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authorSergei Shtylyov <sergei.shtylyov@cogentembedded.com>2017-12-04 13:35:05 +0100
committerDavid S. Miller <davem@davemloft.net>2017-12-05 12:51:19 -0500
commitbafbdd527d569c8200521f2f7579f65a044271be (patch)
tree51db9962c079c2ca76a5e9f6d3cb2dc222999c37 /drivers
parent62b32379fd124fea521484ba7e220d8a449f0b59 (diff)
phylib: Add device reset GPIO support
The PHY devices sometimes do have their reset signal (maybe even power supply?) tied to some GPIO and sometimes it also does happen that a boot loader does not leave it deasserted. So far this issue has been attacked from (as I believe) a wrong angle: by teaching the MAC driver to manipulate the GPIO in question; that solution, when applied to the device trees, led to adding the PHY reset GPIO properties to the MAC device node, with one exception: Cadence MACB driver which could handle the "reset-gpios" prop in a PHY device subnode. I believe that the correct approach is to teach the 'phylib' to get the MDIO device reset GPIO from the device tree node corresponding to this device -- which this patch is doing... Note that I had to modify the AT803x PHY driver as it would stop working otherwise -- it made use of the reset GPIO for its own purposes... Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Acked-by: Rob Herring <robh@kernel.org> [geert: Propagate actual errors from fwnode_get_named_gpiod()] [geert: Avoid destroying initial setup] [geert: Consolidate GPIO descriptor acquiring code] Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Richard Leitner <richard.leitner@skidata.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/net/phy/at803x.c18
-rw-r--r--drivers/net/phy/mdio_bus.c21
-rw-r--r--drivers/net/phy/mdio_device.c25
-rw-r--r--drivers/net/phy/phy_device.c32
4 files changed, 77 insertions, 19 deletions
diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
index de7dd6566df7..29da7a3c7a37 100644
--- a/drivers/net/phy/at803x.c
+++ b/drivers/net/phy/at803x.c
@@ -71,7 +71,6 @@ MODULE_LICENSE("GPL");
struct at803x_priv {
bool phy_reset:1;
- struct gpio_desc *gpiod_reset;
};
struct at803x_context {
@@ -254,22 +253,11 @@ static int at803x_probe(struct phy_device *phydev)
{
struct device *dev = &phydev->mdio.dev;
struct at803x_priv *priv;
- struct gpio_desc *gpiod_reset;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
- if (phydev->drv->phy_id != ATH8030_PHY_ID)
- goto does_not_require_reset_workaround;
-
- gpiod_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
- if (IS_ERR(gpiod_reset))
- return PTR_ERR(gpiod_reset);
-
- priv->gpiod_reset = gpiod_reset;
-
-does_not_require_reset_workaround:
phydev->priv = priv;
return 0;
@@ -343,14 +331,14 @@ static void at803x_link_change_notify(struct phy_device *phydev)
* cannot recover from by software.
*/
if (phydev->state == PHY_NOLINK) {
- if (priv->gpiod_reset && !priv->phy_reset) {
+ if (phydev->mdio.reset && !priv->phy_reset) {
struct at803x_context context;
at803x_context_save(phydev, &context);
- gpiod_set_value(priv->gpiod_reset, 1);
+ phy_device_reset(phydev, 1);
msleep(1);
- gpiod_set_value(priv->gpiod_reset, 0);
+ phy_device_reset(phydev, 0);
msleep(1);
at803x_context_restore(phydev, &context);
diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index 2df7b62c1a36..8f8b7747c54b 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -38,6 +38,7 @@
#include <linux/phy.h>
#include <linux/io.h>
#include <linux/uaccess.h>
+#include <linux/gpio/consumer.h>
#include <asm/irq.h>
@@ -48,9 +49,26 @@
int mdiobus_register_device(struct mdio_device *mdiodev)
{
+ struct gpio_desc *gpiod = NULL;
+
if (mdiodev->bus->mdio_map[mdiodev->addr])
return -EBUSY;
+ /* Deassert the optional reset signal */
