From patchwork Thu Dec 17 20:28:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sowjanya Komatineni X-Patchwork-Id: 11980763 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ECF1FC3526E for ; Thu, 17 Dec 2020 20:30:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CD90823A40 for ; Thu, 17 Dec 2020 20:30:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731528AbgLQU3j (ORCPT ); Thu, 17 Dec 2020 15:29:39 -0500 Received: from hqnvemgate26.nvidia.com ([216.228.121.65]:19869 "EHLO hqnvemgate26.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731502AbgLQU3h (ORCPT ); Thu, 17 Dec 2020 15:29:37 -0500 Received: from hqmail.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate26.nvidia.com (using TLS: TLSv1.2, AES256-SHA) id ; Thu, 17 Dec 2020 12:28:56 -0800 Received: from HQMAIL107.nvidia.com (172.20.187.13) by HQMAIL105.nvidia.com (172.20.187.12) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Thu, 17 Dec 2020 20:28:55 +0000 Received: from skomatineni-linux.nvidia.com (172.20.145.6) by mail.nvidia.com (172.20.187.13) with Microsoft SMTP Server id 15.0.1473.3 via Frontend Transport; Thu, 17 Dec 2020 20:28:55 +0000 From: Sowjanya Komatineni To: , , , , CC: , , , , , , , Subject: [PATCH v4 5/9] spi: spi-mem: Mark dummy transfers by setting dummy_data bit Date: Thu, 17 Dec 2020 12:28:43 -0800 Message-ID: <1608236927-28701-6-git-send-email-skomatineni@nvidia.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1608236927-28701-1-git-send-email-skomatineni@nvidia.com> References: <1608236927-28701-1-git-send-email-skomatineni@nvidia.com> X-NVConfidentiality: public MIME-Version: 1.0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1608236936; bh=6bx+wsy3UKNOmMAtBxcV/nZjihJYWCwQ1WcNk7bO2Rk=; h=From:To:CC:Subject:Date:Message-ID:X-Mailer:In-Reply-To: References:X-NVConfidentiality:MIME-Version:Content-Type; b=j25WETWPEcNmnfRW25FUg0M7YNjCw4fVT8t0fIlh+cwCnKYzmoBMce/if8y3vp1mB Fx+3Z+pHJOP9PX6PQ4hlyqnBVrIE7c+32CLL3n/6GK3LbomFg1hqUa5ZI2vy5k76V1 l8uwwmYJ/R7g2RhOkuKoBoQr5GR1sjfAYQhBZTIwFOt7REPp+8ghlnN0XjK+azDJa8 FN7B/ePdECFzX3JAjomVMhkmUHyEFt9YTm+3gV4NOLpEszmtaT80xKiQI6+Vrrhjtk JIwx6dZUMMHhOeaN4fXtFM1Qde0EnsnntlbDN8/vSsbUHgkzktf86ewvN0XJ3Kp2U4 SQ2nYTLdmXOaQ== Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org This patch marks dummy transfer by setting dummy_data bit to 1. Controllers supporting dummy transfer by hardware use this bit field to skip software transfer of dummy bytes and use hardware dummy bytes transfer. Signed-off-by: Sowjanya Komatineni --- drivers/spi/spi-mem.c | 1 + include/linux/spi/spi.h | 2 ++ 2 files changed, 3 insertions(+) diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c index f3a3f19..c64371c 100644 --- a/drivers/spi/spi-mem.c +++ b/drivers/spi/spi-mem.c @@ -354,6 +354,7 @@ int spi_mem_exec_op(struct spi_mem *mem, const struct spi_mem_op *op) xfers[xferpos].tx_buf = tmpbuf + op->addr.nbytes + 1; xfers[xferpos].len = op->dummy.nbytes; xfers[xferpos].tx_nbits = op->dummy.buswidth; + xfers[xferpos].dummy_data = 1; spi_message_add_tail(&xfers[xferpos], &msg); xferpos++; totalxferlen += op->dummy.nbytes; diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index aa09fdc..708f2f5 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -827,6 +827,7 @@ extern void spi_res_release(struct spi_controller *ctlr, * transfer. If 0 the default (from @spi_device) is used. * @bits_per_word: select a bits_per_word other than the device default * for this transfer. If 0 the default (from @spi_device) is used. + * @dummy_data: indicates transfer is dummy bytes transfer. * @cs_change: affects chipselect after this transfer completes * @cs_change_delay: delay between cs deassert and assert when * @cs_change is set and @spi_transfer is not the last in @spi_message @@ -939,6 +940,7 @@ struct spi_transfer { struct sg_table tx_sg; struct sg_table rx_sg; + unsigned dummy_data:1; unsigned cs_change:1; unsigned tx_nbits:3; unsigned rx_nbits:3;