From nobody Sat Apr 4 00:24:37 2026 Received: from inva021.nxp.com (inva021.nxp.com [92.121.34.21]) (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 3439C2D97BD; Mon, 23 Mar 2026 06:27:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=92.121.34.21 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774247280; cv=none; b=RZzkX1knQO5euRZ4bkdaIphVcHJcS5dbEav7Fa+timQ3teUSk/Lc83GmOSscEbm4kC0N04Qo3zDjtuRRK2CmXjiUHFXNTIMW1xypbclVSlAsIr/yIP23Sfe7omsDZT4EJv7qQHWVbmL00Y6cMx6mGQbh7AuQYibvsRoXObCaonw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774247280; c=relaxed/simple; bh=1W7BaifyytoxpOgRpD4mD1PQB1euBZURGl/DDeth9Vg=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Vk/ZvefyOXNLKY+munkEpTffCdjnEVUkZJkqdnFZaQdxufwnsdbCjqJH05aztS+CQeq08HQiRClXk5Iyjr7YHAbWI8wOjuzs2JcLVmNGBpgYJXH9OKBBXIGTiPaJVCeXCKduNku/hmA8/x2ceryCLJFAgYYkF8vkLSJyvYAsTCI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=nxp.com; spf=pass smtp.mailfrom=nxp.com; arc=none smtp.client-ip=92.121.34.21 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=nxp.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=nxp.com Received: from inva021.nxp.com (localhost [127.0.0.1]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id 027C2200A5E; Mon, 23 Mar 2026 07:27:47 +0100 (CET) Received: from aprdc01srsp001v.ap-rdc01.nxp.com (aprdc01srsp001v.ap-rdc01.nxp.com [165.114.16.16]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id BE949200A5A; Mon, 23 Mar 2026 07:27:46 +0100 (CET) Received: from lsv03900.swis.in-blr01.nxp.com (lsv03900.swis.in-blr01.nxp.com [10.12.177.15]) by aprdc01srsp001v.ap-rdc01.nxp.com (Postfix) with ESMTP id 79E561800083; Mon, 23 Mar 2026 14:27:45 +0800 (+08) From: Lakshay Piplani To: linux-kernel@vger.kernel.org, linux-i3c@lists.infradead.org, alexandre.belloni@bootlin.com, krzk+dt@kernel.org, robh@kernel.org, conor+dt@kernel.org, devicetree@vger.kernel.org, broonie@kernel.org, lee@kernel.org, Frank.Li@nxp.com, lgirdwood@gmail.com Cc: vikash.bansal@nxp.com, priyanka.jain@nxp.com, aman.kumarpandey@nxp.com, lakshay.piplani@nxp.com Subject: [PATCH v8 2/7] i3c: master: Add the APIs to support I3C hub Date: Mon, 23 Mar 2026 11:57:32 +0530 Message-Id: <20260323062737.886728-3-lakshay.piplani@nxp.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20260323062737.886728-1-lakshay.piplani@nxp.com> References: <20260323062737.886728-1-lakshay.piplani@nxp.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Virus-Scanned: ClamAV using ClamSMTP Content-Type: text/plain; charset="utf-8" From: Aman Kumar Pandey Add simple helpers to direct attach/detach I3C devices and two CCC helpers to check CCC support and send CCC commands. These additions prepare the master core for I3C hub support. 1) i3c_master_direct_attach_i3c_dev() 2) i3c_master_direct_detach_i3c_dev() 3) i3c_master_send_ccc_cmd() 4) i3c_master_supports_ccc_cmd() Signed-off-by: Aman Kumar Pandey --- Changes in v8: - No change Changes in v7: - Update commit message to clarify purpose (prepare for I3C hub support) Changes in v6: - Split the patch into two parts: 1) expose the existing API 2) add new APIs. --- --- drivers/i3c/master.c | 103 +++++++++++++++++++++++++++++++++++++ include/linux/i3c/master.h | 8 +++ 2 files changed, 111 insertions(+) diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c index 2a12fbb67ba3..500afd8296d1 100644 --- a/drivers/i3c/master.c +++ b/drivers/i3c/master.c @@ -1619,6 +1619,59 @@ static int i3c_master_attach_i3c_dev(struct i3c_mast= er_controller *master, return 0; } =20 +/** + * i3c_master_direct_attach_i3c_dev() - attach an I3C device to a master + * @master: I3C master controller to attach the device to + * @dev: I3C device descriptor representing the device + * + * This function attaches an I3C device to its master controller once the + * device has a valid address on the bus. Devices without + * an assigned address are ignored. The master device itself is never + * attached through this bus. + * + * Return: 0 on success, or a negative error code if the attach operation + * fails in the master controller driver. + */ +int i3c_master_direct_attach_i3c_dev(struct i3c_master_controller *master, + struct i3c_dev_desc *dev) +{ + int ret =3D 0; + + /* + * We don't attach devices to the controller until they are + * addressable on the bus. + */ + + if (!dev->info.static_addr && !dev->info.dyn_addr) + return -EINVAL; + + /* Do not attach the master device itself. */ + if (master->this !