From nobody Mon Sep 28 10:00:08 2026 Received: from mta-64-228.siemens.flowmailer.net (mta-64-228.siemens.flowmailer.net [185.136.64.228]) (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 02A10374E7A for ; Mon, 24 Aug 2026 08:08:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.136.64.228 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787558899; cv=none; b=Au2Cv/+mOxnf+AEdApIMfy6o0yVjbh2NCr0+1i6xXM4WW65O2T7jl2wjk4joPKL0iO3+NSicFJ+ZXapo3qUxDppgbzbK91AlxMmqAixaVfPX8LaBgH0+E5YNqIqLc3JOskdkfhmbhy/cloTDJ5McoePtzgHBpRB6ZL32X2EGUkk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787558899; c=relaxed/simple; bh=3G3ulFFSHUc92tcBjHrT3b0QYJS6jk2XY7uHx8whOEw=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=iRiHt3OWcZA04h+AxsSWjoOQVPY6XM2n+tup+/vJi/jEYyPsmME8tY///QMdaQWF3j0TzXFueJTfkE+bYOoRnH7Y7AHhygzNxQh2pFJpJ4BGzg68nCUsx/tQMO60j1Ie2emrVa4+9zMAT8nD3RZRqFg6Lg6xyl3xAXE9s0M2n3k= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=siemens.com; spf=pass smtp.mailfrom=rts-flowmailer.siemens.com; dkim=pass (2048-bit key) header.d=siemens.com header.i=alexander.sverdlin@siemens.com header.b=M4mClQCs; arc=none smtp.client-ip=185.136.64.228 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=siemens.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rts-flowmailer.siemens.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=siemens.com header.i=alexander.sverdlin@siemens.com header.b="M4mClQCs" Received: by mta-64-228.siemens.flowmailer.net with ESMTPSA id 20260824080806f8c8b671be00020780 for ; Mon, 24 Aug 2026 10:08:06 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; s=fm2; d=siemens.com; i=alexander.sverdlin@siemens.com; h=Date:From:Subject:To:Message-ID:MIME-Version:Content-Type:Content-Transfer-Encoding:Cc; bh=BdgGWbXQkpW4OTCJgHhpsVIoB/AjFsBplkgEDxA6l/s=; b=M4mClQCsUKYK0m4i1G9B/xQ11nTpPaKS31dNqPap+EdAYkEVlnbt+PNbh2XtnN3ked9e4c mlJiXDEizv8S7l48vlZszLvLUeU6uwAM6E7JX7zT6+0X7g408wt+hFmA4T61oqTIYTzLk94G qET8pgSQlc+HxIMdVfcN5G0B7a2Rrs+dUPByyNLh9t+s0JvnwwcjM4jflYLE/rTHlfh9ZQpZ ck/e+LsBU5dMPYkVUdajikxzR77gdJvG5ohRILZjNAGJHGV/pbzKQBv/h47jmmW02GVxQJvz NCNZv/QGnTqIBV7J5FSBXYgPtPjtKJsGN8AVI6N6g+cCVUN+5493N78Q==; From: "A. Sverdlin" To: linux-rtc@vger.kernel.org Cc: Alexander Sverdlin , Alexandre Belloni , linux-kernel@vger.kernel.org Subject: [PATCH] rtc: pcf85063: disable the clkout output by default Date: Mon, 24 Aug 2026 10:07:59 +0200 Message-ID: <20260824080801.709764-1-alexander.sverdlin@siemens.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Flowmailer-Platform: Siemens Feedback-ID: 519:519-456497:519-21489:flowmailer From: Alexander Sverdlin The PCF85063 powers up with its CLKOUT pin driving the 32.768 kHz. While it's possible to request a specific default frequency in the DT via assigned-clocks/assigned-clock-rates on the RTC node itself, even without a real consumer referencing the clock, there is no such possibility to disable the clock output by default. Therefore gate CLKOUT in the driver before registering the OF provider, mirroring the pcf8563 and hym8563 siblings which already force an off state at registration. Doing it before devm_of_clk_add_hw_provider() leaves the real consumers in the device tree free to re-enable the output afterwards, while an otherwise unused CLKOUT now stays off. In practice it means that with CLKOUT disabled the RTC consumes around 250nA at 25=C2=B0C and 6-10uA with CLKOUT enabled (5v Vdd). Which means day= s vs hours on a supercapacitor. Signed-off-by: Alexander Sverdlin --- drivers/rtc/rtc-pcf85063.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/rtc/rtc-pcf85063.c b/drivers/rtc/rtc-pcf85063.c index 01e209d88f5f3..0b6d8083b6456 100644 --- a/drivers/rtc/rtc-pcf85063.c +++ b/drivers/rtc/rtc-pcf85063.c @@ -523,6 +523,12 @@ static struct clk *pcf85063_clkout_register_clk(struct= pcf85063 *pcf85063) /* optional override of the clockname */ of_property_read_string(node, "clock-output-names", &init.name); =20 + /* power-on default is the 32768 Hz output on; gate it until claimed */ + ret =3D regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL2, + PCF85063_REG_CLKO_F_MASK, PCF85063_REG_CLKO_F_OFF); + if (ret) + return ret; + /* register the clock */ clk =3D devm_clk_register(&pcf85063->rtc->dev, &pcf85063->clkout_hw); =20 --=20 2.55.0