If hibern8 enter command fails then UFS link state may be unknown which
may result into timeout of all the commands issued after failure.

This change does 2 things (for pre-defined number of retry counts) after
hibern8 enter failure:
1. Recovers the UFS link to active state
2. If link is recovered to active state, tries to put the UFS link in
   hibern8 enter again until retry count expires.

Reviewed-by: Gilad Broner <gbro...@codeaurora.org>
Reviewed-by: Dolev Raviv <dra...@codeaurora.org>
Signed-off-by: Subhash Jadavani <subha...@codeaurora.org>
Signed-off-by: Yaniv Gardi <yga...@codeaurora.org>

---
 drivers/scsi/ufs/ufshcd.c | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 5005d12..ed134d6 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -76,6 +76,9 @@
 /* maximum number of link-startup retries */
 #define DME_LINKSTARTUP_RETRIES 3
 
+/* Maximum retries for Hibern8 enter */
+#define UIC_HIBERN8_ENTER_RETRIES 3
+
 /* maximum number of reset retries before giving up */
 #define MAX_HOST_RESET_RETRIES 5
 
@@ -2390,13 +2393,32 @@ out:
        return ret;
 }
 
-static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba)
+static int __ufshcd_uic_hibern8_enter(struct ufs_hba *hba)
 {
+       int ret;
        struct uic_command uic_cmd = {0};
 
        uic_cmd.command = UIC_CMD_DME_HIBER_ENTER;
+       ret = ufshcd_uic_pwr_ctrl(hba, &uic_cmd);
+
+       if (ret)
+               dev_err(hba->dev, "%s: hibern8 enter failed. ret = %d\n",
+                       __func__, ret);
+
+       return ret;
+}
+
+static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba)
+{
+       int ret = 0, retries;
 
-       return ufshcd_uic_pwr_ctrl(hba, &uic_cmd);
+       for (retries = UIC_HIBERN8_ENTER_RETRIES; retries > 0; retries--) {
+               ret = __ufshcd_uic_hibern8_enter(hba);
+               if (!ret || ret == -ENOLINK)
+                       goto out;
+       }
+out:
+       return ret;
 }
 
 static int ufshcd_uic_hibern8_exit(struct ufs_hba *hba)
-- 
1.8.5.2

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