From patchwork Mon Apr 13 08:20:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandru Ardelean X-Patchwork-Id: 11485285 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 18C651392 for ; Mon, 13 Apr 2020 08:36:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 056AA20737 for ; Mon, 13 Apr 2020 08:36:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727123AbgDMIf1 (ORCPT ); Mon, 13 Apr 2020 04:35:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.18]:42904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728250AbgDMIUT (ORCPT ); Mon, 13 Apr 2020 04:20:19 -0400 Received: from mx0a-00128a01.pphosted.com (mx0a-00128a01.pphosted.com [148.163.135.77]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 90A17C00860B; Mon, 13 Apr 2020 01:20:19 -0700 (PDT) Received: from pps.filterd (m0167089.ppops.net [127.0.0.1]) by mx0a-00128a01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 03D8IJsC003744; Mon, 13 Apr 2020 04:20:19 -0400 Received: from nwd2mta4.analog.com ([137.71.173.58]) by mx0a-00128a01.pphosted.com with ESMTP id 30bat4p92s-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 13 Apr 2020 04:20:19 -0400 Received: from SCSQMBX11.ad.analog.com (scsqmbx11.ad.analog.com [10.77.17.10]) by nwd2mta4.analog.com (8.14.7/8.14.7) with ESMTP id 03D8KHXT020286 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=FAIL); Mon, 13 Apr 2020 04:20:17 -0400 Received: from SCSQMBX10.ad.analog.com (10.77.17.5) 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; Mon, 13 Apr 2020 01:20:16 -0700 Received: from zeus.spd.analog.com (10.64.82.11) by SCSQMBX10.ad.analog.com (10.77.17.5) with Microsoft SMTP Server id 15.1.1779.2 via Frontend Transport; Mon, 13 Apr 2020 01:20:15 -0700 Received: from localhost.localdomain ([10.48.65.12]) by zeus.spd.analog.com (8.15.1/8.15.1) with ESMTP id 03D8KEkZ026212; Mon, 13 Apr 2020 04:20:14 -0400 From: Alexandru Ardelean To: , CC: , Alexandru Ardelean Subject: [PATCH v3 1/2] iio: adc: ad7192: fix null pointer de-reference crash during probe Date: Mon, 13 Apr 2020 11:20:43 +0300 Message-ID: <20200413082044.81101-1-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=2020-04-13_02:2020-04-12,2020-04-13 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 spamscore=0 lowpriorityscore=0 priorityscore=1501 clxscore=1015 adultscore=0 mlxlogscore=999 bulkscore=0 malwarescore=0 phishscore=0 suspectscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004130074 Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org When the 'spi_device_id' table was removed, it omitted to cleanup/fix the assignment: 'indio_dev->name = spi_get_device_id(spi)->name;' After that patch 'spi_get_device_id(spi)' returns NULL, so this crashes during probe with null de-ref. This change fixes this by introducing an ad7192_chip_info struct, and defines all part-names [that should be assigned to indio_dev->name] in a 'ad7192_chip_info_tbl' table. With this change, the old 'st->devid' is also moved to be a 'chip_info->chip_id'. And the old 'ID_AD719X' macros have been renamed to 'CHIPID_AD719X'. Tld identifiers have been re-purposed to be enum/index values in the new 'ad7192_chip_info_tbl'. This should fix the bug, and maintain the ABI for the 'indio_dev->name' field. Fixes: 66614ab2be38 ("staging: iio: adc: ad7192: removed spi_device_id") Signed-off-by: Alexandru Ardelean --- Changelog v2 -> v3: * reworked patch to introduce a chip_info struct for the part-name * added 2nd patch to move of-table closer to the end of the file; this patch is more cosmetic; has no fixes tag, but is on top of the previous Changelog v1 -> v2: * fix colon for Fixes tag * updated commit title a bit; to make it longer drivers/iio/adc/ad7192.c | 61 ++++++++++++++++++++++++++++++---------- 1 file changed, 46 insertions(+), 15 deletions(-) diff --git a/drivers/iio/adc/ad7192.c b/drivers/iio/adc/ad7192.c index 8ec28aa8fa8a..7e8662c5cb0e 100644 --- a/drivers/iio/adc/ad7192.c +++ b/drivers/iio/adc/ad7192.c @@ -125,10 +125,10 @@ #define AD7193_CH_AINCOM 0x600 /* AINCOM - AINCOM */ /* ID Register Bit Designations (AD7192_REG_ID) */ -#define ID_AD7190 0x4 -#define ID_AD7192 0x0 -#define ID_AD7193 0x2 -#define ID_AD7195 0x6 +#define CHIPID_AD7190 0x4 +#define CHIPID_AD7192 0x0 +#define CHIPID_AD7193 0x2 +#define CHIPID_AD7195 0x6 #define AD7192_ID_MASK 0x0F /* GPOCON Register Bit Designations (AD7192_REG_GPOCON) */ @@ -161,7 +161,20 @@ enum { AD7192_SYSCALIB_FULL_SCALE, }; +enum { + ID_AD7190, + ID_AD7192, + ID_AD7193, + ID_AD7195, +}; + +struct ad7192_chip_info { + unsigned int chip_id; + const char *name; +}; + struct ad7192_state { + const struct ad7192_chip_info *chip_info; struct regulator *avdd; struct regulator *dvdd; struct clk *mclk; @@ -172,7 +185,6 @@ struct ad7192_state { u32 conf; u32 scale_avail[8][2]; u8 gpocon; - u8 devid; u8 clock_sel; struct mutex lock; /* protect sensor state */ u8 syscalib_mode[8]; @@ -348,7 +360,7 @@ static int ad7192_setup(struct ad7192_state *st, struct device_node *np) id &= AD7192_ID_MASK; - if (id != st->devid) + if (id != st->chip_info->chip_id) dev_warn(&st->sd.spi->dev, "device ID query failed (0x%X)\n", id); @@ -363,7 +375,7 @@ static int ad7192_setup(struct ad7192_state *st, struct device_node *np) st->mode |= AD7192_MODE_REJ60; refin2_en = of_property_read_bool(np, "adi,refin2-pins-enable"); - if (refin2_en && st->devid != ID_AD7195) + if (refin2_en && st->chip_info->chip_id != CHIPID_AD7195) st->conf |= AD7192_CONF_REFSEL; st->conf &= ~AD7192_CONF_CHOP; @@ -859,11 +871,30 @@ static const struct iio_chan_spec ad7193_channels[] = { IIO_CHAN_SOFT_TIMESTAMP(14), }; +static const struct ad7192_chip_info ad7192_chip_info_tbl[] = { + [ID_AD7190] = { + .chip_id = CHIPID_AD7190, + .name = "ad7190", + }, + [ID_AD7192] = { + .chip_id = CHIPID_AD7192, + .name = "ad7192", + }, + [ID_AD7193] = { + .chip_id = CHIPID_AD7193, + .name = "ad7193", + }, + [ID_AD7195] = { + .chip_id = CHIPID_AD7195, + .name = "ad7195", + }, +}; + static int ad7192_channels_config(struct iio_dev *indio_dev) { struct ad7192_state *st = iio_priv(indio_dev); - switch (st->devid) { + switch (st->chip_info->chip_id) { case ID_AD7193: indio_dev->channels = ad7193_channels; indio_dev->num_channels = ARRAY_SIZE(ad7193_channels); @@ -878,10 +909,10 @@ static int ad7192_channels_config(struct iio_dev *indio_dev) } static const struct of_device_id ad7192_of_match[] = { - { .compatible = "adi,ad7190", .data = (void *)ID_AD7190 }, - { .compatible = "adi,ad7192", .data = (void *)ID_AD7192 }, - { .compatible = "adi,ad7193", .data = (void *)ID_AD7193 }, - { .compatible = "adi,ad7195", .data = (void *)ID_AD7195 }, + { .compatible = "adi,ad7190", .data = &ad7192_chip_info_tbl[ID_AD7190] }, + { .compatible = "adi,ad7192", .data = &ad7192_chip_info_tbl[ID_AD7192] }, + { .compatible = "adi,ad7193", .data = &ad7192_chip_info_tbl[ID_AD7193] }, + { .compatible = "adi,ad7195", .data = &ad7192_chip_info_tbl[ID_AD7195] }, {} }; MODULE_DEVICE_TABLE(of, ad7192_of_match); @@ -938,16 +969,16 @@ static int ad7192_probe(struct spi_device *spi) } spi_set_drvdata(spi, indio_dev); - st->devid = (unsigned long)of_device_get_match_data(&spi->dev); + st->chip_info = of_device_get_match_data(&spi->dev); indio_dev->dev.parent = &spi->dev; - indio_dev->name = spi_get_device_id(spi)->name; + indio_dev->name = st->chip_info->name; indio_dev->modes = INDIO_DIRECT_MODE; ret = ad7192_channels_config(indio_dev); if (ret < 0) goto error_disable_dvdd; - if (st->devid == ID_AD7195) + if (st->chip_info->chip_id == CHIPID_AD7195) indio_dev->info = &ad7195_info; else indio_dev->info = &ad7192_info;