Re: [PATCH v3 2/2] mtd: rawnand: add hooks that may be called during nand_scan()

[Miquel Raynal <miquel.raynal@bootlin.com>]

Hi Boris, Stefan,

Boris Brezillon <boris.brezillon@bootlin.com> wrote on Fri, 27 Jul 2018
00:40:32 +0200:

> On Fri, 27 Jul 2018 00:20:50 +0200
> Stefan Agner <stefan@agner.ch> wrote:
> 
> > On 26.07.2018 20:12, Boris Brezillon wrote:  
> > > On Thu, 26 Jul 2018 18:22:10 +0200
> > > Stefan Agner <stefan@agner.ch> wrote:    
> > >> > +/**
> > >> > + * struct nand_controller_ops - Controller operations
> > >> > + *
> > >> > + * @attach_chip: Callback that will be called between nand_detect() and
> > >> > + *		 nand_scan_tail() during nand_scan() (optional).
> > >> > + * @detach_chip: Callback that will be called from nand_cleanup() or if
> > >> > + *		 nand_scan_tail() fails (optional).    
> > >>
> > >> This documentation reads not very helpful to me.
> > >>
> > >> It would be useful if it is written more from the driver developers
> > >> perspective, e.g. what those callbacks ideally are supposed to do...
> > >>    
> > > 
> > > Indeed. How about:
> > > 
> > > 	@attach_chip: this method is called between after the NAND    
> > 
> > I guess just after.  
> 
> Yep.
> 
> >   
> > > 		      detection phase to let controller driver
> > > 		      tweak/customize the configuration based on the
> > > 		      NAND properties (page size, OOB size, ECC
> > > 		      requirements, ...).    
> > 
> > Maybe explicitly state that NAND flash parameters are available in this
> > call, e.g.
> > 
> > 	@attach_chip: this method is called after the NAND detection 
> > 		      phase after flash ID and MTD fields such as
> > 		      erase size, page size and OOB size have been
> > 		      set up. ECC requirements are available if
> > 		      provided by the NAND chip or device tree.
> > 		      Typically used to chose the appropriate ECC  
> 
> 					^ choose
> 
> > 		      config and allocate associated resources.
> > 		      This hook is optional.
> >   
> 
> Sounds good.
> 
> >   
> > > 	@detach_chip: free all resources allocated/claimed in
> > > 		      nand_controller_ops->detach_chip().    
> > 
> > That probably should read nand_controller_ops->attach_chip().  
> 
> And yes, I meant attach_chip().
> 
> >   
> > > 		      This hook is optional.    

Maybe I've been a bit lazy on the documentation :)

Thanks Stefan for pointing it, I'll fix when applying with the above
proposal.

Miquèl