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  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:	Tue, 14 Oct 2014 09:39:12 -0700
From:	Doug Anderson <dianders@...omium.org>
To:	Ulf Hansson <ulf.hansson@...aro.org>,
	Seungwon Jeon <tgih.jun@...sung.com>,
	Jaehoon Chung <jh80.chung@...sung.com>
Cc:	Addy Ke <addy.ke@...k-chips.com>,
	Sonny Rao <sonnyrao@...omium.org>,
	Alim Akhtar <alim.akhtar@...sung.com>,
	Andrew Bresticker <abrestic@...omium.org>,
	Doug Anderson <dianders@...omium.org>, heiko@...ech.de,
	chris@...ntf.net, linux-mmc@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	linux-rockchip@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: [PATCH] mmc: dw_mmc: rockchip: Don't recalc the clock when it goes off

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@...omium.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

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists