From patchwork Wed Oct 30 07:22:23 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen-Yu Tsai X-Patchwork-Id: 13856066 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 8CC50D7497D for ; Wed, 30 Oct 2024 07:26:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=02I89/A9qYtjldvjbyC2sOJfVnDSFABqZCnk6WuuKr0=; b=Y1d9jGVpEBohgxzv2ZhH8nwomK PdTjWgNRaGgyhJzjlC9Q/G62y4RqV8R5DSw3+LBZsN6HdWvRU4sdI+QY+eaeeSZBCrsy2gC//4Upt NEN5kNDoC8QM+jKmqcFjwpp5jsBg7f/ENw2tmoXzZmoMFDYUfKxZ7b9tWyoLus6PAgtxAe6eQja5/ iQSfgmZCkzi7ZQ6Tl4uWqG3X+SyhE10moMn3ssS137O/CsiBx8/fUgOlJdwpwPImvyAh9Au9Xdvey 3QtAw+tBoQsDBb2qd5pGN8wdDUnLlvfkeC7gK6OXDRHZoXpoUqwRsBVxBGczwJFVuWzdImE0VL2YC fW4UGEnA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1t635g-0000000H8X5-2ihq; Wed, 30 Oct 2024 07:26:04 +0000 Received: from mail-pl1-x62e.google.com ([2607:f8b0:4864:20::62e]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1t632R-0000000H7kv-0mqw for linux-mediatek@lists.infradead.org; Wed, 30 Oct 2024 07:22:44 +0000 Received: by mail-pl1-x62e.google.com with SMTP id d9443c01a7336-20c77459558so53652755ad.0 for ; Wed, 30 Oct 2024 00:22:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1730272963; x=1730877763; darn=lists.infradead.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=02I89/A9qYtjldvjbyC2sOJfVnDSFABqZCnk6WuuKr0=; b=ZW98pLYDYAXf6rKDPbZyenTWD0PnCQaHN8x20XNq3nuEkHsWKGPrNvZ/XicSqb6cg8 RS/bklBugfqgFWqVgTG6CCLym2opOVlvCEV0Zh38OTqU4jGEVW77/k/ZWzc+o4rjPqnA eVaAA9GDiDDVNUx0fxbZQcY5jhHUya7n+nSs0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1730272963; x=1730877763; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=02I89/A9qYtjldvjbyC2sOJfVnDSFABqZCnk6WuuKr0=; b=v85KJOBBstKyRKLjWBqlo/ZniGXrtz9iQwwAej5982yHY+Dxf0g1UgWJ03D1c7R+65 hEBAWu4vDAi0IocB6MrAfV52ZbpePprANYMUtMwCE4lQLs9KFkkNmf14JB0SnHPXaPs7 sg8Tyw/zd96/DIn4xwrof6ZgXLPEQVF7NLr9eongxuuTNZ68181RsVGxNysZRea8CByd 3OekFHU/t+Dv0HCYbh88uv9rOrIxnu4zaLh2UZ2fH9N+16/6f02Hse4Rp5Uk44RWn/vp 4It0BFG717/4TUTWOkfIO5IkyteRiBk7wdRPd5iJN+T3MsvILVxUsXyF2woOSVPJjiTH 3CIA== X-Forwarded-Encrypted: i=1; AJvYcCUR9x5GkHBK0XfzvJDf7d8Qhxg+QnjnudqEjz99lufTs2eVXobBd+pNzXFgfQvyPU4yNzUsJDll5R3dLBVsIQ==@lists.infradead.org X-Gm-Message-State: AOJu0YzEgxVS/7L6R/y8mqNWKA+oms/j7WIvj7zz/8TRyL+RkUeCxfjy f17AwAlFuUMTsR0qdKtmgxoOA6348v80sN8yODMfeU24Oe1oTvsc/ksJTzYqxA== X-Google-Smtp-Source: AGHT+IGRv+883MbPDyi2+STjJPcbXoBWTOIxB4iDvZKH1B5wRpkiQ+ZAYsXKMtOIPXpNfDDwdLlFAg== X-Received: by 2002:a17:903:41c4:b0:20f:ab2e:14f9 with SMTP id d9443c01a7336-210f76ff17amr26213175ad.55.1730272962610; Wed, 30 Oct 2024 00:22:42 -0700 (PDT) Received: from wenstp920.tpe.corp.google.com ([2401:fa00:1:10:d1f3:aa64:657f:d8a8]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-210bc02e67esm76641445ad.186.2024.10.30.00.22.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 30 Oct 2024 00:22:42 -0700 (PDT) From: Chen-Yu Tsai To: Rob Herring , Saravana Kannan , Matthias Brugger , AngeloGioacchino Del Regno , Wolfram Sang Cc: Chen-Yu Tsai , Benson Leung , Tzung-Bi Shih , chrome-platform@lists.linux.dev, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, Douglas Anderson , Johan Hovold , Jiri Kosina , Andy Shevchenko , linux-i2c@vger.kernel.org Subject: [PATCH v10 2/7] of: base: Add for_each_child_of_node_with_prefix() Date: Wed, 30 Oct 2024 15:22:23 +0800 Message-ID: <20241030072229.1013235-3-wenst@chromium.org> X-Mailer: git-send-email 2.47.0.163.g1226f6d8fa-goog In-Reply-To: <20241030072229.1013235-1-wenst@chromium.org> References: <20241030072229.1013235-1-wenst@chromium.