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=-6.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS 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 1DF50C43381 for ; Thu, 7 Mar 2019 06:49:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DA29820675 for ; Thu, 7 Mar 2019 06:49:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="JxVqNMzO"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="BVw5wX2H" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726614AbfCGGtq (ORCPT ); Thu, 7 Mar 2019 01:49:46 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:34276 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726057AbfCGGtq (ORCPT ); Thu, 7 Mar 2019 01:49:46 -0500 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 5B96D6074F; Thu, 7 Mar 2019 06:49:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1551941385; bh=h+1H9laOAG0hzNCViY330XOkwBHYt/gYkcAtTq0zoLA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=JxVqNMzO+6JkSj65885c/o70US0zeJGFXjsgIMTXZQVjcd64f2T1paHDGcJDfZ+9V shp4kbgycqG5VP+C+nqw+glStwxWuN+zIZQM6qCBQsElGnm0Ja/1x34RCj2VNotqKe DDbNsc5RYckhVb/H9r6JGCY26FcqMUxboARefEEM= Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.codeaurora.org (Postfix) with ESMTP id A72B16030B; Thu, 7 Mar 2019 06:49:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1551941384; bh=h+1H9laOAG0hzNCViY330XOkwBHYt/gYkcAtTq0zoLA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=BVw5wX2HU7ck8OV2gn+vDiHEvsmjeR0jDBeiHx0lNBTdC8qrd4uTZwmG8TqX8lRSN k560/4y0nLh1IhvHLt9xoSCTe8jlJ2uvro2QVyhKsJH8iumTRotJN56Ry4LAW7A24Q mgrwD93/sprqGBfXIFb2ywp0EyQV2V33O1vdkmK8= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Thu, 07 Mar 2019 12:19:44 +0530 From: Balakrishna Godavarthi To: Stephen Boyd Cc: johan.hedberg@gmail.com, marcel@holtmann.org, mka@chromium.org, linux-kernel@vger.kernel.org, linux-bluetooth@vger.kernel.org, hemantg@codeaurora.org, linux-arm-msm@vger.kernel.org, rjliao@codeaurora.org Subject: Re: [PATCH v1] Bluetooth: hci_qca: Give enough time to ROME controller to bootup. In-Reply-To: <155191158734.20095.15990837191526416248@swboyd.mtv.corp.google.com> References: <20190306162113.8585-1-bgodavar@codeaurora.org> <155191158734.20095.15990837191526416248@swboyd.mtv.corp.google.com> Message-ID: X-Sender: bgodavar@codeaurora.org User-Agent: Roundcube Webmail/1.2.5 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Stepen, On 2019-03-07 04:03, Stephen Boyd wrote: > Quoting Balakrishna Godavarthi (2019-03-06 08:21:13) >> This patch enables enough time to ROME controller to bootup >> after we bring the enable ping out of reset. >> >> Signed-off-by: Balakrishna Godavarthi >> --- > > Any Fixes tag? And maybe some more explanation or background on where > 150 ms sleep comes from would be useful. Was it determined > experimentally or did it come from a datasheet somewhere? Does the time > differ between boards? > [Bala]: this was observed in our stress testing and even the CHIP firmware team confirmed that BT chip required at least 150 ms to boot up. @Rocky to confirm my statement. >> drivers/bluetooth/hci_qca.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c >> index 237aea34b69f..1953b13511e7 100644 >> --- a/drivers/bluetooth/hci_qca.c >> +++ b/drivers/bluetooth/hci_qca.c >> @@ -508,6 +508,8 @@ static int qca_open(struct hci_uart *hu) >> qcadev = serdev_device_get_drvdata(hu->serdev); >> if (qcadev->btsoc_type != QCA_WCN3990) { >> gpiod_set_value_cansleep(qcadev->bt_en, 1); >> + /* Controller needs time to bootup. */ >> + msleep(150); >> } else { >> hu->init_speed = qcadev->init_speed; >> hu->oper_speed = qcadev->oper_speed; -- Regards Balakrishna.