lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Date:	Fri, 23 Aug 2013 09:47:57 +0000
From:	"Rymarkiewicz, WaldemarX" <waldemarx.rymarkiewicz@...el.com>
To:	Lars Poeschel <poeschel@...onage.de>
CC:	Lars Poeschel <larsi@....tu-dresden.de>,
	"sameo@...ux.intel.com" <sameo@...ux.intel.com>,
	"jslaby@...e.cz" <jslaby@...e.cz>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-wireless@...r.kernel.org" <linux-wireless@...r.kernel.org>,
	"linux-nfc@...ts.01.org" <linux-nfc@...ts.01.org>
Subject: RE: [linux-nfc] [PATCH RFC] nfc: add a driver for pn532 connected
 on uart

Hi,

>Yes, I know that and I explicitly mentioned that. I had to get this chip working
>somehow and I had to begin somewhere. The pn533 driver is really very hard 
>to understand with it's massive use of nested callbacks, workqueues and
>usb urbs. So I took the approach to try to understand what happens while modifying
>and would then later factor out what both drivers have in common.
>The other way is understanding the code first and then decide what would be needed for
> both chips, factor that out and then write the pn532 uart specific stuff. And this uart stuff
>is a pain itself in linux. This way seemed much harder to me,
> especially as I have no pn533 device to test which things will break.

I understand. It took me some time to understand this too. Now, it's even harder after adding  protocol ops, but still is pretty well layered. 

> I suggest to separate transport layer from the core in pn533 and add 
> support for uart and usb separately. This is exactly what I've planned 
> while changing pn533 to support acr122 device.
>> Yes, I agree with you this should be done. I'll expect it to be challenging
>> but based on my previous work this could be doable. 

Be sure there will be pitfalls separating transport.  I've already experienced some of them adding support for acr122. 

>> I'll look into that in my next free timeslot. I'll not be able to do that in the next two months. 
>>Sorry.

No worries. I know this pain :) 

Thanks,
/Waldek
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists