Re: [PATCH 3/4] dt-bindings: gpio: max3191x: Document new driver
From: Lukas Wunner <lukas@wunner.de>
Date: 2017-09-05 08:16:24
Also in:
linux-gpio
From: Lukas Wunner <lukas@wunner.de>
Date: 2017-09-05 08:16:24
Also in:
linux-gpio
Hi Rob, sorry to bother you again, one more question popped up regarding the MAX3191x DT bindings: On Tue, Aug 22, 2017 at 07:48:47PM -0500, Rob Herring wrote:
On Mon, Aug 21, 2017 at 03:12:00PM +0200, Lukas Wunner wrote:quoted
Add device tree bindings for Maxim MAX3191x industrial serializer.
[snip]
quoted
+Optional properties: + - maxim,nchips: Number of chips in the daisy-chain (default is 1).
Many I/O chips are daisy-chainable, so I've been wondering if a common property should be introduced? The existing gpio-74x164.c uses "registers-number" to convey the number of chips in the daisy chain. (Sans vendor prefix, multiple vendors sell compatible versions of this chip.) gpio-pisosr.c takes a different approach and calculates the number of chips in the daisy-chain by taking the common "ngpios" property (Documentation/devicetree/bindings/gpio/gpio.txt) and dividing it by 8 (which assumes that each chip has 8 inputs). Thanks, Lukas