From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 99CFD306B12; Wed, 7 Jan 2026 11:20:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767784833; cv=none; b=thSniVpTCpJ3Nd0KyTaeAb5I25nGbkUDCqlsPiG57xsIwrNt+/Ji5e39RuPg+LAKSYgMsPyD6AuRoT2MUw4Eb6j7efpJqoTl8r5PBZJaynpWyaHHyPPSE35Sa4eHzz0TFruXqUOXUzNDpMhOUEr8jaJchPnZd1ItyQPFmh4hKc4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767784833; c=relaxed/simple; bh=6k8C8yI5WkA7y91OjqXKV/JNd5xATCrdAT88kc+n41o=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ihwNMfBgAPy56q4mb9FNxRyCBl7IwLKxF/noy6qIYpOhOQkmBIT/V40CXN3XyvS2CXWPwjRh383qG/MXAdjby+HIcmHCGq6qBkm6VCFD7m2jECf+PWQc0DfDt79L9rYNxJAWGTwZgFRcdVqV6o8VsfTE3lNFZQnYw0WHfb9mar4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=m57v/CzX; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="m57v/CzX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 999E2C4CEF7; Wed, 7 Jan 2026 11:20:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1767784832; bh=6k8C8yI5WkA7y91OjqXKV/JNd5xATCrdAT88kc+n41o=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=m57v/CzXudJeWWfRk4SJ+wY+IBxkvzJW79HM/DuE1qHQ1DzZwLhCovQ14H3wRPyh2 /mj72vWezqkYVvp61lHUYSWrcBwWtw237sgh2x1Bi/zhwKkEbdfwNikX9G3PQvAVih t7v3eawfS2iaJw/cfTDiIB5jP4f3XrAVeoOc6GfM21wmLC//0nOSEcTfkD5k4AH+BK DiBFwmo94aoj/8Bb+8iHi6Ku7cTk8HlH5Ovh2Z1I/Sf4Mud0kOz59SQahPmDLaHyE6 4pXhDMdeSqRnLW43dvXE9BDXARWy+AyvxFFdD8rcnbBRne3zOlA4cNtH+7toVP000U znytBGJb9KGVg== Date: Wed, 7 Jan 2026 11:20:26 +0000 From: Mark Brown To: "Sheetal ." Cc: Sander Vanheule , Greg Kroah-Hartman , "Rafael J . Wysocki" , Danilo Krummrich , Liam Girdwood , Jaroslav Kysela , Takashi Iwai , Thierry Reding , Jonathan Hunter , linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org, linux-tegra@vger.kernel.org Subject: Re: [RFC PATCH 1/2] regmap: Add cache_default_is_zero flag for flat cache Message-ID: <0ece3e08-3ffc-418c-9e7b-eaf098fb49bc@sirena.org.uk> References: <20260106140827.3771375-1-sheetal@nvidia.com> <20260106140827.3771375-2-sheetal@nvidia.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="uvdXBJvVo8ErMtAg" Content-Disposition: inline In-Reply-To: X-Cookie: Is there life before breakfast? --uvdXBJvVo8ErMtAg Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Jan 07, 2026 at 12:25:01PM +0530, Sheetal . wrote: > On 06-01-2026 20:42, Mark Brown wrote: > > Why do this on first read rather than than just fill the valid flags > > during initialisation? > Setting valid bits on first read rather than bitmap_fill() at init ensures: > - Only accessed registers are marked valid > - regcache_sync() only syncs registers that were actually used > - Avoids writes to holes or unused registers during sync > - Safer for drivers without writeable_reg callback Seems reasonable, put that in the changelog please. BTW I forgot in my initial review but please add KUnit coverage for this, we've got good coverage of the cache code. --uvdXBJvVo8ErMtAg Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmleQXkACgkQJNaLcl1U h9CHkwf8CNTTkQeUt6Sxa8SmwHkh5gaWf+7tcTQug4yQQw7v190U/ecqE89p582g uE+8lSTLJHfE27lTN5JCNd80yPs2bW23rJOoM9pehhszV2+m13qLRcuZSOudonrO PX+cMdt5S1A+imKbD+OsvVIT1XxBPUCu6FjKPLLRrPA4SwWC8g/QneIR689nj8ou seVy9Hpvv7CA2990yFtXf28XC0TZ4X6KJwi480mT5hGAGFhebu9L56xsueiLEPHG 5RBHaWb61HQmpcvesAq9Mldk80bN4/ReOcrKfTUduMNhzshk+GvZpxANkQA25SZu Op8umCgR4+W5zSvRD6nqg3ORga1BPg== =uFXo -----END PGP SIGNATURE----- --uvdXBJvVo8ErMtAg--