Use the usleep_range() to simplify mmc_delay() and give some more
accuracy to it - but with an exception of mmc_card_sleepawake():
since sleep/awake timeout varies in a wide range, different
delay methods should be used.

Signed-off-by: Dmitry Antipov <[email protected]>
---
 drivers/mmc/core/core.h    |    8 ++------
 drivers/mmc/core/mmc_ops.c |   12 +++++++++---
 2 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
index 14664f1..a77851e 100644
--- a/drivers/mmc/core/core.h
+++ b/drivers/mmc/core/core.h
@@ -47,12 +47,8 @@ void mmc_power_off(struct mmc_host *host);
 
 static inline void mmc_delay(unsigned int ms)
 {
-       if (ms < 1000 / HZ) {
-               cond_resched();
-               mdelay(ms);
-       } else {
-               msleep(ms);
-       }
+       unsigned long us = ms * USEC_PER_MSEC;
+       usleep_range(us, us + 1000);
 }
 
 void mmc_rescan(struct work_struct *work);
diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c
index 4d41fa9..38d53ac 100644
--- a/drivers/mmc/core/mmc_ops.c
+++ b/drivers/mmc/core/mmc_ops.c
@@ -82,9 +82,15 @@ int mmc_card_sleepawake(struct mmc_host *host, int sleep)
         * SEND_STATUS command to poll the status because that command (and most
         * others) is invalid while the card sleeps.
         */
-       if (!(host->caps & MMC_CAP_WAIT_WHILE_BUSY))
-               mmc_delay(DIV_ROUND_UP(card->ext_csd.sa_timeout, 10000));
-
+       if (!(host->caps & MMC_CAP_WAIT_WHILE_BUSY)) {
+               /* JEDEC MMCA 4.41 specifies the timeout value is in 
200ns..838.86ms
+                  range. Round it up to 1us and use an appropriate delay 
method. */
+               unsigned long us = DIV_ROUND_UP(card->ext_csd.sa_timeout, 10);
+               if (us < 10)
+                       udelay(us);
+               else
+                       usleep_range(us, us + 100);
+       }
        if (!sleep)
                err = mmc_select_card(card);
 
-- 
1.7.7.5

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