From patchwork Tue Oct 24 22:30:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Packham X-Patchwork-Id: 737666 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 4FD12C07545 for ; Tue, 24 Oct 2023 22:31:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344600AbjJXWbc (ORCPT ); Tue, 24 Oct 2023 18:31:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44130 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344597AbjJXWbX (ORCPT ); Tue, 24 Oct 2023 18:31:23 -0400 Received: from gate2.alliedtelesis.co.nz (gate2.alliedtelesis.co.nz [202.36.163.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2304A35B3 for ; Tue, 24 Oct 2023 15:30:41 -0700 (PDT) Received: from svr-chch-seg1.atlnz.lc (mmarshal3.atlnz.lc [10.32.18.43]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by gate2.alliedtelesis.co.nz (Postfix) with ESMTPS id 5BE622C04C7; Wed, 25 Oct 2023 11:30:35 +1300 (NZDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alliedtelesis.co.nz; s=mail181024; t=1698186635; bh=3bDTzpfSwjO3Sd+/p7MkKEl3QeZJyG1KTOU0ZV9QQAk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1d/46ty3ZwCJ+DaNUgGFlsn/fcCEGxRmMWs9f+CmZiJWmGsUTyj/u9r5uYu7JsXoJ 63QS+4SnQuv1bXBuzbn0zdPivGmSTFK5QjKU28ysQuwykr+0IrlGi9wT+7tGndC4Qx OvXcffDVCWvmDy7aX8sYvLyUn3n4L+TnlyxuiN1ALqBDL2mGE+Dg0AAby0g5niMHA5 3ilHfNxIO1TRy6Xn20opxQfWxj30VHNSdvQuEv7XlpDA1idG/cEvWnWq/R3AerCBVM F8w7CIsgRrhvlX64ZYk3KB+B59aQ6qDSkuBVyp87KL9upO9MsHNapq93Lyowai95ab n7LXxdC0F2Kfw== Received: from pat.atlnz.lc (Not Verified[10.32.16.33]) by svr-chch-seg1.atlnz.lc with Trustwave SEG (v8,2,6,11305) id ; Wed, 25 Oct 2023 11:30:35 +1300 Received: from chrisp-dl.ws.atlnz.lc (chrisp-dl.ws.atlnz.lc [10.33.22.30]) by pat.atlnz.lc (Postfix) with ESMTP id 148DC13EE44; Wed, 25 Oct 2023 11:30:35 +1300 (NZDT) Received: by chrisp-dl.ws.atlnz.lc (Postfix, from userid 1030) id 10F06280820; Wed, 25 Oct 2023 11:30:35 +1300 (NZDT) From: Chris Packham To: gregory.clement@bootlin.com, andi.shyti@kernel.org, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org Cc: linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Chris Packham Subject: [PATCH v4 1/2] dt-bindings: i2c: mv64xxx: add reset-gpios property Date: Wed, 25 Oct 2023 11:30:31 +1300 Message-ID: <20231024223032.3387487-2-chris.packham@alliedtelesis.co.nz> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231024223032.3387487-1-chris.packham@alliedtelesis.co.nz> References: <20231024223032.3387487-1-chris.packham@alliedtelesis.co.nz> MIME-Version: 1.0 X-SEG-SpamProfiler-Analysis: v=2.3 cv=L6ZjvNb8 c=1 sm=1 tr=0 a=KLBiSEs5mFS1a/PbTCJxuA==:117 a=bhdUkHdE2iEA:10 a=KKAkSRfTAAAA:8 a=N1qcaoclDu5WUfG3NQYA:9 a=cvBusfyB2V15izCimMoJ:22 X-SEG-SpamProfiler-Score: 0 x-atlnz-ls: pat Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org Add reset-gpios and reset-duration-us properties to the marvell,mv64xxx-i2c binding. These can be used to describe hardware where a common reset GPIO is connected to all downstream devices on and I2C bus. This reset will be asserted then released before the downstream devices on the bus are probed. Signed-off-by: Chris Packham Reviewed-by: Krzysztof Kozlowski Acked-by: