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Date: Tue, 26 Apr 2016 09:13:27 +0200
From: Sascha Hauer <s.hauer@pengutronix.de>
To: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Richard Weinberger <richard@nod.at>, linux-mtd@lists.infradead.org,
 kernel@pengutronix.de, Daniel Walter <dwalter@sigma-star.at>
Subject: Re: Pass -EUCLEAN to userspace?
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Fixed typo in subject, maybe this helps finding this thread in the
archives.

On Mon, Apr 25, 2016 at 04:11:44PM +0200, Boris Brezillon wrote:
> On Mon, 25 Apr 2016 11:26:16 +0200
> Boris Brezillon <boris.brezillon@free-electrons.com> wrote:
> 
> > > > 
> > > > Regarding the maximum number of bitflips per chunk, maybe we can make it
> > > > part of the ioctl request instead of saving the statistics at the MTD
> > > > level.
> > > > 
> > > > How about creating a new ioctl taking a pointer to this struct as a
> > > > parameter:
> > > > 
> > > > struct mtd_extended_read_ops {
> > > > 	/* Existing params */
> > > > 	unsigned int mode;
> > > > 	size_t len;
> > > > 	size_t retlen;
> > > > 	size_t ooblen;
> > > > 	size_t oobretlen;
> > > > 	uint32_t ooboffs;
> > > > 	void *datbuf;
> > > > 	void *oobbuf;
> > > > 
> > > > 	/*
> > > > 	 * Param containing the maximum number of bitflips for this
> > > > 	 * read request.
> > > > 	 */
> > > > 	unsigned int max_bitflips;
> > > > };    
> > > 
> > > Not sure how this ioctl exactly should look like, but this would solve
> > > the problem.  
> > 
> > Let me design a quick prototype, I'll let you follow up with the patch
> > submission process...
> 
> Below is an untested patch adding a new ioctl returning the ECC/read stats.
> Feel free to debug/enhance this implementation and submit it to the MTD
> ML.

Thanks Boris, I'll give it a try.

Sascha

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