From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f42.google.com (mail-pj1-f42.google.com [209.85.216.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 79C8E4334A2 for ; Mon, 3 Aug 2026 20:50:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.42 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785790231; cv=none; b=UiS8mcZipqAkAgtkP130LAP274DkBYeo3dtedv/+KIO1a3J6dwppQVAxp0AcEl0VcUai+OaIo5Zwz/12PqQ4tfJB5AAeYlNDusp4JvX4Kwspf5p1MvBxU2VpSWpmO9AGRECsHA2t06YlucySvrNvRB64slDNwiQSYmnPdMyB9Zw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785790231; c=relaxed/simple; bh=Mv2fB5QTMgzygfKi4oX9eQwPWNNkjLy2vCUnRHb4K0E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jDZd1in1tb2ERrqQTdLeoXk0GHUebZ75ev6vnPVWjBfsqjx3vGLcQehxyCvRDxCz531yAm7yWi0uyEecNEPY/bihH/a4ZoeVWHyZe47F1dPU5GC7NS9Cz+HevREgM4coiXi1DEEUtpjI9uxqhnsy/u1O1WhyOCKaKho46sq63XI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=R5/NJ34K; arc=none smtp.client-ip=209.85.216.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="R5/NJ34K" Received: by mail-pj1-f42.google.com with SMTP id 98e67ed59e1d1-38e071ed6aeso2899498a91.0 for ; Mon, 03 Aug 2026 13:50:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1785790230; x=1786395030; darn=vger.kernel.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:content-type; bh=jXjf3n6y2o2sUp9ziyNWD3SU5x1Q1/QeHjG5pG2QUDY=; b=R5/NJ34KbgbSSSwP/mL7/dZ/mxx+64Oj39jF8LRMthrCM21JJAEe9emil60hag8QPu nVAiKqVQ5JkM893S+WpcxRS8TZpKxim9FquWzc9SyaIB8Ijh3lXCr4+vDyq5CerCcgrw LZg75+PfFwImIuT/JAOZMFSdKyMb1rhviawBF7V73lMvl2JUbcNchdVxqde8bhe1tbj5 rrxbhvvh1dTpyHdVhQoC6rY6jHOmNsDuR14gQXJqsZVfEK4Oly3LWWQz68rIgapkToDf vfDnp5I4EsbeeViocd1l3xMKGjNGzs4YBBUPH/xeeWOd6tLHBhih0ZjLxtZaiDDd+FLk C2+w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785790230; x=1786395030; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=jXjf3n6y2o2sUp9ziyNWD3SU5x1Q1/QeHjG5pG2QUDY=; b=HkQFzErPEkETA3aMRo7q5/tYoGsPxhPD7XC731sD3g/L5/RoXk/b5m/p3BwLeieKp4 0wlL1R6LzOQfzABxpJymUIEX/8TKQ5C1cvp8ob1N/DUi5vRWIe+S2JpTD6CuK0Wyxe9F QkoPnk/M/h4zHl7jmY4bW/UqjRSIBCOCUTLaogufctl3i0Y3O7J8TQdA8LthRvV0TPuJ V7hogw3tL2LiUY3KXZQl+dpZZYP/JVFuY+SkNCyFN+RRd9dcqDd3Rr7dyDoHBDxhfHFK FVfSmBvUZY7P5WlKQ3b3Rx1D7WkucBlZMTFFRKi3hgcW4Q3qySbV5HK93EJABEShpQFU Qa4g== X-Forwarded-Encrypted: i=1; AHgh+Rr59yjP1oo+0p1btcsOMKx6TvepXZxmgLVosq80gMI749dzGkIHEcfEwGt20/Zh7Ba2TisfsT9X1E8=@vger.kernel.org X-Gm-Message-State: AOJu0Yx4/qvtsfDNmDr+Zm/6zC0TsvhQGc8blK8QzKbYBEVjaAK/Aq21 7WPi8S9Dzq3cO1JjGHkseNbH0RDeynb8QStH5EX2tLMXvpll2JSTAiTR X-Gm-Gg: AR+sD123+JtHjf1wT0+bizRJYOWa9TZaSIkCAmAYcHNetXIYH888aluXAbINPl7715w d6cJFp4r7CCj0AYdtz11E1DkKgGqoYRWST3XvWf3n2WbWfHrNmhPlRSAwGuo0toSOdS0P3nn/qa N+5OlHG4Af2ugvp9zh+UMyK5mgs+IkoCTTdWjxKpjNrgfS1go6gP9ZmUvl4Viej+aSnF5b94u7C wfswJsljFhPJIwgARpCFXALpejNqRSM1wR9NVSD+EcE7BPCmdq0a/dPF7RjOwBhRztNhQgGMQgt rtlgg5OJZOibBMMu8hF5zxZogdKp0dr6tkv/XzvsFre5li2nAxsAjIOTKa5MfDmiMWmPRyx7mG9 2tfRpCGegFPCLhfDuFbsyZRvewq/OeNuhyz+B8idJh1dlQCZtV4o1Fywf+/3B3V2rH1dcj31AI1 I+cioWoFVDLEDlQelRZswRSRQVQk9CZZUiNF4AtSXDELT3CPiWzBm1tjoIWlmvu/v04rTix3l03 9cp9A== X-Received: by 2002:a17:90b:53c7:b0:38d:a150:ee04 with SMTP id 98e67ed59e1d1-38fbc4ef153mr9786906a91.30.1785790229767; Mon, 03 Aug 2026 13:50:29 -0700 (PDT) Received: from Mac.net ([12.162.234.74]) by smtp.gmail.com with ESMTPSA id a92af1059eb24-13fab4d10bbsm33112324c88.11.2026.08.03.13.50.26 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Mon, 03 Aug 2026 13:50:28 -0700 (PDT) From: Ahmad Byagowi To: linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-i2c@vger.kernel.org, netdev@vger.kernel.org Cc: Lee Jones , Pavel Machek , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Andi