[PATCH v2 1/1] net: phylink: add phylink_set_mac_pm() helper

[PATCH v2 1/1] net: phylink: add phylink_set_mac_pm() helper

[Shenwei Wang]

The recent commit

'commit 47ac7b2f6a1f ("net: phy: Warn about incorrect
mdio_bus_phy_resume() state")'

requires the MAC driver explicitly tell the phy driver who is
managing the PM, otherwise you will see warning during resume
stage.

Add a helper to let the MAC driver has a way to tell the PHY
driver it will manage the PM.

Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com>
---
 Changes in v2:
  - add the API description
  - remove the unneccesary ASSERT_RTNL();

 drivers/net/phy/phylink.c | 17 +++++++++++++++++
 include/linux/phylink.h   |  1 +
 2 files changed, 18 insertions(+)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index e9d62f9598f9..525cf07d5da6 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -1722,6 +1722,23 @@ void phylink_stop(struct phylink *pl)
 }
 EXPORT_SYMBOL_GPL(phylink_stop);

+/**
+ * phylink_set_mac_pm() - set phydev->mac_managed_pm to true
+ * @pl: a pointer to a &struct phylink returned from phylink_create()
+ *
+ * Set the phydev->mac_managed_pm, which is under the phylink instance
+ * specified by @pl, to true. This is to indicate that the MAC driver is
+ * responsible for PHY PM.
+ *
+ * The function can be called in the net_device_ops ndo_open() method.
+ */
+void phylink_set_mac_pm(struct phylink *pl)
+{
+	if (pl->phydev)
+		pl->phydev->mac_managed_pm = true;
+}
+EXPORT_SYMBOL_GPL(phylink_set_mac_pm);
+
 /**
  * phylink_suspend() - handle a network device suspend event
  * @pl: a pointer to a &struct phylink returned from phylink_create()
diff --git a/include/linux/phylink.h b/include/linux/phylink.h
index 6d06896fc20d..cfcc680462b9 100644
--- a/include/linux/phylink.h
+++ b/include/linux/phylink.h
@@ -540,6 +540,7 @@ void phylink_mac_change(struct phylink *, bool up);

 void phylink_start(struct phylink *);
 void phylink_stop(struct phylink *);
+void phylink_set_mac_pm(struct phylink *pl);

 void phylink_suspend(struct phylink *pl, bool mac_wol);
 void phylink_resume(struct phylink *pl);
--
2.34.1

Re: [PATCH v2 1/1] net: phylink: add phylink_set_mac_pm() helper

[Russell King (Oracle)]

On Fri, Oct 07, 2022 at 09:41:11AM -0500, Shenwei Wang wrote:
> +/**
> + * phylink_set_mac_pm() - set phydev->mac_managed_pm to true
> + * @pl: a pointer to a &struct phylink returned from phylink_create()
> + *
> + * Set the phydev->mac_managed_pm, which is under the phylink instance
> + * specified by @pl, to true. This is to indicate that the MAC driver is
> + * responsible for PHY PM.
> + *
> + * The function can be called in the net_device_ops ndo_open() method.

I think this needs to be a bit clearer - a driver author may well ask
"before or after the PHY is connected?" and this really ought to state
this detail.

Otherwise, the patch is fine.

Thanks.

-- 
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