From patchwork Wed Mar 18 15:00:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wolfram Sang X-Patchwork-Id: 11445437 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1442C1874 for ; Wed, 18 Mar 2020 15:01:30 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E73F22077D for ; Wed, 18 Mar 2020 15:01:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Zn1FSjsp" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E73F22077D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=sang-engineering.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-i3c-bounces+linux-i3c=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=WPQKPA8x8t8++QchXzGeJFu1YDS+ULBafWAJ/TLr/OU=; b=Zn1FSjspkjrksy 9NLv389R/kASkEHhJMagri9EGU8LrI9LWCx9cVvOTZ+/GCcSBtS1UhcenXVgAzvKUowb6bpAvGoAv MN8qI5+dacliPvvrAyePXxnsVdYirX+4RAEwjP4xRKxhwC97DAGJHJIWXQjGQs+3r9AIwNLN6gb+s p29Bym4dwzC6eMJ7OCTHPTQB3DeCVWOS5NI/25rCmia0GOF9F2fppqp0tJT+ZXFoehEkda8kXNfOI G9rk4Pnl2nYjXvVqxUF2kNjI9G3s+NWZwcp50PU3DHffpdfcZ1y9v2z1mGtT0RzzEiZgKTNaxG2ps //S4G4L0Bs9GPEHq/RJw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jEaCE-0001Up-In; Wed, 18 Mar 2020 15:01:26 +0000 Received: from sauhun.de ([88.99.104.3] helo=pokefinder.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jEaBw-0000Wx-Kg for linux-i3c@lists.infradead.org; Wed, 18 Mar 2020 15:01:10 +0000 Received: from localhost (p54B333FA.dip0.t-ipconnect.de [84.179.51.250]) by pokefinder.org (Postfix) with ESMTPSA id B29E42C2E79; Wed, 18 Mar 2020 16:01:05 +0100 (CET) From: Wolfram Sang To: linux-i2c@vger.kernel.org Subject: [RFC PATCH v2 2/6] i2c: allow DT nodes without 'compatible' Date: Wed, 18 Mar 2020 16:00:55 +0100 Message-Id: <20200318150059.21714-3-wsa+renesas@sang-engineering.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200318150059.21714-1-wsa+renesas@sang-engineering.com> References: <20200318150059.21714-1-wsa+renesas@sang-engineering.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200318_080108_977694_C10A876D X-CRM114-Status: GOOD ( 13.01 ) X-Spam-Score: 1.0 (+) X-Spam-Report: SpamAssassin version 3.4.3 on bombadil.infradead.org summary: Content analysis details: (1.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [88.99.104.3 listed in list.dnswl.org] 0.0 SPF_NONE SPF: sender does not publish an SPF Record -0.0 SPF_HELO_PASS SPF: HELO matches SPF record 1.0 FORGED_SPF_HELO No description available. X-BeenThere: linux-i3c@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux I3C List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Rob Herring , Jacopo Mondi , =?utf-8?q?Niklas_S=C3=B6derlund?= , Geert Uytterhoeven , Wolfram Sang , linux-kernel@vger.kernel.org, Vladimir Zapolskiy , linux-renesas-soc@vger.kernel.org, Kieran Bingham , Laurent Pinchart , Luca Ceresoli , linux-i3c@lists.infradead.org Sender: "linux-i3c" Errors-To: linux-i3c-bounces+linux-i3c=patchwork.kernel.org@lists.infradead.org Sometimes, we have unknown devices in a system and still want to block their address. For that, we allow DT nodes with only a 'reg' property. These devices will be bound to the "dummy" driver but with the name "reserved". That way, we can distinguish them and even hand them over to the "dummy" driver later when they are really requested using i2c_new_ancillary_device(). Signed-off-by: Wolfram Sang Reviewed-by: Geert