[PATCH/RFC] net: phy: device: Don't deassert the reset when register and probe
From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Date: 2018-11-27 12:18:20
Also in:
linux-devicetree, linux-renesas-soc
Subsystem:
ethernet phy library, networking drivers, the rest · Maintainers:
Andrew Lunn, Heiner Kallweit, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Some PHY device needs edge signal of the reset, but the previous code
is impossible to achieve it like following:
1) Kernel boots by using initramfs.
--> No open the nic, so the provious code deasserts the reset by
phy_device_register() and phy_probe().
2) Kernel enters the suspend.
--> So, keep the reset signal as deassert.
--> On R-Car Salvator-XS board, unfortunately, the board power is
turned off.
3) Kernel returns from suspend.
4) ifconfig eth0 up
--> Then, since edge signal of the reset doesn't happen,
it cannot link up.
5) ifconfig eth0 down
6) ifconfig eth0 up
--> In this case, it can link up.
This patch is possible to break if ->probe() in a phy driver will
access the PHY. But, I believe ->config_init() only initializes
the PHY. However, I think this patch should be RFC at first.
Reported-by: Hiromitsu Yamasaki <redacted>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
---
drivers/net/phy/phy_device.c | 22 +---------------------
1 file changed, 1 insertion(+), 21 deletions(-)
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index e06613f..e01a752 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c@@ -802,16 +802,6 @@ int phy_device_register(struct phy_device *phydev) if (err) return err; - /* Deassert the reset signal */ - phy_device_reset(phydev, 0); - - /* Run all of the fixups for this PHY */ - err = phy_scan_fixups(phydev); - if (err) { - pr_err("PHY %d failed to initialize\n", phydev->mdio.addr); - goto out; - } - err = device_add(&phydev->mdio.dev); if (err) { pr_err("PHY %d failed to add\n", phydev->mdio.addr);
@@ -821,8 +811,6 @@ int phy_device_register(struct phy_device *phydev) return 0; out: - /* Assert the reset signal */ - phy_device_reset(phydev, 1); mdiobus_unregister_device(&phydev->mdio); return err;
@@ -2202,16 +2190,8 @@ static int phy_probe(struct device *dev) /* Set the state to READY by default */ phydev->state = PHY_READY; - if (phydev->drv->probe) { - /* Deassert the reset signal */ - phy_device_reset(phydev, 0); - + if (phydev->drv->probe) err = phydev->drv->probe(phydev); - if (err) { - /* Assert the reset signal */ - phy_device_reset(phydev, 1); - } - } mutex_unlock(&phydev->lock);
--
1.9.1