* Re: [PATCH 2/2] dt-bindings: net: adi,adin: document LP termination property
2025-12-16 15:48 [PATCH 1/2] net: phy: adin: enable configuration of the LP Termination Register Osose Itua
@ 2025-12-16 15:50 ` Osose Itua
2025-12-16 17:02 ` [External] : [PATCH 1/2] net: phy: adin: enable configuration of the LP Termination Register ALOK TIWARI
1 sibling, 0 replies; 3+ messages in thread
From: Osose Itua @ 2025-12-16 15:50 UTC (permalink / raw)
To: netdev; +Cc: devicetree, linux-kernel, Michael Hennerich, Jérome Oufella
From 4b4409504fd41c81c7150ae1d88bc0ca755e6ace Mon Sep 17 00:00:00 2001
From: Osose Itua <osose.itua@savoirfairelinux.com>
Date: Mon, 15 Dec 2025 17:59:38 -0500
Subject: [PATCH 2/2] dt-bindings: net: adi,adin: document LP termination
property
Add "adi,low-cmode-impedance" boolean property which, when present,
configures the PHY for the lowest common-mode impedance on the receive
pair for 100BASE-TX operation.
Signed-off-by: Osose Itua <osose.itua@savoirfairelinux.com>
---
Documentation/devicetree/bindings/net/adi,adin.yaml | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/Documentation/devicetree/bindings/net/adi,adin.yaml b/Documentation/devicetree/bindings/net/adi,adin.yaml
index c425a9f1886d..d3c8c5cc4bb1 100644
--- a/Documentation/devicetree/bindings/net/adi,adin.yaml
+++ b/Documentation/devicetree/bindings/net/adi,adin.yaml
@@ -52,6 +52,12 @@ properties:
description: Enable 25MHz reference clock output on CLK25_REF pin.
type: boolean
+ adi,low-cmode-impedance:
+ description: |
+ Ability to configure for the lowest common-mode impedance on the
+ receive pair for 100BASE-TX.
+ type: boolean
+
unevaluatedProperties: false
examples:
----- Message original -----
De: "Osose Itua" <osose.itua@savoirfairelinux.com>
À: "netdev" <netdev@vger.kernel.org>
Cc: "devicetree" <devicetree@vger.kernel.org>, "linux-kernel" <linux-kernel@vger.kernel.org>, "Michael Hennerich" <michael.hennerich@analog.com>, "Jérome Oufella" <jerome.oufella@savoirfairelinux.com>
Envoyé: Mardi 16 Décembre 2025 10:48:39
Objet: [PATCH 1/2] net: phy: adin: enable configuration of the LP Termination Register
From 9c68d9082a9c0550891f24c5902c1f0de15de949 Mon Sep 17 00:00:00 2001
From: Osose Itua <osose.itua@savoirfairelinux.com>
Date: Fri, 14 Nov 2025 17:00:14 -0500
Subject: [PATCH 1/2] net: phy: adin: enable configuration of the LP
Termination Register
The ADIN1200/ADIN1300 provide a control bit that selects between normal
receive termination and the lowest common mode impedance for 100BASE-TX
operation. This behavior is controlled through the Low Power Termination
register (B_100_ZPTM_EN_DIMRX).
Bit 0 of this register enables normal termination when set (this is the
default), and selects the lowest common mode impedance when cleared.
Signed-off-by: Osose Itua <osose.itua@savoirfairelinux.com>
---
drivers/net/phy/adin.c | 32 ++++++++++++++++++++++++++++++++
1 file changed, 32 insertions(+)
diff --git a/drivers/net/phy/adin.c b/drivers/net/phy/adin.c
index 7fa713ca8d45..2969480a7be3 100644
--- a/drivers/net/phy/adin.c
+++ b/drivers/net/phy/adin.c
@@ -89,6 +89,9 @@
#define ADIN1300_CLOCK_STOP_REG 0x9400
#define ADIN1300_LPI_WAKE_ERR_CNT_REG 0xa000
+#define ADIN1300_B_100_ZPTM_DIMRX 0xB685
+#define ADIN1300_B_100_ZPTM_EN_DIMRX BIT(0)
+
#define ADIN1300_CDIAG_RUN 0xba1b
#define ADIN1300_CDIAG_RUN_EN BIT(0)
@@ -522,6 +525,31 @@ static int adin_config_clk_out(struct phy_device *phydev)
ADIN1300_GE_CLK_CFG_MASK, sel);
}
+static int adin_config_zptm100(struct phy_device *phydev)
+{
+ struct device *dev = &phydev->mdio.dev;
+ u8 reg;
+ int rc;
+
+ if (!(device_property_read_bool(dev, "adi,low-cmode-impedance")))
+ return 0;
+
+ /* set to 0 to configure for lowest common-mode impedance */
