From patchwork Thu Apr 11 23:56:22 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Saravana Kannan X-Patchwork-Id: 13626646 Received: from mail-pj1-f73.google.com (mail-pj1-f73.google.com [209.85.216.73]) (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 8E0F64F88A for ; Thu, 11 Apr 2024 23:56:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712879796; cv=none; b=gWrG2yQkPmLbb0WMZN2u+g89qOwPdGsuzgnJuyZmSRvap+ueIQpOdkQbonS1wdZkPM+1HJ0FFrN29OyQoDEcUJLFkL0Q+tK1qefABkQa7iZKeo00XC8NVuimjuI+sFT+pf2Ix0XvKEn0MWfUHkDDu4k6HvdnTMJ1Q2Lp61EJ4B0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712879796; c=relaxed/simple; bh=UD3bfhO0YU3iaHR4sW0PiOGB9kKHCclU23sLM4TNyko=; h=Date:In-Reply-To:Message-Id:Mime-Version:References:Subject:From: To:Cc:Content-Type; b=R/eRRm8pslZhCtBUzc6Zv6tMr8rv7Qq7D9/DKld0FeCzH0Rn2MEE24XK/r9qRr2Twq2fltKJeRSXCRt+LUsJdH+r3Yjairpe6MY1SDUoUngAteAyoZI4awhJxv44UcB6EPKV3rHB16930SyyARUdYgJ6uzpvHAmQ7FvIgGPlhcg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--saravanak.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=dnidCYdd; arc=none smtp.client-ip=209.85.216.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--saravanak.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="dnidCYdd" Received: by mail-pj1-f73.google.com with SMTP id 98e67ed59e1d1-2a2e6197371so310324a91.3 for ; Thu, 11 Apr 2024 16:56:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1712879794; x=1713484594; darn=vger.kernel.org; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=HizrqH7rz47v2QLp5elrgTIyG7EQRo9SAEpqH/+kBy0=; b=dnidCYddh4Hp9/Vk+RCG0BRni9c0LPOYrEwhKFJyNl7c/MkHmQJip5tAHce/H/Vcll 7gOfQ5VXal3ql81vb0cp0r+oJ4Z/MT5if8yfm4L9Q+spCXxYRvGpat49lkLVez4Qv2rt MdVhkQ46PUzxtNCYg8mHF32SepKfyudYxbPhK84zddM4CzU1ckGkH0OfwgmrysIf8YE3 sx7m2XO+lPECyrqGKJPfSn4SuMbCZzPeuXyr4R0u9PGoCyzPQzNzkmFRpLdvr6fZVF4N a+7pfCI7zOBT5D0MLV66V6FQVadHDmlriHdIf3OYW1XrZVkdoGIQA/M4X9AW8+iOJS7e /Fyg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1712879794; x=1713484594; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=HizrqH7rz47v2QLp5elrgTIyG7EQRo9SAEpqH/+kBy0=; b=PP2QS+IWTWwzIpUjjhQ7CLlep/kN/MJ1ofC+NtUIqHaE1h1veqtmWQ17q/Yusjsy+b S//T/p7tGa0O7vsmXesMOgrYXEavB0DZhPDIIpUBBKkY27YsKta8mIw62ugJQAzUc6Gk CNUh87WHtrn8ka5B10Cpp0rdmVenuq38HJzuwgTe5S1HQEbQ/cmWJwcDk8UONeHdZgBU wqlMeXxvl4pmBm/lFkLuS3QV+hvk/XwP6ASMGJ4h4iUp/1pj7zeRh2/QDGTFD3UdeUvw XFMGdpuE2uRUyVnL6nXFwNdcWeFMByIdS2dHPKmDPg7IIFKTjwz9zxKIOlK++ylsGkfd VuQQ== X-Forwarded-Encrypted: i=1; AJvYcCXPIMswvAf8ziYdh0NtFd7RKcsuPIxhQct6tfvJDEamE2UpQVVSCCsbb/eN7+LYSjZEY9bghZ7zcSPISkgczskhQDiXDSFyF4fApA== X-Gm-Message-State: AOJu0YyoU6FYEhkl+eJOX4+g0wv3INXSIdYA30RnBMHH60lqjmw05CWH 8lxZLY0iVsM+Ba7Vgvce0TwIvQ/oj9vRI4noBuTVbYW9bWn7UdTslAaoW6pChhcS93yXvW3Aq7B 7WE7yD5CyiX71og== X-Google-Smtp-Source: AGHT+IHqTq2UPkwQrTsIwISL3TPeqKf9uyBTI5tIlaviAP1Wf5pw15DCSNWSteziJ1gjlX/gPxjg3k35MoA1MA0= X-Received: from saravanak.san.corp.google.com ([2620:15c:2d:3:a472:f40c:d4ba:c29]) (user=saravanak job=sendgmr) by 2002:a17:90a:6546:b0:2a5:fb3a:32e6 with SMTP id f6-20020a17090a654600b002a5fb3a32e6mr3270pjs.4.1712879793807; Thu, 11 Apr 2024 16:56:33 -0700 (PDT) Date: Thu, 11 Apr 2024 16:56:22 -0700 In-Reply-To: <20240411235623.1260061-1-saravanak@google.com> Message-Id: <20240411235623.1260061-3-saravanak@google.com> Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240411235623.1260061-1-saravanak@google.com> X-Mailer: git-send-email 2.44.0.683.g7961c838ac-goog Subject: [PATCH v3 2/2] of: dynamic: Fix overlayed devices not probing because of fw_devlink From: Saravana Kannan To: Herve Codina , Greg Kroah-Hartman , "Rafael J. Wysocki" , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Wolfram Sang , Rob Herring , Saravana Kannan , Mark Brown , Len Brown , Andy Shevchenko , Daniel Scally , Heikki Krogerus , Sakari Ailus , Geert Uytterhoeven Cc: kernel-team@android.com, Wolfram Sang , linux-kernel@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-spi@vger.kernel.org, linux-acpi@vger.kernel.org When an overlay is applied, if the target device has already probed successfully and bound to a device, then some of the fw_devlink logic that ran when the device was probed needs to be rerun. This allows newly created dangling consumers of the overlayed device tree nodes to be moved to become consumers of the target device. Fixes: 1a50d9403fb9 ("treewide: Fix probing of devices in DT overlays") Reported-by: Herve Codina Closes: https://lore.kernel.org/lkml/CAMuHMdXEnSD4rRJ-o90x4OprUacN_rJgyo8x6=9F9rZ+-KzjOg@mail.gmail.com/ Closes: https://lore.kernel.org/all/20240221095137.616d2aaa@bootlin.com/ Closes: https://lore.kernel.org/lkml/20240312151835.29ef62a0@bootlin.com/ Signed-off-by: Saravana Kannan --- drivers/base/core.c | 76 +++++++++++++++++++++++++++++++++++++----- drivers/of/overlay.c | 15 +++++++++ include/linux/fwnode.h | 1 + 3 files changed, 83 insertions(+), 9 deletions(-) diff --git a/drivers/base/core.c b/drivers/base/core.c index 5f4e03336e68..1a646f393dd7 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -46,6 +46,8 @@ static bool fw_devlink_drv_reg_done; static bool fw_devlink_best_effort; static struct workqueue_struct *device_link_wq; +#define get_dev_from_fwnode(fwnode) get_device((fwnode)->dev) + /** * __fwnode_link_add - Create a link between two fwnode_handles. * @con: Consumer end of the link. @@ -237,6 +239,70 @@ static void __fw_devlink_pickup_dangling_consumers(struct fwnode_handle *fwnode, __fw_devlink_pickup_dangling_consumers(child, new_sup); } +static void fw_devlink_pickup_dangling_consumers(struct device *dev) +{ + struct fwnode_handle *child; + + mutex_lock(&fwnode_link_lock); + fwnode_for_each_available_child_node(dev->fwnode, child) + __fw_devlink_pickup_dangling_consumers(child, dev->fwnode); + __fw_devlink_link_to_consumers(dev); + mutex_unlock(&fwnode_link_lock); +} + +/** + * fw_devlink_refresh_fwnode - Recheck the tree under this firmware node + * @fwnode: The fwnode under which the fwnode tree has changed + * + * This function is mainly meant to adjust the supplier/consumer dependencies + * after a fwnode tree overlay has occurred. + */ +void fw_devlink_refresh_fwnode(struct fwnode_handle *fwnode) +{ + struct device *dev; + + /* + * Find the closest ancestor fwnode that has been converted to a device + * that can bind to a driver (bus device). + */ + fwnode_handle_get(fwnode); + do { + if (fwnode->flags & FWNODE_FLAG_NOT_DEVICE) + continue; + + dev = get_dev_from_fwnode(fwnode); + if (!dev) + continue; + + if (dev->bus) + break; + + put_device(dev); + } while ((fwnode = fwnode_get_next_parent(fwnode))); + + /* + * If none of the ancestor fwnodes have (yet) been converted to a device + * that can bind to a driver, there's nothing to fix up. + */ + if (!fwnode) + return; + + WARN(device_is_bound(dev) && dev->links.status != DL_DEV_DRIVER_BOUND, + "Don't multithread overlaying and probing the same device!