From patchwork Thu May 4 07:58:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matti Vaittinen X-Patchwork-Id: 13230853 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CDF65C7EE21 for ; Thu, 4 May 2023 07:59:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229853AbjEDH7I (ORCPT ); Thu, 4 May 2023 03:59:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41698 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229643AbjEDH7H (ORCPT ); Thu, 4 May 2023 03:59:07 -0400 Received: from mail-lf1-x135.google.com (mail-lf1-x135.google.com [IPv6:2a00:1450:4864:20::135]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E124C9D; Thu, 4 May 2023 00:59:04 -0700 (PDT) Received: by mail-lf1-x135.google.com with SMTP id 2adb3069b0e04-4ec8eca56cfso184240e87.0; Thu, 04 May 2023 00:59:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1683187143; x=1685779143; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=BIF36cvrfg5bPNVRii+KXkGpKFjEd7XgQtb3zlxbdA8=; b=hx0RcCUdcJj3keFiQ1VmBrnDvoeRvWwOQYzCEHTk6t/7pQ1PC6VitbsB+dNluLDljq UWKNKhlOYILAvzzAEbs5AHJnKxsDEY5nHgsQ9a8KSpXhwNv+Zwcmp/zxgc9wZZ2Vmcun UpLbjyJltCgInvRAl+OEltTGfasLlL93JugGSFOT3zivvBwjMBps9XzApFAnjQKmfSaB GS+Lj/WdM+Rh1NyJqXCQQLRXlfjukBwxNBFI1GYcsaNvadAr4DbpnfmMGXZcQ7slEvEi 3VnoySHwewC615upD1zc/sCWY11+UwPbOSFeeuGR14my5ZrqeTGV3UM5uPxkb2XHRyfm WIRg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683187143; x=1685779143; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=BIF36cvrfg5bPNVRii+KXkGpKFjEd7XgQtb3zlxbdA8=; b=XDy/vc3XQdXM/ZCPm2p57tSsfLUMA0YKFiiycuVrqW9p5vw75nHMWpKHY3MPMlXeJA G32GOZMnBMQNPdL93i+eqlEtLzdkWccqCFZ4tbqElxBsbNG9OODFJIbJ1tZhnBsgNAbq AnXE73btmXzoq66RrpiiFVrKSflnC9uFoQFO99OZTBCByjSR5NEOnjGDqWuiiPb0LJvm Y9MUYK7tinLKAxWeuE1sEzQCLJmz4g0uLIuWqClD04DR4AOsj6Q5fXXoGwufYwvNX7S5 Pc229zFrmxspsE6FfCRTUlajphxP7auCd2PwQxHdQFkHmUlHSFSEz+JuWLFvcyP9NNSF dITQ== X-Gm-Message-State: AC+VfDwlFtHmbLAKP+gLHfrv8NzVl2LFZjnDRgMGGMIzqQ/S7XUJ2F4n iGwRkr1142v7+/5wl1drH04= X-Google-Smtp-Source: ACHHUZ7vHsckvIiX6G2UgzDWOaS6ak81jjWn6OJakr1hKU4XopSwB5c5fdUnN15BhMsd/9sPj0AQ9A== X-Received: by 2002:ac2:562f:0:b0:4f1:44c0:b08d with SMTP id b15-20020ac2562f000000b004f144c0b08dmr229457lff.29.1683187143097; Thu, 04 May 2023 00:59:03 -0700 (PDT) Received: from fedora (62-78-225-252.bb.dnainternet.fi. [62.78.225.252]) by smtp.gmail.com with ESMTPSA id y24-20020ac24478000000b004f11e965308sm2214506lfl.20.2023.05.04.00.59.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 04 May 2023 00:59:02 -0700 (PDT) Date: Thu, 4 May 2023 10:58:52 +0300 From: Matti Vaittinen To: Matti Vaittinen , Matti Vaittinen Cc: Matti Vaittinen , Jonathan Cameron , Lars-Peter Clausen , linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH 3/3] iio: kx022a: Probe asynchronously Message-ID: <24cea76c282a28b7a4dba297ab627176f8097907.1683185765.git.mazziesaccount@gmail.com> References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org Devices which may take a while to initialize during probe and which have no strong reason to probe synchronously can request asynchronous probing as default probe strategy. This can speed-up start times on some platforms. The KX022A gets probe delayed for at least two reasons. It enables the supply regulator, (which is likely to have ramp-up delay if it was disabled) and additionally it delays while the sensor itself is initializing. Changing to asynchronous probing may cause problems. Some of which are discussed in: https://lore.kernel.org/all/06db017f-e985-4434-8d1d-02ca2100cca0@sirena.org.uk/ Enable asynchronous probing for KX022A. Signed-off-by: Matti Vaittinen --- I am unsure if this change is 100% safe - but I don't immediately see the harm. Please let me know if some of you have more experience on problems when using asynchronous probing with IIO devices. --- drivers/iio/accel/kionix-kx022a-i2c.c | 1 + drivers/iio/accel/kionix-kx022a-spi.c | 1 + 2 files changed, 2 insertions(+) diff --git a/drivers/iio/accel/kionix-kx022a-i2c.c b/drivers/iio/accel/kionix-kx022a-i2c.c index e6fd02d931b6..ee982206e5dd 100644 --- a/drivers/iio/accel/kionix-kx022a-i2c.c +++ b/drivers/iio/accel/kionix-kx022a-i2c.c @@ -40,6 +40,7 @@ static struct i2c_driver kx022a_i2c_driver = { .driver = { .name = "kx022a-i2c", .of_match_table = kx022a_of_match, + .probe_type = PROBE_PREFER_ASYNCHRONOUS, }, .probe_new = kx022a_i2c_probe, }; diff --git a/drivers/iio/accel/kionix-kx022a-spi.c b/drivers/iio/accel/kionix-kx022a-spi.c index 9cd047f7b346..f45a46899a5f 100644 --- a/drivers/iio/accel/kionix-kx022a-spi.c +++ b/drivers/iio/accel/kionix-kx022a-spi.c @@ -46,6 +46,7 @@ static struct spi_driver kx022a_spi_driver = { .driver = { .name = "kx022a-spi", .of_match_table = kx022a_of_match, + .probe_type = PROBE_PREFER_ASYNCHRONOUS, }, .probe = kx022a_spi_probe, .id_table = kx022a_id,