staging: comedi: USB devs not working / some comedi core reorganization

Bernd Porr mail at berndporr.me.uk
Tue Dec 10 23:28:46 UTC 2013


Agree with your comments. Let's just do the

return ret < 0 ? ret : 0;

and it's sorted. Thanks for the quick reply.

/Bernd

On 10/12/13 23:24, Hartley Sweeten wrote:
> On Tuesday, December 10, 2013 3:28 PM, Dan Carpenter wrote:
>> On Tue, Dec 10, 2013 at 09:30:43PM +0000, Ian Abbott wrote:
>>>
>>> It might be better just to prevent comedi_load_firmware() returning
>>> a value greater than zero, since I can't think of any reason why it
>>> would need to.  That would also work for the usbdux driver.
>>>
>>
>> Yeah.  It looks like it's usbduxfast_upload_firmware() which has the
>   >problem.  Does this fix your problem?  This bug was introduced in
>> 161f440c8d91 ('staging: comedi: drivers: usbduxfast.c: fix for DMA
>> buffers on stack')
>
> Actually I think I broke it when I introduced the comedi_upload_firmware()
> helper and converted the usbdux drivers to use it.
>
>> diff --git a/drivers/staging/comedi/drivers/usbduxfast.c b/drivers/staging/comedi/drivers/usbduxfast.c
>> index 9707dd1239c4..f2d8d7fb7aab 100644
>> --- a/drivers/staging/comedi/drivers/usbduxfast.c
>> +++ b/drivers/staging/comedi/drivers/usbduxfast.c
>> @@ -1040,6 +1040,7 @@ static int usbduxfast_upload_firmware(struct comedi_device *dev,
>>   			      EZTIMEOUT);
>>   	if (ret < 0)
>>   		dev_err(dev->class_dev, "can not start firmware\n");
>> +	ret = 0;
>>
>>   done:
>>   	kfree(tmp);
>
> This would only fix the usbduxfast driver.
>
> I think Ian's comment about fixing comedi_load_firmware() is the correct
> one.  This should do it:
>
>
>  From dcb9cae663fb7489e235569de20ac5757450953d Mon Sep 17 00:00:00 2001
> From: H Hartley Sweeten <hsweeten at visionengravers.com>
> Date: Tue, 18 Jun 2013 13:21:13 -0700
> Subject: [PATCH] staging: comedi: drivers: fix return value of
>   comedi_load_firmware()
>
> Some of the callback functions that upload the firmware in the comedi
> drivers return a positive value indicating the number of bytes sent
> to the device. Detect this condition and just return '0' to indicate
> a successful upload.
>
> Signed-off-by: H Hartley Sweeten <hsweeten at visionengravers.com>
> Cc: Ian Abbott <abbotti at mev.co.uk>
> Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
> Cc: Bernd Porr <mail at berndporr.me.uk>
> Cc: Dan Carpenter <dan.carpenter at oracle.com>
> ---
>   drivers/staging/comedi/drivers.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/staging/comedi/drivers.c b/drivers/staging/comedi/drivers.c
> index a5d03b9..9d71b4d 100644
> --- a/drivers/staging/comedi/drivers.c
> +++ b/drivers/staging/comedi/drivers.c
> @@ -451,7 +451,7 @@ int comedi_load_firmware(struct comedi_device *dev,
>   		release_firmware(fw);
>   	}
>
> -	return ret;
> +	return ret < 0 ? ret : 0;
>   }
>   EXPORT_SYMBOL_GPL(comedi_load_firmware);
>
>

-- 
www:    http://www.berndporr.me.uk/
         http://www.linux-usb-daq.co.uk/
	http://www.imdb.com/name/nm3293421/
Mobile: +44 (0)7840 340069
Work:   +44 (0)141 330 5237
         University of Glasgow
         School of Engineering
         Rankine Building, Oakfield Avenue,
         Glasgow, G12 8LT


More information about the devel mailing list