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241030_002243_257751_A9AE2B01 X-CRM114-Status: GOOD ( 14.95 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org There are cases where drivers would go through child device nodes and operate on only the ones whose node name starts with a given prefix. Provide a helper for these users. This will mainly be used in a subsequent patch that implements a hardware component prober for I2C busses. Signed-off-by: Chen-Yu Tsai Reviewed-by: Rob Herring (Arm) --- Changes since v7: - Collected Rob's Reviewed-by Changes since v6: - Changed helper name to "for_each_child_of_node_with_prefix()" Changes since v5: - New patch --- drivers/of/base.c | 35 +++++++++++++++++++++++++++++++++++ include/linux/of.h | 9 +++++++++ 2 files changed, 44 insertions(+) diff --git a/drivers/of/base.c b/drivers/of/base.c index d94efee4a7fc..a01e5534c2fd 100644 --- a/drivers/of/base.c +++ b/drivers/of/base.c @@ -628,6 +628,41 @@ struct device_node *of_get_next_child(const struct device_node *node, } EXPORT_SYMBOL(of_get_next_child); +/** + * of_get_next_child_with_prefix - Find the next child node with prefix + * @node: parent node + * @prev: previous child of the parent node, or NULL to get first + * + * This function is like of_get_next_child(), except that it automatically + * skips any nodes whose name doesn't have the given prefix. + * + * Return: A node pointer with refcount incremented, use + * of_node_put() on it when done. + */ +struct device_node *of_get_next_child_with_prefix(const struct device_node *node, + struct device_node *prev, + const char *prefix) +{ + struct device_node *next; + unsigned long flags; + + if (!node) + return NULL; + + raw_spin_lock_irqsave(&devtree_lock, flags); + next = prev ? prev->sibling : node->child; + for (; next; next = next->sibling) { + if (!of_node_name_prefix(next, prefix)) + continue; + if (of_node_get(next)) + break; + } + of_node_put(prev); + raw_spin_unlock_irqrestore(&devtree_lock, flags); + return next; +} +EXPORT_SYMBOL(of_get_next_child_with_prefix); + static struct device_node *of_get_next_status_child(const struct device_node *node, struct device_node *prev, bool (*checker)(const struct device_node *)) diff --git a/include/linux/of.h b/include/linux/of.h index d0307e3b093d..f921786cb8ac 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -289,6 +289,9 @@ extern struct device_node *of_get_parent(const struct device_node *node); extern struct device_node *of_get_next_parent(struct device_node *node); extern struct device_node *of_get_next_child(const struct device_node *node, struct device_node *prev); +extern struct device_node *of_get_next_child_with_prefix(const struct device_node *node, + struct device_node *prev, + const char *prefix); extern struct device_node *of_get_next_available_child( const struct device_node *node, struct device_node *prev); extern struct device_node *of_get_next_reserved_child( @@ -1468,6 +1471,12 @@ static inline int of_property_read_s32(const struct device_node *np, child != NULL; \ child = of_get_next_child(parent, child)) +#define for_each_child_of_node_with_prefix(parent, child, prefix) \ + for (struct device_node *child __free(device_node) = \ + of_get_next_child_with_prefix(parent, NULL, prefix); \ + child != NULL; \ + child = of_get_next_child_with_prefix(parent, child, prefix)) + #define for_each_available_child_of_node(parent, child) \ for (child = of_get_next_available_child(parent, NULL); child != NULL; \ child = of_get_next_available_child(parent, child))