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 X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 A33DEC28CC1 for ; Sat, 1 Jun 2019 13:30:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7A83627473 for ; Sat, 1 Jun 2019 13:30:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559395830; bh=iKFhaIr8rPvFeRFwneCZtFEEkt+6qqK4mTCTtwCb0eM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=1z9bzdhVKdwYCwWlCGb+fC97UEsYY2eab9dD9iilmyfffxlh/dUSqn/MngnbkRaHr 0SL4RhoNASpWt4x83Kq98GRv9f1nSlr3bAtgkLmyacR/I3V978xOboKZEhiAUEJ2Uz YO99KARoh3DwzsBRV94yo6t1tHT4EzcYLEDstBNY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729829AbfFANaY (ORCPT ); Sat, 1 Jun 2019 09:30:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:56772 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729678AbfFAN0V (ORCPT ); Sat, 1 Jun 2019 09:26:21 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 410E1273B8; Sat, 1 Jun 2019 13:26:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559395581; bh=iKFhaIr8rPvFeRFwneCZtFEEkt+6qqK4mTCTtwCb0eM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EBVDrJbm5dJfs3zy4iFRHeItpW8Jl62qKSyWVjFEh+4yEs4Rfg2qQgN1Li9npDebm wEBrwELOiX2j9GprzrTPKHtwelTE1hFfXRJ0ZLJPTDRFsaM+NoI/+jvcXoM+DB2rsv 6b2yyDWxDxaXl+XRp8K5IQXDC13/HmSQ9gOQ/SLQ= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Tony Lindgren , Peter Ujfalusi , Lee Jones , Sasha Levin , linux-omap@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 09/56] mfd: twl6040: Fix device init errors for ACCCTL register Date: Sat, 1 Jun 2019 09:25:13 -0400 Message-Id: <20190601132600.27427-9-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190601132600.27427-1-sashal@kernel.org> References: <20190601132600.27427-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tony Lindgren [ Upstream commit 48171d0ea7caccf21c9ee3ae75eb370f2a756062 ] I noticed that we can get a -EREMOTEIO errors on at least omap4 duovero: twl6040 0-004b: Failed to write 2d = 19: -121 And then any following register access will produce errors. There 2d offset above is register ACCCTL that gets written on twl6040 powerup. With error checking added to the related regcache_sync() call, the -EREMOTEIO error is reproducable on twl6040 powerup at least duovero. To fix the error, we need to wait until twl6040 is accessible after the powerup. Based on tests on omap4 duovero, we need to wait over 8ms after powerup before register write will complete without failures. Let's also make sure we warn about possible errors too. Note that we have twl6040_patch[] reg_sequence with the ACCCTL register configuration and regcache_sync() will write the new value to ACCCTL. Signed-off-by: Tony Lindgren Acked-by: Peter Ujfalusi Signed-off-by: Lee Jones Signed-off-by: Sasha Levin --- drivers/mfd/twl6040.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/mfd/twl6040.c b/drivers/mfd/twl6040.c index 72aab60ae8466..db8684430f02c 100644 --- a/drivers/mfd/twl6040.c +++ b/drivers/mfd/twl6040.c @@ -316,8 +316,19 @@ int twl6040_power(struct twl6040 *twl6040, int on) } } + /* + * Register access can produce errors after power-up unless we + * wait at least 8ms based on measurements on duovero. + */ + usleep_range(10000, 12000); + /* Sync with the HW */ - regcache_sync(twl6040->regmap); + ret = regcache_sync(twl6040->regmap); + if (ret) { + dev_err(twl6040->dev, "Failed to sync with the HW: %i\n", + ret); + goto out; + } /* Default PLL configuration after power up */ twl6040->pll = TWL6040_SYSCLK_SEL_LPPLL; -- 2.20.1