Hello!
On 10/20/2017 9:11 PM, Florian Fainelli wrote:
From: Sergei Shtylyov <sergei.shtylyov@xxxxxxxxxxxxxxxxxx>
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@xxxxxxxxxxxxxxxxxx>
Acked-by: Rob Herring <robh@xxxxxxxxxx>
Acked-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
This is a new patch as far as PHYLIB is concerned, so not quite accurate
No, it is not new. No changes in logic since v2.
anymore. Thanks for picking that up, this looks good, with a few minor
things here and there.
[geert: Propagate actual errors from fwnode_get_named_gpiod()]
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
[...]
diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
index 5f93e6add56394f2..15b4560aeb5de759 100644
--- a/drivers/net/phy/at803x.c
+++ b/drivers/net/phy/at803x.c
You most certainly want to make the conversion of the at803x.c driver as
a separate patch, there is no reason why it should be folded within the
No, it can't be a separate patch, otherwise I would have posted it
separately. We cannot request the same GPIO 2 times.
patch teaching PHYLIB about PHY reset through GPIOs. More on that below.
[...]
@@ -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;
We have lost that bit now, see below.
Hm... I'm still seeing this in net-next.
-
- 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) {
and phydev->drv->phy_id == ATH8030_PHY_ID, the workaround is not
applicable to all PHY devices.
You are clearly looking at an outdated tree -- this check was removed,
This method is populated only for 8030 instead.
[...]
diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c
index 98258583abb0b405..3d044119c032d176 100644
--- a/drivers/of/of_mdio.c
+++ b/drivers/of/of_mdio.c
[...]
@@ -55,10 +56,22 @@ static int of_mdiobus_register_phy(struct mii_bus *mdio,
is_c45 = of_device_is_compatible(child,
"ethernet-phy-ieee802.3-c45");
+ /* Deassert the optional reset signal */
+ gpiod = fwnode_get_named_gpiod(&child->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);
+
if (!is_c45 && !of_get_phy_id(child, &phy_id))
phy = phy_device_create(mdio, addr, phy_id, 0, NULL);
else
phy = get_phy_device(mdio, addr, is_c45);
+
+ /* Assert the reset signal again */
+ gpiod_set_value(gpiod, 1);
You have a phy_device reference now, so why not call phy_device_reset()
directly here?
Symmetry, perhaps? (There was a gpiod_set_value(gpiod, 0) call above it...
[...]
@@ -112,6 +127,14 @@ static int of_mdiobus_register_device(struct mii_bus *mdio,
of_node_get(child);
mdiodev->dev.of_node = child;
+ gpiod = fwnode_get_named_gpiod(&child->fwnode, "reset-gpios", 0,
+ GPIOD_ASIS, "PHY reset");
+ if (PTR_ERR(gpiod) == -ENOENT)
+ gpiod = NULL;
+ else if (IS_ERR(gpiod))
+ return PTR_ERR(gpiod);
+ mdiodev->reset = gpiod;
There is some obvious and non desireable duplication of code between
"pure" mdio_device and phy_device paths here, can you factor this such
that there is a common function storing gpiod into a mdio_device's reset
member in both cases?
Also, there is some asymetry being exposed here, the GPIO descriptor is
acquired from OF specific code, but is released in the generic MDIO
device layer, can we find a way to make that symmetrical?
Finally move of_mdio.c into drivers/net/phy/? ;-)
MBR, Sergei
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