From nobody Sat Jul 25 00:47:27 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 A0DC346D543; Tue, 21 Jul 2026 15:49:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784648947; cv=none; b=VazFeYqetE0jKvCPklumCYTGJMi1crrKtnDAM156Y+HSxQJxNYxLshVkWPVMRcmeBsbhKIPYXPWXKVW22ufpFYIm7BPt3uOW3U8SWz3eOfAzAHtHrasBN1j6j/w+eGHBZrZ+C5QTlWtFmRXVtuYYN9N1bohwqexfdUi6ovcDkzg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784648947; c=relaxed/simple; bh=tWLKvSwHd/12fPv1tFRPpB6yvf1qvD8/kriGpC/rAbs=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=neE7zDUVWb9lx8NLw8OW/1SA3Nq4zPzJEI5Ju5ryH7ToXzVzD+Ttd40M3wOLR/7BzV1HqwyDR5OQA1IQeqMftQv7y5qqn/Hl7H3OcbWvUwZj69MJfaRIzcZAL76gQCHSZHqDQwQHzhUO5XunUilQOaU7ziZ7K0j78niBVRL7njo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IwJBrFNB; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="IwJBrFNB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 48E131F00A3A; Tue, 21 Jul 2026 15:49:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784648946; bh=X1i7lG2IapMmAixltdm5Db6EAqu8CMqr4RwEK0vzIAU=; h=From:To:Cc:Subject:Date; b=IwJBrFNBeQLntLQcDytTgo2g6ecxisdBUXp02VX7w3MTX2ud7Q2hLJnCZfc1+FuVu r/9faUrwEcHTZtVqdhnl1g9lIEWCrBHIwZYa0iC8JquSc8wRJU0a1y0DQbftYM5ngA CVuWezLHJ3n8AbgnFNQ1nIs3MyoOF13jHBcrgRaFsocG7pjcABMt0hIfeA1ipgQ9sx Uby+VlhqrO4/Ci4Xx+WpkRcLQXHMatU2XMKA8a4GugVf+g5exf8mcxkD1b4rSOn+pp 5UskKU2XxPXmmbK20bsclkQ8c+Wb7yH8jkcf5hWfoHQHm3zeSBVpd+7+LvucmKyNbR 1T/nnzFKTnRWg== From: Bjorn Helgaas To: Mark Brown Cc: Kuninori Morimoto , Greg Kroah-Hartman , "Rafael J . Wysocki" , Danilo Krummrich , driver-core@lists.linux.dev, linux-kernel@vger.kernel.org, Bjorn Helgaas Subject: [PATCH v2] regmap: Clarify regmap_update_bits_base() 'async' kernel-doc Date: Tue, 21 Jul 2026 10:49:02 -0500 Message-ID: <20260721154902.566531-1-bhelgaas@google.com> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The kernel-doc for the regmap_update_bits_base() 'async' parameter didn't actually say what it does. Reword it to clarify the read-modify-write mechanics: when 'async' is true, the write is queued asynchronously, but the read will still be synchronous unless the device uses a register cache. Signed-off-by: Bjorn Helgaas --- Changes since v1: - Shorten doc, mention the correct function in subject v1: https://lore.kernel.org/all/20260717205031.197980-1-bhelgaas@google.com drivers/base/regmap/regmap.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index e6e022b02637..d0deddec516f 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -3296,11 +3296,9 @@ static int _regmap_update_bits(struct regmap *map, u= nsigned int reg, * Perform a read/modify/write cycle on a register map with change, async,= force * options. * - * If async is true: - * - * With most buses the read must be done synchronously so this is most use= ful - * for devices with a cache which do not need to interact with the hardwar= e to - * determine the current register value. + * If async is true, queue an asynchronous write. However, reads are + * synchronous on most buses, so they will still block unless the device + * uses a register cache. * * Returns zero for success, a negative number on error. */ --=20 2.53.0