Date: Mon, 12 Dec 2016 18:00:21 +0100
From: Boris Brezillon <boris.brezillon@free-electrons.com>
To: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: arvind Yadav <arvind.yadav.cs@gmail.com>, dwmw2@infradead.org,
        computersforpeace@gmail.com, marek.vasut@gmail.com, richard@nod.at,
        cyrille.pitchen@atmel.com, linux-mtd@lists.infradead.org,
        linux-kernel@vger.kernel.org
Subject: Re: [V2] mtd: devices: docg3:- Handle return value of devm_ioremap.
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On Mon, 12 Dec 2016 17:32:58 +0100
Robert Jarzmik <robert.jarzmik@free.fr> wrote:

> arvind Yadav <arvind.yadav.cs@gmail.com> writes:
> 
> > There is problem, if you will use devm_ioremap_resource instead of devm_ioremap,
> > than devm_ioremap_resource will call request_mem_region().
> > request_mem_region() allows to tell the kernel that this driver is going to use
> > this range of I/O addresses, which will prevent other drivers to make an
> > overlapping call to request_mem_region If other driver want to use same address
> > space to access then it will not allow. Means we can not share same address
> > space
> > between two driver.  
> 
> Hi,
> 
> You're right Arvind, and still, it's worth noticing that the docg3 access
> semantics imply a "reserved" resource path (see how doc_register_readb() does a
> write and how this cannot be shared with another driver).
> 
> Therefore I'll be willing to ack a mix of your both patches, the
> devm_ioremap_resource() from Boris and the error message from your patch.

devm_ioremap_resource() already prints different error messages
depending on the error type [1], no need to duplicate it.

[1]http://lxr.free-electrons.com/source/lib/devres.c#L134