From patchwork Tue May 7 14:48:17 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 13657275 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 98189160781; Tue, 7 May 2024 14:48:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715093330; cv=none; b=q6b7Xu4VZMupgDhj15HT42hqTpSMrltyXkdgkI4PbKKZjrPasVY3dOSXdvDVffx6YUgwzqS0Ht7EADPpl2+k/XRrcj8Fs7wWDENjbyGq8LOeo+noff6Yz3ur9zqaNYwS4GCLQEN2iguCop7fOzyDIyUyPetky3YLJSNjbFZ4X1U= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715093330; c=relaxed/simple; bh=GIO4K7Jzi7e58ru4SZwn+yKyWIyZbt9nbponGMhXWbs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JF4f9LURaIip+3wH3kEU4jU1SibhHFCNOxcjshRbH30jL8l8lEh/LxWeYJq++odgj5mzCb8ZQa2Tiis8Bg7FU64730zff7tnSwL8UgMxPba6zzVlOBnx9wGsLKD/z3xRUuNGfL96F0XCtet44/TDKuZrGvsyLBwis8OfqH6jJN4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=huv6oeXF; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="huv6oeXF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4017FC4AF68; Tue, 7 May 2024 14:48:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1715093330; bh=GIO4K7Jzi7e58ru4SZwn+yKyWIyZbt9nbponGMhXWbs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=huv6oeXFI2fbbRUp2ra+wqxFNEvKmHMWZFyGScm4lKhBIHOCLWf2cy0VjMX39V0/R CEDdludXc1Uh3+jjTRKWPmkpvYr92jy273U19grzAA8J2akyOBYY2SXzC7h3+8oSrq uNUg1gl+XESUcCzpfgYXcihcL5OeNNZTqHzxAEgfD4m3JiswHtmNBG0ApSodshmXt4 YTTa2o+Pkz6eygeTXNqdimvwCTwxMz7orh9Rk087rEeS8HeYh0RTxwIGe89O5/IXK1 bHrxf/n4tSsbwxTT+2TVfSk/UEWj12+AOzwOhbDUnLoMKuBnQKjz6Kui7m4anB8qWO nk2oLFxArl7Aw== Received: from johan by xi.lan with local (Exim 4.97.1) (envelope-from ) id 1s4M7g-000000003Cs-22KF; Tue, 07 May 2024 16:48:52 +0200 From: Johan Hovold To: Jiri Kosina , Benjamin Tissoires , Bjorn Andersson Cc: Dmitry Torokhov , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Konrad Dybcio , Linus Walleij , Douglas Anderson , linux-input@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, Johan Hovold Subject: [PATCH v2 3/7] dt-bindings: HID: i2c-hid: elan: add 'no-reset-on-power-off' property Date: Tue, 7 May 2024 16:48:17 +0200 Message-ID: <20240507144821.12275-4-johan+linaro@kernel.org> X-Mailer: git-send-email 2.43.2 In-Reply-To: <20240507144821.12275-1-johan+linaro@kernel.org> References: <20240507144821.12275-1-johan+linaro@kernel.org> Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 When the power supply is shared with other peripherals the reset line can be wired in such a way that it can remain deasserted regardless of whether the supply is on or not. This is important as it can be used to avoid holding the controller in reset for extended periods of time when it remains powered, something which can lead to increased power consumption. Leaving reset deasserted also avoids leaking current through the reset circuitry pull-up resistors. Add a new 'no-reset-on-power-off' devicetree property which can be used by the OS to determine when reset needs to be asserted on power down. Note that this property can also be used when the supply cannot be turned off by the OS at all. Signed-off-by: Johan Hovold Reviewed-by: Krzysztof Kozlowski Reviewed-by: Linus Walleij --- Documentation/devicetree/bindings/input/elan,ekth6915.yaml | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml index be84f7ed0abc..a62916d07a08 100644 --- a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml +++ b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml @@ -36,6 +36,12 @@ properties: reset-gpios: description: Reset GPIO; not all touchscreens using eKTH6915 hook this up. + no-reset-on-power-off: + type: boolean + description: + Reset line is wired so that it can (and should) be left deasserted when + the power supply is off. + vcc33-supply: description: The 3.3V supply to the touchscreen.