RE: [PATCH] NFC: Driver for Inside Secure MicroRead NFC chip

From: Waldemar.Rymarkiewicz
Date: Thu Mar 17 2011 - 08:58:58 EST

Hi Arnd,

>> >Note that the microread_is_busy() logic does not protect you from
>> >having multiple concurrent readers, because multiple threads may
>> >share a single file descriptor.
>> It's just used to ensure that only one reader can open the device.
>> It's called only in open callback.
>> The mutex actually secures concurrent read operations.
>So if having multiple readers is safe (though possibly not
>meaningful), I guess you don't really need the
>microread_is_busy() logic.
>I suppose it doesn't hurt either, it just seems a bit
>pointless when it does the right thing most of the time, but
>not always.

Could you give me an example when the microread_is_busy() logic does not do what it's intended to do.
I don't really get your point here.

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