wait_bit: add 8/16/32 BE/LE versions of wait_for_bit

Add 8/16/32 bits and BE/LE versions of wait_for_bit.
This is needed for reading registers that are not aligned to 32 bits, and for
Big Endian platforms.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>

diff --git a/include/wait_bit.h b/include/wait_bit.h
index 06ad43a122d69f5f58830ed387183e0f213d96df..e8acfa577666005301efba3b383fddc61c2c4c2d 100644 (file)
--- a/include/wait_bit.h
+++ b/include/wait_bit.h
@@ -69,5 +69,70 @@ static inline int wait_for_bit(const char *prefix, const u32 *reg,
        return -ETIMEDOUT;
 }
 
+/**
+ * wait_for_bit_x()    waits for bit set/cleared in register
+ *
+ * Function polls register waiting for specific bit(s) change
+ * (either 0->1 or 1->0). It can fail under two conditions:
+ * - Timeout
+ * - User interaction (CTRL-C)
+ * Function succeeds only if all bits of masked register are set/cleared
+ * (depending on set option).
+ *
+ * @param reg          Register that will be read (using read_x())
+ * @param mask         Bit(s) of register that must be active
+ * @param set          Selects wait condition (bit set or clear)
+ * @param timeout_ms   Timeout (in milliseconds)
+ * @param breakable    Enables CTRL-C interruption
+ * @return             0 on success, -ETIMEDOUT or -EINTR on failure
+ */
+
+#define BUILD_WAIT_FOR_BIT(sfx, type, read)                            \
+                                                                       \
+static inline int wait_for_bit_##sfx(const void *reg,                  \
+                                    const type mask,                   \
+                                    const bool set,                    \
+                                    const unsigned int timeout_ms,     \
+                                    const bool breakable)              \
+{                                                                      \
+       type val;                                                       \
+       unsigned long start = get_timer(0);                             \
+                                                                       \
+       while (1) {                                                     \
+               val = read(reg);                                        \
+                                                                       \
+               if (!set)                                               \
+                       val = ~val;                                     \
+                                                                       \
+               if ((val & mask) == mask)                               \
+                       return 0;                                       \
+                                                                       \
+               if (get_timer(start) > timeout_ms)                      \
+                       break;                                          \
+                                                                       \
+               if (breakable && ctrlc()) {                             \
+                       puts("Abort\n");                                \
+                       return -EINTR;                                  \
+               }                                                       \
+                                                                       \
+               udelay(1);                                              \
+               WATCHDOG_RESET();                                       \
+       }                                                               \
+                                                                       \
+       debug("%s: Timeout (reg=%p mask=%x wait_set=%i)\n", __func__,   \
+             reg, mask, set);                                          \
+                                                                       \
+       return -ETIMEDOUT;                                              \
+}
+
+BUILD_WAIT_FOR_BIT(8, u8, readb)
+BUILD_WAIT_FOR_BIT(le16, u16, readw)
+#ifdef readw_be
+BUILD_WAIT_FOR_BIT(be16, u16, readw_be)
+#endif
+BUILD_WAIT_FOR_BIT(le32, u32, readl)
+#ifdef readl_be
+BUILD_WAIT_FOR_BIT(be32, u32, readl_be)
+#endif
 
 #endif