From mboxrd@z Thu Jan 1 00:00:00 1970 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=-5.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 F229EC11D00 for ; Thu, 20 Feb 2020 07:47:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C32F5208C4 for ; Thu, 20 Feb 2020 07:47:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="OPTgFSrZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726756AbgBTHrz (ORCPT ); Thu, 20 Feb 2020 02:47:55 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:60522 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726248AbgBTHrz (ORCPT ); Thu, 20 Feb 2020 02:47:55 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: Content-Type:In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:To: Subject:Sender:Reply-To:Content-ID:Content-Description; bh=E3T563SF0eKEHoviTTxB3y6ZGmgRDG+L2KrkBZJ8dno=; b=OPTgFSrZoBEjxRwh4HmFXrbEoV qiDx0U0lhfLIESR79Dln5kgHaSrj5vRKjhFLFrWJrnaNugG9qcUrIR1HrBE9g2HGeCgtgpAGqySCu VqZxd2fNzdW58mJKtE9cbWEl3yHmIcyNQT7naYMMkmO6WwXH3OirVwFCWffMMAYPwfL5wm7fX/1bD 2wXCR1yCB3qOi6eXBz5Jp40xczg0uVGUmEK5vYLU274nMZargLsDjIk0OuPY8i4Cqc/p0ttafsFhT G5uIL8INi2oW/n3NMTTso7pklEoCd/9sQdyxlTyMf2WN8KsFS8v1buFz3HpJERKdtdeTi0LUagvWn sM4FYqIQ==; Received: from [2601:1c0:6280:3f0::19c2] by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1j4gYs-0002eN-Or; Thu, 20 Feb 2020 07:47:54 +0000 Subject: Re: [RFC PATCH v3 3/8] drivers: base: add linear ranges helpers To: Matti Vaittinen , mazziesaccount@gmail.com Cc: Sebastian Reichel , Rob Herring , Mark Rutland , Greg Kroah-Hartman , "Rafael J. Wysocki" , Liam Girdwood , Mark Brown , linux-pm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Markus Laine , Mikko Mutanen References: <1f6cb9fb9dbc429dc48110f18ad3a8c0c40196c6.1582182989.git.matti.vaittinen@fi.rohmeurope.com> From: Randy Dunlap Message-ID: <2f0755df-4bc6-c53d-edea-45bc99e6a47b@infradead.org> Date: Wed, 19 Feb 2020 23:47:52 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <1f6cb9fb9dbc429dc48110f18ad3a8c0c40196c6.1582182989.git.matti.vaittinen@fi.rohmeurope.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi, Here are some kernel-doc comments for you: On 2/19/20 11:35 PM, Matti Vaittinen wrote: > --- > drivers/base/Kconfig | 3 + > drivers/base/Makefile | 1 + > drivers/base/linear_ranges.c | 246 +++++++++++++++++++++++++++++++++++ > include/linux/linear_range.h | 48 +++++++ > 4 files changed, 298 insertions(+) > create mode 100644 drivers/base/linear_ranges.c > create mode 100644 include/linux/linear_range.h > diff --git a/drivers/base/linear_ranges.c b/drivers/base/linear_ranges.c > new file mode 100644 > index 000000000000..5fa3b96bf2b8 > --- /dev/null > +++ b/drivers/base/linear_ranges.c > @@ -0,0 +1,246 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * linear_ranges.c -- helpers to map values in a linear range to range index > + * > + * Original idea borrowed from regulator framework > + * > + * It might be useful if we could support also inversely proportional ranges? > + * Copyright 2020 ROHM Semiconductors > + */ > + > +#include > +#include > +#include > +#include > + > +/** > + * linear_range_values_in_range - return the amount of values in a range > + * > + * @r: pointer to linear range where values are counted > + * > + * Compute the amount of values in range pointed by @r. Note, values can > + * be all equal - range with selectors 0,...,2 with step 0 still contains > + * 3 values even though they are all equal. > + * > + * Returns the amount of values in range pointed by @r * Return: ... > + */ > + > +/** > + * linear_range_values_in_range_array - return the amount of values in ranges > + * > + * @r: pointer to array of linear ranges where values are counted > + * @ranges: amount of ranges we include in computation. > + * > + * Compute the amount of values in ranges pointed by @r. Note, values can > + * be all equal - range with selectors 0,...,2 with step 0 still contains > + * 3 values even though they are all equal. > + * > + * Returns the amount of values in first @ranges ranges pointed by @r * Return: ... > + */ > + > +/** > + * linear_range_get_max_value - return the largest