2023-06-05 15:25:55

by Detlev Casanova

[permalink] [raw]
Subject: net: phy: realtek: Support external PHY clock

Some PHYs can use an external clock that must be enabled before
communicating with them.

Changes since v2:
* Reword documentation commit message

Changes since v1:
* Remove the clock name as it is not guaranteed to be identical across
different PHYs
* Disable/Enable the clock when suspending/resuming




2023-06-05 15:29:29

by Detlev Casanova

[permalink] [raw]
Subject: [PATCH v3 1/3] net: phy: realtek: Add optional external PHY clock

In some cases, the PHY can use an external clock source instead of a
crystal.

Add an optional clock in the phy node to make sure that the clock source
is enabled, if specified, before probing.

Reviewed-by: Florian Fainelli <[email protected]>
Reviewed-by: Andrew Lunn <[email protected]>
Signed-off-by: Detlev Casanova <[email protected]>
---
drivers/net/phy/realtek.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/net/phy/realtek.c b/drivers/net/phy/realtek.c
index 3d99fd6664d7..b13dd0b3c99e 100644
--- a/drivers/net/phy/realtek.c
+++ b/drivers/net/phy/realtek.c
@@ -12,6 +12,7 @@
#include <linux/phy.h>
#include <linux/module.h>
#include <linux/delay.h>
+#include <linux/clk.h>

#define RTL821x_PHYSR 0x11
#define RTL821x_PHYSR_DUPLEX BIT(13)
@@ -80,6 +81,7 @@ struct rtl821x_priv {
u16 phycr1;
u16 phycr2;
bool has_phycr2;
+ struct clk *clk;
};

static int rtl821x_read_page(struct phy_device *phydev)
@@ -103,6 +105,11 @@ static int rtl821x_probe(struct phy_device *phydev)
if (!priv)
return -ENOMEM;

+ priv->clk = devm_clk_get_optional_enabled(dev, NULL);
+ if (IS_ERR(priv->clk))
+ return dev_err_probe(dev, PTR_ERR(priv->clk),
+ "failed to get phy clock\n");
+
ret = phy_read_paged(phydev, 0xa43, RTL8211F_PHYCR1);
if (ret < 0)
return ret;
--
2.39.3


2023-06-05 15:29:37

by Detlev Casanova

[permalink] [raw]
Subject: [PATCH v3 2/3] dt-bindings: net: phy: Document support for external PHY clk

Ethern PHYs can have external an clock that needs to be activated before
communicating with the PHY.

Acked-by: Krzysztof Kozlowski <[email protected]>
Signed-off-by: Detlev Casanova <[email protected]>
---
Documentation/devicetree/bindings/net/ethernet-phy.yaml | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
index 4f574532ee13..c1241c8a3b77 100644
--- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
+++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
@@ -93,6 +93,12 @@ properties:
the turn around line low at end of the control phase of the
MDIO transaction.

+ clocks:
+ maxItems: 1
+ description:
+ External clock connected to the PHY. If not specified it is assumed
+ that the PHY uses a fixed crystal or an internal oscillator.
+
enet-phy-lane-swap:
$ref: /schemas/types.yaml#/definitions/flag
description:
--
2.39.3


2023-06-05 15:30:51

by Detlev Casanova

[permalink] [raw]
Subject: [PATCH v3 3/3] net: phy: realtek: Disable clock on suspend

For PHYs that call rtl821x_probe() where an external clock can be
configured, make sure that the clock is disabled
when ->suspend() is called and enabled on resume.

The PHY_ALWAYS_CALL_SUSPEND is added to ensure that the suspend function
is actually always called.

Reviewed-by: Florian Fainelli <[email protected]>
Signed-off-by: Detlev Casanova <[email protected]>
---
drivers/net/phy/realtek.c | 24 ++++++++++++++++++++++--
1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/drivers/net/phy/realtek.c b/drivers/net/phy/realtek.c
index b13dd0b3c99e..62eac4835def 100644
--- a/drivers/net/phy/realtek.c
+++ b/drivers/net/phy/realtek.c
@@ -426,10 +426,28 @@ static int rtl8211f_config_init(struct phy_device *phydev)
return genphy_soft_reset(phydev);
}

+static int rtl821x_suspend(struct phy_device *phydev)
+{
+ struct rtl821x_priv *priv = phydev->priv;
+ int ret = genphy_suspend(phydev);
+
+ if (ret)
+ return ret;
+
+ if (!phydev->wol_enabled)
+ clk_disable_unprepare(priv->clk);
+
+ return ret;
+}
+
static int rtl821x_resume(struct phy_device *phydev)
{
+ struct rtl821x_priv *priv = phydev->priv;
int ret;

