rtc: opal: Fix OPAL RTC driver OPAL_BUSY loops

[mirror_ubuntu-bionic-kernel.git] / drivers / rtc / rtc-opal.c

diff --git a/drivers/rtc/rtc-opal.c b/drivers/rtc/rtc-opal.c
index 304e891e35fcb060a8ff26f78122fa3c63a1eb87..60f2250fd96bec2cec1dd33f652edaac474d2182 100644 (file)
--- a/drivers/rtc/rtc-opal.c
+++ b/drivers/rtc/rtc-opal.c
@@ -57,7 +57,7 @@ static void tm_to_opal(struct rtc_time *tm, u32 *y_m_d, u64 *h_m_s_ms)
 
 static int opal_get_rtc_time(struct device *dev, struct rtc_time *tm)
 {
-       long rc = OPAL_BUSY;
+       s64 rc = OPAL_BUSY;
        int retries = 10;
        u32 y_m_d;
        u64 h_m_s_ms;
@@ -66,13 +66,17 @@ static int opal_get_rtc_time(struct device *dev, struct rtc_time *tm)
 
        while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
                rc = opal_rtc_read(&__y_m_d, &__h_m_s_ms);
-               if (rc == OPAL_BUSY_EVENT)
+               if (rc == OPAL_BUSY_EVENT) {
+                       msleep(OPAL_BUSY_DELAY_MS);
                        opal_poll_events(NULL);
-               else if (retries-- && (rc == OPAL_HARDWARE
-                                      || rc == OPAL_INTERNAL_ERROR))
-                       msleep(10);
-               else if (rc != OPAL_BUSY && rc != OPAL_BUSY_EVENT)
-                       break;
+               } else if (rc == OPAL_BUSY) {
+                       msleep(OPAL_BUSY_DELAY_MS);
+               } else if (rc == OPAL_HARDWARE || rc == OPAL_INTERNAL_ERROR) {
+                       if (retries--) {
+                               msleep(10); /* Wait 10ms before retry */
+                               rc = OPAL_BUSY; /* go around again */
+                       }
+               }
        }
 
        if (rc != OPAL_SUCCESS)
@@ -87,21 +91,26 @@ static int opal_get_rtc_time(struct device *dev, struct rtc_time *tm)
 
 static int opal_set_rtc_time(struct device *dev, struct rtc_time *tm)
 {
-       long rc = OPAL_BUSY;
+       s64 rc = OPAL_BUSY;
        int retries = 10;
        u32 y_m_d = 0;
        u64 h_m_s_ms = 0;
 
        tm_to_opal(tm, &y_m_d, &h_m_s_ms);
+
        while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
                rc = opal_rtc_write(y_m_d, h_m_s_ms);
-               if (rc == OPAL_BUSY_EVENT)
+               if (rc == OPAL_BUSY_EVENT) {
+                       msleep(OPAL_BUSY_DELAY_MS);
                        opal_poll_events(NULL);
-               else if (retries-- && (rc == OPAL_HARDWARE
-                                      || rc == OPAL_INTERNAL_ERROR))
-                       msleep(10);
-               else if (rc != OPAL_BUSY && rc != OPAL_BUSY_EVENT)
-                       break;
+               } else if (rc == OPAL_BUSY) {
+                       msleep(OPAL_BUSY_DELAY_MS);
+               } else if (rc == OPAL_HARDWARE || rc == OPAL_INTERNAL_ERROR) {
+                       if (retries--) {
+                               msleep(10); /* Wait 10ms before retry */
+                               rc = OPAL_BUSY; /* go around again */
+                       }
+               }
        }
 
        return rc == OPAL_SUCCESS ? 0 : -EIO;