From mboxrd@z Thu Jan 1 00:00:00 1970 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 A67DFC54EBD for ; Fri, 6 Jan 2023 22:01:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236701AbjAFWB4 (ORCPT ); Fri, 6 Jan 2023 17:01:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43634 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236693AbjAFWBL (ORCPT ); Fri, 6 Jan 2023 17:01:11 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 351DF848E2; Fri, 6 Jan 2023 14:00:57 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 80B90CE1E6D; Fri, 6 Jan 2023 22:00:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 50C46C433EF; Fri, 6 Jan 2023 22:00:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1673042453; bh=nY98X/gx6KdA7uOLij50iqYabHvIksPSbU47iL15GCk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LVSEz8npgVEzW/6ZhgEBmyJlBraMWVJelVMT/C0CrxIOdzmNJl8lvGKUXuRc1DmXc 6uB038RuiDYugVZeiT/I6vmzWknWXmJqvMdk3JJaq37AD0WbfvRjSa6SYd1VkICZvA coRBF/pWNUx9OR10Y67++CUXZIVhgqhXBkden9lzD+YYXNrcjtiXjXZYgUYMNA8h1X F6sgeTVfp7XhhyneKZp4D0o3aioc0JiwvMBgiqNHl0NgJoH4phSD0wUYLMto73AL50 U2J23VEgFqgPrxhCSA3nPfqqAykGPoYjdJzLq5VPWzvZCDmiGscvv+DHdIXIMDjDXL XcI99nmPUu1zA== Date: Fri, 6 Jan 2023 22:00:48 +0000 From: Mark Brown To: William Zhang Cc: Linux SPI List , Broadcom Kernel List , anand.gore@broadcom.com, tomer.yacoby@broadcom.com, dan.beygelman@broadcom.com, joel.peshkin@broadcom.com, f.fainelli@gmail.com, jonas.gorski@gmail.com, kursad.oney@broadcom.com, dregan@mail.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH 11/16] spi: bcm63xx-hsspi: Add prepend feature support Message-ID: References: <20230106200809.330769-1-william.zhang@broadcom.com> <20230106200809.330769-12-william.zhang@broadcom.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="03fzSve1xfjNt8Ya" Content-Disposition: inline In-Reply-To: <20230106200809.330769-12-william.zhang@broadcom.com> X-Cookie: Do not fold, spindle or mutilate. Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --03fzSve1xfjNt8Ya Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Fri, Jan 06, 2023 at 12:08:03PM -0800, William Zhang wrote: > Multiple transfers within a SPI message may be combined into one > transfer to the controller using its prepend feature. A SPI message is > prependable only if the following are all true: > * One or more half duplex write transfer > * Optional full duplex read/write at the end > * No delay and cs_change between transfers There is nothing driver specific here, this should be implemented in the core - we have existing logic to rewrite messages to match driver constraints, this could be added there possibly with flags to allow drivers to disable or enable the merging if they've got special requirements. --03fzSve1xfjNt8Ya Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmO4mg8ACgkQJNaLcl1U h9ACJwf/UE1spDfA2xj1/PcQ+u3EwHKl083wfkb2q6wwMJqDHkKLmUA4U8gD5dU8 /vZWPViLit19LVtn/P/v7n4yhwR4iks3mYnQKcvV9s88QKsuoY1hgfi4362VdbKf bqciz2t2WhxEu1eGFjYpdEazyEHH+OkzFJDIGgdsYM+s1CLq1R1PCIPB3KFeIopW 5N2gk+83IHLPqNvHp5RM+fdU5kPv6tKLtcAoJO+0eI1HvOGs25Cp7wI7hgtOSR+V XozRJNL3Nd9TYjvIGJvatNMWACBZ5Xo7h9GHhVxUWNzWvJk5g8GmTvRJS97rBQOT 5WgghfpwqkekaGIzRkCHfjEx4LFs6w== =M+9u -----END PGP SIGNATURE----- --03fzSve1xfjNt8Ya--