From mboxrd@z Thu Jan 1 00:00:00 1970 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 DB4B0C433EF for ; Sun, 30 Jan 2022 15:11:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1355372AbiA3PLR (ORCPT ); Sun, 30 Jan 2022 10:11:17 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36554 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349175AbiA3PLN (ORCPT ); Sun, 30 Jan 2022 10:11:13 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5E9D6C061714; Sun, 30 Jan 2022 07:11:13 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E8ADB6123B; Sun, 30 Jan 2022 15:11:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E9DDEC340E4; Sun, 30 Jan 2022 15:11:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1643555472; bh=oYvKAImQNUHKveacXyI4MjLN9QGhpLq3yA19e/9Eri8=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=NreeKZBiXnASrKDL6r3UzlLBbK4CgrRFna25soR7h/Q1u7RhIMSmf2IJLhKaBfXGU /zXrkRPbJNSKfD5YCS1Kx0SwJl1qmawCgqOgzYAS0/iM3C9+dL+maAhXXw1XaTsbL8 o9YczUxPc05DfRlQN2yt3XoArE/+ASqQqlz4mhCych6rZKmauHj4RusfKbIoeeJRLN ZGcoC/OtZ6e3+SlRNRyIEs4gT7kNWlO3wruFk6YlkLwsVdzhDqlYWnK+V2Hc6E2G3O 0uLXaSiPOaKYMKpjeMHLLWzUh61NpwtRQFSsLrI3h+qmgIk6fr7y9RUlTsoKXhueg4 JF8D+dpHx9E1Q== Date: Sun, 30 Jan 2022 15:17:37 +0000 From: Jonathan Cameron To: Nikos Latmos Cc: jmaneyrol@invensense.com, lars@metafoo.de, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PROBLEM]: Error during probing process in inv_icm42600_i2c driver Message-ID: <20220130151737.43ef5b08@jic23-huawei> In-Reply-To: References: <20211208135644.3523024-1-n.latmos@deepsea.ai> X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 8 Dec 2021 16:33:52 +0200 Nikos Latmos wrote: > Hello, > > I have an ARM device based on the Broadcom BCM2837 processor (quad-core > ARM Cortex-A53, 1.2GHz), which has an Invensense ICM-42605 IMU chip > connected over I2C. I'm running an unmodified Linux 5.4.83 kernel. The I2C > driver for my device is in the following path: > drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c. > > The problem is that the device driver cannot be probed. More specifically, > dmesg returns the following error message: > > inv-icm42600-i2c 0-0068: mounting matrix not found: using identity... > inv-icm42600-i2c 0-0068: 0-0068 supply vdd not found, using dummy regulator > inv-icm42600-i2c 0-0068: 0-0068 supply vddio not found, using dummy regulator > inv-icm42600-i2c: probe of 0-0068 failed with error -121 > > During the debugging procedure, I found out that the failure occurred when > the driver tried to set up the I2C bus parameters. More precisely, by setting > the INV_ICM42600_REG_INTF_CONFIG6 register according to the values described > in the datasheet for the I2C communication, actually caused the probe function > to fail and return the error -121. > > After I experimented with different values in the specific register bits, > I came to the conclusion, that the setting of the bit > INV_ICM42600_INTF_CONFIG6_I3C_SDR_EN caused the system to successfully > probe the driver. Any other bit setting combinations failed to do so. > > Any hints on why would the driver behave so? > > Here is a patch that I have so far and it seems to solve the issue. > > Best regards, > Nick Latmos Hi All, Anyone familiar with this part able to help Nick? Thanks, Jonathan > > > From d7b3922cd0182ba880ff729edb4a156b55dfb6f0 Mon Sep 17 00:00:00 2001 > From: nicklat > Date: Wed, 8 Dec 2021 15:51:28 +0200 > Subject: [PATCH] iio: imu: inv_icm42600: enable SDR mode > > Add SDR (Single Data Rate) support. > In SDR mode, data is only clocked on one edge of the clock. > > Without this option enabled, the probing process fails. > > Signed-off-by: nicklat > --- > drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c > b/drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c > index 85b1934cec60..ea31f102fbca 100644 > --- a/drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c > +++ b/drivers/iio/imu/inv_icm42600/inv_icm42600_i2c.c > @@ -21,7 +21,8 @@ static int inv_icm42600_i2c_bus_setup(struct > inv_icm42600_state *st) > /* setup interface registers */ > ret = regmap_update_bits(st->map, INV_ICM42600_REG_INTF_CONFIG6, > INV_ICM42600_INTF_CONFIG6_MASK, > - INV_ICM42600_INTF_CONFIG6_I3C_EN); > + INV_ICM42600_INTF_CONFIG6_I3C_EN | > + INV_ICM42600_INTF_CONFIG6_I3C_SDR_EN); > if (ret) > return ret; > > -- > 2.25.1