From patchwork Sun Jun 26 19:42:43 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Walle X-Patchwork-Id: 12895894 X-Patchwork-Delegate: kuba@kernel.org 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 B8DD2CCA47C for ; Sun, 26 Jun 2022 19:42:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230004AbiFZTm5 (ORCPT ); Sun, 26 Jun 2022 15:42:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43720 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229492AbiFZTmz (ORCPT ); Sun, 26 Jun 2022 15:42:55 -0400 Received: from ssl.serverraum.org (ssl.serverraum.org [IPv6:2a01:4f8:151:8464::1:2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0B273208; Sun, 26 Jun 2022 12:42:53 -0700 (PDT) Received: from mwalle01.kontron.local. (unknown [213.135.10.150]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ssl.serverraum.org (Postfix) with ESMTPSA id A327922248; Sun, 26 Jun 2022 21:42:51 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1656272571; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=DG1TtMgcwFPG6kIPYW21bB1MOFqKbpqr3fn3fLeFTcU=; b=TSj13tGk7jUP8vRP1Keg1Griw5QTYTnm7tjZixfTJWAaz481wHvxRxCZ/EaaRMXQRGW6AK 9PkFzlr8jpnOL9mthTHK+LSt6NGempahXaef/Ljcue9YYJ2yeYhm7s8uSjSp6NwLwJQ2UX IwaeqsdgHG+MjZp1iEsFeHu+CirzN1U= From: Michael Walle To: Charles Gorand , Krzysztof Kozlowski Cc: =?utf-8?q?Cl=C3=A9ment_Perrochaud?= , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Michael Walle Subject: [PATCH 2/2] NFC: nxp-nci: Don't issue a zero length i2c_master_read() Date: Sun, 26 Jun 2022 21:42:43 +0200 Message-Id: <20220626194243.4059870-2-michael@walle.cc> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220626194243.4059870-1-michael@walle.cc> References: <20220626194243.4059870-1-michael@walle.cc> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org There are packets which doesn't have a payload. In that case, the second i2c_master_read() will have a zero length. But because the NFC controller doesn't have any data left, it will NACK the I2C read and -ENXIO will be returned. In case there is no payload, just skip the second i2c master read. Fixes: 6be88670fc59 ("NFC: nxp-nci_i2c: Add I2C support to NXP NCI driver") Signed-off-by: Michael Walle Reviewed-by: Krzysztof Kozlowski --- drivers/nfc/nxp-nci/i2c.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/nfc/nxp-nci/i2c.c b/drivers/nfc/nxp-nci/i2c.c index 9c80d5a6d56b..c9361b5249b7 100644 --- a/drivers/nfc/nxp-nci/i2c.c +++ b/drivers/nfc/nxp-nci/i2c.c @@ -162,6 +162,9 @@ static int nxp_nci_i2c_nci_read(struct nxp_nci_i2c_phy *phy, skb_put_data(*skb, (void *)&header, NCI_CTRL_HDR_SIZE); + if (!header.plen) + return 0; + r = i2c_master_recv(client, skb_put(*skb, header.plen), header.plen); if (r < 0) { nfc_err(&client->dev, "I2C receive error %pe\n", ERR_PTR(r));