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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 97A83C43441 for ; Tue, 13 Nov 2018 12:47:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 62A7222419 for ; Tue, 13 Nov 2018 12:47:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 62A7222419 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=glider.be Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733061AbeKMWps (ORCPT ); Tue, 13 Nov 2018 17:45:48 -0500 Received: from laurent.telenet-ops.be ([195.130.137.89]:48296 "EHLO laurent.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732884AbeKMWps (ORCPT ); Tue, 13 Nov 2018 17:45:48 -0500 Received: from ramsan.of.borg ([84.194.111.163]) by laurent.telenet-ops.be with bizsmtp id zQnm1y0013XaVaC01QnmF2; Tue, 13 Nov 2018 13:47:46 +0100 Received: from rox.of.borg ([192.168.97.57]) by ramsan.of.borg with esmtp (Exim 4.86_2) (envelope-from ) id 1gMY6c-0005r9-0w; Tue, 13 Nov 2018 13:47:46 +0100 Received: from geert by rox.of.borg with local (Exim 4.90_1) (envelope-from ) id 1gMY6b-000222-VV; Tue, 13 Nov 2018 13:47:45 +0100 From: Geert Uytterhoeven To: Philipp Zabel Cc: Eric Auger , Alex Williamson , kvm@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH] reset: Add reset_control_get_count() Date: Tue, 13 Nov 2018 13:47:44 +0100 Message-Id: <20181113124744.7769-1-geert+renesas@glider.be> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently the reset core has internal support for counting the number of resets for a device described in DT. Generalize this to devices using lookup resets, and export it for public use. This will be used by generic drivers that need to be sure a device is controlled by a single, dedicated reset line (e.g. vfio-platform). Signed-off-by: Geert Uytterhoeven --- See https://lore.kernel.org/lkml/1539003437.11512.20.camel@pengutronix.de/ for the rationale to ensure a single, dedicated reset line. drivers/reset/core.c | 41 +++++++++++++++++++++++++++++++++++++++++ include/linux/reset.h | 7 +++++++ 2 files changed, 48 insertions(+) diff --git a/drivers/reset/core.c b/drivers/reset/core.c index 654e20ff2d5da9d4..c32b755ec373c338 100644 --- a/drivers/reset/core.c +++ b/drivers/reset/core.c @@ -859,3 +859,44 @@ devm_reset_control_array_get(struct device *dev, bool shared, bool optional) return rstc; } EXPORT_SYMBOL_GPL(devm_reset_control_array_get); + +static int reset_control_get_count_from_lookup(struct device *dev) +{ + const struct reset_control_lookup *lookup; + const char *dev_id = dev_name(dev); + int count = 0; + + if (!dev) + return -EINVAL; + + mutex_lock(&reset_lookup_mutex); + + list_for_each_entry(lookup, &reset_lookup_list, list) { + if (!strcmp(lookup->dev_id, dev_id)) + count++; + } + + mutex_unlock(&reset_lookup_mutex); + + if (count == 0) + count = -ENOENT; + + return count; +} + +/** + * of_reset_control_get_count - Count number of resets available with a device + * + * @dev: device for which to return the number of resets + * + * Returns positive reset count on success, or error number on failure and + * on count being zero. + */ +int reset_control_get_count(struct device *dev) +{ + if (dev->of_node) + return of_reset_control_get_count(dev->of_node); + + return reset_control_get_count_from_lookup(dev); +} +EXPORT_SYMBOL_GPL(reset_control_get_count); diff --git a/include/linux/reset.h b/include/linux/reset.h index f0b094130686bf32..2698b36bd1eb3e0c 100644 --- a/include/linux/reset.h +++ b/include/linux/reset.h @@ -32,6 +32,8 @@ struct reset_control *devm_reset_control_array_get(struct device *dev, struct reset_control *of_reset_control_array_get(struct device_node *np, bool shared, bool optional); +int reset_control_get_count(struct device *dev); + #else static inline int reset_control_reset(struct reset_control *rstc) @@ -97,6 +99,11 @@ of_reset_control_array_get(struct device_node *np, bool shared, bool optional) return optional ? NULL : ERR_PTR(-ENOTSUPP); } +static inline int reset_control_get_count(struct device *dev) +{ + return -ENOENT; +} + #endif /* CONFIG_RESET_CONTROLLER */ static inline int __must_check device_reset(struct device *dev) -- 2.17.1