Andi Shyti --- Notes: Changes in v4: - Add r-by from Krzysztof Changes in v3: - Rename reset-delay-us to reset-duration-us to better reflect its purpose - Add default: for reset-duration-us - Add description: for reset-gpios Changes in v2: - Update commit message - Add reset-delay-us property .../devicetree/bindings/i2c/marvell,mv64xxx-i2c.yaml | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/Documentation/devicetree/bindings/i2c/marvell,mv64xxx-i2c.yaml b/Documentation/devicetree/bindings/i2c/marvell,mv64xxx-i2c.yaml index 461d1c9ee3f7..ecf5b279cfa4 100644 --- a/Documentation/devicetree/bindings/i2c/marvell,mv64xxx-i2c.yaml +++ b/Documentation/devicetree/bindings/i2c/marvell,mv64xxx-i2c.yaml @@ -70,6 +70,16 @@ properties: resets: maxItems: 1 + reset-gpios: + description: + GPIO pin providing a common reset for all downstream devices. This GPIO + will be asserted then released before the downstream devices are probed. + maxItems: 1 + + reset-duration-us: + description: Reset duration in us. + default: 1 + dmas: items: - description: RX DMA Channel From patchwork Tue Oct 24 22:30:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Packham X-Patchwork-Id: 737667 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 70AD5C07545 for ; Tue, 24 Oct 2023 22:31:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344584AbjJXWbN (ORCPT ); Tue, 24 Oct 2023 18:31:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41690 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344521AbjJXWbE (ORCPT ); Tue, 24 Oct 2023 18:31:04 -0400 Received: from gate2.alliedtelesis.co.nz (gate2.alliedtelesis.co.nz [IPv6:2001:df5:b000:5::4]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D326D19B2 for ; Tue, 24 Oct 2023 15:30:41 -0700 (PDT) Received: from svr-chch-seg1.atlnz.lc (mmarshal3.atlnz.lc [10.32.18.43]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by gate2.alliedtelesis.co.nz (Postfix) with ESMTPS id 575242C0405; Wed, 25 Oct 2023 11:30:35 +1300 (NZDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alliedtelesis.co.nz; s=mail181024; t=1698186635; bh=u7klOvqa2pZreCyrogOyaNKJgxOLSSqchx8z3orBalU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eYaldgCNb6Y4Om3h1iZ++JrxB/rcMIUvyMpJMhJnO3xJIxlqQH4n/d9R1/qMzko6C 5BsnpoF2pAlp6vdWzmhW/NKbaQFaupeMqD4unzy1e4MxaQ7vjSOTeeA9RUTHiURVQt a5kcg6Pom3sODKu7vWTqTUyJ8LIQRlars25NNaRmOHgKRQNE0ewl0Jahl83ovC0SVL 70BypIwN8vygN9qkxvZhYgK0SYJ0MxvUBjwBV94XqwUren7XZLZ/C0Ab5egNh2nMV2 cmqgHm33Gu3ira7DfOxLX14y7RIZWjvTxZ2mI3tZ0/mKgG/GyTJ7Bri3jF2L4v+xo2 +t2+1THLqWpLA== Received: from pat.atlnz.lc (Not Verified[10.32.16.33]) by svr-chch-seg1.atlnz.lc with Trustwave SEG (v8,2,6,11305) id ; Wed, 25 Oct 2023 11:30:35 +1300 Received: from chrisp-dl.ws.atlnz.lc (chrisp-dl.ws.atlnz.lc [10.33.22.30]) by pat.atlnz.lc (Postfix) with ESMTP id 16A4613EE87; Wed, 25 Oct 2023 11:30:35 +1300 (NZDT) Received: by chrisp-dl.ws.atlnz.lc (Postfix, from userid 1030) id 153E9280820; Wed, 25 Oct 2023 11:30:35 +1300 (NZDT) From: Chris Packham To: gregory.clement@bootlin.com, andi.shyti@kernel.org, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org Cc: linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Chris Packham Subject: [PATCH v4 2/2] i2c: mv64xxx: add an optional reset-gpios property Date: Wed, 25 Oct 2023 11:30:32 +1300 Message-ID: <20231024223032.3387487-3-chris.packham@alliedtelesis.co.nz> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231024223032.3387487-1-chris.packham@alliedtelesis.co.nz> References: <20231024223032.3387487-1-chris.packham@alliedtelesis.co.nz> MIME-Version: 1.0 X-SEG-SpamProfiler-Analysis: v=2.3 cv=L6ZjvNb8 c=1 sm=1 tr=0 a=KLBiSEs5mFS1a/PbTCJxuA==:117 a=bhdUkHdE2iEA:10 a=VsZq4EHS3crWG1I_hwYA:9 X-SEG-SpamProfiler-Score: 0 x-atlnz-ls: pat Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org Some hardware designs have a GPIO used to control the reset of all the devices on and I2C bus. It's not possible for every child node to declare a reset-gpios property as only the first device probed would be able to successfully request it (the others will get -EBUSY). Represent this kind of hardware design by associating the reset-gpios with the parent I2C bus. The reset line will be released prior to the child I2C devices being probed. Signed-off-by: Chris Packham Reviewed-by: Andi Shyti --- Notes: Changes in v4: - Add missing gpio/consumer.h - use fsleep() for enforcing reset-duration Changes in v3: - Rename reset-delay to reset-duration - Use reset-duration-us property to control the reset pulse rather than delaying after the reset Changes in v2: - Add a property to cover the length of delay after releasing the reset GPIO - Use dev_err_probe() when requesing the GPIO fails drivers/i2c/busses/i2c-mv64xxx.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c index efd28bbecf61..a7c6617655f7 100644 --- a/drivers/i2c/busses/i2c-mv64xxx.c +++ b/drivers/i2c/busses/i2c-mv64xxx.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include #include @@ -160,6 +161,7 @@ struct mv64xxx_i2c_data { bool clk_n_base_0; struct i2c_bus_recovery_info rinfo; bool atomic; + struct gpio_desc *reset_gpio; }; static struct mv64xxx_i2c_regs mv64xxx_i2c_regs_mv64xxx = { @@ -1036,6 +1038,7 @@ mv64xxx_i2c_probe(struct platform_device *pd) struct mv64xxx_i2c_data *drv_data; struct mv64xxx_i2c_pdata *pdata = dev_get_platdata(&pd->dev); struct resource *res; + u32 reset_duration; int rc; if ((!pdata && !pd->dev.of_node)) @@ -1083,6 +1086,14 @@ mv64xxx_i2c_probe(struct platform_device *pd) if (drv_data->irq < 0) return drv_data->irq; + drv_data->reset_gpio = devm_gpiod_get_optional(&pd->dev, "reset", GPIOD_OUT_HIGH); + if (IS_ERR(drv_data->reset_gpio)) + return dev_err_probe(&pd->dev, PTR_ERR(drv_data->reset_gpio), + "Cannot get reset gpio\n"); + rc = device_property_read_u32(&pd->dev, "reset-duration-us", &reset_duration); + if (rc) + reset_duration = 1; + if (pdata) { drv_data->freq_m = pdata->freq_m; drv_data->freq_n = pdata->freq_n; @@ -1121,6 +1132,11 @@ mv64xxx_i2c_probe(struct platform_device *pd) goto exit_disable_pm; } + if (drv_data->reset_gpio) { + fsleep(reset_duration); + gpiod_set_value_cansleep(drv_data->reset_gpio, 0); + } + rc = request_irq(drv_data->irq, mv64xxx_i2c_intr, 0, MV64XXX_I2C_CTLR_NAME, drv_data); if (rc) {