From patchwork Wed May 11 19:27:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eddie James X-Patchwork-Id: 12846569 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 E7212C433EF for ; Wed, 11 May 2022 19:27:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240018AbiEKT1n (ORCPT ); Wed, 11 May 2022 15:27:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53076 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235700AbiEKT1m (ORCPT ); Wed, 11 May 2022 15:27:42 -0400 Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 39D3529815; Wed, 11 May 2022 12:27:41 -0700 (PDT) Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 24BJMw1h020139; Wed, 11 May 2022 19:27:27 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=pp1; bh=/6M2AEQgHJa4lWAvunRHqzAbQynfvz6x3X7NWAp1+MA=; b=GYBXPuuGtsxcKBVUHgsusF/WaPnp2tMVBDPK+jKnvxHZqS+1vbtmkKtei+2onj+iv+UC 7KVLFZ2PD3z7b0oGOrfoh0XkU5ry+jwnuNVVwQSpUpzkQIC6YwA60UHmbq40BQ7z0Pbx fqT8TcSQHWXPkYglDJkDu2rTiyr16LgBW3kMJuVU/HdMht+qGESdJwUbeM96LHeOR/Hy ptRASprMzqpMGgC03ewUVmjNy8Vg2uu/LYwRzZLiBNg92uQyCVplpOsAyGWR5rT/uveP pDk0ZnMZwdUzaNSoAfcNXLzZ+e+F4S6yT0HKXFpEymG91mmxP0+kGZt1sK6U72Y1AAwn GA== Received: from ppma02dal.us.ibm.com (a.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.10]) by mx0b-001b2d01.pphosted.com (PPS) with ESMTPS id 3g0hc3a9c4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 11 May 2022 19:27:26 +0000 Received: from pps.filterd (ppma02dal.us.ibm.com [127.0.0.1]) by ppma02dal.us.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 24BJ8LdG029311; Wed, 11 May 2022 19:27:26 GMT Received: from b01cxnp22034.gho.pok.ibm.com (b01cxnp22034.gho.pok.ibm.com [9.57.198.24]) by ppma02dal.us.ibm.com with ESMTP id 3fwgdanvx1-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 11 May 2022 19:27:26 +0000 Received: from b01ledav003.gho.pok.ibm.com (b01ledav003.gho.pok.ibm.com [9.57.199.108]) by b01cxnp22034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 24BJRPa155771448 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 11 May 2022 19:27:25 GMT Received: from b01ledav003.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7760CB206A; Wed, 11 May 2022 19:27:25 +0000 (GMT) Received: from b01ledav003.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id D1F20B2066; Wed, 11 May 2022 19:27:24 +0000 (GMT) Received: from v0005c16.aus.stglabs.ibm.com (unknown [9.211.61.211]) by b01ledav003.gho.pok.ibm.com (Postfix) with ESMTP; Wed, 11 May 2022 19:27:24 +0000 (GMT) From: Eddie James To: linux-iio@vger.kernel.org Cc: linux-kernel@vger.kernel.org, jic23@kernel.org, lars@metafoo.de, joel@jms.id.au Subject: [PATCH] iio: pressure: dps310: Reset chip if MEAS_CFG is corrupt Date: Wed, 11 May 2022 14:27:24 -0500 Message-Id: <20220511192724.51845-1-eajames@linux.ibm.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: ip7WNvXDMVQ7T0c_D0_xm15yrW3XZmSB X-Proofpoint-ORIG-GUID: ip7WNvXDMVQ7T0c_D0_xm15yrW3XZmSB X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.486,FMLib:17.11.64.514 definitions=2022-05-11_07,2022-05-11_01,2022-02-23_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 mlxlogscore=999 mlxscore=0 adultscore=0 lowpriorityscore=0 phishscore=0 priorityscore=1501 bulkscore=0 spamscore=0 suspectscore=0 clxscore=1015 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2202240000 definitions=main-2205110083 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org Corruption of the MEAS_CFG register has been observed soon after system boot. In order to recover this scenario, check MEAS_CFG if measurement isn't ready, and if it's incorrect, reset the DPS310 and write all the necessary registers. Signed-off-by: Eddie James --- drivers/iio/pressure/dps310.c | 280 +++++++++++++++++++++------------- 1 file changed, 173 insertions(+), 107 deletions(-) diff --git a/drivers/iio/pressure/dps310.c b/drivers/iio/pressure/dps310.c index 36fb7ae0d0a9..39f84614f44e 100644 --- a/drivers/iio/pressure/dps310.c +++ b/drivers/iio/pressure/dps310.c @@ -159,6 +159,106 @@ static int dps310_get_coefs(struct