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author | Tomasz Figa <tomasz.figa@gmail.com> | 2014-01-11 22:39:02 +0100 |
---|---|---|
committer | Chris Ball <chris@printf.net> | 2014-03-03 16:23:18 +0100 |
commit | 6eb28bdcb27249ca9981fb063d3f2485fd344500 (patch) | |
tree | 689d84356e6e9e9b3f8d44c5ff745d3bb8891b48 /drivers/mmc/host/sdhci-s3c.c | |
parent | mmc: sdhci-s3c: Use shifts to divide by powers of two (diff) | |
download | linux-6eb28bdcb27249ca9981fb063d3f2485fd344500.tar.xz linux-6eb28bdcb27249ca9981fb063d3f2485fd344500.zip |
mmc: sdhci-s3c: Cache bus clock rates
To fix scheduling while atomic happening in sdhci_s3c_set_clock() caused
by calling clk_get_rate() that might sleep, this patch modifies the
driver to cache rates of all bus clocks at probe time and then only use
those cache values.
Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by; Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <chris@printf.net>
Diffstat (limited to 'drivers/mmc/host/sdhci-s3c.c')
-rw-r--r-- | drivers/mmc/host/sdhci-s3c.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/drivers/mmc/host/sdhci-s3c.c b/drivers/mmc/host/sdhci-s3c.c index 52770d58cc47..9b783915b02a 100644 --- a/drivers/mmc/host/sdhci-s3c.c +++ b/drivers/mmc/host/sdhci-s3c.c @@ -57,6 +57,7 @@ struct sdhci_s3c { struct clk *clk_io; struct clk *clk_bus[MAX_BUS_CLK]; + unsigned long clk_rates[MAX_BUS_CLK]; }; /** @@ -158,7 +159,7 @@ static unsigned int sdhci_s3c_consider_clock(struct sdhci_s3c *ourhost, return wanted - rate; } - rate = clk_get_rate(clksrc); + rate = ourhost->clk_rates[src]; for (shift = 0; shift < 8; ++shift) { if ((rate >> shift) <= wanted) @@ -215,7 +216,7 @@ static void sdhci_s3c_set_clock(struct sdhci_host *host, unsigned int clock) writew(0, host->ioaddr + SDHCI_CLOCK_CONTROL); ourhost->cur_clk = best_src; - host->max_clk = clk_get_rate(clk); + host->max_clk = ourhost->clk_rates[best_src]; ctrl = readl(host->ioaddr + S3C_SDHCI_CONTROL2); ctrl &= ~S3C_SDHCI_CTRL2_SELBASECLK_MASK; @@ -583,8 +584,10 @@ static int sdhci_s3c_probe(struct platform_device *pdev) */ sc->cur_clk = ptr; + sc->clk_rates[ptr] = clk_get_rate(sc->clk_bus[ptr]); + dev_info(dev, "clock source %d: %s (%ld Hz)\n", - ptr, name, clk_get_rate(clk)); + ptr, name, sc->clk_rates[ptr]); } if (clks == 0) { |