linux-kernel - Re: [PATCH v4] i2c: designware: Do not require clock when SSCN and FFCN are provided

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20160104161525.GC1599@katana>
Date:	Mon, 4 Jan 2016 17:15:25 +0100
From:	Wolfram Sang <wsa@...-dreams.de>
To:	Suravee Suthikulpanit <Suravee.Suthikulpanit@....com>
Cc:	mika.westerberg@...ux.intel.com, jarkko.nikula@...ux.intel.com,
	andriy.shevchenko@...ux.intel.com, lho@....com, Ken.Xue@....com,
	linux-i2c@...r.kernel.org, linux-acpi@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v4] i2c: designware: Do not require clock when SSCN and
 FFCN are provided

On Mon, Jan 04, 2016 at 09:17:35AM -0600, Suravee Suthikulpanit wrote:
> The current driver uses input clock source frequency to calculate
> values for [SS|FS]_[HC|LC] registers. However, when booting ACPI, we do not
> currently have a good way to provide the frequency information.
> Instead, we can leverage the SSCN and FFCN ACPI methods, which can be used
> to directly provide these values. So, the clock information should
> no longer be required during probing.
> 
> However, since clk can be invalid, additional checks must be done where
> we are making use of it.
> 
> Signed-off-by: Mika Westerberg <mika.westerberg@...ux.intel.com>
> Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@....com>
> Tested-by: Loc Ho <lho@....com> 
> ---
> 
> Note: This has been tested on AMD Seattle RevB for both DT and ACPI.
> 
> Changes from V3 (https://lkml.org/lkml/2015/12/22/596):
>     * Add i2c_dw_plat_prepare_clk() per Andy's suggestion
>     * Add tested-by Loc Ho.

The changes from V3 are big enough that I'd appreciate a new Tested-by
tag.


Download attachment "signature.asc" of type "application/pgp-signature" (820 bytes)