+ if (mdiodev->dev.of_node)
+ gpiod = fwnode_get_named_gpiod(&mdiodev->dev.of_node->fwnode,
+ "reset-gpios", 0, GPIOD_OUT_LOW,
+ "PHY reset");
+ if (PTR_ERR(gpiod) == -ENOENT)
+ gpiod = NULL;
+ else if (IS_ERR(gpiod))
+ return PTR_ERR(gpiod);
+
+ mdiodev->reset = gpiod;
+
+ /* Assert the reset signal again */
+ mdio_device_reset(mdiodev, 1);
+
mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev;
return 0;
@@ -420,6 +438,9 @@ void mdiobus_unregister(struct mii_bus *bus)
if (!mdiodev)
continue;
+ if (mdiodev->reset)
+ gpiod_put(mdiodev->reset);
+
mdiodev->device_remove(mdiodev);
mdiodev->device_free(mdiodev);
}
diff --git a/drivers/net/phy/mdio_device.c b/drivers/net/phy/mdio_device.c
index e24f28924af8..75d97dd9fb28 100644
--- a/drivers/net/phy/mdio_device.c
+++ b/drivers/net/phy/mdio_device.c
@@ -12,6 +12,8 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/errno.h>
+#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
@@ -114,6 +116,13 @@ void mdio_device_remove(struct mdio_device *mdiodev)
}
EXPORT_SYMBOL(mdio_device_remove);
+void mdio_device_reset(struct mdio_device *mdiodev, int value)
+{
+ if (mdiodev->reset)
+ gpiod_set_value(mdiodev->reset, value);
+}
+EXPORT_SYMBOL(mdio_device_reset);
+
/**
* mdio_probe - probe an MDIO device
* @dev: device to probe
@@ -128,8 +137,16 @@ static int mdio_probe(struct device *dev)
struct mdio_driver *mdiodrv = to_mdio_driver(drv);
int err = 0;
- if (mdiodrv->probe)
+ if (mdiodrv->probe) {
+ /* Deassert the reset signal */
+ mdio_device_reset(mdiodev, 0);
+
err = mdiodrv->probe(mdiodev);
+ if (err) {
+ /* Assert the reset signal */
+ mdio_device_reset(mdiodev, 1);
+ }
+ }
return err;
}
@@ -140,9 +157,13 @@ static int mdio_remove(struct device *dev)
struct device_driver *drv = mdiodev->dev.driver;
struct mdio_driver *mdiodrv = to_mdio_driver(drv);
- if (mdiodrv->remove)
+ if (mdiodrv->remove) {
mdiodrv->remove(mdiodev);
+ /* Assert the reset signal */
+ mdio_device_reset(mdiodev, 1);
+ }
+
return 0;
}
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 8154fb706751..1de5e242b8b4 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -632,6 +632,9 @@ 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) {
@@ -650,6 +653,9 @@ 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;
}
@@ -666,6 +672,10 @@ EXPORT_SYMBOL(phy_device_register);
void phy_device_remove(struct phy_device *phydev)
{
device_del(&phydev->mdio.dev);
+
+ /* Assert the reset signal */
+ phy_device_reset(phydev, 1);
+
mdiobus_unregister_device(&phydev->mdio);
}
EXPORT_SYMBOL(phy_device_remove);
@@ -849,6 +859,9 @@ int phy_init_hw(struct phy_device *phydev)
{
int ret = 0;
+ /* Deassert the reset signal */
+ phy_device_reset(phydev, 0);
+
if (!phydev->drv || !phydev->drv->config_init)
return 0;
@@ -1126,6 +1139,9 @@ void phy_detach(struct phy_device *phydev)
put_device(&phydev->mdio.dev);
if (ndev_owner != bus->owner)
module_put(bus->owner);
+
+ /* Assert the reset signal */
+ phy_device_reset(phydev, 1);
}
EXPORT_SYMBOL(phy_detach);
@@ -1811,8 +1827,16 @@ static int phy_probe(struct device *dev)
/* Set the state to READY by default */
phydev->state = PHY_READY;
- if (phydev->drv->probe)
+ if (phydev->drv->probe) {
+ /* Deassert the reset signal */
+ phy_device_reset(phydev, 0);
+
err = phydev->drv->probe(phydev);
+ if (err) {
+ /* Assert the reset signal */
+ phy_device_reset(phydev, 1);
+ }
+ }
mutex_unlock(&phydev->lock);
@@ -1829,8 +1853,12 @@ static int phy_remove(struct device *dev)
phydev->state = PHY_DOWN;
mutex_unlock(&phydev->lock);
- if (phydev->drv && phydev->drv->remove)
+ if (phydev->drv && phydev->drv->remove) {
phydev->drv->remove(phydev);
+
+ /* Assert the reset signal */
+ phy_device_reset(phydev, 1);
+ }
phydev->drv = NULL;
return 0;