rtc: jz4740: Use readl_poll_timeout

Use readl_poll_timeout() from <iopoll.h> instead of using custom poll
loops.

The timeout settings are different, but that shouldn't be much of a
problem. Instead of polling 10000 times in a close loop, it polls for
one millisecond.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20230129120442.22858-3-paul@crapouillou.net
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Author: pcercuei

drivers/rtc/rtc-jz4740.c

@@ -7,6 +7,7 @@
 
 #include <linux/clk.h>
 #include <linux/io.h>
+#include <linux/iopoll.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of_device.h>
@@ -69,31 +70,24 @@ static inline uint32_t jz4740_rtc_reg_read(struct jz4740_rtc *rtc, size_t reg)
 static int jz4740_rtc_wait_write_ready(struct jz4740_rtc *rtc)
 {
 	uint32_t ctrl;
-	int timeout = 10000;
 
-	do {
-		ctrl = jz4740_rtc_reg_read(rtc, JZ_REG_RTC_CTRL);
-	} while (!(ctrl & JZ_RTC_CTRL_WRDY) && --timeout);
-
-	return timeout ? 0 : -EIO;
+	return readl_poll_timeout(rtc->base + JZ_REG_RTC_CTRL, ctrl,
+				  ctrl & JZ_RTC_CTRL_WRDY, 0, 1000);
 }
 
 static inline int jz4780_rtc_enable_write(struct jz4740_rtc *rtc)
 {
 	uint32_t ctrl;
-	int ret, timeout = 10000;
+	int ret;
 
 	ret = jz4740_rtc_wait_write_ready(rtc);
 	if (ret != 0)
 		return ret;
 
 	writel(JZ_RTC_WENR_MAGIC, rtc->base + JZ_REG_RTC_WENR);
 
-	do {
-		ctrl = readl(rtc->base + JZ_REG_RTC_WENR);
-	} while (!(ctrl & JZ_RTC_WENR_WEN) && --timeout);
-
-	return timeout ? 0 : -EIO;
+	return readl_poll_timeout(rtc->base + JZ_REG_RTC_WENR, ctrl,
+				  ctrl & JZ_RTC_WENR_WEN, 0, 1000);
 }
 
 static inline int jz4740_rtc_reg_write(struct jz4740_rtc *rtc, size_t reg,