From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f172.google.com (mail-pg1-f172.google.com [209.85.215.172]) (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 28BD83C0A02 for ; Sun, 2 Aug 2026 15:46:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785685597; cv=none; b=jpCXtHasF2jcmP28kRiwd+1u3VbnAU7Iav3cdymU6WY9bTleVGcl0QYG7NZyBt/JuQ5+42cIrNtn7hvPWJhR7xpNuAsLQp7qMRTSNJv6Em4vOx+qJuSiNA3CWuq6xNN5loqEbbuOoIfBlHeUqQlFXC/SUxbCD/qVZtX3M+z4xRk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785685597; c=relaxed/simple; bh=Mv2fB5QTMgzygfKi4oX9eQwPWNNkjLy2vCUnRHb4K0E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LaFg5QQ2OT16BsYsDADwtfDCe0VGU+MzcrUWdBfsuMjX+w0XCjyrOJ+aO9YFx5xsasr8yso4mmEsg/o4gTzkGo1E37qaWENeBOsDQB/x258RwFjw0UEXIM+XbOrfMgrj6INp9q0MLr0U+3tiCLBBgbs9jrLnwyEISChsSMF7Rf4= 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=qMFtgvkJ; arc=none smtp.client-ip=209.85.215.172 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="qMFtgvkJ" Received: by mail-pg1-f172.google.com with SMTP id 41be03b00d2f7-ca7c1176317so2273769a12.1 for ; Sun, 02 Aug 2026 08:46:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1785685592; x=1786290392; 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=qMFtgvkJilu1Jb47IbDRWK0rgi8TfMB5dhX6YvSrkBWuPak0x9hqM1OXUoYHH4UsXq PWsKri8MRpuqN82Zifecsb4yB5xkRHZvS4dQLxWA9or7mtRec92uPOYU2IiAcf+K4lUR y7Cq8/W8dlzViTzq2o5GmjYvkg8GGbpF51J46oVLpfIOOgG1zZIQc9AhYs5lqzbIhZcd OIrEXtp4MMnfbl7fONSFA04QQ4epgrwWzD1FKLAtYkpCp6+zB6Tu8kLVQpJ8ESlBX5r1 5T++mjmoN5NNJn6dPlyhAoEaHoHN1Wv/g+3vzJiI+Pn/vRlWDbRQMRtYJHlRCezLX3qk QwIA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785685592; x=1786290392; 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=nrP9S/rkPDcjkHsptt1/pnqiaJXJk/SZ6Gl0FNFQvgpAOTiUHSM0YwRT9EuUCP8v2M Xd6z0al2CF50iCQGdbfFlG4X8LrGaVPeTG6y2NmEl5qA5L+EA+t6/ZPdZffgUGPqrHc6 ewjsB1+MCEIjpCttzxfUSb7q/c71P8QEvIOcoOi86iS6imJvhF5L13C4UI39R6YUeKvj sAONnERXsOP2NqobGMBSaj3SgJN3g7+r1CoIAnuPwKKWb4O3GItKifn+CVkQtQxvX3NW 6NFV4ZzsNJJ9eJxNVe1cS3LoR0P6Nfth5+pCVhBN3Jng8JxMcip6EfQuTAyK3XcwI7gt WhcQ== X-Forwarded-Encrypted: i=1; AHgh+Rp2+qgPVKaMnNsofzo9cr9xXZ096e5bJwcXh/Z+V57D0QYtLi+ip2szEzXogFdyu4plKbnpVDEU0hXYGjM=@vger.kernel.org X-Gm-Message-State: AOJu0Yw09c+sjpNsAmDrlInLtc3Z9Hni77YU6WGxXQWEu+duk/9i7Uz1 fyagfWAiXfMcfT3IO3xL6w4fysQBO0YyUl5Xk09vof+3S6lnv6tEZ6f1 X-Gm-Gg: AR+sD10FUiw2rYFcrEIM4sY9oyb+or1sPhCuQ9KIOjWtsWSaIp6U2tvvijtsnm3m4dW 63bz8qTUvu1vLSroBh/sHR92qh7KA/NpgHOGONxea1p/Nx65U2xWoKvuXi6/qqcKFIS2mmIZS2j +nT8AQFIn6ll68oEKecGiz/qJV9X8EYpVCk0J3kePZG0m/bD3D0ossemDUKavnnkXuDWuN5Ew2W ftANPQyQKYwPUX+LX97Bs4BKnpacvG7mv/PnrXPT18n/qTGDzqVjUQFmLkndDmudcHEI6IP6Kgx LYYw4Va97k4vYMThYI3AkHmg1DeHZucvqtX/TjYDT8FTfo9gexHQlZpyA3Syt9JOXaGzUNZnGrg YyJAG0ZlGXPvly8T0ibn+SZnB3gsGClVt2/PT9Gx+Ba2uZ1//QA0w6/kmOuKseAyaO3/In6rkM5 K1x5MBx0a7QQuUKdK+lcolVrAn/t6sgSn/gO1qvAIhuzc/55K2TOkGvG5C2ReD1/PJhWtV+r2EN 0TtWivQEWqEQ71X7xePUM0usUARMcxUOdFdm/I= X-Received: by 2002:a05:6a21:7a95:b0:3c1:85d:fa2f with SMTP id adf61e73a8af0-3c92a89c7bbmr7671642637.36.1785685592428; Sun, 02 Aug 2026 08:46:32 -0700 (PDT) Received: from Mac.net (198-27-228-154.fiber.dynamic.sonic.net. [198.27.228.154]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-3153e29a126sm30602192eec.31.2026.08.02.08.46.30 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Sun, 02 Aug 2026 08:46:31 -0700 (PDT) From: Ahmad Byagowi To: Lee Jones , Pavel Machek , Richard Cochran , Vadim Fedorenko , Andi Shyti , Peter Rosin Cc: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Andrew Lunn , davem@davemloft.net, Eric Dumazet , Jakub Kicinski , Paolo Abeni , linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-i2c@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Ahmad Byagowi Subject: [RFC net-next 3/4] i2c: mux: Propagate software nodes to channel adapters Date: Sun, 2 Aug 2026 08:46:19 -0700 Message-ID: <3e76f1dc25b104a2c8558142c12e23b297f9c58c.1785684064.git.ahmadexp@gmail.com> X-Mailer: git-send-email 2.50.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@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)