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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 71D74C433E0 for ; Fri, 5 Mar 2021 01:24:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 22C1064FF0 for ; Fri, 5 Mar 2021 01:24:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229584AbhCEBYK (ORCPT ); Thu, 4 Mar 2021 20:24:10 -0500 Received: from emcscan.emc.com.tw ([192.72.220.5]:24208 "EHLO emcscan.emc.com.tw" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229458AbhCEBYJ (ORCPT ); Thu, 4 Mar 2021 20:24:09 -0500 X-IronPort-AV: E=Sophos;i="5.56,253,1539619200"; d="scan'208";a="39657530" Received: from unknown (HELO webmail.emc.com.tw) ([192.168.10.1]) by emcscan.emc.com.tw with ESMTP; 05 Mar 2021 09:24:08 +0800 Received: from 192.168.10.23 by webmail.emc.com.tw with MailAudit ESMTP Server V5.0(2828:0:AUTH_RELAY) (envelope-from ); Fri, 05 Mar 2021 09:24:05 +0800 (CST) Received: from 192.168.33.11 by webmail.emc.com.tw with Mail2000 ESMTP Server V7.00(2474:1:AUTH_RELAY) (envelope-from ); Fri, 05 Mar 2021 09:24:05 +0800 (CST) From: "jingle" To: "'Dmitry Torokhov'" Cc: "'linux-kernel'" , "'linux-input'" , "'phoenix'" , "'dave.wang'" , "'josh.chen'" References: <20210226073537.4926-1-jingle.wu@emc.com.tw> <1614647097.9201.jingle.wu@emc.com.tw> In-Reply-To: Subject: RE: [PATCH] Input: elan_i2c - Reduce the resume time for new dev ices Date: Fri, 5 Mar 2021 09:24:05 +0800 Message-ID: <004f01d7115e$3ba005e0$b2e011a0$@emc.com.tw> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 14.0 Thread-Index: AQGs01cKeSW+WSlGkCw6sJc3Mb/pawH5MxoQAdwxvXACK2QSBKqZDPmQ Content-Language: zh-tw x-dg-ref: PG1ldGE+PGF0IG5tPSJib2R5LnR4dCIgcD0iYzpcdXNlcnNcMDYwMTFcYXBwZGF0YVxyb2FtaW5nXDA5ZDg0OWI2LTMyZDMtNGE0MC04NWVlLTZiODRiYTI5ZTM1Ylxtc2dzXG1zZy03OTJkN2ViZS03ZDUxLTExZWItOGUwZi1mMDc5NTk2OWU3NWVcYW1lLXRlc3RcNzkyZDdlYzAtN2Q1MS0xMWViLThlMGYtZjA3OTU5NjllNzVlYm9keS50eHQiIHN6PSIxNjgwIiB0PSIxMzI1OTM4MTA0NTM5MzU3NzQiIGg9ImlvQnd0Wnp3K3BFWTdYWDBiaTc1YkdJSVQycz0iIGlkPSIiIGJsPSIwIiBibz0iMSIvPjwvbWV0YT4= x-dg-rorf: true Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org HI Dmitry: In this case (in the newer parts behavior regarding need to reset after powering them on), it is consistent with the original driver behavior with any new or old device (be called data->ops->initialize(client) : usleep(100) , etc.. , because this times "data->quirks" is equal 0 at probe state.) THANKS JINGLE -----Original Message----- From: Dmitry Torokhov [mailto:dmitry.torokhov@gmail.com] Sent: Friday, March 05, 2021 8:55 AM To: jingle.wu Cc: linux-kernel; linux-input; phoenix; dave.wang; josh.chen Subject: Re: [PATCH] Input: elan_i2c - Reduce the resume time for new dev ices Hi Jingle, On Tue, Mar 02, 2021 at 09:04:57AM +0800, jingle.wu wrote: > HI Dmitry: > > So data->ops->initialize(client) essentially performs reset of the > controller (we may want to rename it even) and as far as I understand > you would want to avoid resetting the controller on newer devices, > right? > > -> YES > > My question is how behavior of older devices differ from the new ones > (are they stay in "undefined" state at power up) and whether it is > possible to determine if controller is in operating mode. For example, > what would happen on older devices if we call elan_query_product() > below without resetting the controller? > > -> But there may be other problems, because ELAN can't test all the > -> older devices , so use quirk to divide this part. OK, but could you please tell me what exactly was changed in the newer parts behavior regarding need to reset after powering them on? Thanks. -- Dmitry