From: Jianpeng Ma <majianp...@gmail.com>

With HSMMC_HAS_UPDATED_RESET reset of cmd/data (SRC/SRD) can be to
quick and can be missed resulting in wait for software timeout.
With cpu_relax timeout can be long and unpredictable. Use udelay instead for
timeout implementation.

Reported-by: Yuzheng Ma <mayuzh...@kedacom.com>
Tested-by: Yuzheng Ma <mayuzh...@kedacom.com>
Reviewed-by: Hein Tibosch <hein_tibo...@yahoo.es>
Signed-off-by: Jianpeng Ma <majianp...@gmail.com>
Signed-off-by: Balaji T K <balaj...@ti.com>
---
 drivers/mmc/host/omap_hsmmc.c |   10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index 9ebff99..9f74a57 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -119,7 +119,8 @@
                BRR_EN | BWR_EN | TC_EN | CC_EN)
 
 #define MMC_AUTOSUSPEND_DELAY  100
-#define MMC_TIMEOUT_MS         20
+#define MMC_TIMEOUT_MS         20              /* 20 mSec */
+#define MMC_TIMEOUT_US         20000           /* 20000 micro Sec */
 #define OMAP_MMC_MIN_CLOCK     400000
 #define OMAP_MMC_MAX_CLOCK     52000000
 #define DRIVER_NAME            "omap_hsmmc"
@@ -967,8 +968,7 @@ static inline void omap_hsmmc_reset_controller_fsm(struct 
omap_hsmmc_host *host,
                                                   unsigned long bit)
 {
        unsigned long i = 0;
-       unsigned long limit = (loops_per_jiffy *
-                               msecs_to_jiffies(MMC_TIMEOUT_MS));
+       unsigned long limit = MMC_TIMEOUT_US;
 
        OMAP_HSMMC_WRITE(host->base, SYSCTL,
                         OMAP_HSMMC_READ(host->base, SYSCTL) | bit);
@@ -980,13 +980,13 @@ static inline void omap_hsmmc_reset_controller_fsm(struct 
omap_hsmmc_host *host,
        if (mmc_slot(host).features & HSMMC_HAS_UPDATED_RESET) {
                while ((!(OMAP_HSMMC_READ(host->base, SYSCTL) & bit))
                                        && (i++ < limit))
-                       cpu_relax();
+                       udelay(1);
        }
        i = 0;
 
        while ((OMAP_HSMMC_READ(host->base, SYSCTL) & bit) &&
                (i++ < limit))
-               cpu_relax();
+               udelay(1);
 
        if (OMAP_HSMMC_READ(host->base, SYSCTL) & bit)
                dev_err(mmc_dev(host->mmc),
-- 
1.7.5.4

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