linux-kernel - [PATCH 16/26] usb: gadget: f_rndis: eliminate abuse of ep->driver data

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Message-id: <1442327229-28320-17-git-send-email-r.baldyga@samsung.com>
Date:	Tue, 15 Sep 2015 16:26:59 +0200
From:	Robert Baldyga <r.baldyga@...sung.com>
To:	balbi@...com
Cc:	gregkh@...uxfoundation.org, linux-usb@...r.kernel.org,
	linux-kernel@...r.kernel.org, b.zolnierkie@...sung.com,
	m.szyprowski@...sung.com, andrzej.p@...sung.com,
	Robert Baldyga <r.baldyga@...sung.com>
Subject: [PATCH 16/26] usb: gadget: f_rndis: eliminate abuse of ep->driver data

Since ep->driver_data is not used for endpoint claiming, neither for
enabled/disabled state storing, we can reduce number of places where
we read or modify it's value, as now it has no particular meaning for
function or framework logic.

In case of f_rndis, ep->driver_data was used only for endpoint claiming
and marking endpoints as enabled, so we can simplify code by reducing
it.

Signed-off-by: Robert Baldyga <r.baldyga@...sung.com>
---
 drivers/usb/gadget/function/f_rndis.c | 24 +++++-------------------
 1 file changed, 5 insertions(+), 19 deletions(-)

diff --git a/drivers/usb/gadget/function/f_rndis.c b/drivers/usb/gadget/function/f_rndis.c
index 32985da..fd301ed 100644
--- a/drivers/usb/gadget/function/f_rndis.c
+++ b/drivers/usb/gadget/function/f_rndis.c
@@ -543,22 +543,20 @@ static int rndis_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 	/* we know alt == 0 */
 
 	if (intf == rndis->ctrl_id) {
-		if (rndis->notify->driver_data) {
-			VDBG(cdev, "reset rndis control %d\n", intf);
-			usb_ep_disable(rndis->notify);
-		}
+		VDBG(cdev, "reset rndis control %d\n", intf);
+		usb_ep_disable(rndis->notify);
+
 		if (!rndis->notify->desc) {
 			VDBG(cdev, "init rndis ctrl %d\n", intf);
 			if (config_ep_by_speed(cdev->gadget, f, rndis->notify))
 				goto fail;
 		}
 		usb_ep_enable(rndis->notify);
-		rndis->notify->driver_data = rndis;
 
 	} else if (intf == rndis->data_id) {
 		struct net_device	*net;
 
-		if (rndis->port.in_ep->driver_data) {
+		if (rndis->port.in_ep->enabled) {
 			DBG(cdev, "reset rndis\n");
 			gether_disconnect(&rndis->port);
 		}
@@ -612,7 +610,7 @@ static void rndis_disable(struct usb_function *f)
 	struct f_rndis		*rndis = func_to_rndis(f);
 	struct usb_composite_dev *cdev = f->config->cdev;
 
-	if (!rndis->notify->driver_data)
+	if (!rndis->notify->enabled)
 		return;
 
 	DBG(cdev, "rndis deactivated\n");
@@ -621,7 +619,6 @@ static void rndis_disable(struct usb_function *f)
 	gether_disconnect(&rndis->port);
 
 	usb_ep_disable(rndis->notify);
-	rndis->notify->driver_data = NULL;
 }
 
 /*-------------------------------------------------------------------------*/
@@ -745,13 +742,11 @@ rndis_bind(struct usb_configuration *c, struct usb_function *f)
 	if (!ep)
 		goto fail;
 	rndis->port.in_ep = ep;
-	ep->driver_data = cdev;	/* claim */
 
 	ep = usb_ep_autoconfig(cdev->gadget, &fs_out_desc);
 	if (!ep)
 		goto fail;
 	rndis->port.out_ep = ep;
-	ep->driver_data = cdev;	/* claim */
 
 	/* NOTE:  a status/notification endpoint is, strictly speaking,
 	 * optional.  We don't treat it that way though!  It's simpler,
@@ -761,7 +756,6 @@ rndis_bind(struct usb_configuration *c, struct usb_function *f)
 	if (!ep)
 		goto fail;
 	rndis->notify = ep;
-	ep->driver_data = cdev;	/* claim */
 
 	status = -ENOMEM;
 
@@ -829,14 +823,6 @@ fail:
 		usb_ep_free_request(rndis->notify, rndis->notify_req);
 	}
 
-	/* we might as well release our claims on endpoints */
-	if (rndis->notify)
-		rndis->notify->driver_data = NULL;
-	if (rndis->port.out_ep)
-		rndis->port.out_ep->driver_data = NULL;
-	if (rndis->port.in_ep)
-		rndis->port.in_ep->driver_data = NULL;
-
 	ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
 
 	return status;
-- 
1.9.1

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