dps310_data *data) return 0; } +/* + * Some verions of chip will read temperatures in the ~60C range when + * its actually ~20C. This is the manufacturer recommended workaround + * to correct the issue. The registers used below are undocumented. + */ +static int dps310_temp_workaround(struct dps310_data *data) +{ + int rc; + int reg; + + rc = regmap_read(data->regmap, 0x32, ®); + if (rc < 0) + return rc; + + /* + * If bit 1 is set then the device is okay, and the workaround does not + * need to be applied + */ + if (reg & BIT(1)) + return 0; + + rc = regmap_write(data->regmap, 0x0e, 0xA5); + if (rc < 0) + return rc; + + rc = regmap_write(data->regmap, 0x0f, 0x96); + if (rc < 0) + return rc; + + rc = regmap_write(data->regmap, 0x62, 0x02); + if (rc < 0) + return rc; + + rc = regmap_write(data->regmap, 0x0e, 0x00); + if (rc < 0) + return rc; + + return regmap_write(data->regmap, 0x0f, 0x00); +} + +static int dps310_startup(struct dps310_data *data) +{ + int rc; + int ready; + + /* + * Set up pressure sensor in single sample, one measurement per second + * mode + */ + rc = regmap_write(data->regmap, DPS310_PRS_CFG, 0); + if (rc < 0) + return rc; + + /* + * Set up external (MEMS) temperature sensor in single sample, one + * measurement per second mode + */ + rc = regmap_write(data->regmap, DPS310_TMP_CFG, DPS310_TMP_EXT); + if (rc < 0) + return rc; + + /* Temp and pressure shifts are disabled when PRC <= 8 */ + rc = regmap_write_bits(data->regmap, DPS310_CFG_REG, + DPS310_PRS_SHIFT_EN | DPS310_TMP_SHIFT_EN, 0); + if (rc < 0) + return rc; + + /* MEAS_CFG doesn't update correctly unless first written with 0 */ + rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG, + DPS310_MEAS_CTRL_BITS, 0); + if (rc < 0) + return rc; + + /* Turn on temperature and pressure measurement in the background */ + rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG, + DPS310_MEAS_CTRL_BITS, DPS310_PRS_EN | + DPS310_TEMP_EN | DPS310_BACKGROUND); + if (rc < 0) + return rc; + + /* + * Calibration coefficients required for reporting temperature. + * They are available 40ms after the device has started + */ + rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready, + ready & DPS310_COEF_RDY, 10000, 40000); + if (rc < 0) + return rc; + + rc = dps310_get_coefs(data); + if (rc < 0) + return rc; + + rc = dps310_temp_workaround(data); + if (rc < 0) + return rc; + + return 0; +} + static int dps310_get_pres_precision(struct dps310_data *data) { int rc; @@ -297,6 +397,38 @@ static int dps310_get_temp_k(struct dps310_data *data) return scale_factors[ilog2(rc)]; } +/* Called with lock held */ +static int dps310_verify_meas_cfg(struct dps310_data *data, int ready_bit) +{ + int en = DPS310_PRS_EN | DPS310_TEMP_EN | DPS310_BACKGROUND; + int meas_cfg; + int rc = regmap_read(data->regmap, DPS310_MEAS_CFG, &meas_cfg); + + if (rc < 0) + return rc; + + if (meas_cfg & ready_bit) + return 0; + + if ((meas_cfg & en) != en) { + /* DPS310 register state corrupt, better start from scratch */ + rc = regmap_write(data->regmap, DPS310_RESET, DPS310_RESET_MAGIC); + if (rc < 0) + return rc; + + /* Wait for device chip access: 2.5ms in specification */ + usleep_range(2500, 12000); + rc = dps310_startup(data); + if (rc) + return rc; + + dev_info(&data->client->dev, + "recovered from corrupted MEAS_CFG=%02x\n", meas_cfg); + } + + return 1; +} + static int dps310_read_pres_raw(struct dps310_data *data) { int rc; @@ -309,15 +441,25 @@ static int dps310_read_pres_raw(struct dps310_data *data) if (mutex_lock_interruptible(&data->lock)) return -EINTR; - rate = dps310_get_pres_samp_freq(data); - timeout = DPS310_POLL_TIMEOUT_US(rate); - - /* Poll for sensor readiness; base the timeout upon the sample rate. */ - rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready, - ready & DPS310_PRS_RDY, - DPS310_POLL_SLEEP_US(timeout), timeout); - if (rc) - goto done; + rc = dps310_verify_meas_cfg(data, DPS310_PRS_RDY); + if (rc) { + if (rc < 0) + goto done; + + rate = dps310_get_pres_samp_freq(data); + timeout = DPS310_POLL_TIMEOUT_US(rate); + + /* + * Poll for sensor readiness; base the timeout upon the sample + * rate. + */ + rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, + ready, ready & DPS310_PRS_RDY, + DPS310_POLL_SLEEP_US(timeout), + timeout); + if (rc) + goto done; + } rc = regmap_bulk_read(data->regmap, DPS310_PRS_BASE, val, sizeof(val)); if (rc < 0) @@ -358,15 +500,25 @@ static int dps310_read_temp_raw(struct dps310_data *data) if (mutex_lock_interruptible(&data->lock)) return -EINTR; - rate = dps310_get_temp_samp_freq(data); - timeout = DPS310_POLL_TIMEOUT_US(rate); - - /* Poll for sensor readiness; base the timeout upon the sample rate. */ - rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready, - ready & DPS310_TMP_RDY, - DPS310_POLL_SLEEP_US(timeout), timeout); - if (rc < 0) - goto done; + rc = dps310_verify_meas_cfg(data, DPS310_TMP_RDY); + if (rc) { + if (rc < 0) + goto done; + + rate = dps310_get_temp_samp_freq(data); + timeout = DPS310_POLL_TIMEOUT_US(rate); + + /* + * Poll for sensor readiness; base the timeout upon the sample + * rate. + */ + rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, + ready, ready & DPS310_TMP_RDY, + DPS310_POLL_SLEEP_US(timeout), + timeout); + if (rc < 0) + goto done; + } rc = dps310_read_temp_ready(data); @@ -677,52 +829,12 @@ static const struct iio_info dps310_info = { .write_raw = dps310_write_raw, }; -/* - * Some verions of chip will read temperatures in the ~60C range when - * its actually ~20C. This is the manufacturer recommended workaround - * to correct the issue. The registers used below are undocumented. - */ -static int dps310_temp_workaround(struct dps310_data *data) -{ - int rc; - int reg; - - rc = regmap_read(data->regmap, 0x32, ®); - if (rc < 0) - return rc; - - /* - * If bit 1 is set then the device is okay, and the workaround does not - * need to be applied - */ - if (reg & BIT(1)) - return 0; - - rc = regmap_write(data->regmap, 0x0e, 0xA5); - if (rc < 0) - return rc; - - rc = regmap_write(data->regmap, 0x0f, 0x96); - if (rc < 0) - return rc; - - rc = regmap_write(data->regmap, 0x62, 0x02); - if (rc < 0) - return rc; - - rc = regmap_write(data->regmap, 0x0e, 0x00); - if (rc < 0) - return rc; - - return regmap_write(data->regmap, 0x0f, 0x00); -} - static int dps310_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct dps310_data *data; struct iio_dev *iio; - int rc, ready; + int rc; iio = devm_iio_device_alloc(&client->dev, sizeof(*data)); if (!iio) @@ -747,54 +859,8 @@ static int dps310_probe(struct i2c_client *client, if (rc) return rc; - /* - * Set up pressure sensor in single sample, one measurement per second - * mode - */ - rc = regmap_write(data->regmap, DPS310_PRS_CFG, 0); - - /* - * Set up external (MEMS) temperature sensor in single sample, one - * measurement per second mode - */ - rc = regmap_write(data->regmap, DPS310_TMP_CFG, DPS310_TMP_EXT); - if (rc < 0) - return rc; - - /* Temp and pressure shifts are disabled when PRC <= 8 */ - rc = regmap_write_bits(data->regmap, DPS310_CFG_REG, - DPS310_PRS_SHIFT_EN | DPS310_TMP_SHIFT_EN, 0); - if (rc < 0) - return rc; - - /* MEAS_CFG doesn't update correctly unless first written with 0 */ - rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG, - DPS310_MEAS_CTRL_BITS, 0); - if (rc < 0) - return rc; - - /* Turn on temperature and pressure measurement in the background */ - rc = regmap_write_bits(data->regmap, DPS310_MEAS_CFG, - DPS310_MEAS_CTRL_BITS, DPS310_PRS_EN | - DPS310_TEMP_EN | DPS310_BACKGROUND); - if (rc < 0) - return rc; - - /* - * Calibration coefficients required for reporting temperature. - * They are available 40ms after the device has started - */ - rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG, ready, - ready & DPS310_COEF_RDY, 10000, 40000); - if (rc < 0) - return rc; - - rc = dps310_get_coefs(data); - if (rc < 0) - return rc; - - rc = dps310_temp_workaround(data); - if (rc < 0) + rc = dps310_startup(data); + if (rc) return rc; rc = devm_iio_device_register(&client->dev, iio);