Uytterhoeven Acked-by: Rob Herring Reviewed-by: Luca Ceresoli Reviewed-by: Kieran Bingham --- Documentation/devicetree/bindings/i2c/i2c-ocores.txt | 2 -- Documentation/devicetree/bindings/i2c/i2c.txt | 4 +++- drivers/i2c/i2c-core-base.c | 1 + drivers/i2c/i2c-core-of.c | 8 +++----- drivers/i2c/i2c-core.h | 1 + 5 files changed, 8 insertions(+), 8 deletions(-) diff --git a/Documentation/devicetree/bindings/i2c/i2c-ocores.txt b/Documentation/devicetree/bindings/i2c/i2c-ocores.txt index 6b25a80ae8d3..fc8ea27934b3 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-ocores.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-ocores.txt @@ -50,7 +50,6 @@ Examples: reg-io-width = <1>; /* 8 bit read/write */ dummy@60 { - compatible = "dummy"; reg = <0x60>; }; }; @@ -68,7 +67,6 @@ or reg-io-width = <1>; /* 8 bit read/write */ dummy@60 { - compatible = "dummy"; reg = <0x60>; }; }; diff --git a/Documentation/devicetree/bindings/i2c/i2c.txt b/Documentation/devicetree/bindings/i2c/i2c.txt index 9a53df4243c6..989b315e09dc 100644 --- a/Documentation/devicetree/bindings/i2c/i2c.txt +++ b/Documentation/devicetree/bindings/i2c/i2c.txt @@ -21,7 +21,9 @@ flags can be attached to the address. I2C_TEN_BIT_ADDRESS is used to mark a 10 bit address. It is needed to avoid the ambiguity between e.g. a 7 bit address of 0x50 and a 10 bit address of 0x050 which, in theory, can be on the same bus. Another flag is I2C_OWN_SLAVE_ADDRESS to mark addresses on which we listen to -be devices ourselves. +be devices ourselves. The 'reg' property of a child is required. The +'compatible' property is not. Empty 'compatible' child entries can be used to +describe unknown devices or addresses which shall be blocked for other reasons. Optional properties ------------------- diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 3d7b8a00a7d9..84464e439df5 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -854,6 +854,7 @@ EXPORT_SYMBOL_GPL(i2c_unregister_device); static const struct i2c_device_id dummy_id[] = { { I2C_DUMMY_DRV_NAME, 0 }, + { I2C_RESERVED_DRV_NAME, 0 }, { }, }; diff --git a/drivers/i2c/i2c-core-of.c b/drivers/i2c/i2c-core-of.c index 6787c1f71483..d8d111ad6c85 100644 --- a/drivers/i2c/i2c-core-of.c +++ b/drivers/i2c/i2c-core-of.c @@ -27,17 +27,15 @@ int of_i2c_get_board_info(struct device *dev, struct device_node *node, memset(info, 0, sizeof(*info)); - if (of_modalias_node(node, info->type, sizeof(info->type)) < 0) { - dev_err(dev, "of_i2c: modalias failure on %pOF\n", node); - return -EINVAL; - } - ret = of_property_read_u32(node, "reg", &addr); if (ret) { dev_err(dev, "of_i2c: invalid reg on %pOF\n", node); return ret; } + if (of_modalias_node(node, info->type, sizeof(info->type)) < 0) + strlcpy(info->type, I2C_RESERVED_DRV_NAME, sizeof(I2C_RESERVED_DRV_NAME)); + if (addr & I2C_TEN_BIT_ADDRESS) { addr &= ~I2C_TEN_BIT_ADDRESS; info->flags |= I2C_CLIENT_TEN; diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h index fb89fabf84d3..77b3a925ed95 100644 --- a/drivers/i2c/i2c-core.h +++ b/drivers/i2c/i2c-core.h @@ -23,6 +23,7 @@ int i2c_dev_irq_from_resources(const struct resource *resources, unsigned int num_resources); #define I2C_DUMMY_DRV_NAME "dummy" +#define I2C_RESERVED_DRV_NAME "reserved" /* * We only allow atomic transfers for very late communication, e.g. to send