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From:   Chris Packham <Chris.Packham@alliedtelesis.co.nz>
To:     Richard Weinberger <richard.weinberger@gmail.com>
CC:     David Woodhouse <dwmw2@infradead.org>,
        Brian Norris <computersforpeace@gmail.com>,
        Marek Vasut <marek.vasut@gmail.com>,
        "Miquel Raynal" <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        "linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 2/2] mtd: concat: implement _is_locked mtd operation
Thread-Topic: [PATCH 2/2] mtd: concat: implement _is_locked mtd operation
Thread-Index: AQHVEDJo0iBq93PH/EeJquPgUtfeew==
Date:   Wed, 22 May 2019 21:06:48 +0000
Message-ID: <0c59bcd6c866429cb9727f787b7f61ce@svr-chch-ex1.atlnz.lc>
References: <20190522000753.13300-1-chris.packham@alliedtelesis.co.nz>
 <20190522000753.13300-2-chris.packham@alliedtelesis.co.nz>
 <CAFLxGvy2c9KV1CyoFaD76jvThfPiotqfoeNchqjGcDp+uHie7Q@mail.gmail.com>
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On 23/05/19 8:44 AM, Richard Weinberger wrote:=0A=
> On Wed, May 22, 2019 at 2:08 AM Chris Packham=0A=
> <chris.packham@alliedtelesis.co.nz> wrote:=0A=
>>=0A=
>> Add an implementation of the _is_locked operation for concatenated mtd=
=0A=
>> devices. As with concat_lock/concat_unlock this can simply use the=0A=
>> common helper and pass mtd_is_locked as the operation.=0A=
>>=0A=
>> Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>=0A=
>> ---=0A=
>>   drivers/mtd/mtdconcat.c | 6 ++++++=0A=
>>   1 file changed, 6 insertions(+)=0A=
>>=0A=
>> diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c=0A=
>> index 9514cd2db63c..0e919f3423af 100644=0A=
>> --- a/drivers/mtd/mtdconcat.c=0A=
>> +++ b/drivers/mtd/mtdconcat.c=0A=
>> @@ -496,6 +496,11 @@ static int concat_unlock(struct mtd_info *mtd, loff=
_t ofs, uint64_t len)=0A=
>>          return __concat_xxlock(mtd, ofs, len, mtd_unlock);=0A=
>>   }=0A=
>>=0A=
>> +static int concat_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t =
len)=0A=
>> +{=0A=
>> +       return __concat_xxlock(mtd, ofs, len, mtd_is_locked);=0A=
>> +}=0A=
> =0A=
> Hmm, here you start abusing your own new API. :(=0A=
=0A=
Abusing because xxlock is a poor choice of name? I initially had a third =
=0A=
copy of the logic from lock/unlock which is what lead me to do the =0A=
cleanup first. mtd_lock(), mtd_unlock() and mtd_is_locked() all work the =
=0A=
same way namely given an offset and a length either lock, unlock or =0A=
return the status of the len/erasesz blocks at ofs.=0A=
=0A=
> =0A=
> Did you verify that the unlock/lock-functions deal correctly with all=0A=
> semantics from mtd_is_locked?=0A=
> i.e. mtd_is_locked() with len =3D 0 returns 1 for spi-nor.=0A=
> =0A=
=0A=
I believe so. I've only got access to a parallel NOR flash system that =0A=
uses concatenation and that seems sane  (is mtdconcat able to work with =0A=
spi memories?). The concat_is_locked() should just reflect what the =0A=
underlying mtd device driver returns.=0A=