From fcbd30d09ba05389cb40cc1769b565df62aead35 Mon Sep 17 00:00:00 2001
From: Dejin Zheng <zhengdejin5@gmail.com>
Date: Mon, 23 Mar 2020 23:05:57 +0800
Subject: [PATCH] net: phy: introduce phy_read_poll_timeout macro
Git-commit: fcbd30d09ba05389cb40cc1769b565df62aead35
Patch-mainline: v5.7-rc1
References: git-fixes

[ backport note: additional include of linux/ipoll.h in this patch, which
  had been in commit bd971ff0b739 in upstream -- tiwai ]

it is sometimes necessary to poll a phy register by phy_read()
function until its value satisfies some condition. introduce
phy_read_poll_timeout() macros that do this.

Suggested-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 include/linux/phy.h |   14 ++++++++++++++
 1 file changed, 14 insertions(+)

--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -23,6 +23,7 @@
 #include <linux/timer.h>
 #include <linux/workqueue.h>
 #include <linux/mod_devicetable.h>
+#include <linux/iopoll.h>
 
 #include <linux/atomic.h>
 
@@ -730,6 +731,19 @@ static inline int phy_read(struct phy_de
 	return mdiobus_read(phydev->mdio.bus, phydev->mdio.addr, regnum);
 }
 
+#define phy_read_poll_timeout(phydev, regnum, val, cond, sleep_us, \
+				timeout_us, sleep_before_read) \
+({ \
+	int __ret = read_poll_timeout(phy_read, val, (cond) || val < 0, \
+		sleep_us, timeout_us, sleep_before_read, phydev, regnum); \
+	if (val <  0) \
+		__ret = val; \
+	if (__ret) \
+		phydev_err(phydev, "%s failed: %d\n", __func__, __ret); \
+	__ret; \
+})
+
+
 /**
  * __phy_read - convenience function for reading a given PHY register
  * @phydev: the phy_device struct