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=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,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 F0978C43143 for ; Tue, 2 Oct 2018 10:41:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AF0AA204FD for ; Tue, 2 Oct 2018 10:41:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AF0AA204FD Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=opensource.cirrus.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727345AbeJBRYP (ORCPT ); Tue, 2 Oct 2018 13:24:15 -0400 Received: from mx0a-001ae601.pphosted.com ([67.231.149.25]:34818 "EHLO mx0b-001ae601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726935AbeJBRYP (ORCPT ); Tue, 2 Oct 2018 13:24:15 -0400 Received: from pps.filterd (m0077473.ppops.net [127.0.0.1]) by mx0a-001ae601.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w92AdZDl029613; Tue, 2 Oct 2018 05:41:35 -0500 Authentication-Results: ppops.net; spf=none smtp.mailfrom=rf@opensource.cirrus.com Received: from mail1.cirrus.com (mail1.cirrus.com [141.131.3.20]) by mx0a-001ae601.pphosted.com with ESMTP id 2mugjdhm6p-1; Tue, 02 Oct 2018 05:41:35 -0500 Received: from EX17.ad.cirrus.com (unknown [172.20.9.81]) by mail1.cirrus.com (Postfix) with ESMTP id 393BA611C8BA; Tue, 2 Oct 2018 05:41:35 -0500 (CDT) Received: from imbe.wolfsonmicro.main (198.61.95.81) by EX17.ad.cirrus.com (172.20.9.81) with Microsoft SMTP Server id 14.3.408.0; Tue, 2 Oct 2018 11:41:34 +0100 Received: from edi-sw-dsktp006.ad.cirrus.com (edi-sw-dsktp006.ad.cirrus.com [198.90.251.121]) by imbe.wolfsonmicro.main (8.14.4/8.14.4) with ESMTP id w92AfYlF022871; Tue, 2 Oct 2018 11:41:34 +0100 From: Richard Fitzgerald To: CC: , , "Richard Fitzgerald" Subject: [PATCH v2 1/2] mfd: madera: Increase wait time for silicon reset Date: Tue, 2 Oct 2018 11:41:33 +0100 Message-ID: <20181002104134.29003-1-rf@opensource.cirrus.com> X-Mailer: git-send-email 2.11.0 MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1810020106 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Based on latest silicon validation, we should allow at least 2 milliseconds after DCVDD enable or hard reset before trying to communicate with the silicon. Previously the delay was done as a side-effect of madera_disable_hard_reset(). As we also need this delay when enabling DCVDD (with or without hard reset) it is better for it to be obvious where it happens in every power-up sequence rather than hidden within another call in some cases. So it has been moved out into a separate function call. Signed-off-by: Richard Fitzgerald --- drivers/mfd/madera-core.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/mfd/madera-core.c b/drivers/mfd/madera-core.c index 440030cecbbd..1dedfe68a3dc 100644 --- a/drivers/mfd/madera-core.c +++ b/drivers/mfd/madera-core.c @@ -135,6 +135,15 @@ EXPORT_SYMBOL_GPL(madera_name_from_type); #define MADERA_BOOT_POLL_INTERVAL_USEC 5000 #define MADERA_BOOT_POLL_TIMEOUT_USEC 25000 +static void madera_por_delay(void) +{ + /* + * Delay after DCVDD enable or hard reset to allow for silicon POR + * (power-on reset). + */ + usleep_range(2000, 3000); +} + static int madera_wait_for_boot(struct madera *madera) { ktime_t timeout; @@ -209,7 +218,6 @@ static void madera_disable_hard_reset(struct madera *madera) return; gpiod_set_raw_value_cansleep(madera->pdata.reset, 1); - usleep_range(1000, 2000); } static int __maybe_unused madera_runtime_resume(struct device *dev) @@ -225,6 +233,8 @@ static int __maybe_unused madera_runtime_resume(struct device *dev) return ret; } + madera_por_delay(); + regcache_cache_only(madera->regmap, false); regcache_cache_only(madera->regmap_32bit, false); @@ -440,6 +450,7 @@ int madera_dev_init(struct madera *madera) } madera_disable_hard_reset(madera); + madera_por_delay(); regcache_cache_only(madera->regmap, false); regcache_cache_only(madera->regmap_32bit, false); -- 2.11.0