\n"); + + /* + * If the device has already bound to a driver, then we need to redo + * some of the work that was done after the device was bound to a + * driver. If the device hasn't bound to a driver, running thing too + * soon would incorrectly pick up consumers that it shouldn't. + */ + if (dev->links.status == DL_DEV_DRIVER_BOUND) + fw_devlink_pickup_dangling_consumers(dev); + + put_device(dev); + fwnode_handle_put(fwnode); +} + static DEFINE_MUTEX(device_links_lock); DEFINE_STATIC_SRCU(device_links_srcu); @@ -1322,14 +1388,8 @@ void device_links_driver_bound(struct device *dev) * child firmware node. */ if (dev->fwnode && dev->fwnode->dev == dev) { - struct fwnode_handle *child; fwnode_links_purge_suppliers(dev->fwnode); - mutex_lock(&fwnode_link_lock); - fwnode_for_each_available_child_node(dev->fwnode, child) - __fw_devlink_pickup_dangling_consumers(child, - dev->fwnode); - __fw_devlink_link_to_consumers(dev); - mutex_unlock(&fwnode_link_lock); + fw_devlink_pickup_dangling_consumers(dev); } device_remove_file(dev, &dev_attr_waiting_for_supplier); @@ -1888,8 +1948,6 @@ static void fw_devlink_unblock_consumers(struct device *dev) device_links_write_unlock(); } -#define get_dev_from_fwnode(fwnode) get_device((fwnode)->dev) - static bool fwnode_init_without_drv(struct fwnode_handle *fwnode) { struct device *dev; diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c index 2ae7e9d24a64..7b2396c53127 100644 --- a/drivers/of/overlay.c +++ b/drivers/of/overlay.c @@ -179,6 +179,15 @@ static int overlay_notify(struct overlay_changeset *ovcs, return 0; } +static void overlay_fw_devlink_refresh(struct overlay_changeset *ovcs) +{ + for (int i = 0; i < ovcs->count; i++) { + struct device_node *np = ovcs->fragments[i].target; + + fw_devlink_refresh_fwnode(of_fwnode_handle(np)); + } +} + /* * The values of properties in the "/__symbols__" node are paths in * the ovcs->overlay_root. When duplicating the properties, the paths @@ -953,6 +962,12 @@ static int of_overlay_apply(struct overlay_changeset *ovcs, pr_err("overlay apply changeset entry notify error %d\n", ret); /* notify failure is not fatal, continue */ + /* + * Needs to happen after changset notify to give the listeners a chance + * to finish creating all the devices they need to create. + */ + overlay_fw_devlink_refresh(ovcs); + ret_tmp = overlay_notify(ovcs, OF_OVERLAY_POST_APPLY); if (ret_tmp) if (!ret) diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h index 0d79070c5a70..95a78b87777a 100644 --- a/include/linux/fwnode.h +++ b/include/linux/fwnode.h @@ -220,6 +220,7 @@ int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup, u8 flags); void fwnode_links_purge(struct fwnode_handle *fwnode); void fw_devlink_purge_absent_suppliers(struct fwnode_handle *fwnode); +void fw_devlink_refresh_fwnode(struct fwnode_handle *fwnode); bool fw_devlink_is_strict(void); #endif