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Date:   Wed, 20 Jan 2021 16:02:05 +0100
From:   Michael Walle <michael@walle.cc>
To:     Tudor.Ambarus@microchip.com
Cc:     vigneshr@ti.com, p.yadav@ti.com, miquel.raynal@bootlin.com,
        richard@nod.at, linux-mtd@lists.infradead.org,
        linux-kernel@vger.kernel.org, Kavyasree.Kotagiri@microchip.com
Subject: Re: [PATCH v2 2/2] mtd: spi-nor: sst: Add support for Global Unlock
 on sst26vf
In-Reply-To: <ad0cc416-73b7-f626-115f-d192fac17957@microchip.com>
References: <20210120131914.277363-1-tudor.ambarus@microchip.com>
 <20210120131914.277363-2-tudor.ambarus@microchip.com>
 <b3a61abec8927c7229c27415d2c769a8@walle.cc>
 <ad0cc416-73b7-f626-115f-d192fac17957@microchip.com>
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Am 2021-01-20 15:52, schrieb Tudor.Ambarus@microchip.com:
> On 1/20/21 4:05 PM, Michael Walle wrote:
>>> diff --git a/drivers/mtd/spi-nor/sst.c b/drivers/mtd/spi-nor/sst.c
>>> index 00e48da0744a..d6e1396abb96 100644
>>> --- a/drivers/mtd/spi-nor/sst.c
>>> +++ b/drivers/mtd/spi-nor/sst.c
>>> @@ -8,6 +8,39 @@
>>> 
>>>  #include "core.h"
>>> 
>>> +static int sst26vf_lock(struct spi_nor *nor, loff_t ofs, uint64_t 
>>> len)
>>> +{
>>> +     return -EOPNOTSUPP;
>>> +}
>>> +
>>> +static int sst26vf_unlock(struct spi_nor *nor, loff_t ofs, uint64_t
>>> len)
>>> +{
>>> +     if (ofs == 0 && len == nor->params->size)
>>> +             return spi_nor_global_block_unlock(nor);
>> 
>> 
>> Some blocks might not be unlocked because they are permanently
>> locked. Does it make sense to read BPNV of the control register
>> and add a debug message here?
> 
> It would, yes. If any block is permanently locked in the unlock_all 
> case,
> I'll just print a dbg message and return -EINVAL. Sounds good?

spi_nor_sr_unlock(), atmel_at25fs_unlock() and atmel_global_unprotect()
will return -EIO in case the SR wasn't writable.

-michael