			return -ENOMEM;
 
@@ -915,7 +903,7 @@ static int uhci_submit_common(struct uhci_hcd *uhci, struct urb *urb, struct urb
 	 * flag setting. */
 	td->status |= cpu_to_le32(TD_CTRL_IOC);
 
-	qh = uhci_alloc_qh(uhci, urb->dev);
+	qh = uhci_alloc_qh(uhci);
 	if (!qh)
 		return -ENOMEM;
 
@@ -1098,7 +1086,7 @@ static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb)
 		if (!urb->iso_frame_desc[i].length)
 			continue;
 
-		td = uhci_alloc_td(uhci, urb->dev);
+		td = uhci_alloc_td(uhci);
 		if (!td)
 			return -ENOMEM;