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From: swarren@wwwdotorg•org (Stephen Warren)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH v1 04/12] input: matrix-keypad: push/pull, separate polarity
Date: Fri, 21 Jun 2013 15:34:01 -0600	[thread overview]
Message-ID: <51C4C6C9.6030000@wwwdotorg.org> (raw)
In-Reply-To: <1371838198-7327-5-git-send-email-gsi@denx.de>

On 06/21/2013 12:09 PM, Gerhard Sittig wrote:
> extend the device tree adjustable hardware configuration:
> - allow for differing polarity of the row and column GPIO pins
> - optionally fully drive column output pins instead of the former
>   unconditional open collector emulation approach

> diff --git a/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt b/Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt

> +- row-gpios-activelow:	row GPIO pins are active low
> +- col-gpios-activelow:	column GPIO pins are active low
>  - gpio-activelow:	row pins as well as column pins are active low
> +			(provided for backward compatibility, and useful
> +			for matrix layouts of identical polarity for
> +			rows and columns)

Those should all come from the existing GPIO flags, and may even differ
for each GPIO.

> +- col-gpios-pushpull:	fully drive the column selection pins in either
> +			direction (high and low signals), the default
> +			behaviour is to actively drive low signals and
> +			be passive otherwise (emulates an open collector
> +			output driver)

We don't actually have GPIO flags defined for pushpull-vs-open-collector
etc. Perhaps we should do so. Then, we wouldn't need to invent custom
properties to represent that in this binding.

  reply	other threads:[~2013-06-21 21:34 UTC|newest]

Thread overview: 45+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-06-21 18:09 [PATCH v1 00/12] input: keypad-matrix: doc update, hw separation, polling, binary columns Gerhard Sittig
2013-06-21 18:09 ` [PATCH v1 01/12] input: matrix-keypad: update devicetree binding doc Gerhard Sittig
2013-06-21 21:31   ` Stephen Warren
2013-06-22  9:23     ` Gerhard Sittig
2013-06-24 22:00       ` Stephen Warren
2013-06-28  8:24         ` Gerhard Sittig
2013-06-28 14:50           ` Stephen Warren
2013-06-30 11:04             ` Gerhard Sittig
2013-06-21 18:09 ` [PATCH v1 02/12] input: matrix-keymap: func call coding style nit Gerhard Sittig
2013-06-22  2:18   ` Marek Vasut
2013-06-22  8:22     ` Gerhard Sittig
2013-06-22 13:23       ` Marek Vasut
2013-06-21 18:09 ` [PATCH v1 03/12] input: matrix-keypad: rename variables and funcs Gerhard Sittig
2013-06-21 18:09 ` [PATCH v1 04/12] input: matrix-keypad: push/pull, separate polarity Gerhard Sittig
2013-06-21 21:34   ` Stephen Warren [this message]
2013-06-22  9:36     ` Gerhard Sittig
2013-06-24 23:14       ` Stephen Warren
2013-06-28  8:33         ` Gerhard Sittig
2013-06-28 15:01           ` Stephen Warren
2013-06-30 11:43             ` Gerhard Sittig
2013-06-21 18:09 ` [PATCH v1 05/12] input: matrix-keypad: update comments, diagnostics Gerhard Sittig
2013-06-22  2:23   ` Marek Vasut
2013-06-21 18:09 ` [PATCH v1 06/12] input: keypad-matrix: refactor matrix scan logic Gerhard Sittig
2013-06-21 18:09 ` [PATCH v1 07/12] input: keypad-matrix: introduce polling support Gerhard Sittig
2013-06-21 21:38   ` Stephen Warren
2013-06-22  9:50     ` Gerhard Sittig
2013-06-24 23:18       ` Stephen Warren
2013-06-21 18:09 ` [PATCH v1 08/12] input: keypad-matrix: tell GPIO pins from matrix lines Gerhard Sittig
2013-06-21 21:41   ` Stephen Warren
2013-06-22 10:00     ` Gerhard Sittig
2013-06-24 23:26       ` Stephen Warren
2013-06-28  7:52         ` Gerhard Sittig
2013-06-28 14:35           ` Stephen Warren
2013-06-28 18:25             ` Dmitry Torokhov
2013-06-30 12:03               ` Gerhard Sittig
2013-06-21 18:09 ` [PATCH v1 09/12] input: matrix-keypad: add binary column encoding Gerhard Sittig
2013-06-21 21:58   ` Stephen Warren
2013-06-21 18:09 ` [PATCH v1 10/12] input: keypad_matrix: use usleep_range() for scan delay Gerhard Sittig
2013-06-21 22:00   ` Stephen Warren
2013-06-22 10:17     ` Gerhard Sittig
2013-06-24 23:27       ` Stephen Warren
2013-06-21 18:09 ` [PATCH v1 11/12] input: keypad-matrix: AC14xx device tree update Gerhard Sittig
2013-06-21 18:09 ` [PATCH v1 12/12] input: matrix-keypad: add diagnostics in probe() Gerhard Sittig
2013-06-22  2:28   ` Marek Vasut
2013-06-22  8:30     ` Gerhard Sittig

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