+ if (!phydev->wol_enabled)
+ clk_prepare_enable(priv->clk);
+
ret = genphy_resume(phydev);
if (ret < 0)
return ret;
@@ -934,10 +952,11 @@ static struct phy_driver realtek_drvs[] = {
.read_status = rtlgen_read_status,
.config_intr = &rtl8211f_config_intr,
.handle_interrupt = rtl8211f_handle_interrupt,
- .suspend = genphy_suspend,
+ .suspend = rtl821x_suspend,
.resume = rtl821x_resume,
.read_page = rtl821x_read_page,
.write_page = rtl821x_write_page,
+ .flags = PHY_ALWAYS_CALL_SUSPEND,
}, {
PHY_ID_MATCH_EXACT(RTL_8211FVD_PHYID),
.name = "RTL8211F-VD Gigabit Ethernet",
@@ -946,10 +965,11 @@ static struct phy_driver realtek_drvs[] = {
.read_status = rtlgen_read_status,
.config_intr = &rtl8211f_config_intr,
.handle_interrupt = rtl8211f_handle_interrupt,
- .suspend = genphy_suspend,
+ .suspend = rtl821x_suspend,
.resume = rtl821x_resume,
.read_page = rtl821x_read_page,
.write_page = rtl821x_write_page,
+ .flags = PHY_ALWAYS_CALL_SUSPEND,
}, {
.name = "Generic FE-GE Realtek PHY",
.match_phy_device = rtlgen_match_phy_device,
--
2.39.3


2023-06-05 15:31:31

by Florian Fainelli

[permalink] [raw]
Subject: Re: [PATCH v3 3/3] net: phy: realtek: Disable clock on suspend

On 6/5/23 08:19, Detlev Casanova wrote:
> For PHYs that call rtl821x_probe() where an external clock can be
> configured, make sure that the clock is disabled
> when ->suspend() is called and enabled on resume.
>
> The PHY_ALWAYS_CALL_SUSPEND is added to ensure that the suspend function
> is actually always called.
>
> Reviewed-by: Florian Fainelli <[email protected]>
> Signed-off-by: Detlev Casanova <[email protected]>
> ---
> drivers/net/phy/realtek.c | 24 ++++++++++++++++++++++--
> 1 file changed, 22 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/phy/realtek.c b/drivers/net/phy/realtek.c
> index b13dd0b3c99e..62eac4835def 100644
> --- a/drivers/net/phy/realtek.c
> +++ b/drivers/net/phy/realtek.c
> @@ -426,10 +426,28 @@ static int rtl8211f_config_init(struct phy_device *phydev)
> return genphy_soft_reset(phydev);
> }
>
> +static int rtl821x_suspend(struct phy_device *phydev)
> +{
> + struct rtl821x_priv *priv = phydev->priv;
> + int ret = genphy_suspend(phydev);

Sorry I missed that part, if Wake-on-LAN is enabled you cannot suspend
the PHY as this will typically prevent it from passing received frames
up the MAC where Wake-on-LAN can be done. You need to move
genphy_suspend() into the !phydev->wol_enabled clause.
--
Florian


2023-06-05 22:12:44

by Jakub Kicinski

[permalink] [raw]
Subject: Re: net: phy: realtek: Support external PHY clock

On Mon, 5 Jun 2023 11:19:50 -0400 Detlev Casanova wrote:
> Some PHYs can use an external clock that must be enabled before
> communicating with them.

Please add a [PATCH v4 0/0] prefix to the subject of the cover letter
(or use --cover-letter with git format-patch to generate the template).
Otherwise patchwork doesn't realize this is a cover letter.

2023-06-05 22:33:57

by Jakub Kicinski

[permalink] [raw]
Subject: Re: net: phy: realtek: Support external PHY clock

On Mon, 5 Jun 2023 14:45:01 -0700 Jakub Kicinski wrote:
> On Mon, 5 Jun 2023 11:19:50 -0400 Detlev Casanova wrote:
> > Some PHYs can use an external clock that must be enabled before
> > communicating with them.
>
> Please add a [PATCH v4 0/0] prefix to the subject of the cover letter
> (or use --cover-letter with git format-patch to generate the template).
> Otherwise patchwork doesn't realize this is a cover letter.

And so it didn't realize you already sent a v4...
FWIW we ask people not to repost within 24h, confuses reviewers.