regmap: Simplify implementation of the regmap_read_poll_timeout() macro

Simplify the implementation of the macro regmap_read_poll_timeout()
by using the macro read_poll_timeout().
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Link: https://lore.kernel.org/r/20200420134647.9121-2-zhengdejin5@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

include/linux/regmap.h

@@ -17,6 +17,7 @@
 #include <linux/err.h>
 #include <linux/bug.h>
 #include <linux/lockdep.h>
+#include <linux/iopoll.h>
 
 struct module;
 struct clk;
@@ -130,26 +131,10 @@ struct reg_sequence {
  */
 #define regmap_read_poll_timeout(map, addr, val, cond, sleep_us, timeout_us) \
 ({ \
-	u64 __timeout_us = (timeout_us); \
-	unsigned long __sleep_us = (sleep_us); \
-	ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \
-	int __ret; \
-	might_sleep_if(__sleep_us); \
-	for (;;) { \
-		__ret = regmap_read((map), (addr), &(val)); \
-		if (__ret) \
-			break; \
-		if (cond) \
-			break; \
-		if ((__timeout_us) && \
-		    ktime_compare(ktime_get(), __timeout) > 0) { \
-			__ret = regmap_read((map), (addr), &(val)); \
-			break; \
-		} \
-		if (__sleep_us) \
-			usleep_range((__sleep_us >> 2) + 1, __sleep_us); \
-	} \
-	__ret ?: ((cond) ? 0 : -ETIMEDOUT); \
+	int __ret, __tmp; \
+	__tmp = read_poll_timeout(regmap_read, __ret, __ret || (cond), \
+			sleep_us, timeout_us, false, (map), (addr), &(val)); \
+	__ret ?: __tmp; \
 })
 
 /**