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mmc: sdhci-of-esdhc: poll ESDHC_CLOCK_STABLE bit with udelay

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The loop to poll ESDHC_CLOCK_STABLE bit with mdelay would waste time
because the time to stabilize is much less than 1 ms. This patch is
to use udelay instead to avoid time wasting.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
yangbo lu 2017-04-26 10:45:49 +08:00 committed by Ulf Hansson
parent a04b9b47ae
commit e145ac451e
1 changed files with 4 additions and 5 deletions
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9
drivers/mmc/host/sdhci-of-esdhc.c
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@ -445,7 +445,7 @@ static void esdhc_of_set_clock(struct sdhci_host *host, unsigned int clock)
struct sdhci_esdhc *esdhc = sdhci_pltfm_priv(pltfm_host); struct sdhci_esdhc *esdhc = sdhci_pltfm_priv(pltfm_host);
int pre_div = 1; int pre_div = 1;
int div = 1; int div = 1;
u32 timeout; ktime_t timeout;
u32 temp; u32 temp;
host->mmc->actual_clock = 0; host->mmc->actual_clock = 0;
@ -489,15 +489,14 @@ static void esdhc_of_set_clock(struct sdhci_host *host, unsigned int clock)
sdhci_writel(host, temp, ESDHC_SYSTEM_CONTROL); sdhci_writel(host, temp, ESDHC_SYSTEM_CONTROL);
/* Wait max 20 ms */ /* Wait max 20 ms */
timeout = 20; timeout = ktime_add_ms(ktime_get(), 20);
while (!(sdhci_readl(host, ESDHC_PRSSTAT) & ESDHC_CLOCK_STABLE)) { while (!(sdhci_readl(host, ESDHC_PRSSTAT) & ESDHC_CLOCK_STABLE)) {
if (timeout == 0) { if (ktime_after(ktime_get(), timeout)) {
pr_err("%s: Internal clock never stabilised.\n", pr_err("%s: Internal clock never stabilised.\n",
mmc_hostname(host->mmc)); mmc_hostname(host->mmc));
return; return;
} }
timeout--; udelay(10);
mdelay(1);
} }
temp |= ESDHC_CLOCK_SDCLKEN; temp |= ESDHC_CLOCK_SDCLKEN;