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From: tomasz.figa@gmail.com (Tomasz Figa)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 6/6] mmc: sdhci-s3c: Do not allow frequencies higher than requested
Date: Sat, 11 Jan 2014 22:39:06 +0100	[thread overview]
Message-ID: <1389476346-20396-7-git-send-email-tomasz.figa@gmail.com> (raw)
In-Reply-To: <1389476346-20396-1-git-send-email-tomasz.figa@gmail.com>

This patch modifies sdhci_s3c_consider_clock() to fail if bus clock
being considered can not provide frequency lower or equal requested,
instead of returning the lowest supported.

Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
---
 drivers/mmc/host/sdhci-s3c.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-s3c.c b/drivers/mmc/host/sdhci-s3c.c
index bad0e00..d61eb5a 100644
--- a/drivers/mmc/host/sdhci-s3c.c
+++ b/drivers/mmc/host/sdhci-s3c.c
@@ -126,11 +126,18 @@ static unsigned int sdhci_s3c_consider_clock(struct sdhci_s3c *ourhost,
 
 	rate = ourhost->clk_rates[src];
 
-	for (shift = 0; shift < 8; ++shift) {
+	for (shift = 0; shift <= 8; ++shift) {
 		if ((rate >> shift) <= wanted)
 			break;
 	}
 
+	if (shift > 8) {
+		dev_dbg(&ourhost->pdev->dev,
+			"clk %d: rate %ld, min rate %lu > wanted %u\n",
+			src, rate, rate / 256, wanted);
+		return UINT_MAX;
+	}
+
 	dev_dbg(&ourhost->pdev->dev, "clk %d: rate %ld, want %d, got %ld\n",
 		src, rate, wanted, rate >> shift);
 
-- 
1.8.5.2

  parent reply	other threads:[~2014-01-11 21:39 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-01-11 21:39 [PATCH 0/6] mmc: sdhci-s3c: Fix base clock source management Tomasz Figa
2014-01-11 21:39 ` [PATCH 1/6] mmc: sdhci-s3c: Use shifts to divide by powers of two Tomasz Figa
2014-01-11 21:39 ` [PATCH 2/6] mmc: sdhci-s3c: Cache bus clock rates Tomasz Figa
2014-01-11 21:39 ` [PATCH 3/6] mmc: sdhci-s3c: Use correct condition to check for clock presence Tomasz Figa
2014-01-11 21:39 ` [PATCH 4/6] mmc: sdhci-s3c: Simplify min/max clock calculation Tomasz Figa
2014-01-11 21:39 ` [PATCH 5/6] mmc: sdhci-s3c: Fix handling of bus clock switching Tomasz Figa
2014-01-11 21:39 ` Tomasz Figa [this message]
2014-01-12 21:18 ` [PATCH 0/6] mmc: sdhci-s3c: Fix base clock source management Heiko Stübner
2014-01-13  5:47   ` Jaehoon Chung
2014-01-13 12:43     ` Tomasz Figa
2014-02-07  9:58 ` Tomasz Figa
2014-02-20 19:26   ` Tomasz Figa
2014-03-03 15:06     ` Tomasz Figa
2014-03-03 15:24       ` Chris Ball
2014-03-03 15:25         ` Tomasz Figa

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