ath79: backport phy reset-controller patches

The Siemens WS-AP3610 asserts reset to the ethernet PHY with the
reset-register. Backport the necessary patches to de-assert reset
when probing the PHY.

These patches can be dropped when using kernel 5.4.

Signed-off-by: David Bauer <mail@david-bauer.net>

diff --git a/target/linux/ath79/patches-4.19/700-net-phy-add-reset-controller-support.patch b/target/linux/ath79/patches-4.19/700-net-phy-add-reset-controller-support.patch
new file mode 100644 (file)
index 0000000..9f96390
--- /dev/null
+++ b/target/linux/ath79/patches-4.19/700-net-phy-add-reset-controller-support.patch
@@ -0,0 +1,107 @@
+From 71dd6c0dff51b5f1fef2e9dfa6f6a948aac975f3 Mon Sep 17 00:00:00 2001
+From: David Bauer <mail@david-bauer.net>
+Date: Wed, 17 Apr 2019 23:59:21 +0200
+Subject: [PATCH] net: phy: add support for reset-controller
+
+This commit adds support for PHY reset pins handled by a reset controller.
+
+Signed-off-by: David Bauer <mail@david-bauer.net>
+Reviewed-by: Andrew Lunn <andrew@lunn.ch>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/phy/mdio_bus.c    | 27 +++++++++++++++++++++++++--
+ drivers/net/phy/mdio_device.c | 13 +++++++++++--
+ include/linux/mdio.h          |  1 +
+ 3 files changed, 37 insertions(+), 4 deletions(-)
+
+--- a/drivers/net/phy/mdio_bus.c
++++ b/drivers/net/phy/mdio_bus.c
+@@ -29,6 +29,7 @@
+ #include <linux/of_gpio.h>
+ #include <linux/netdevice.h>
+ #include <linux/etherdevice.h>
++#include <linux/reset.h>
+ #include <linux/skbuff.h>
+ #include <linux/spinlock.h>
+ #include <linux/mm.h>
+@@ -65,8 +66,23 @@ static int mdiobus_register_gpiod(struct
+ 
+       mdiodev->reset = gpiod;
+ 
+-      /* Assert the reset signal again */
+-      mdio_device_reset(mdiodev, 1);
++      return 0;
++}
++
++static int mdiobus_register_reset(struct mdio_device *mdiodev)
++{
++      struct reset_control *reset = NULL;
++
++      if (mdiodev->dev.of_node)
++              reset = devm_reset_control_get_exclusive(&mdiodev->dev,
++                                                       "phy");
++      if (PTR_ERR(reset) == -ENOENT ||
++          PTR_ERR(reset) == -ENOTSUPP)
++              reset = NULL;
++      else if (IS_ERR(reset))
++              return PTR_ERR(reset);
++
++      mdiodev->reset_ctrl = reset;
+ 
+       return 0;
+ }
+@@ -82,6 +98,13 @@ int mdiobus_register_device(struct mdio_
+               err = mdiobus_register_gpiod(mdiodev);
+               if (err)
+                       return err;
++
++              err = mdiobus_register_reset(mdiodev);
++              if (err)
++                      return err;
++
++              /* Assert the reset signal */
++              mdio_device_reset(mdiodev, 1);
+       }
+ 
+       mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev;
+--- a/drivers/net/phy/mdio_device.c
++++ b/drivers/net/phy/mdio_device.c
+@@ -21,6 +21,7 @@
+ #include <linux/mii.h>
+ #include <linux/module.h>
+ #include <linux/phy.h>
++#include <linux/reset.h>
+ #include <linux/slab.h>
+ #include <linux/string.h>
+ #include <linux/unistd.h>
+@@ -121,10 +122,18 @@ void mdio_device_reset(struct mdio_devic
+ {
+       unsigned int d;
+ 
+-      if (!mdiodev->reset)
++      if (!mdiodev->reset && !mdiodev->reset_ctrl)
+               return;
+ 
+-      gpiod_set_value(mdiodev->reset, value);
++      if (mdiodev->reset)
++              gpiod_set_value(mdiodev->reset, value);
++
++      if (mdiodev->reset_ctrl) {
++              if (value)
++                      reset_control_assert(mdiodev->reset_ctrl);
++              else
++                      reset_control_deassert(mdiodev->reset_ctrl);
++      }
+ 
+       d = value ? mdiodev->reset_assert_delay : mdiodev->reset_deassert_delay;
+       if (d)
+--- a/include/linux/mdio.h
++++ b/include/linux/mdio.h
+@@ -40,6 +40,7 @@ struct mdio_device {
+       int addr;
+       int flags;
+       struct gpio_desc *reset;
++      struct reset_control *reset_ctrl;
+       unsigned int reset_assert_delay;
+       unsigned int reset_deassert_delay;
+ };

diff --git a/target/linux/ath79/patches-4.19/701-mdio-bus-dont-use-managed-reset-controller.patch b/target/linux/ath79/patches-4.19/701-mdio-bus-dont-use-managed-reset-controller.patch
new file mode 100644 (file)
index 0000000..16e7f20
--- /dev/null
+++ b/target/linux/ath79/patches-4.19/701-mdio-bus-dont-use-managed-reset-controller.patch
@@ -0,0 +1,44 @@
+From 32085f25d7b68404055f3525c780142fc72e543f Mon Sep 17 00:00:00 2001
+From: David Bauer <mail@david-bauer.net>
+Date: Fri, 22 Nov 2019 22:44:51 +0100
+Subject: [PATCH] mdio_bus: don't use managed reset-controller
+
+Geert Uytterhoeven reported that using devm_reset_controller_get leads
+to a WARNING when probing a reset-controlled PHY. This is because the
+device devm_reset_controller_get gets supplied is not actually the
+one being probed.
+
+Acquire an unmanaged reset-control as well as free the reset_control on
+unregister to fix this.
+
+Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
+CC: Andrew Lunn <andrew@lunn.ch>
+Signed-off-by: David Bauer <mail@david-bauer.net>
+Reviewed-by: Andrew Lunn <andrew@lunn.ch>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/phy/mdio_bus.c | 6 ++++--
+ 1 file changed, 4 insertions(+), 2 deletions(-)
+
+--- a/drivers/net/phy/mdio_bus.c
++++ b/drivers/net/phy/mdio_bus.c
+@@ -74,8 +74,8 @@ static int mdiobus_register_reset(struct
+       struct reset_control *reset = NULL;
+ 
+       if (mdiodev->dev.of_node)
+-              reset = devm_reset_control_get_exclusive(&mdiodev->dev,
+-                                                       "phy");
++              reset = of_reset_control_get_exclusive(mdiodev->dev.of_node,
++                                                     "phy");
+       if (PTR_ERR(reset) == -ENOENT ||
+           PTR_ERR(reset) == -ENOTSUPP)
+               reset = NULL;
+@@ -118,6 +118,8 @@ int mdiobus_unregister_device(struct mdi
+       if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)
+               return -EINVAL;
+ 
++      reset_control_put(mdiodev->reset_ctrl);
++
+       mdiodev->bus->mdio_map[mdiodev->addr] = NULL;
+ 
+       return 0;