Messages in this thread | | | Date | Sat, 28 Aug 2010 16:18:51 -0700 (PDT) | From | David Brownell <> | Subject | Re: [PATCH] GPIO: add support for NXP 74HC164 GPIO expander |
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--- On Sat, 8/28/10, Florian Fainelli <florian@openwrt.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...
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