linux-kernel - Re: [PATCH] GPIO: add support for NXP 74HC164 GPIO expander

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-next>] [day] [month] [year] [list]

Message-ID: <461057.78283.qm@web180310.mail.gq1.yahoo.com>
Date:	Sat, 28 Aug 2010 16:18:51 -0700 (PDT)
From:	David Brownell <david-b@...bell.net>
To:	linux-kernel@...r.kernel.org, akpm@...ux-foundation.org,
	Samuel Ortiz <sameo@...ux.intel.com>,
	Miguel Gaio <miguel.gaio@...xo.com>,
	Juhos Gabor <juhosg@...nwrt.org>,
	David Brownell <dbrownell@...rs.sourceforge.net>,
	Florian Fainelli <florian@...nwrt.org>
Subject: Re: [PATCH] GPIO: add support for NXP 74HC164 GPIO expander

--- On Sat, 8/28/10, Florian Fainelli <florian@...nwrt.org> wrote:

> This patch adds support for
> NXP's 74HC164 GPIO expander.

The 74164 parts are standard 74xxx series
discrete logic parts sold by many vendors
as 8 bit shift registers ... and in many
logic series (HC, HCT, more).

At least describe this as generic to all
those 8-bit shift registers, not just NXP.
And not as "GPIO expanders"; data sheets
describe them as shift registers.  Kconfig
can say that the shift registers are being
used for GPIO (output) expansion.

I suppose it's reasonable not to support the
way these chips can be daisy-chained, but it'd
be worth a comment, IMO; that strikes me as a
think someone will add at some point, via some
platform data (e.g.32 GPIO outputs from 4 chips).

- Dave

p.s. I'd have to pull out my data sheet collection
to verify, but it might be the 74163 which can
be used as an 8 bit parallel to serial (input)
 shift register...

--
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/