From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Subject: Re: [PATCHv2 0/4] ACPI / LPSS: Solution for two issues seen on Asus T100 Date: Thu, 15 May 2014 17:53:30 +0300 Message-ID: <1400165610.3703.41.camel@smile.fi.intel.com> References: <1400161226-24067-1-git-send-email-heikki.krogerus@linux.intel.com> <5374D0A8.2090407@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from mga09.intel.com ([134.134.136.24]:49178 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751506AbaEOOxi (ORCPT ); Thu, 15 May 2014 10:53:38 -0400 In-Reply-To: <5374D0A8.2090407@linux.intel.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Li, Aubrey" Cc: Heikki Krogerus , "Rafael J. Wysocki" , Mike Turquette , Mika Westerberg , Jin Yao , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org On Thu, 2014-05-15 at 22:35 +0800, Li, Aubrey wrote: > On 2014/5/15 21:40, Heikki Krogerus wrote: > > Changes since v1: > > - now using do_div() in clk_fd_recalc_rate() as suggested by Andy > > - NULL checks for clk_name allocation in acpi_lpss.c > > > > This combines two patch sets for LPSS that I had already send for > > review separately. They conflicted with each other. > > > > The first two patches will fix a problem were the context of the > > private LPSS registers is lost when entering D3. The last two will add > > support for the M/N dividers on LPSS by adding a new basic clock type > > for fractional dividers. The UART driver needs support for it in order > > to get clock rates that suit the requested baud rates. > > The major issue in my mind is, this proposal makes a couple between I2C > designware, HSUART, or probably DMA driver as well with LPSS driver. acpi_lpss driver creates platform devices for each found and enumerated device. If there no acpi_lpss enabled the drivers work as supposed without it. I didn't see any contradiction here. > That is, currently without LPSS driver, I2C/HSUART won't work properly. > So we at least need to describe this dependency in Kconfig. > > Thanks, > -Aubrey > > > > > > Heikki Krogerus (4): > > ACPI / PM: Export rest of the subsys functions > > ACPI / LPSS: custom power domain for LPSS > > clk: new basic clk type for fractional divider > > ACPI / LPSS: support for fractional divider clock > > > > drivers/acpi/acpi_lpss.c | 204 ++++++++++++++++++++++++++++++----- > > drivers/acpi/device_pm.c | 2 + > > drivers/clk/Makefile | 1 + > > drivers/clk/clk-fractional-divider.c | 135 +++++++++++++++++++++++ > > include/linux/acpi.h | 4 + > > include/linux/clk-provider.h | 31 ++++++ > > 6 files changed, 349 insertions(+), 28 deletions(-) > > create mode 100644 drivers/clk/clk-fractional-divider.c > > > -- Andy Shevchenko Intel Finland Oy