From nobody Sat Jul 25 04:54:18 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 A439D35AC32; Fri, 17 Jul 2026 20:50:36 +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=1784321437; cv=none; b=AWp8VkEre0/84IFXrT50u+Z0sAWzSThQUZJbAs0vxZYaPMujrpGwjSlkXWwYAQSvZTAs96i8vBSEtdNHbkJ8De7fuAjSGQcUWwmj6zHsefsBEm0sj5n/ir6FJif+gx68ofSNFmJAt/kJrWS44O6faigNr6uNlNd4gtBjK0haWMg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784321437; c=relaxed/simple; bh=RETl3eLQxfArN1LuhdDjN1jvLsKi+ZcQVlq01MjdT1Q=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=d1hMoWk7YfXbFLmTacje8Rz5h01JWf2HsXjNuyvOPbGDCj7S6sOwNwTcqSMHpdgpkRD3fJ7DNPZlJMkeKM7awk8hgW2PmbU5nhOu9l26SOJp0fVLdSi+dGSXmRFYlpliYI+Q2+M4wec9Ya0D4zKW9+nAy1OiDevqVUd9zS1Zg3Q= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=g7u0Y2oK; 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="g7u0Y2oK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2D7001F000E9; Fri, 17 Jul 2026 20:50:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784321436; bh=NgTdbtddBGMa2gMghd5GgSzDtP6TQvkrOxvm5+yLuD8=; h=From:To:Cc:Subject:Date; b=g7u0Y2oKc9YT3bEgJ1/b4iG3FWlgg8d0h38WD9le2dSCIBQDAvzx6AbPsO/uhE5C9 vx7ED6T2HkVd0QHWcyR+iBV2gdSfwoUCPM97zXxNtP8VVCfNP/hAF4U2ShO3dERdlM L64opdmuKT/rLqu7Moz46CRBFPEAbZK4gA6RYxBrDXOzDourzqIqgzS6cFKgUr/d8v SNaiXxvV58F8mzM67T7RMX0Py/CLYUdWbatjDCbzZYLHQtqJiKXVytHK1amZSZSS9e +2GtvSNhVqUlE/Kn9LrQdgxxM8gPBmzBQ6yEBXdcjNQSWdGLawXKdQxkNopjfxkvWp 1Z4sI+umM2Ugw== 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 v1] regmap: Clarify _regmap_update_bits() 'async' kernel-doc Date: Fri, 17 Jul 2026 15:50:31 -0500 Message-ID: <20260717205031.197980-1-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 '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. Assisted-by: Gemini:3.1 Pro Signed-off-by: Bjorn Helgaas --- drivers/base/regmap/regmap.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index e6e022b02637..430dc8233c40 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -3296,11 +3296,11 @@ static int _regmap_update_bits(struct regmap *map, = unsigned 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, most buses + * require synchronous reads, so the read-modify-write cycle will still + * block on the read unless the device uses a register cache. Therefore, + * this flag is most useful for cached devices, where the current value can + * be read from memory without hardware I/O. * * Returns zero for success, a negative number on error. */ --=20 2.53.0