From patchwork Wed Apr 29 07:21:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandru Ardelean X-Patchwork-Id: 11516123 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 71E471575 for ; Wed, 29 Apr 2020 07:21:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6307520787 for ; Wed, 29 Apr 2020 07:21:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726401AbgD2HVV (ORCPT ); Wed, 29 Apr 2020 03:21:21 -0400 Received: from mx0a-00128a01.pphosted.com ([148.163.135.77]:8564 "EHLO mx0a-00128a01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726386AbgD2HVV (ORCPT ); Wed, 29 Apr 2020 03:21:21 -0400 Received: from pps.filterd (m0167088.ppops.net [127.0.0.1]) by mx0a-00128a01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 03T7FcRf029194; Wed, 29 Apr 2020 03:21:18 -0400 Received: from nwd2mta3.analog.com ([137.71.173.56]) by mx0a-00128a01.pphosted.com with ESMTP id 30pes2c83a-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 29 Apr 2020 03:21:18 -0400 Received: from SCSQMBX11.ad.analog.com (scsqmbx11.ad.analog.com [10.77.17.10]) by nwd2mta3.analog.com (8.14.7/8.14.7) with ESMTP id 03T7LGc3060520 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=FAIL); Wed, 29 Apr 2020 03:21:16 -0400 Received: from SCSQMBX11.ad.analog.com (10.77.17.10) by SCSQMBX11.ad.analog.com (10.77.17.10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1779.2; Wed, 29 Apr 2020 00:21:15 -0700 Received: from zeus.spd.analog.com (10.64.82.11) by SCSQMBX11.ad.analog.com (10.77.17.10) with Microsoft SMTP Server id 15.1.1779.2 via Frontend Transport; Wed, 29 Apr 2020 00:21:15 -0700 Received: from localhost.localdomain ([10.48.65.12]) by zeus.spd.analog.com (8.15.1/8.15.1) with ESMTP id 03T7LCcS006213; Wed, 29 Apr 2020 03:21:12 -0400 From: Alexandru Ardelean To: , , CC: , , Dragos Bogdan , Alexandru Ardelean Subject: [PATCH] staging: iio: ad2s1210: Fix SPI reading Date: Wed, 29 Apr 2020 10:21:29 +0300 Message-ID: <20200429072129.81504-1-alexandru.ardelean@analog.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 X-ADIRoutedOnPrem: True X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.676 definitions=2020-04-29_02:2020-04-28,2020-04-29 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 spamscore=0 mlxscore=0 suspectscore=0 bulkscore=0 phishscore=0 priorityscore=1501 clxscore=1015 malwarescore=0 impostorscore=0 lowpriorityscore=0 mlxlogscore=960 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004290059 Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org From: Dragos Bogdan If the serial interface is used, the 8-bit address should be latched using the rising edge of the WR/FSYNC signal. This basically means that a CS change is required between the first byte sent, and the second one. This change splits the single-transfer transfer of 2 bytes into 2 transfers with a single byte, and CS change in-between. Signed-off-by: Dragos Bogdan Signed-off-by: Alexandru Ardelean --- drivers/staging/iio/resolver/ad2s1210.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/drivers/staging/iio/resolver/ad2s1210.c b/drivers/staging/iio/resolver/ad2s1210.c index 4b25a3a314ed..ed404355ea4c 100644 --- a/drivers/staging/iio/resolver/ad2s1210.c +++ b/drivers/staging/iio/resolver/ad2s1210.c @@ -130,17 +130,24 @@ static int ad2s1210_config_write(struct ad2s1210_state *st, u8 data) static int ad2s1210_config_read(struct ad2s1210_state *st, unsigned char address) { - struct spi_transfer xfer = { - .len = 2, - .rx_buf = st->rx, - .tx_buf = st->tx, + struct spi_transfer xfers[] = { + { + .len = 1, + .rx_buf = &st->rx[0], + .tx_buf = &st->tx[0], + .cs_change = 1, + }, { + .len = 1, + .rx_buf = &st->rx[1], + .tx_buf = &st->tx[1], + }, }; int ret = 0; ad2s1210_set_mode(MOD_CONFIG, st); st->tx[0] = address | AD2S1210_MSB_IS_HIGH; st->tx[1] = AD2S1210_REG_FAULT; - ret = spi_sync_transfer(st->sdev, &xfer, 1); + ret = spi_sync_transfer(st->sdev, xfers, 2); if (ret < 0) return ret;