From patchwork Thu Jan 5 14:03:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tomi Valkeinen X-Patchwork-Id: 639876 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E1061C53210 for ; Thu, 5 Jan 2023 14:03:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234574AbjAEODv (ORCPT ); Thu, 5 Jan 2023 09:03:51 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49408 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233792AbjAEOD2 (ORCPT ); Thu, 5 Jan 2023 09:03:28 -0500 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DC3F840863; Thu, 5 Jan 2023 06:03:26 -0800 (PST) Received: from desky.lan (91-154-32-225.elisa-laajakaista.fi [91.154.32.225]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id E26454AE; Thu, 5 Jan 2023 15:03:23 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1672927405; bh=nzYI/InFnBKeKA+u3WNviBVDcVXlhGM1JMPGchLnOb0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kp+L0TlAtqg51LR37LO/3z6UT+3EhZWHv3Zozz7hDP8oUNXvN2G7BRqfJybPJHao6 YgY8qNfi4xgE4Bv/OlWkl+z5+VvK+LdFuoqutG2F90+ckalIkHeIpUE0APU8vKrW+r 5mgHxBYFRqWgIqZCUMxLmtPyE5c96m1UfspFXDmc= From: Tomi Valkeinen To: linux-media@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, Rob Herring , Krzysztof Kozlowski , Wolfram Sang , Luca Ceresoli , Andy Shevchenko , Matti Vaittinen Cc: Mauro Carvalho Chehab , Peter Rosin , Liam Girdwood , Mark Brown , Sakari Ailus , Laurent Pinchart , Michael Tretter , Shawn Tu , Hans Verkuil , Mike Pagano , =?utf-8?q?Krzysztof_Ha=C5=82asa?= , Marek Vasut , Luca Ceresoli , Tomi Valkeinen Subject: [PATCH v6 1/8] i2c: core: let adapters be notified of client attach/detach Date: Thu, 5 Jan 2023 16:03:00 +0200 Message-Id: <20230105140307.272052-2-tomi.valkeinen@ideasonboard.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230105140307.272052-1-tomi.valkeinen@ideasonboard.com> References: <20230105140307.272052-1-tomi.valkeinen@ideasonboard.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org From: Luca Ceresoli An adapter might need to know when a new device is about to be added. This will soon bee needed to implement an "I2C address translator" (ATR for short), a device that propagates I2C transactions with a different slave address (an "alias" address). An ATR driver needs to know when a slave is being added to find a suitable alias and program the device translation map. Add an attach/detach callback pair to allow adapter drivers to be notified of clients being added and removed. Signed-off-by: Luca Ceresoli Signed-off-by: Tomi Valkeinen --- drivers/i2c/i2c-core-base.c | 21 ++++++++++++++++++++- include/linux/i2c.h | 16 ++++++++++++++++ 2 files changed, 36 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 7539b0740351..8a0888ba89e5 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -916,6 +916,7 @@ int i2c_dev_irq_from_resources(const struct resource *resources, struct i2c_client * i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *info) { + const struct i2c_attach_operations *attach_ops; struct i2c_client *client; int status; @@ -967,15 +968,24 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *inf } } + attach_ops = adap->attach_ops; + + if (attach_ops && attach_ops->attach_client && + attach_ops->attach_client(adap, info, client)) + goto out_remove_swnode; + status = device_register(&client->dev); if (status) - goto out_remove_swnode; + goto out_detach_client; dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", client->name, dev_name(&client->dev)); return client; +out_detach_client: + if (attach_ops && attach_ops->detach_client) + attach_ops->detach_client(adap, client); out_remove_swnode: device_remove_software_node(&client->dev); out_err_put_of_node: @@ -997,9 +1007,18 @@ EXPORT_SYMBOL_GPL(i2c_new_client_device); */ void i2c_unregister_device(struct i2c_client *client) { + const struct i2c_attach_operations *attach_ops; + struct i2c_adapter *adap; + if (IS_ERR_OR_NULL(client)) return; + adap = client->adapter; + attach_ops = adap->attach_ops; + + if (attach_ops && attach_ops->detach_client) + attach_ops->detach_client(adap, client); + if (client->dev.of_node) { of_node_clear_flag(client->dev.of_node, OF_POPULATED); of_node_put(client->dev.of_node); diff --git a/include/linux/i2c.h b/include/linux/i2c.h index f7c49bbdb8a1..9a385b6de388 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -584,6 +584,21 @@ struct i2c_lock_operations { void (*unlock_bus)(struct i2c_adapter *adapter, unsigned int flags); }; +/** + * struct i2c_attach_operations - callbacks to notify client attach/detach + * @attach_client: Notify of new client being attached + * @detach_client: Notify of new client being detached + * + * Both ops are optional. + */ +struct i2c_attach_operations { + int (*attach_client)(struct i2c_adapter *adapter, + const struct i2c_board_info *info, + const struct i2c_client *client); + void (*detach_client)(struct i2c_adapter *adapter, + const struct i2c_client *client); +}; + /** * struct i2c_timings - I2C timing information * @bus_freq_hz: the bus frequency in Hz @@ -726,6 +741,7 @@ struct i2c_adapter { /* data fields that are valid for all devices */ const struct i2c_lock_operations *lock_ops; + const struct i2c_attach_operations *attach_ops; struct rt_mutex bus_lock; struct rt_mutex mux_lock;