From patchwork Thu Feb 20 17:24:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wolfram Sang X-Patchwork-Id: 204532 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C9277C11D15 for ; Thu, 20 Feb 2020 17:26:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A1F7924673 for ; Thu, 20 Feb 2020 17:26:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728410AbgBTR0F (ORCPT ); Thu, 20 Feb 2020 12:26:05 -0500 Received: from sauhun.de ([88.99.104.3]:35170 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728858AbgBTRZ5 (ORCPT ); Thu, 20 Feb 2020 12:25:57 -0500 Received: from localhost (p5486CC48.dip0.t-ipconnect.de [84.134.204.72]) by pokefinder.org (Postfix) with ESMTPSA id 721632C1EC5; Thu, 20 Feb 2020 18:25:54 +0100 (CET) From: Wolfram Sang To: linux-i2c@vger.kernel.org Cc: linux-renesas-soc@vger.kernel.org, linux-i3c@lists.infradead.org, Kieran Bingham , =?utf-8?q?Niklas_S=C3=B6derlund?= , Luca Ceresoli , Jacopo Mondi , Laurent Pinchart , Vladimir Zapolskiy , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Wolfram Sang Subject: [RFC PATCH 7/7] i2c: core: hand over reserved devices when requesting ancillary addresses Date: Thu, 20 Feb 2020 18:24:03 +0100 Message-Id: <20200220172403.26062-8-wsa+renesas@sang-engineering.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200220172403.26062-1-wsa+renesas@sang-engineering.com> References: <20200220172403.26062-1-wsa+renesas@sang-engineering.com> MIME-Version: 1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org With i2c_new_ancillary_address, we can check if the intended driver is requesting a reserved address. Update the function to do these checks. If the check passes, the "reserved" device will become a regular "dummy" device. Signed-off-by: Wolfram Sang --- drivers/i2c/i2c-core-base.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 4000a4384306..ba325f8107a3 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -975,6 +975,8 @@ struct i2c_client *i2c_new_ancillary_device(struct i2c_client *client, u16 default_addr) { struct device_node *np = client->dev.of_node; + struct device *reserved_dev, *adapter_dev = &client->adapter->dev; + struct i2c_client *reserved_client; u32 addr = default_addr; int i; @@ -984,7 +986,21 @@ struct i2c_client *i2c_new_ancillary_device(struct i2c_client *client, of_property_read_u32_index(np, "reg", i, &addr); } - dev_dbg(&client->adapter->dev, "Address for %s : 0x%x\n", name, addr); + dev_info(adapter_dev, "Address for %s : 0x%x\n", name, addr); + + /* No need to scan muxes, siblings must sit on the same adapter */ + reserved_dev = device_find_child(adapter_dev, &addr, __i2c_check_addr_busy); + reserved_client = i2c_verify_client(reserved_dev); + + if (reserved_client) { + if (reserved_client->dev.of_node != np || + strcmp(reserved_client->name, I2C_RESERVED_DRV_NAME) != 0) + return ERR_PTR(-EBUSY); + + strlcpy(reserved_client->name, I2C_DUMMY_DRV_NAME, sizeof(client->name)); + return reserved_client; + } + return i2c_new_dummy_device(client->adapter, addr); } EXPORT_SYMBOL_GPL(i2c_new_ancillary_device);