[PATCH] usb: r8a66597-hcd: Convert timers to use timer_setup()

[Kees Cook]

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly. This rearranges the arrays of timers
to minimize the need for a pointer back to the main structure.

Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Chris Brandt <chris.brandt@xxxxxxxxxxx>
Cc: Julia Lawall <Julia.Lawall@xxxxxxx>
Cc: linux-usb@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
 drivers/usb/host/r8a66597-hcd.c | 27 ++++++++++++++-------------
 drivers/usb/host/r8a66597.h     | 11 +++++++++--
 2 files changed, 23 insertions(+), 15 deletions(-)

diff --git a/drivers/usb/host/r8a66597-hcd.c b/drivers/usb/host/r8a66597-hcd.c
index 5e5fc9d7d533..0f3d2aedaec5 100644
--- a/drivers/usb/host/r8a66597-hcd.c
+++ b/drivers/usb/host/r8a66597-hcd.c
@@ -1273,7 +1273,7 @@ static void set_td_timer(struct r8a66597 *r8a66597, struct r8a66597_td *td)
 			break;
 		}
 
-		mod_timer(&r8a66597->td_timer[td->pipenum],
+		mod_timer(&r8a66597->timers[td->pipenum].td,
 			  jiffies + msecs_to_jiffies(time));
 	}
 }
@@ -1733,9 +1733,10 @@ static void r8a66597_root_hub_control(struct r8a66597 *r8a66597, int port)
 	}
 }
 
-static void r8a66597_interval_timer(unsigned long _r8a66597)
+static void r8a66597_interval_timer(struct timer_list *t)
 {
-	struct r8a66597 *r8a66597 = (struct r8a66597 *)_r8a66597;
+	struct r8a66597_timers *timers = from_timer(timers, t, interval);
+	struct r8a66597 *r8a66597 = timers->r8a66597;
 	unsigned long flags;
 	u16 pipenum;
 	struct r8a66597_td *td;
@@ -1745,7 +1746,7 @@ static void r8a66597_interval_timer(unsigned long _r8a66597)
 	for (pipenum = 0; pipenum < R8A66597_MAX_NUM_PIPE; pipenum++) {
 		if (!(r8a66597->interval_map & (1 << pipenum)))
 			continue;
-		if (timer_pending(&r8a66597->interval_timer[pipenum]))
+		if (timer_pending(&r8a66597->timers[pipenum].interval))
 			continue;
 
 		td = r8a66597_get_td(r8a66597, pipenum);
@@ -1756,9 +1757,10 @@ static void r8a66597_interval_timer(unsigned long _r8a66597)
 	spin_unlock_irqrestore(&r8a66597->lock, flags);
 }
 
-static void r8a66597_td_timer(unsigned long _r8a66597)
+static void r8a66597_td_timer(struct timer_list *t)
 {
-	struct r8a66597 *r8a66597 = (struct r8a66597 *)_r8a66597;
+	struct r8a66597_timers *timers = from_timer(timers, t, td);
+	struct r8a66597 *r8a66597 = timers->r8a66597;
 	unsigned long flags;
 	u16 pipenum;
 	struct r8a66597_td *td, *new_td = NULL;
@@ -1768,7 +1770,7 @@ static void r8a66597_td_timer(unsigned long _r8a66597)
 	for (pipenum = 0; pipenum < R8A66597_MAX_NUM_PIPE; pipenum++) {
 		if (!(r8a66597->timeout_map & (1 << pipenum)))
 			continue;
-		if (timer_pending(&r8a66597->td_timer[pipenum]))
+		if (timer_pending(&r8a66597->timers[pipenum].td))
 			continue;
 
 		td = r8a66597_get_td(r8a66597, pipenum);
@@ -1942,7 +1944,7 @@ static int r8a66597_urb_enqueue(struct usb_hcd *hcd,
 	if (request) {
 		if (td->pipe->info.timer_interval) {
 			r8a66597->interval_map |= 1 << td->pipenum;
-			mod_timer(&r8a66597->interval_timer[td->pipenum],
+			mod_timer(&r8a66597->timers[td->pipenum].interval,
 				  jiffies + msecs_to_jiffies(
 					td->pipe->info.timer_interval));
 		} else {
@@ -2495,11 +2497,10 @@ static int r8a66597_probe(struct platform_device *pdev)
 
 	for (i = 0; i < R8A66597_MAX_NUM_PIPE; i++) {
 		INIT_LIST_HEAD(&r8a66597->pipe_queue[i]);
-		setup_timer(&r8a66597->td_timer[i], r8a66597_td_timer,
-			    (unsigned long)r8a66597);
-		setup_timer(&r8a66597->interval_timer[i],
-				r8a66597_interval_timer,
-				(unsigned long)r8a66597);
+		r8a66597->timers[i].r8a66597 = r8a66597;
+		timer_setup(&r8a66597->timers[i].td, r8a66597_td_timer, 0);
+		timer_setup(&r8a66597->timers[i].interval,
+			    r8a66597_interval_timer, 0);
 	}
 	INIT_LIST_HEAD(&r8a66597->child_device);
 
diff --git a/drivers/usb/host/r8a66597.h b/drivers/usb/host/r8a66597.h
index 672cea307abb..b8406c07f363 100644
--- a/drivers/usb/host/r8a66597.h
+++ b/drivers/usb/host/r8a66597.h
@@ -107,6 +107,14 @@ struct r8a66597_root_hub {
 	struct r8a66597_device	*dev;
 };
 
+struct r8a66597;
+
+struct r8a66597_timers {
+	struct timer_list td;
+	struct timer_list interval;
+	struct r8a66597 *r8a66597;
+};
+
 struct r8a66597 {
 	spinlock_t lock;
 	void __iomem *reg;
@@ -117,8 +125,7 @@ struct r8a66597 {
 	struct list_head		pipe_queue[R8A66597_MAX_NUM_PIPE];
 
 	struct timer_list rh_timer;
-	struct timer_list td_timer[R8A66597_MAX_NUM_PIPE];
-	struct timer_list interval_timer[R8A66597_MAX_NUM_PIPE];
+	struct r8a66597_timers timers[R8A66597_MAX_NUM_PIPE];
 
 	unsigned short address_map;
 	unsigned short timeout_map;
-- 
2.7.4


-- 
Kees Cook
Pixel Security