From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A0BF3303A0D; Thu, 20 Aug 2026 22:54:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787266478; cv=none; b=vDOCdkDhABWo4tKagA7s6qcIJj8/sZhZZpdf5gJfpTmTAvzqMY3+A02k9Gcjd8D+9sIeyl1/TJ/wVRooZi9e+n44DKXiC8EZyzOtMPJab+21QH8FoBPZ8y/hU9B/xIjxc+oIBNwQN/z3drISarnyZGElK2JIFGtxG/IHTogTeVI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787266478; c=relaxed/simple; bh=9+MHsuZBuhFjLPoegaTal0e6+tfSDEXkir38gjIAXSA=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=QRjztZEDUVW1lFf662Dszn/AzmXPaifv7be/W/FqUGEIALPHI640vJKcysU8CHXjUJwW7DUnEbrFDUH8HPkTrqgUBzb5nve2slk08dNRIFCZB4btliW848xS6C1oDNu6F8ybXdcjae5lL1yuVqqYQwI8KEMHnfReJ6Lz0IQJUYw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ieL1gjkh; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ieL1gjkh" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 438AA1F000E9; Thu, 20 Aug 2026 22:54:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787266477; bh=8lC1I51w8t5S9/K8C61biVz8vw2mbhzdLExuupJ5UGA=; h=From:To:Cc:Subject:Date; b=ieL1gjkh3/FNzH2eOnU1dL39az86AIgkKUFA7gRmary2VpjuSZO0vzVd5crD5QZNO eDJey46BhySg4HfHg6AHypYefcQr1ORFnHsNEqZOgkr29jPn/bBPXn+OB4f9uQitEW tnsiXoQC0E5FnlryMgRcUgC51goob6HLeg4MyWHgTByVA3SDCzHFlsvWhmLh/UAlIB 3SH609yZmZxSe327CwQgWeUALFfkOIiJAwtWqjgyKUxKEk71hickRxLj3B5CaIbWwA Yw0G0SwxTa6rwXI0rZBWxtBbImtV04scieJrZfcNie2rNnorxyRAKubEstvBeyD8R+ ynCkrV9brcC/A== From: Danilo Krummrich To: krzk@kernel.org Cc: driver-core@lists.linux.dev, linux-kernel@vger.kernel.org, Danilo Krummrich Subject: [PATCH 1/3] w1: use match() callback instead of hardwiring dev->driver Date: Fri, 21 Aug 2026 00:54:09 +0200 Message-ID: <20260820225430.1847356-1-dakr@kernel.org> X-Mailer: git-send-email 2.55.0 Precedence: bulk X-Mailing-List: driver-core@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit w1 hardwires dev->driver before calling device_register(), relying on the if (dev->driver) special case in __device_attach() to call device_bind_driver() and skip normal matching. This is a legacy pattern that should be replaced with proper match() logic. Add device types for master and slave devices and implement a w1_match() callback that routes each device type to its corresponding driver. This lets the driver core bind w1 devices through the normal __device_attach_driver() path. Link: https://lore.kernel.org/driver-core/DKU2J83B6IX6.2CG1WOB66WC39@kernel.org/ Signed-off-by: Danilo Krummrich --- Compile-tested only, no hardware available. --- drivers/w1/w1.c | 37 +++++++++++++++++++++++++------------ 1 file changed, 25 insertions(+), 12 deletions(-) diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c index 486f321eadc8..faa1c03f4807 100644 --- a/drivers/w1/w1.c +++ b/drivers/w1/w1.c @@ -58,11 +58,6 @@ MODULE_PARM_DESC(slave_ttl, DEFINE_MUTEX(w1_mlock); LIST_HEAD(w1_masters); -static int w1_master_probe(struct device *dev) -{ - return -ENODEV; -} - static void w1_master_release(struct device *dev) { struct w1_master *md = dev_to_w1_master(dev); @@ -165,24 +160,42 @@ static struct w1_family w1_default_family = { .fops = &w1_default_fops, }; +static const struct device_type w1_master_device_type = { + .name = "w1_master", +}; + +static const struct device_type w1_slave_device_type = { + .name = "w1_slave", +}; + static int w1_uevent(const struct device *dev, struct kobj_uevent_env *env); +static struct device_driver w1_slave_driver; + +static int w1_match(struct device *dev, const struct device_driver *drv) +{ + if (dev->type == &w1_master_device_type) + return drv == &w1_master_driver; + if (dev->type == &w1_slave_device_type) + return drv == &w1_slave_driver; + return 0; +} static const struct bus_type w1_bus_type = { .name = "w1", + .match = w1_match, .uevent = w1_uevent, }; struct device_driver w1_master_driver = { .name = "w1_master_driver", .bus = &w1_bus_type, - .probe = w1_master_probe, }; struct device w1_master_device = { .parent = NULL, .bus = &w1_bus_type, + .type = &w1_master_device_type, .init_name = "w1 bus master", - .driver = &w1_master_driver, .release = &w1_master_release }; @@ -195,8 +208,8 @@ static struct device_driver w1_slave_driver = { struct device w1_slave_device = { .parent = NULL, .bus = &w1_bus_type, + .type = &w1_slave_device_type, .init_name = "w1 bus slave", - .driver = &w1_slave_driver, .release = &w1_slave_release }; #endif /* 0 */ @@ -574,11 +587,11 @@ static int w1_uevent(const struct device *dev, struct kobj_uevent_env *env) const char *event_owner, *name; int err = 0; - if (dev->driver == &w1_master_driver) { + if (dev->type == &w1_master_device_type) { md = container_of(dev, struct w1_master, dev); event_owner = "master"; name = md->name; - } else if (dev->driver == &w1_slave_driver) { + } else if (dev->type == &w1_slave_device_type) { sl = container_of(dev, struct w1_slave, dev); event_owner = "slave"; name = sl->name; @@ -590,7 +603,7 @@ static int w1_uevent(const struct device *dev, struct kobj_uevent_env *env) dev_dbg(dev, "Hotplug event for %s %s, bus_id=%s.\n", event_owner, name, dev_name(dev)); - if (dev->driver != &w1_slave_driver || !sl) + if (dev->type != &w1_slave_device_type || !sl) goto end; err = add_uevent_var(env, "W1_FID=%02X", sl->reg_num.family); @@ -666,8 +679,8 @@ static int __w1_attach_slave_device(struct w1_slave *sl) int err; sl->dev.parent = &sl->master->dev; - sl->dev.driver = &w1_slave_driver; sl->dev.bus = &w1_bus_type; + sl->dev.type = &w1_slave_device_type; sl->dev.release = &w1_slave_release; sl->dev.groups = w1_slave_groups; sl->dev.of_node = of_find_matching_node(sl->master->dev.of_node, base-commit: 073e62fd33fe9cec754cb89e60c0ebbab781a50a -- 2.55.0