value in a range > + * > + * @r: pointer to linear range where value is looked from > + * > + * Returns the largest value in the given range ditto. > + */ > + > +/** > + * linear_range_get_value - fetch a value from given range > + * > + * @r: pointer to linear range where value is looked from > + * @selector: selector for which the value is searched > + * @val: address where found value is updated > + * > + * Search given ranges for value which matches given selector. > + * > + * Returns 0 on success, -EINVAL given selector is not found from any of the ditto. > + * ranges. > + */ > + > +/** > + * linear_range_get_value_array - fetch a value from array of ranges > + * > + * @r: pointer to array of linear ranges where value is looked from > + * @ranges: amount of ranges in an array > + * @selector: selector for which the value is searched > + * @val: address where found value is updated > + * > + * Search through an array of ranges for value which matches given selector. > + * > + * Returns 0 on success, -EINVAL given selector is not found from any of the same, again. > + * ranges. > + */ > + > +/** > + * linear_range_get_selector_low - return linear range selector for value > + * > + * @r: pointer to linear range where selector is looked from > + * @val: value for which the selcetor is searched selector > + * @selector: address where found selector value is updated > + * @found: flag to indicate that given value was in the range > + * > + * Return selector which which range value is closest match for given * Return: > + * input value. Value is matching if it is equal or smaller than given > + * value. If given value is in the range, then @found is set true. > + * > + * Returns 0 on success, -EINVAL if range is invalid or does not contain > + * value smaller or equal to given value > + */ > +int linear_range_get_selector_low(const struct linear_range *r, > + unsigned int val, unsigned int *selector, > + bool *found) > +{ > + *found = false; > + > + if (r->min > val) > + return -EINVAL; > + > + if (linear_range_get_max_value(r) >= val) > + *found = true; > + > + if (!r->step) > + *selector = r->min_sel; > + else > + *selector = (val - r->min) / r->step + r->min_sel; > + > + return 0; > +} > +EXPORT_SYMBOL(linear_range_get_selector_low); > + > +/** > + * linear_range_get_selector_low_array - return linear range selector for value > + * > + * @r: pointer to array of linear ranges where selector is looked from > + * @ranges: amount of ranges to scan from array > + * @val: value for which the selcetor is searched selector > + * @selector: address where found selector value is updated > + * @found: flag to indicate that given value was in the range > + * > + * Return Scan array of ranges for selector which which range value matches drop "Return" ? > + * given input value. Value is matching if it is equal or smaller than given > + * value. If given value is found to be in a range scannins is stopped and scanning > + * @found is set true. If a range with values smaller than given value is found > + * but the range max is being smaller than given value, then the ranges > + * biggest selector is updated to @selector but scanning ranges is continued > + * and @found is set to false. > + * > + * Returns 0 on success, -EINVAL if range array is invalid or does not contain * Return: > + * range with a value smaller or equal to given value > + */ > + > +/** > + * linear_range_get_selector_high - return linear range selector for value > + * > + * @r: pointer to linear range where selector is looked from > + * @val: value for which the selcetor is searched selector > + * @selector: address where found selector value is updated > + * @found: flag to indicate that given value was in the range > + * > + * Return selector which which range value is closest match for given > + * input value. Value is matching if it is equal or higher than given > + * value. If given value is in the range, then @found is set true. > + * > + * Returns 0 on success, -EINVAL if range is invalid or does not contain * Return: > + * value greater or equal to given value > + */ cheers. -- ~Randy