Merge branch 'introduce-read_poll_timeout'

Dejin Zheng says:

====================
introduce read_poll_timeout

This patch sets is introduce read_poll_timeout macro, it is an extension
of readx_poll_timeout macro. the accessor function op just supports only
one parameter in the readx_poll_timeout macro, but this macro can
supports multiple variable parameters for it. so functions like
phy_read(struct phy_device *phydev, u32 regnum) and
phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum) can
use this poll timeout framework.

the first patch introduce read_poll_timeout macro, and the second patch
redefined readx_poll_timeout macro by read_poll_timeout(), and the other
patches are examples using read_poll_timeout macro.

v6 -> v7:
- add a parameter to supports that it can sleep some time
before read operation in read_poll_timeout macro.
- add prefix with double underscores for some variable to avoid
any variable re-declaration or shadowing in patch 3 and patch
7.
v5 -> v6:
- add some check to keep the code more similar in patch 8
v4 -> v5:
- add some msleep() before call phy_read_mmd_poll_timeout() to
keep the code more similar in patch 6 and patch 9.
- add a patch of drop by v4, it can add msleep before call
phy_read_poll_timeout() to keep the code more similar.
v3 -> v4:
- add 3 examples of using new functions.
- deal with precedence issues for parameter cond.
- drop a patch about phy_poll_reset() function.
v2 -> v3:
- modify the parameter order of newly added functions.
phy_read_mmd_poll_timeout(val, cond, sleep_us, timeout_us, \
phydev, devaddr, regnum)
||
\/
phy_read_mmd_poll_timeout(phydev, devaddr regnum, val, cond, \
sleep_us, timeout_us)

phy_read_poll_timeout(val, cond, sleep_us, timeout_us, \
phydev, regnum)
||
\/
phy_read_poll_timeout(phydev, regnum, val, cond, sleep_us, \
timeout_us)
v1 -> v2:
- passed a phydev, device address and a reg to replace args...
parameter in phy_read_mmd_poll_timeout() by Andrew Lunn 's
suggestion in patch 3. Andrew Lunn <[e-mail]>, Thanks
very much for your help!
- also in patch 3, handle phy_read_mmd return an error(the return
value < 0) in phy_read_mmd_poll_timeout(). Thanks Andrew
again.
- in patch 6, pass a phydev and a reg to replace args...
parameter in phy_read_poll_timeout(), and also handle the
phy_read() function's return error.
====================

Signed-off-by: David S. Miller <[e-mail]>

drivers/net/phy/aquantia_main.c

···
  */
 static int aqr107_wait_reset_complete(struct phy_device *phydev)
 {
-	int val, retries = 100;
+	int val;
 
-	do {
-		val = phy_read_mmd(phydev, MDIO_MMD_VEND1, VEND1_GLOBAL_FW_ID);
-		if (val < 0)
-			return val;
-		msleep(20);
-	} while (!val && --retries);
-
-	return val ? 0 : -ETIMEDOUT;
+	return phy_read_mmd_poll_timeout(phydev, MDIO_MMD_VEND1,
+					 VEND1_GLOBAL_FW_ID, val, val != 0,
+					 20000, 2000000, false);
 }
 
 static void aqr107_chip_info(struct phy_device *phydev)

drivers/net/phy/bcm84881.c

···
 
 static int bcm84881_wait_init(struct phy_device *phydev)
 {
-	unsigned int tries = 20;
-	int ret, val;
+	int val;
 
