Re: [PATCH] drivers/usb/gadget: Use ERR_PTR/IS_ERR

[David Brownell <david-b@pacbell.net>]

On Wednesday 09 December 2009, Julia Lawall wrote:
> From: Julia Lawall <julia@diku.dk>
> 
> Use ERR_PTR and IS_ERR rather than mixing integers and pointers.
> 
> The semantic match that finds this problem is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @@
> expression *E;
> @@
> 
> * E < 0
> // </smpl>
> 
> Signed-off-by: Julia Lawall <julia@diku.dk>

Acked-by: David Brownell <dbrownell@users.sourceforge.net>

> 
> ---
>  drivers/usb/gadget/f_audio.c        |    8 +++++---
>  1 files changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/usb/gadget/f_audio.c b/drivers/usb/gadget/f_audio.c
> index c43c89f..0f2eee1 100644
> --- a/drivers/usb/gadget/f_audio.c
> +++ b/drivers/usb/gadget/f_audio.c
> @@ -252,12 +252,12 @@ static struct f_audio_buf *f_audio_buffer_alloc(int buf_size)
>  
>  	copy_buf = kzalloc(sizeof *copy_buf, GFP_ATOMIC);
>  	if (!copy_buf)
> -		return (struct f_audio_buf *)-ENOMEM;
> +		return ERR_PTR(-ENOMEM);
>  
>  	copy_buf->buf = kzalloc(buf_size, GFP_ATOMIC);
>  	if (!copy_buf->buf) {
>  		kfree(copy_buf);
> -		return (struct f_audio_buf *)-ENOMEM;
> +		return ERR_PTR(-ENOMEM);
>  	}
>  
>  	return copy_buf;
> @@ -332,7 +332,7 @@ static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req)
>  		list_add_tail(&copy_buf->list, &audio->play_queue);
>  		schedule_work(&audio->playback_work);
>  		copy_buf = f_audio_buffer_alloc(audio_buf_size);
> -		if (copy_buf < 0)
> +		if (IS_ERR(copy_buf))
>  			return -ENOMEM;
>  	}
>  
> @@ -576,6 +576,8 @@ static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
>  			usb_ep_enable(out_ep, audio->out_desc);
>  			out_ep->driver_data = audio;
>  			audio->copy_buf = f_audio_buffer_alloc(audio_buf_size);
> +			if (IS_ERR(audio->copy_buf))
> +				return -ENOMEM;
>  
>  			/*
>  			 * allocate a bunch of read buffers
> 
>