Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1693442

Re: [PATCH v2 04/10] mmc: sunxi: Support controllers that can use both old and new timings

Path csiph.com!news.redatomik.org!aioe.org!bofh.it!news.nic.it!robomod
From Maxime Ripard <maxime.ripard@free-electrons.com>
Newsgroups linux.kernel
Subject Re: [PATCH v2 04/10] mmc: sunxi: Support controllers that can use both old and new timings
Date Fri, 21 Jul 2017 09:30:02 +0200
Message-ID <u5AxQ-1LL-3@gated-at.bofh.it> (permalink)
References <u5aDn-1w5-3@gated-at.bofh.it> <u5aDp-1w5-17@gated-at.bofh.it>
MIME-Version 1.0
Content-Type multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="5aoxigudzrnhotcx"
Content-Disposition inline
User-Agent NeoMutt/20170714 (1.8.3)
Sender robomod@news.nic.it
List-ID <linux-kernel.vger.kernel.org>
X-Mailing-List linux-kernel@vger.kernel.org
Approved robomod@news.nic.it
Lines 52
Organization linux.* mail to news gateway
X-Original-Cc Ulf Hansson <ulf.hansson@linaro.org>, Michael Turquette <mturquette@baylibre.com>, Stephen Boyd <sboyd@codeaurora.org>, Rob Herring <robh+dt@kernel.org>, Mark Rutland <mark.rutland@arm.com>, linux-arm-kernel@lists.infradead.org, linux-mmc@vger.kernel.org, linux-clk@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sunxi@googlegroups.com
X-Original-Date Fri, 21 Jul 2017 09:20:39 +0200
X-Original-Message-ID <20170721072039.qsko2vtradiosdqk@flea>
X-Original-References <20170720034452.15920-1-wens@csie.org> <20170720034452.15920-5-wens@csie.org>
X-Original-Sender linux-kernel-owner@vger.kernel.org
Xref csiph.com linux.kernel:1693442

Show key headers only | View raw


[Multipart message — attachments visible in raw view] - view raw

On Thu, Jul 20, 2017 at 11:44:46AM +0800, Chen-Yu Tsai wrote:
> On the SoCs that introduced the new timing mode for MMC controllers,
> both the old (where the clock delays are set in the CCU) and new
> (where the clock delays are set in the MMC controller) timing modes
> are available, and we have to support them both. However there are
> two bits that control which mode is active. One is in the CCU, the
> other is in the MMC controller. The settings on both sides must be
> the same, or nothing will work.
> 
> The sunxi-ng clock driver provides an API to query and set the
> active timing mode. At probe time, we try to set the active mode
> to the "new timing mode". If it succeeds, we can then use the MMC
> controller in the new mode. If not, we fall back to the old mode.
> 
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>

Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>

Thanks!
Maxime
-- 
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com

Back to linux.kernel | Previous | NextPrevious in thread | Find similar | Unroll thread


Thread

[PATCH v2 04/10] mmc: sunxi: Support controllers that can use both old and new timings Chen-Yu Tsai <wens@csie.org> - 2017-07-20 05:50 +0200
  Re: [PATCH v2 04/10] mmc: sunxi: Support controllers that can use  both old and new timings Maxime Ripard <maxime.ripard@free-electrons.com> - 2017-07-21 09:30 +0200

csiph-web