-	do {
-		val = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_CTRL1);
-		if (val < 0) {
-			ret = val;
-			break;
-		}
-		if (!(val & MDIO_CTRL1_RESET)) {
-			ret = 0;
-			break;
-		}
-		if (!--tries) {
-			ret = -ETIMEDOUT;
-			break;
-		}
-		msleep(100);
-	} while (1);
-
-	if (ret)
-		phydev_err(phydev, "%s failed: %d\n", __func__, ret);
-
-	return ret;
+	return phy_read_mmd_poll_timeout(phydev, MDIO_MMD_PMAPMD, MDIO_CTRL1,
+					 val, !(val & MDIO_CTRL1_RESET),
+					 100000, 2000000, false);
 }
 
 static int bcm84881_config_init(struct phy_device *phydev)

drivers/net/phy/marvell10g.c

···
 
 static int mv3310_reset(struct phy_device *phydev, u32 unit)
 {
-	int retries, val, err;
+	int val, err;
 
 	err = phy_modify_mmd(phydev, MDIO_MMD_PCS, unit + MDIO_CTRL1,
 			     MDIO_CTRL1_RESET, MDIO_CTRL1_RESET);
 	if (err < 0)
 		return err;
 
-	retries = 20;
-	do {
-		msleep(5);
-		val = phy_read_mmd(phydev, MDIO_MMD_PCS, unit + MDIO_CTRL1);
-		if (val < 0)
-			return val;
-	} while (val & MDIO_CTRL1_RESET && --retries);
-
-	return val & MDIO_CTRL1_RESET ? -ETIMEDOUT : 0;
+	return phy_read_mmd_poll_timeout(phydev, MDIO_MMD_PCS,
+					 unit + MDIO_CTRL1, val,
+					 !(val & MDIO_CTRL1_RESET),
+					 5000, 100000, true);
 }
 
 static int mv3310_get_edpd(struct phy_device *phydev, u16 *edpd)

drivers/net/phy/nxp-tja11xx.c

···
 
 static int tja11xx_check(struct phy_device *phydev, u8 reg, u16 mask, u16 set)
 {
-	int i, ret;
+	int val;
 
-	for (i = 0; i < 200; i++) {
-		ret = phy_read(phydev, reg);
-		if (ret < 0)
-			return ret;
-
-		if ((ret & mask) == set)
-			return 0;
-
-		usleep_range(100, 150);
-	}
-
-	return -ETIMEDOUT;
+	return phy_read_poll_timeout(phydev, reg, val, (val & mask) == set,
+				     150, 30000, false);
 }
 
 static int phy_modify_check(struct phy_device *phydev, u8 reg,

drivers/net/phy/phy_device.c

···
 static int phy_poll_reset(struct phy_device *phydev)
 {
 	/* Poll until the reset bit clears (50ms per retry == 0.6 sec) */
-	unsigned int retries = 12;
-	int ret;
+	int ret, val;
 
-	do {
-		msleep(50);
-		ret = phy_read(phydev, MII_BMCR);
-		if (ret < 0)
-			return ret;
-	} while (ret & BMCR_RESET && --retries);
-	if (ret & BMCR_RESET)
-		return -ETIMEDOUT;
-
+	ret = phy_read_poll_timeout(phydev, MII_BMCR, val, !(val & BMCR_RESET),
+				    50000, 600000, true);
+	if (ret)
+		return ret;
 	/* Some chips (smsc911x) may still need up to another 1ms after the
 	 * BMCR_RESET bit is cleared before they are usable.
 	 */

drivers/net/phy/smsc.c

···
 	int err = genphy_read_status(phydev);
 
 	if (!phydev->link && priv->energy_enable) {
-		int i;
-
 		/* Disable EDPD to wake up PHY */
 		int rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
 		if (rc < 0)
···
 			return rc;
 
 		/* Wait max 640 ms to detect energy */
-		for (i = 0; i < 64; i++) {
-			/* Sleep to allow link test pulses to be sent */
-			msleep(10);
-			rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
-			if (rc < 0)
-				return rc;
-			if (rc & MII_LAN83C185_ENERGYON)
-				break;
-		}
+		phy_read_poll_timeout(phydev, MII_LAN83C185_CTRL_STATUS, rc,
+				      rc & MII_LAN83C185_ENERGYON, 10000,
+				      640000, true);
+		if (rc < 0)
+			return rc;
 
