Re: [PATCH] auxdisplay: Convert timers to use timer_setup()

[Paul Burton]

Hi Kees,

On Wed, Oct 25, 2017 at 03:22:57AM -0700, 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.

For the whole patch:

  Reviewed-by: Paul Burton <paul.burton@xxxxxxxx>

For the img-ascii-lcd part:

  Tested-by: Paul Burton <paul.burton@xxxxxxxx>

Thanks,
    Paul

> Cc: Paul Burton <paul.burton@xxxxxxxxxx>
> Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@xxxxxxxxx>
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
> ---
>  drivers/auxdisplay/img-ascii-lcd.c | 10 ++++------
>  drivers/auxdisplay/panel.c         |  4 ++--
>  2 files changed, 6 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/auxdisplay/img-ascii-lcd.c b/drivers/auxdisplay/img-ascii-lcd.c
> index 25306fa27251..c9e32d29ec81 100644
> --- a/drivers/auxdisplay/img-ascii-lcd.c
> +++ b/drivers/auxdisplay/img-ascii-lcd.c
> @@ -229,9 +229,9 @@ MODULE_DEVICE_TABLE(of, img_ascii_lcd_matches);
>   * Scroll the current message along the LCD by one character, rearming the
>   * timer if required.
>   */
> -static void img_ascii_lcd_scroll(unsigned long arg)
> +static void img_ascii_lcd_scroll(struct timer_list *t)
>  {
> -	struct img_ascii_lcd_ctx *ctx = (struct img_ascii_lcd_ctx *)arg;
> +	struct img_ascii_lcd_ctx *ctx = from_timer(ctx, t, timer);
>  	unsigned int i, ch = ctx->scroll_pos;
>  	unsigned int num_chars = ctx->cfg->num_chars;
>  
> @@ -299,7 +299,7 @@ static int img_ascii_lcd_display(struct img_ascii_lcd_ctx *ctx,
>  	ctx->scroll_pos = 0;
>  
>  	/* update the LCD */
> -	img_ascii_lcd_scroll((unsigned long)ctx);
> +	img_ascii_lcd_scroll(&ctx->timer);
>  
>  	return 0;
>  }
> @@ -395,9 +395,7 @@ static int img_ascii_lcd_probe(struct platform_device *pdev)
>  	ctx->scroll_rate = HZ / 2;
>  
>  	/* initialise a timer for scrolling the message */
> -	init_timer(&ctx->timer);
> -	ctx->timer.function = img_ascii_lcd_scroll;
> -	ctx->timer.data = (unsigned long)ctx;
> +	timer_setup(&ctx->timer, img_ascii_lcd_scroll, 0);
>  
>  	platform_set_drvdata(pdev, ctx);
>  
> diff --git a/drivers/auxdisplay/panel.c b/drivers/auxdisplay/panel.c
> index 6911acd896d9..ea7869c0d7f9 100644
> --- a/drivers/auxdisplay/panel.c
> +++ b/drivers/auxdisplay/panel.c
> @@ -1396,7 +1396,7 @@ static void panel_process_inputs(void)
>  	}
>  }
>  
> -static void panel_scan_timer(void)
> +static void panel_scan_timer(struct timer_list *unused)
>  {
>  	if (keypad.enabled && keypad_initialized) {
>  		if (spin_trylock_irq(&pprt_lock)) {
> @@ -1421,7 +1421,7 @@ static void init_scan_timer(void)
>  	if (scan_timer.function)
>  		return;		/* already started */
>  
> -	setup_timer(&scan_timer, (void *)&panel_scan_timer, 0);
> +	timer_setup(&scan_timer, panel_scan_timer, 0);
>  	scan_timer.expires = jiffies + INPUT_POLL_TIME;
>  	add_timer(&scan_timer);
>  }
> -- 
> 2.7.4
> 
> 
> -- 
> Kees Cook
> Pixel Security