From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752176AbbJWUER (ORCPT ); Fri, 23 Oct 2015 16:04:17 -0400 Received: from sauhun.de ([89.238.76.85]:36676 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751074AbbJWUEO (ORCPT ); Fri, 23 Oct 2015 16:04:14 -0400 Date: Fri, 23 Oct 2015 22:04:07 +0200 From: Wolfram Sang To: Xiang Wang Cc: Andy Shevchenko , Jarkko Nikula , xiang.a.wang@intel.com, linux-i2c@vger.kernel.org, "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 2/2] i2c: designware: enable High-speed mode for pcidrv Message-ID: <20151023200407.GC1520@katana> References: <1444380426-17953-1-git-send-email-wangxfdu@gmail.com> <1444380426-17953-2-git-send-email-wangxfdu@gmail.com> <1444383067.8361.517.camel@linux.intel.com> <1444638708.8361.564.camel@linux.intel.com> <561F64A1.8030805@linux.intel.com> <1444902023.8361.629.camel@linux.intel.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="XMCwj5IQnwKtuyBG" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --XMCwj5IQnwKtuyBG Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > > Should it (ACPI walk) be done in PCI case as well? If so, then it needs > > to be done up to i2c-core. There you may adjust the bus speed whenever > > slave device is enumerated. > > > I think the "ACPI walk for bus speed" also works for PCI case. It'll > be good to do this in i2c-core. > By doing this we can get a minimum device speed for this bus. I2C bus > drivers can use this speed to set corresponding mode into i2c > controller. > Waiting for comments from others. >=20 > > For PCI case you have still to have hardcoded values and it should be > > maximum supported by the bus I think. When you have implemented above > > algorithm you may do this safely. Am I missing something? > Agree. It'll be safer to set a hardcoded maximum supported speed of > the bus for PCI case. > I2C bus driver can use MIN(speed_get_by_ACPI_walk, > hardcoded_max_supported_speed) for bus speed. Do I read this correctly that you agreed on an alternative path so this series can be discarded? --XMCwj5IQnwKtuyBG Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJWKpK3AAoJEBQN5MwUoCm2CAYP/1aFyD3gxxNJPyDHQpuGAIio 8Lcpo14XgsXSy0WDswSHaCPwQzUxIhhArtoZkWyQx2n4WC86K2uY0Dh2LngQe5sI MbbdvTRD+AFNq9TDg9s0JwFGFz5sTE/TWh5EkkAobQpCg4Kwlgu0jxFG4737nKvo Keok5gbBqBuSoss7dbEHWj1uidb3J/6oc7m9nQN5sG6j1v9WTZTT998+ZurvVfA2 fNSrj9Qa7ibW4BAeQoNzzlKo/t+FV53ulcbjkG7cx69Xun0GmxDjWPJBYj92eYLy SAXlx33RKbth6McBUkBG2jvd/cfz1jGRNAh7YzHt+/tx2BUbdbGepSFLAEhgMhmE us4DKtyzfQr97YGso8HHAPk/uOmGybI/z2HM976pjZT0JV3t4gLrQiFHgwqgu1Jl 2iXNcd/wPs4ZabeHGkrQDVO5lIaf1STGYgjlSXPyV2DD9aNjlkZmEF2RFyI3Xler UxgNI+UXx3lDcdscyP4t66wQIkjBj9jHxJmKhHLZDLxdmTRjar0lTQc/80aQDjji pPvDIFLVREDnkHXaXX0nuKmxfgDGYvBOAkSD+JA914s+0N00isb5bZEM5PfXMn59 c1V9uftPSGl5wtQ9lQHXgpx/7U1GqL8XCe0rvgtr3AZ8n3NCDK2JY4Iy6PkAXvWc 9LtcY1lqBLDORj8b2SH+ =L3/H -----END PGP SIGNATURE----- --XMCwj5IQnwKtuyBG--