=3D dev && master->ops->attach_i3c_dev) + ret =3D master->ops->attach_i3c_dev(dev); + + return ret; +} +EXPORT_SYMBOL_GPL(i3c_master_direct_attach_i3c_dev); + +/** + * i3c_master_direct_detach_i3c_dev - Detach an I3C device from its master + * @dev: I3C device descriptor to be detached + * + * This function detaches an I3C device from its master controller. + * It ensures that the master itself is not detached. If the device is not + * the master and the master controller provides a detach operation, + * the detach callback is invoked to perform the actual removal. + */ +void i3c_master_direct_detach_i3c_dev(struct i3c_dev_desc *dev) +{ + struct i3c_master_controller *master =3D i3c_dev_get_master(dev); + + /* Do not detach the master device itself. */ + if (master->this !=3D dev && master->ops->detach_i3c_dev) + master->ops->detach_i3c_dev(dev); +} +EXPORT_SYMBOL_GPL(i3c_master_direct_detach_i3c_dev); + /** * i3c_master_reattach_i3c_dev() - reattach an I3C device with a new addre= ss * @dev: I3C device descriptor to reattach @@ -1783,6 +1836,56 @@ i3c_master_register_new_i3c_devs(struct i3c_master_c= ontroller *master) } } =20 +/** + * i3c_master_supports_ccc_cmd() - check CCC command support + * @master: I3C master controller + * @cmd: CCC command to verify + * + * This function verifies whether the given I3C master controller supports + * the specified Common Command Code (CCC). + * + * Return: 0 if the CCC command is supported and executed successfully, + * -EINVAL if arguments are invalid, + * -EOPNOTSUPP if the master does not support CCC commands, + * or another negative error code from the master's operation. + */ +int i3c_master_supports_ccc_cmd(struct i3c_master_controller *master, + const struct i3c_ccc_cmd *cmd) +{ + if (!cmd || !master) + return -EINVAL; + + if (!master->ops->supports_ccc_cmd) + return -EOPNOTSUPP; + + return master->ops->supports_ccc_cmd(master, cmd); +} +EXPORT_SYMBOL_GPL(i3c_master_supports_ccc_cmd); + +/** + * i3c_master_send_ccc_cmd() - send a CCC command + * @master: I3C master controller issuing the command + * @cmd: CCC command to be sent + * + * This function sends a Common Command Code (CCC) command to devices on t= he + * I3C bus. It acquires the bus maintenance lock, executes the command, and + * then releases the lock to ensure safe access to the bus. + * + * Return: 0 on success, or a negative error code on failure. + */ +int i3c_master_send_ccc_cmd(struct i3c_master_controller *master, + struct i3c_ccc_cmd *cmd) +{ + int ret; + + i3c_bus_maintenance_lock(&master->bus); + ret =3D i3c_master_send_ccc_cmd_locked(master, cmd); + i3c_bus_maintenance_unlock(&master->bus); + + return ret; +} +EXPORT_SYMBOL_GPL(i3c_master_send_ccc_cmd); + /** * i3c_master_do_daa_ext() - Dynamic Address Assignment (extended version) * @master: controller diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h index aeccec171e64..c00f0918394c 100644 --- a/include/linux/i3c/master.h +++ b/include/linux/i3c/master.h @@ -615,6 +615,14 @@ DEFINE_FREE(i3c_master_dma_unmap_single, void *, =20 int i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev, u8 old_dyn_addr); +int i3c_master_direct_attach_i3c_dev(struct i3c_master_controller *master, + struct i3c_dev_desc *dev); +void i3c_master_direct_detach_i3c_dev(struct i3c_dev_desc *dev); +int i3c_master_send_ccc_cmd(struct i3c_master_controller *master, + struct i3c_ccc_cmd *cmd); + +int i3c_master_supports_ccc_cmd(struct i3c_master_controller *master, + const struct i3c_ccc_cmd *cmd); int i3c_master_set_info(struct i3c_master_controller *master, const struct i3c_device_info *info); =20 --=20 2.25.1