[PATCH] usb/gadget/snps_udc_core: Convert timers to use timer_setup()

[PATCH] usb/gadget/snps_udc_core: 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.

If the probe fails, udc_remove() will not be called, so there is no
reason to make del_timer_sync() calls conditional. As a result, use of
the .data field can be dropped, in support of making removing this field
entirely from struct timer_list.

Cc: Felipe Balbi <balbi@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Raviteja Garimella <raviteja.garimella@broadcom.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: "Gustavo A. R. Silva" <garsilva@embeddedor.com>
Cc: linux-usb@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 drivers/usb/gadget/udc/snps_udc_core.c | 19 ++++++-------------
 1 file changed, 6 insertions(+), 13 deletions(-)

diff --git a/drivers/usb/gadget/udc/snps_udc_core.c b/drivers/usb/gadget/udc/snps_udc_core.c
index 47df99dbaef4..2f5e788dd978 100644
--- a/drivers/usb/gadget/udc/snps_udc_core.c
+++ b/drivers/usb/gadget/udc/snps_udc_core.c
@@ -1733,7 +1733,7 @@ static void udc_soft_reset(struct udc *dev)
 }
 
 /* RDE timer callback to set RDE bit */
-static void udc_timer_function(unsigned long v)
+static void udc_timer_function(struct timer_list *unused)
 {
 	u32 tmp;
 
@@ -1813,7 +1813,7 @@ static void udc_handle_halt_state(struct udc_ep *ep)
 }
 
 /* Stall timer callback to poll S bit and set it again after */
-static void udc_pollstall_timer_function(unsigned long v)
+static void udc_pollstall_timer_function(struct timer_list *unused)
 {
 	struct udc_ep *ep;
 	int halted = 0;
@@ -3067,14 +3067,12 @@ void udc_remove(struct udc *dev)
 	stop_timer++;
 	if (timer_pending(&udc_timer))
 		wait_for_completion(&on_exit);
-	if (udc_timer.data)
-		del_timer_sync(&udc_timer);
+	del_timer_sync(&udc_timer);
 	/* remove pollstall timer */
 	stop_pollstall_timer++;
 	if (timer_pending(&udc_pollstall_timer))
 		wait_for_completion(&on_pollstall_exit);
-	if (udc_pollstall_timer.data)
-		del_timer_sync(&udc_pollstall_timer);
+	del_timer_sync(&udc_pollstall_timer);
 	udc = NULL;
 }
 EXPORT_SYMBOL_GPL(udc_remove);
@@ -3164,10 +3162,6 @@ int udc_probe(struct udc *dev)
 	u32		reg;
 	int		retval;
 
-	/* mark timer as not initialized */
-	udc_timer.data = 0;
-	udc_pollstall_timer.data = 0;
-
 	/* device struct setup */
 	dev->gadget.ops = &udc_ops;
 
@@ -3207,9 +3201,8 @@ int udc_probe(struct udc *dev)
 		goto finished;
 
 	/* timer init */
-	setup_timer(&udc_timer, udc_timer_function, 1);
-	/* timer pollstall init */
-	setup_timer(&udc_pollstall_timer, udc_pollstall_timer_function, 1);
+	timer_setup(&udc_timer, udc_timer_function, 0);
+	timer_setup(&udc_pollstall_timer, udc_pollstall_timer_function, 0);
 
 	/* set SD */
 	reg = readl(&dev->regs->ctl);
-- 
2.7.4


-- 
Kees Cook
Pixel Security

Re: [PATCH] usb/gadget/snps_udc_core: Convert timers to use timer_setup()

[Michal Nazarewicz]

On Mon, Oct 16 2017, Kees Cook wrote:
> 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.
>
> If the probe fails, udc_remove() will not be called, so there is no
> reason to make del_timer_sync() calls conditional. As a result, use of
> the .data field can be dropped, in support of making removing this field
> entirely from struct timer_list.
>
> Cc: Felipe Balbi <balbi@kernel.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Raviteja Garimella <raviteja.garimella@broadcom.com>
> Cc: Michal Nazarewicz <mina86@mina86.com>

Acked-by: Michal Nazarewicz <mina86@mina86.com>

> Cc: "Gustavo A. R. Silva" <garsilva@embeddedor.com>
> Cc: linux-usb@vger.kernel.org
> Signed-off-by: Kees Cook <keescook@chromium.org>
> ---
>  drivers/usb/gadget/udc/snps_udc_core.c | 19 ++++++-------------
>  1 file changed, 6 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/usb/gadget/udc/snps_udc_core.c b/drivers/usb/gadget/udc/snps_udc_core.c
> index 47df99dbaef4..2f5e788dd978 100644
> --- a/drivers/usb/gadget/udc/snps_udc_core.c
> +++ b/drivers/usb/gadget/udc/snps_udc_core.c
> @@ -1733,7 +1733,7 @@ static void udc_soft_reset(struct udc *dev)
>  }
>  
>  /* RDE timer callback to set RDE bit */
> -static void udc_timer_function(unsigned long v)
> +static void udc_timer_function(struct timer_list *unused)
>  {
>  	u32 tmp;
>  
> @@ -1813,7 +1813,7 @@ static void udc_handle_halt_state(struct udc_ep *ep)
>  }
>  
>  /* Stall timer callback to poll S bit and set it again after */
> -static void udc_pollstall_timer_function(unsigned long v)
> +static void udc_pollstall_timer_function(struct timer_list *unused)
>  {
>  	struct udc_ep *ep;
>  	int halted = 0;
> @@ -3067,14 +3067,12 @@ void udc_remove(struct udc *dev)
>  	stop_timer++;
>  	if (timer_pending(&udc_timer))
>  		wait_for_completion(&on_exit);
> -	if (udc_timer.data)
> -		del_timer_sync(&udc_timer);
> +	del_timer_sync(&udc_timer);
>  	/* remove pollstall timer */
>  	stop_pollstall_timer++;
>  	if (timer_pending(&udc_pollstall_timer))
>  		wait_for_completion(&on_pollstall_exit);
> -	if (udc_pollstall_timer.data)
> -		del_timer_sync(&udc_pollstall_timer);
> +	del_timer_sync(&udc_pollstall_timer);
>  	udc = NULL;
>  }
>  EXPORT_SYMBOL_GPL(udc_remove);
> @@ -3164,10 +3162,6 @@ int udc_probe(struct udc *dev)
>  	u32		reg;
>  	int		retval;
>  
> -	/* mark timer as not initialized */
> -	udc_timer.data = 0;
> -	udc_pollstall_timer.data = 0;
> -
>  	/* device struct setup */
>  	dev->gadget.ops = &udc_ops;
>  
> @@ -3207,9 +3201,8 @@ int udc_probe(struct udc *dev)
>  		goto finished;
>  
>  	/* timer init */
> -	setup_timer(&udc_timer, udc_timer_function, 1);
> -	/* timer pollstall init */
> -	setup_timer(&udc_pollstall_timer, udc_pollstall_timer_function, 1);
> +	timer_setup(&udc_timer, udc_timer_function, 0);
> +	timer_setup(&udc_pollstall_timer, udc_pollstall_timer_function, 0);
>  
>  	/* set SD */
>  	reg = readl(&dev->regs->ctl);
> -- 
> 2.7.4

-- 
Best regards
ミハウ “𝓶𝓲𝓷𝓪86” ナザレヴイツ
«If at first you don’t succeed, give up skydiving»