From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0B620606B99C for ; Tue, 10 Nov 2026 10:24:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=scUUkhAH; dkim=pass (2048-bit key, unprotected) header.d=sang-engineering.com header.i=@sang-engineering.com header.a=rsa-sha256 header.s=k1 header.b=CixjJzFD DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Unsubscribe-Post:List-Owner; bh=0k92K8b49X9cIdh2GF82mc+d2Q8OVuyS6TzYE36ZPtE=; b=scUUkhAHFgR2nAei6JZd0IU4oR +KUoysOhWp+MIJwCto7B4o7BiPKFU0I2oQPbrYh96Tx3lXwXZ6ogYYAsvCEo/ZlnWQFNMsq/le28f xddxRpri/ef8Lk/RUmIijB9+57gTAjrLQDdAJ4WB5dYh6pJUbKzB4OK89iUgZ32kH88RCi2BD0W+9 NyOr5HEIdTOuhTrFu6huH6G/E7ulDXVlk+jAjDFJH9LZnM8bTc25ZLvkRzet7cYAJrhsdN2K/VhQF 9knXXV/dm/cDCBo1RLQ23GYhqabKTfeHDAw2NYrNfhlGQ9QFUW8Tr99G3RH0bjF/neRJGpT9ubqBe P62triFg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xQj1n-00000003RxQ-3LBb; Tue, 10 Nov 2026 10:24:35 +0000 Received: from zeus03.de ([194.117.254.33] helo=mail.zeus03.de) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xQj1j-00000003Rv7-0Wg0 for linux-mediatek@lists.infradead.org; Tue, 10 Nov 2026 10:24:34 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= sang-engineering.com; h=date:from:to:cc:subject:message-id :references:mime-version:content-type:in-reply-to; s=k1; bh=0k92 K8b49X9cIdh2GF82mc+d2Q8OVuyS6TzYE36ZPtE=; b=CixjJzFDIKVpJGj+e0HN K1hHUYCLcVXcQKua5AIHTqIEXd5XLR2K1xiTJiW2GZNBtgbADz+FWMM9nZCm5O2A ZuOK98Piur0oC5bOuegmdwsw69YpeqRvB7bwO92tbfcETkfdXVUD92zjWf6oteO6 XKkCKkyuLtfqXlmZriJXEm7hdU9Iyuw3nI7V9OP/3t/+WHRZG95vERR+3slbMEg+ a0OOYfzzjZax/bZsoodgw4a8unf3OW/TkvCAUmHGjZKm8h5uvQ1C9b2Qe8gikhna 7D9iw2niRkO5MQh3Xk8tUGLp562kgtB84GdmAOkIZkeIxxtr+6Gaj4Gt84AXxuPH gg== Received: (qmail 187841 invoked from network); 10 Nov 2026 11:24:25 +0100 Received: by mail.zeus03.de with ESMTPSA (TLS_AES_256_GCM_SHA384 encrypted, authenticated); 10 Nov 2026 11:24:25 +0100 X-UD-Smtp-Session: l3s3148p1@rcKKe+lfZuoujnsO Date: Tue, 10 Nov 2026 11:24:24 +0100 From: Wolfram Sang To: Chen-Yu Tsai Cc: Mark Brown , Matthias Brugger , AngeloGioacchino Del Regno , Dmitry Torokhov , Jiri Kosina , Andi Shyti , Benson Leung , Tzung-Bi Shih , linux-mediatek@lists.infradead.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, chrome-platform@lists.linux.dev, linux-input@vger.kernel.org, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v7 4/8] i2c: of-prober: skip post-power-on delay if powered on sufficiently long Message-ID: References: <20261103043734.2179858-1-wenst@chromium.org> <20261103043734.2179858-5-wenst@chromium.org> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261103043734.2179858-5-wenst@chromium.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261110_022432_027937_864D007A X-CRM114-Status: GOOD ( 16.12 ) X-Spam-Score: -2.1 (--) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" X-Spam-Status: No, score=-10.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Tue, Nov 03, 2026 at 12:37:28PM +0800, Chen-Yu Tsai wrote: > On some devices the I2C component is powered from an always-on power > rail, or the power rail has been left on by either POR defaults or > the bootloader. By the time the prober probes the device, the device > most certainly has finished initializing and can respond. There is no > need for the delay. > > In such designs, the system integrators tend to work around the delay > to avoid the boot time penalty by simply omitting it from the device > tree and the component prober. This is undesired, as the device tree > is not fully describing the hardware. > > Switch to the new regulator_enable_and_wait() function that makes sure > a certain amount of time has passed since the regulator supply was > actually enabled. > > Signed-off-by: Chen-Yu Tsai Acked-by: Wolfram Sang @Andi: Chen-Yu is the maintainer of the of-prober, so I suggest these changes just go in together with this series.