Shyti , Peter Rosin , Nam Tran , Vadim Fedorenko , Richard Cochran , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Kees Cook , "Gustavo A. R. Silva" , linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC net-next v2 3/6] i2c: mux: Propagate software nodes to channel adapters Date: Mon, 3 Aug 2026 13:50:08 -0700 Message-ID: <20260803205011.1249-4-ahmadexp@gmail.com> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20260803205011.1249-1-ahmadexp@gmail.com> References: <20260803205011.1249-1-ahmadexp@gmail.com> Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Device Tree channel nodes are associated with the adapters created by i2c-mux, but equivalent software-node descriptions are not. Find the software-node child whose reg value matches the channel and assign it to the new adapter. Keep a reference for the adapter lifetime so downstream clients can find the channel by firmware node. Signed-off-by: Ahmad Byagowi --- drivers/i2c/i2c-mux.c | 55 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c index 681a201c2..1e587ea4e 100644 --- a/drivers/i2c/i2c-mux.c +++ b/drivers/i2c/i2c-mux.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include @@ -264,6 +265,49 @@ static const struct i2c_lock_operations i2c_parent_lock_ops = { .unlock_bus = i2c_parent_unlock_bus, }; +static struct fwnode_handle * +i2c_mux_get_channel_swnode(struct i2c_mux_core *muxc, u32 chan_id) +{ + struct fwnode_handle *dev_node = dev_fwnode(muxc->dev); + struct fwnode_handle *mux_node, *child = NULL; + u32 reg; + + if (!is_software_node(dev_node)) + return NULL; + + if (muxc->arbitrator) + mux_node = fwnode_get_named_child_node(dev_node, "i2c-arb"); + else if (muxc->gate) + mux_node = fwnode_get_named_child_node(dev_node, "i2c-gate"); + else + mux_node = fwnode_get_named_child_node(dev_node, "i2c-mux"); + + if (mux_node) { + /* A "reg" property indicates an old-style firmware entry. */ + if (!fwnode_property_read_u32(mux_node, "reg", ®)) { + fwnode_handle_put(mux_node); + mux_node = NULL; + } + } + + if (!mux_node) + mux_node = fwnode_handle_get(dev_node); + else if (muxc->arbitrator || muxc->gate) + child = fwnode_handle_get(mux_node); + + if (!child) { + fwnode_for_each_child_node(mux_node, child) { + if (fwnode_property_read_u32(child, "reg", ®)) + continue; + if (chan_id == reg) + break; + } + } + + fwnode_handle_put(mux_node); + return child; +} + int i2c_mux_add_adapter(struct i2c_mux_core *muxc, u32 force_nr, u32 chan_id) { @@ -364,6 +408,12 @@ int i2c_mux_add_adapter(struct i2c_mux_core *muxc, priv->adap.dev.of_node = child; of_node_put(mux_node); + } else { + struct fwnode_handle *fwnode; + + fwnode = i2c_mux_get_channel_swnode(muxc, chan_id); + if (fwnode) + device_set_node(&priv->adap.dev, fwnode); } /* @@ -408,6 +458,8 @@ int i2c_mux_add_adapter(struct i2c_mux_core *muxc, return 0; err_free_priv: + if (is_software_node(dev_fwnode(&priv->adap.dev))) + fwnode_handle_put(dev_fwnode(&priv->adap.dev)); kfree(priv); return ret; } @@ -420,6 +472,7 @@ void i2c_mux_del_adapters(struct i2c_mux_core *muxc) while (muxc->num_adapters) { struct i2c_adapter *adap = muxc->adapter[--muxc->num_adapters]; struct i2c_mux_priv *priv = adap->algo_data; + struct fwnode_handle *fwnode = dev_fwnode(&adap->dev); struct device_node *np = adap->dev.of_node; muxc->adapter[muxc->num_adapters] = NULL; @@ -430,6 +483,8 @@ void i2c_mux_del_adapters(struct i2c_mux_core *muxc) sysfs_remove_link(&priv->adap.dev.kobj, "mux_device"); i2c_del_adapter(adap); + if (is_software_node(fwnode)) + fwnode_handle_put(fwnode); of_node_put(np); kfree(priv); } -- 2.50.1 (Apple Git-155)