 		/* Re-enable EDPD */
 		rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);

include/linux/iopoll.h

···
 #include <linux/io.h>
 
 /**
+ * read_poll_timeout - Periodically poll an address until a condition is
+ *			met or a timeout occurs
+ * @op: accessor function (takes @args as its arguments)
+ * @val: Variable to read the value into
+ * @cond: Break condition (usually involving @val)
+ * @sleep_us: Maximum time to sleep between reads in us (0
+ *            tight-loops).  Should be less than ~20ms since usleep_range
+ *            is used (see Documentation/timers/timers-howto.rst).
+ * @timeout_us: Timeout in us, 0 means never timeout
+ * @sleep_before_read: if it is true, sleep @sleep_us before read.
+ * @args: arguments for @op poll
+ *
+ * Returns 0 on success and -ETIMEDOUT upon a timeout. In either
+ * case, the last read value at @args is stored in @val. Must not
+ * be called from atomic context if sleep_us or timeout_us are used.
+ *
+ * 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, val, cond, sleep_us, timeout_us, \
+				sleep_before_read, args...) \
+({ \
+	u64 __timeout_us = (timeout_us); \
+	unsigned long __sleep_us = (sleep_us); \
+	ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \
+	might_sleep_if((__sleep_us) != 0); \
+	if (sleep_before_read && __sleep_us) \
+		usleep_range((__sleep_us >> 2) + 1, __sleep_us); \
+	for (;;) { \
+		(val) = op(args); \
+		if (cond) \
+			break; \
+		if (__timeout_us && \
+		    ktime_compare(ktime_get(), __timeout) > 0) { \
+			(val) = op(args); \
+			break; \
+		} \
+		if (__sleep_us) \
+			usleep_range((__sleep_us >> 2) + 1, __sleep_us); \
+	} \
+	(cond) ? 0 : -ETIMEDOUT; \
+})
+
+/**
  * readx_poll_timeout - Periodically poll an address until a condition is met or a timeout occurs
  * @op: accessor function (takes @addr as its only argument)
  * @addr: Address to poll
···
  * macros defined below rather than this macro directly.
  */
 #define readx_poll_timeout(op, 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); \
-	might_sleep_if((__sleep_us) != 0); \
-	for (;;) { \
-		(val) = op(addr); \
-		if (cond) \
-			break; \
-		if (__timeout_us && \
-		    ktime_compare(ktime_get(), __timeout) > 0) { \
-			(val) = op(addr); \
-			break; \
-		} \
-		if (__sleep_us) \
-			usleep_range((__sleep_us >> 2) + 1, __sleep_us); \
-	} \
-	(cond) ? 0 : -ETIMEDOUT; \
-})
+	read_poll_timeout(op, val, cond, sleep_us, timeout_us, false, addr)
 
 /**
  * readx_poll_timeout_atomic - Periodically poll an address until a condition is met or a timeout occurs

include/linux/phy.h

···
 #include <linux/mod_devicetable.h>
 #include <linux/u64_stats_sync.h>
 #include <linux/irqreturn.h>
+#include <linux/iopoll.h>
 
 #include <linux/atomic.h>
 
···
 	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
···
  * Same rules as for phy_read();
  */
 int phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum);
+
+#define phy_read_mmd_poll_timeout(phydev, devaddr, regnum, val, cond, \
+				  sleep_us, timeout_us, sleep_before_read) \
+({ \
+	int __ret = read_poll_timeout(phy_read_mmd, val, (cond) || val < 0, \
+				  sleep_us, timeout_us, sleep_before_read, \
+				  phydev, devaddr, regnum); \
+	if (val <  0) \
+		__ret = val; \
+	if (__ret) \
+		phydev_err(phydev, "%s failed: %d\n", __func__, __ret); \
+	__ret; \
+})
 
 /**
  * __phy_read_mmd - Convenience function for reading a register