From patchwork Tue Sep 28 19:55:48 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pekka Korpinen X-Patchwork-Id: 12523687 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C0F11C433EF for ; Tue, 28 Sep 2021 19:57:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 95A9361139 for ; Tue, 28 Sep 2021 19:57:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242470AbhI1T6k (ORCPT ); Tue, 28 Sep 2021 15:58:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44266 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242525AbhI1T6k (ORCPT ); Tue, 28 Sep 2021 15:58:40 -0400 Received: from lahtoruutu.iki.fi (lahtoruutu.iki.fi [IPv6:2a0b:5c81:1c1::37]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3C5EEC06161C; Tue, 28 Sep 2021 12:57:00 -0700 (PDT) Received: from groot.intra.skream.org (mobile-user-2e84bb-13.dhcp.inet.fi [46.132.187.13]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: pekka.korpinen) by lahtoruutu.iki.fi (Postfix) with ESMTPSA id 5DCBA1B001C6; Tue, 28 Sep 2021 22:56:54 +0300 (EEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=iki.fi; s=lahtoruutu; t=1632859014; 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; bh=0Pv7C2sMIx0ey5J4LhX0/v7PZ370uBe7XXywiIOBNGQ=; b=N5cdWZo5f0iZhZCl48laTsYsGQUaLOkwDmp3HcAa/N4DvnvHcscGWgyQlQeomkLKmsRLSB vrz3pG6UDEg91gLwLy3ePX8TgrqV51xQMKnOht5+XqAefMiNY+AjFxFMZGKgxqR+itNbCH 7fAAYdYjsFtxfBGWNCcbxseH8P/bcaZLgxV5YCe/8RocwILET9EGZcRINystQ0zYAOhrV0 7ZC8MtVo0mRmxYgf7qZeSjdtrQ5LZMCcrSqQ7gDibWfDooFGn5+h6U1Jklano/bEWN2REM OzK8O096WVUwIE7L9+hMuz055Ue+JQt8fUZ9yIC7nAGY2XD8eK5HzPphNRp8YQ== From: Pekka Korpinen Cc: Pekka Korpinen , Lars-Peter Clausen , Michael Hennerich , Jonathan Cameron , linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] iio: dac: ad5446: Fix ad5622_write() return value Date: Tue, 28 Sep 2021 22:55:48 +0300 Message-Id: <20210928195548.17846-1-pekka.korpinen@iki.fi> X-Mailer: git-send-email 2.33.0 MIME-Version: 1.0 ARC-Seal: i=1; s=lahtoruutu; d=iki.fi; t=1632859014; a=rsa-sha256; cv=none; b=leupTbo/KG6HZyN/d+683TfdU7qJ6HyyJl/bz6ptXNZt1niXAvQcwv3LsfKWXoWG+ZHeTs 01wZuHBQHClSSCR0QZBcpiCQzb3J7aDSOysENtao0cZKRLNnZqLumN1Rf6KaWii8QjiWUu VhFja23DQJx+LVE9H21+4d7pofc3jEhKduh/tcae2dl2C8Ht4I1j+dOPzxmpIgWe49W3ji xUMV0fe4HhH5qo2i8L6ofcSkOazENSQcfbThf4XcFZIRnO/0LGTV1iktEzv4YpDNFoLEUZ kYa658LvYpma3zA2fv6BXdOTO5IiDRJrr2N5S3ZhdXb8vQrwl2N1cvmQZFM2iw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=iki.fi; s=lahtoruutu; t=1632859014; 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; bh=0Pv7C2sMIx0ey5J4LhX0/v7PZ370uBe7XXywiIOBNGQ=; b=KQOImEur8j3QAA7RgVuLK2oXMbojnO7ErjPgEJC13ZhMm1rKnlkEzFxGBigIwSyyyfcRCv wWUoxu2PvFcXb2woQGzYfPb5mg1+JQZyCMI9i5JyDaEXgUugFk8SnOGJ+P2jsfpKlcCdRU iF+F+ZFNPvvBH1Nzy9yN41N3SjEjtwRGTZgtKw9lthBqs3qWilUSsWwSBBVZ9FpC31rEd+ aK14cwS9ZqNUXDOC3X9Ucc4POOwY3KDck9euCoUAvGA21EOYKyAKIgONNRYkk97FRWpl9z lBpsCdLgq/44u7J1/BX7FUuC3FOOigKISYw7QtJ7onboUspujj5GUBUOV40Kmg== ARC-Authentication-Results: i=1; ORIGINATING; auth=pass smtp.auth=pekka.korpinen smtp.mailfrom=pekka.korpinen@iki.fi To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On success i2c_master_send() returns the number of bytes written. The call from iio_write_channel_info(), however, expects the return value to be zero on success. Signed-off-by: Pekka Korpinen Reviewed-by: Alexandru Ardelean --- This bug causes incorrect consumption of the sysfs buffer in iio_write_channel_info(). When writing more than two characters to out_voltage0_raw, the ad5446 write handler is called multiple times causing unexpected behavior. A similar fix was applied for ad5064.c in 2015 - commit 03fe472ef33b ("iio:ad5064: Make sure ad5064_i2c_write() returns 0 on success"). drivers/iio/dac/ad5446.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/iio/dac/ad5446.c b/drivers/iio/dac/ad5446.c index 488ec69967d6..dfd541bbde5b 100644 --- a/drivers/iio/dac/ad5446.c +++ b/drivers/iio/dac/ad5446.c @@ -531,8 +531,13 @@ static int ad5622_write(struct ad5446_state *st, unsigned val) { struct i2c_client *client = to_i2c_client(st->dev); __be16 data = cpu_to_be16(val); + int ret; + + ret = i2c_master_send(client, (char *)&data, sizeof(data)); + if (ret < 0) + return ret; - return i2c_master_send(client, (char *)&data, sizeof(data)); + return 0; } /*