From: Jagan Teki <jagan@amarulasolutions.com>
Date: Sat, 2 May 2020 07:15:02 +0000 (+0530)
Subject: iopoll: Add dealy to read poll
X-Git-Tag: v2020.07-rc2~4^2~4
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c094e219a8614b3da275ad696cdfefbb9f2c453d;p=thirdparty%2Fu-boot.git

iopoll: Add dealy to read poll

Some drivers and other bsp code not only poll the
register with timeout but also required to delay
on each transaction.

This patch add that requirement by adding sleep_us
variable so-that read_poll_timeout now support
delay as well.

This change is referenced from Linux from below commit:
commit <5f5323a14cad19323060a8cbf9d96f2280a462dd> ("iopoll:
introduce read_poll_timeout macro")

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
---

diff --git a/include/linux/iopoll.h b/include/linux/iopoll.h
index 51966d83da9..76d2f951c15 100644
--- a/include/linux/iopoll.h
+++ b/include/linux/iopoll.h
@@ -6,6 +6,7 @@
 #ifndef _LINUX_IOPOLL_H
 #define _LINUX_IOPOLL_H
 
+#include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/io.h>
 #include <time.h>
@@ -16,6 +17,7 @@
  * @addr: Address to poll
  * @val: Variable to read the value into
  * @cond: Break condition (usually involving @val)
+ * @sleep_us: Maximum time to sleep in us
  * @timeout_us: Timeout in us, 0 means never timeout
  *
  * Returns 0 on success and -ETIMEDOUT upon a timeout. In either
@@ -24,7 +26,7 @@
  * When available, you'll probably want to use one of the specialized
  * macros defined below rather than this macro directly.
  */
-#define read_poll_timeout(op, addr, val, cond, timeout_us)	\
+#define read_poll_timeout(op, addr, val, cond, sleep_us, timeout_us)	\
 ({ \
 	unsigned long timeout = timer_get_us() + timeout_us; \
 	for (;;) { \
@@ -35,12 +37,14 @@
 			(val) = op(addr); \
 			break; \
 		} \
+		if (sleep_us) \
+			udelay(sleep_us); \
 	} \
 	(cond) ? 0 : -ETIMEDOUT; \
 })
 
 #define readx_poll_timeout(op, addr, val, cond, timeout_us) \
-	read_poll_timeout(op, addr, val, cond, timeout_us)
+	read_poll_timeout(op, addr, val, cond, false, timeout_us)
 
 #define readb_poll_timeout(addr, val, cond, timeout_us) \
 	readx_poll_timeout(readb, addr, val, cond, timeout_us)