[PATCH 2/3 v3] P4080/mtd: Only make elbc nand driver detect nand flash partitions

Scott Wood scottwood at freescale.com
Thu Sep 16 12:53:12 EDT 2010

On Thu, 16 Sep 2010 20:40:44 +0400
Anton Vorontsov <cbouatmailru at gmail.com> wrote:

> On Thu, Sep 16, 2010 at 11:14:48AM -0500, Scott Wood wrote:
> > > > DEFINE_MUTEX(fsl_elbc_mutex);
> > > 
> > > I'd place the mutex inside the fsl_lbc_ctrl_dev,
> > > i.e. fsl_lbc_ctrl_dev->nand_lock. This is to avoid more
> > > global variables.
> > 
> > I wouldn't.  If the lock is only meaningful to the NAND driver, it
> > should be declared in the NAND driver.
> > 
> > Besides, it's not any less of a global just because it's sitting inside
> > a singleton struct.
> > 
> > Perhaps it should be declared as a static local inside the probe
> > function, if it's just to guard against this one race.
> OK, in that case better be persistent and not introduce
> fsl_lbc_ctrl_dev->nand at all, as it isn't used outside
> of the driver.

We could, though it would be a step further away from being able to
support multiple controllers if that ever does happen.  Whereas sharing
a mutex between multiple controllers isn't a problem (it's just init,
not a performance-sensitive path where fine-grained locking is

> Having fsl_lbc_ctrl_dev->nand and its lock elsewhere in
> the code makes no sense.

That depends on whether you see it as that field's lock or as the init
code's lock, I guess.

It's not that big of a deal either way.


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