All of lore.kernel.org
 help / color / mirror / Atom feed
From: Doug Anderson <dianders@chromium.org>
To: Ulf Hansson <ulf.hansson@linaro.org>,
	Seungwon Jeon <tgih.jun@samsung.com>,
	Jaehoon Chung <jh80.chung@samsung.com>
Cc: Addy Ke <addy.ke@rock-chips.com>,
	Sonny Rao <sonnyrao@chromium.org>,
	Alim Akhtar <alim.akhtar@samsung.com>,
	Andrew Bresticker <abrestic@chromium.org>,
	Doug Anderson <dianders@chromium.org>,
	heiko@sntech.de, chris@printf.net, linux-mmc@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: [PATCH] mmc: dw_mmc: rockchip: Don't recalc the clock when it goes off
Date: Tue, 14 Oct 2014 09:39:12 -0700	[thread overview]
Message-ID: <1413304752-7823-1-git-send-email-dianders@chromium.org> (raw)

The "set_ios" function is called with a clock of 0 when the clock is
turning off.  There's no reason to go through all the extra Rockchip
logic (whose goal is to make sure DIV is 0 or 1) in that case.  The
Rockchip logic happened to work because the CCF will pick the lowest
possible rate when you ask it for a clock of 0, but it's silly to go
through all the remuxing and adjusting for no reason.

Signed-off-by: Doug Anderson <dianders@chromium.org>
---
 drivers/mmc/host/dw_mmc-rockchip.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/mmc/host/dw_mmc-rockchip.c b/drivers/mmc/host/dw_mmc-rockchip.c
index f0c2cb1..bbb4ec3 100644
--- a/drivers/mmc/host/dw_mmc-rockchip.c
+++ b/drivers/mmc/host/dw_mmc-rockchip.c
@@ -37,6 +37,9 @@ static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios)
 	unsigned int cclkin;
 	u32 bus_hz;
 
+	if (ios->clock == 0)
+		return;
+
 	/*
 	 * cclkin: source clock of mmc controller
 	 * bus_hz: card interface clock generated by CLKGEN
-- 
2.1.0.rc2.206.gedb03e5


WARNING: multiple messages have this Message-ID (diff)
From: dianders@chromium.org (Doug Anderson)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] mmc: dw_mmc: rockchip: Don't recalc the clock when it goes off
Date: Tue, 14 Oct 2014 09:39:12 -0700	[thread overview]
Message-ID: <1413304752-7823-1-git-send-email-dianders@chromium.org> (raw)

The "set_ios" function is called with a clock of 0 when the clock is
turning off.  There's no reason to go through all the extra Rockchip
logic (whose goal is to make sure DIV is 0 or 1) in that case.  The
Rockchip logic happened to work because the CCF will pick the lowest
possible rate when you ask it for a clock of 0, but it's silly to go
through all the remuxing and adjusting for no reason.

Signed-off-by: Doug Anderson <dianders@chromium.org>
---
 drivers/mmc/host/dw_mmc-rockchip.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/mmc/host/dw_mmc-rockchip.c b/drivers/mmc/host/dw_mmc-rockchip.c
index f0c2cb1..bbb4ec3 100644
--- a/drivers/mmc/host/dw_mmc-rockchip.c
+++ b/drivers/mmc/host/dw_mmc-rockchip.c
@@ -37,6 +37,9 @@ static void dw_mci_rk3288_set_ios(struct dw_mci *host, struct mmc_ios *ios)
 	unsigned int cclkin;
 	u32 bus_hz;
 
+	if (ios->clock == 0)
+		return;
+
 	/*
 	 * cclkin: source clock of mmc controller
 	 * bus_hz: card interface clock generated by CLKGEN
-- 
2.1.0.rc2.206.gedb03e5

             reply	other threads:[~2014-10-14 16:39 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-10-14 16:39 Doug Anderson [this message]
2014-10-14 16:39 ` [PATCH] mmc: dw_mmc: rockchip: Don't recalc the clock when it goes off Doug Anderson
2014-10-16  2:21 ` Jaehoon Chung
2014-10-16  2:21   ` Jaehoon Chung
2014-10-27 14:18 ` Ulf Hansson
2014-10-27 14:18   ` Ulf Hansson

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1413304752-7823-1-git-send-email-dianders@chromium.org \
    --to=dianders@chromium.org \
    --cc=abrestic@chromium.org \
    --cc=addy.ke@rock-chips.com \
    --cc=alim.akhtar@samsung.com \
    --cc=chris@printf.net \
    --cc=heiko@sntech.de \
    --cc=jh80.chung@samsung.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mmc@vger.kernel.org \
    --cc=linux-rockchip@lists.infradead.org \
    --cc=sonnyrao@chromium.org \
    --cc=tgih.jun@samsung.com \
    --cc=ulf.hansson@linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.