+ rc = phy_write_mmd(phydev, MDIO_MMD_VEND1, ADIN1300_B_100_ZPTM_DIMRX, 0x0);
+ if (rc < 0)
+ return rc;
+
+ reg = phy_read_mmd(phydev, MDIO_MMD_VEND1, ADIN1300_B_100_ZPTM_DIMRX);
+ if (reg < 0)
+ return reg;
+
+ if (reg != 0x0)
+ phydev_err(phydev,
+ "Lowest common-mode impedance configuration failed\n");
+
+ return 0;
+}
+
static int adin_config_init(struct phy_device *phydev)
{
int rc;
@@ -548,6 +576,10 @@ static int adin_config_init(struct phy_device *phydev)
if (rc < 0)
return rc;
+ rc = adin_config_zptm100(phydev);
+ if (rc < 0)
+ return rc;
+
phydev_dbg(phydev, "PHY is using mode '%s'\n",
phy_modes(phydev->interface));
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [External] : [PATCH 1/2] net: phy: adin: enable configuration of the LP Termination Register
2025-12-16 15:48 [PATCH 1/2] net: phy: adin: enable configuration of the LP Termination Register Osose Itua
2025-12-16 15:50 ` [PATCH 2/2] dt-bindings: net: adi,adin: document LP termination property Osose Itua
@ 2025-12-16 17:02 ` ALOK TIWARI
1 sibling, 0 replies; 3+ messages in thread
From: ALOK TIWARI @ 2025-12-16 17:02 UTC (permalink / raw)
To: Osose Itua, netdev
Cc: devicetree, linux-kernel, Michael Hennerich, Jérôme Oufella
On 12/16/2025 9:18 PM, Osose Itua wrote:
> From 9c68d9082a9c0550891f24c5902c1f0de15de949 Mon Sep 17 00:00:00 2001
> From: Osose Itua <osose.itua@savoirfairelinux.com>
> Date: Fri, 14 Nov 2025 17:00:14 -0500
> Subject: [PATCH 1/2] net: phy: adin: enable configuration of the LP
> Termination Register
Double space between LP Termination.
>
> The ADIN1200/ADIN1300 provide a control bit that selects between normal
> receive termination and the lowest common mode impedance for 100BASE-TX
> operation. This behavior is controlled through the Low Power Termination
> register (B_100_ZPTM_EN_DIMRX).
>
> Bit 0 of this register enables normal termination when set (this is the
> default), and selects the lowest common mode impedance when cleared.
>
> Signed-off-by: Osose Itua <osose.itua@savoirfairelinux.com>
> ---
> drivers/net/phy/adin.c | 32 ++++++++++++++++++++++++++++++++
> 1 file changed, 32 insertions(+)
>
> diff --git a/drivers/net/phy/adin.c b/drivers/net/phy/adin.c
> index 7fa713ca8d45..2969480a7be3 100644
> --- a/drivers/net/phy/adin.c
> +++ b/drivers/net/phy/adin.c
> @@ -89,6 +89,9 @@
> #define ADIN1300_CLOCK_STOP_REG 0x9400
> #define ADIN1300_LPI_WAKE_ERR_CNT_REG 0xa000
>
> +#define ADIN1300_B_100_ZPTM_DIMRX 0xB685
> +#define ADIN1300_B_100_ZPTM_EN_DIMRX BIT(0)
> +
> #define ADIN1300_CDIAG_RUN 0xba1b
> #define ADIN1300_CDIAG_RUN_EN BIT(0)
>
> @@ -522,6 +525,31 @@ static int adin_config_clk_out(struct phy_device *phydev)
> ADIN1300_GE_CLK_CFG_MASK, sel);
> }
>
> +static int adin_config_zptm100(struct phy_device *phydev)
> +{
> + struct device *dev = &phydev->mdio.dev;
> + u8 reg;
> + int rc;
> +
> + if (!(device_property_read_bool(dev, "adi,low-cmode-impedance")))
> + return 0;
> +
> + /* set to 0 to configure for lowest common-mode impedance */
> + rc = phy_write_mmd(phydev, MDIO_MMD_VEND1, ADIN1300_B_100_ZPTM_DIMRX, 0x0);
> + if (rc < 0)
> + return rc;
> +
> + reg = phy_read_mmd(phydev, MDIO_MMD_VEND1, ADIN1300_B_100_ZPTM_DIMRX);
phy_read_mmd return int, but u8 reg
reg < 0 will never be true
> + if (reg < 0)
> + return reg;
> +
> + if (reg != 0x0)
> + phydev_err(phydev,
> + "Lowest common-mode impedance configuration failed\n");
> +
> + return 0;
> +}
> +
> static int adin_config_init(struct phy_device *phydev)
> {
> int rc;
> @@ -548,6 +576,10 @@ static int adin_config_init(struct phy_device *phydev)
> if (rc < 0)
> return rc;
>
> + rc = adin_config_zptm100(phydev);
> + if (rc < 0)
> + return rc;
> +
> phydev_dbg(phydev, "PHY is using mode '%s'\n",
> phy_modes(phydev->interface));
>
>
^ permalink raw reply [flat|nested] 3+ messages in thread