From: Barry Song <barry.s...@csr.com>

1ms busy-loop might be wasted when the condition "if(sdhci_readl(host,
SDHCI_PRESENT_STATE) & mask)" becomes false just after the if().
here we use time_after which will have no redundant busy-wait loop.

Signed-off-by: Barry Song <barry.s...@csr.com>
Cc: Bin Shi <bin....@csr.com>
---
 drivers/mmc/host/sdhci.c |   10 ++++------
 1 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index aac92bd..52f5289 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1036,9 +1036,6 @@ void sdhci_send_command(struct sdhci_host *host, struct 
mmc_command *cmd)
 
        WARN_ON(host->cmd);
 
-       /* Wait max 10 ms */
-       timeout = 10;
-
        mask = SDHCI_CMD_INHIBIT;
        if ((cmd->data != NULL) || (cmd->flags & MMC_RSP_BUSY))
                mask |= SDHCI_DATA_INHIBIT;
@@ -1048,8 +1045,11 @@ void sdhci_send_command(struct sdhci_host *host, struct 
mmc_command *cmd)
        if (host->mrq->data && (cmd == host->mrq->data->stop))
                mask &= ~SDHCI_DATA_INHIBIT;
 
+       /* Wait max 10 ms */
+       timeout = jiffies + msecs_to_jiffies(10);
+
        while (sdhci_readl(host, SDHCI_PRESENT_STATE) & mask) {
-               if (timeout == 0) {
+               if (time_after(jiffies, timeout)) {
                        pr_err("%s: Controller never released "
                                "inhibit bit(s).\n", mmc_hostname(host->mmc));
                        sdhci_dumpregs(host);
@@ -1057,8 +1057,6 @@ void sdhci_send_command(struct sdhci_host *host, struct 
mmc_command *cmd)
                        tasklet_schedule(&host->finish_tasklet);
                        return;
                }
-               timeout--;
-               mdelay(1);
        }
 
        mod_timer(&host->timer, jiffies + 10 * HZ);
-- 
1.7.5.4

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