From patchwork Thu Jan 7 11:20:49 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandru Ardelean X-Patchwork-Id: 12003589 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 00A91C433DB for ; Thu, 7 Jan 2021 11:18:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD4272223E for ; Thu, 7 Jan 2021 11:18:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727451AbhAGLSM (ORCPT ); Thu, 7 Jan 2021 06:18:12 -0500 Received: from mx0a-00128a01.pphosted.com ([148.163.135.77]:51396 "EHLO mx0a-00128a01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727252AbhAGLSL (ORCPT ); Thu, 7 Jan 2021 06:18:11 -0500 Received: from pps.filterd (m0167088.ppops.net [127.0.0.1]) by mx0a-00128a01.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 107BEgnW009880; Thu, 7 Jan 2021 06:17:17 -0500 Received: from nwd2mta4.analog.com ([137.71.173.58]) by mx0a-00128a01.pphosted.com with ESMTP id 35wsv6h0ym-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 07 Jan 2021 06:17:17 -0500 Received: from ASHBMBX9.ad.analog.com (ASHBMBX9.ad.analog.com [10.64.17.10]) by nwd2mta4.analog.com (8.14.7/8.14.7) with ESMTP id 107BHGWq024814 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=FAIL); Thu, 7 Jan 2021 06:17:16 -0500 Received: from ASHBCASHYB5.ad.analog.com (10.64.17.133) by ASHBMBX9.ad.analog.com (10.64.17.10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1779.2; Thu, 7 Jan 2021 06:17:15 -0500 Received: from ASHBMBX9.ad.analog.com (10.64.17.10) by ASHBCASHYB5.ad.analog.com (10.64.17.133) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.2.721.2; Thu, 7 Jan 2021 06:17:15 -0500 Received: from zeus.spd.analog.com (10.66.68.11) by ASHBMBX9.ad.analog.com (10.64.17.10) with Microsoft SMTP Server id 15.1.1779.2 via Frontend Transport; Thu, 7 Jan 2021 06:17:15 -0500 Received: from localhost.localdomain ([10.48.65.12]) by zeus.spd.analog.com (8.15.1/8.15.1) with ESMTP id 107BHDpq015369; Thu, 7 Jan 2021 06:17:13 -0500 From: Alexandru Ardelean To: , CC: , , , Alexandru Ardelean Subject: [PATCH v8] iio: Handle enumerated properties with gaps Date: Thu, 7 Jan 2021 13:20:49 +0200 Message-ID: <20210107112049.10815-1-alexandru.ardelean@analog.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 X-ADIRuleOP-NewSCL: Rule Triggered X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.343,18.0.737 definitions=2021-01-07_05:2021-01-07,2021-01-07 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 phishscore=0 impostorscore=0 malwarescore=0 mlxlogscore=965 mlxscore=0 adultscore=0 suspectscore=0 bulkscore=0 spamscore=0 priorityscore=1501 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2101070069 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org From: Lars-Peter Clausen Some enums might have gaps or reserved values in the middle of their value range. E.g. consider a 2-bit enum where the values 0, 1 and 3 have a meaning, but 2 is a reserved value and can not be used. Add support for such enums to the IIO enum helper functions. A reserved values is marked by setting its entry in the items array to NULL rather than the normal descriptive string value. Signed-off-by: Lars-Peter Clausen Signed-off-by: Alexandru Ardelean Reviewed-by: Andy Shevchenko --- Changelog v7 -> v8: * https://lore.kernel.org/linux-iio/20210107084434.35283-1-alexandru.ardelean@analog.com/ * dropped patch 'lib/string.c: add __sysfs_match_string_with_gaps() helper' * merged __sysfs_match_string_with_gaps into drivers/iio/industrial-core.c as iio_sysfs_match_string_with_gaps() drivers/iio/industrialio-core.c | 39 ++++++++++++++++++++++++++++++--- 1 file changed, 36 insertions(+), 3 deletions(-) diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index e9ee9363fed0..db20e2ab437d 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -169,6 +169,36 @@ static const char * const iio_chan_info_postfix[] = { [IIO_CHAN_INFO_CALIBAMBIENT] = "calibambient", }; +/** + * iio_sysfs_match_string_with_gaps - matches given string in an array with gaps + * @array: array of strings + * @n: number of strings in the array + * @str: string to match with + * + * Returns index of @str in the @array or -EINVAL, similar to match_string(). + * Uses sysfs_streq instead of strcmp for matching. + * + * This routine will look for a string in an array of strings. + * The search will continue until the element is found or the n-th element + * is reached, regardless of any NULL elements in the array. + */ +static int iio_sysfs_match_string_with_gaps(const char * const *array, size_t n, + const char *str) +{ + const char *item; + int index; + + for (index = 0; index < n; index++) { + item = array[index]; + if (!item) + continue; + if (sysfs_streq(item, str)) + return index; + } + + return -EINVAL; +} + #if defined(CONFIG_DEBUG_FS) /* * There's also a CONFIG_DEBUG_FS guard in include/linux/iio/iio.h for @@ -470,8 +500,11 @@ ssize_t iio_enum_available_read(struct iio_dev *indio_dev, if (!e->num_items) return 0; - for (i = 0; i < e->num_items; ++i) + for (i = 0; i < e->num_items; ++i) { + if (!e->items[i]) + continue; len += scnprintf(buf + len, PAGE_SIZE - len, "%s ", e->items[i]); + } /* replace last space with a newline */ buf[len - 1] = '\n'; @@ -492,7 +525,7 @@ ssize_t iio_enum_read(struct iio_dev *indio_dev, i = e->get(indio_dev, chan); if (i < 0) return i; - else if (i >= e->num_items) + else if (i >= e->num_items || !e->items[i]) return -EINVAL; return snprintf(buf, PAGE_SIZE, "%s\n", e->items[i]); @@ -509,7 +542,7 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev, if (!e->set) return -EINVAL; - ret = __sysfs_match_string(e->items, e->num_items, buf); + ret = iio_sysfs_match_string_with_gaps(e->items, e->num_items, buf); if (ret < 0) return ret;