Re: [PATCH] zd1211rw: Use DMA-aware buffer for usb transfer

[Michael Buesch <mb@bu3sch.de>]

On Thursday 15 May 2008 17:12:15 Atsushi Nemoto wrote:
> @@ -312,22 +313,29 @@ int zd_usb_read_fw(struct zd_usb *usb, zd_addr_t addr, u8 *data, u16 len)
>  {
>  	int r;
>  	struct usb_device *udev = zd_usb_to_usbdev(usb);
> +	u8 *buf = kmalloc(len, GFP_KERNEL);
>  
> +	if (!buf)
> +		return -ENOMEM;

Not that my opinion counts here, but I don't like the coding style of
doing work in the variable definition block.
Pointer assignments in there are OK (like the zd_usb_to_usbdev, which just
fetches a pointer), but a kmalloc() call is IMO very confusing.

But the decision whether this is OK or not is not up to me.

>  	r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
>  		USB_REQ_FIRMWARE_READ_DATA, USB_DIR_IN | 0x40, addr, 0,
> -		data, len, 5000);
> +		buf, len, 5000);
>  	if (r < 0) {
>  		dev_err(&udev->dev,
>  			"read over firmware interface failed: %d\n", r);
> -		return r;
> +		goto exit;
>  	} else if (r != len) {
>  		dev_err(&udev->dev,
>  			"incomplete read over firmware interface: %d/%d\n",
>  			r, len);
> -		return -EIO;
> +		r = -EIO;
> +		goto exit;
>  	}
> -
> -	return 0;
> +	r = 0;
> +	memcpy(data, buf, len);
> +exit:
> +	kfree(buf);
> +	return r;
>  }


-- 
Greetings Michael.