[PATCH 2/5] mtd: nand: Propagate mtd_device_unregister() return value in tear down

[Richard Weinberger]

Boris,

Am 06.07.2016 um 15:34 schrieb Boris Brezillon:
>>  /**
>> - * nand_release - [NAND Interface] Free resources held by the NAND device
>> + * __nand_release - [NAND Interface] Free resources held by the NAND device
>>   * @mtd: MTD device structure
>>   */
>> -void nand_release(struct mtd_info *mtd)
>> +int __nand_release(struct mtd_info *mtd)
> 
> Can we find a better name? nand_release_safe()?

Sure. Let's pick nand_release_safe().

>>  {
>> +	int ret;
>>  	struct nand_chip *chip = mtd_to_nand(mtd);
>>  
>> +	ret = mtd_device_unregister(mtd);
>> +	if (ret)
>> +		return ret;
>> +
> 
> The question is, should we unregister the MTD device in nand_release().
> It feels a bit odd to have nand_scan_xxx() functions only doing the
> nand_chip initialization and letting the NAND controller driver
> register the MTD device, and have nand_release() unregister the MTD
> device for us.
> 
> Maybe we should export a nand_cleanup() function that would just
> release nand_chip resources and let NAND controller drivers that
> really care about mtd_device_unregister() return code call it
> themselves before calling nand_cleanup() (instead of calling
> nand_release()).

You mean renaming nand_release() to nand_cleanup() and the driver
has to issue mtd_device_unregister() itself before it is allowed to
do nand_cleanup(). Yes, that is also an option.
The only downside is that we have to touch a lot of drivers then.
But the conversion should be almost trivial.

Thanks,
//richard