[net-next,v4,5/8] net: phy: introduce optional polling interface for PHY statistics

Commit Message

Oleksij Rempel Dec. 21, 2024, 8:15 a.m. UTC

Add an optional polling interface for PHY statistics to simplify driver
implementation.

Signed-off-by: Oleksij Rempel <[e-mail]>
---
changes v3:
- update commit message
changes v2:
- drop PHY_POLL_STATS
- add function comments
---
 drivers/net/phy/phy.c | 20 ++++++++++++++++++++
 include/linux/phy.h   | 21 +++++++++++++++++++++
 2 files changed, 41 insertions(+)

Patch

diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index e4b04cdaa995..c8812a115114 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -1398,6 +1398,23 @@  static int phy_enable_interrupts(struct phy_device *phydev)
 	return phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 }
 
+/**
+ * phy_update_stats - Update PHY device statistics if supported.
+ * @phydev: Pointer to the PHY device structure.
+ *
+ * If the PHY driver provides an update_stats callback, this function
+ * invokes it to update the PHY statistics. If not, it returns 0.
+ *
+ * Return: 0 on success, or a negative error code if the callback fails.
+ */
+static int phy_update_stats(struct phy_device *phydev)
+{
+	if (!phydev->drv->update_stats)
+		return 0;
+
+	return phydev->drv->update_stats(phydev);
+}
+
 /**
  * phy_request_interrupt - request and enable interrupt for a PHY device
  * @phydev: target phy_device struct
@@ -1467,6 +1484,9 @@  static enum phy_state_work _phy_state_machine(struct phy_device *phydev)
 	case PHY_RUNNING:
 		err = phy_check_link_status(phydev);
 		func = &phy_check_link_status;
+
+		if (!err)
+			err = phy_update_stats(phydev);
 		break;
 	case PHY_CABLETEST:
 		err = phydev->drv->cable_test_get_status(phydev, &finished);
diff --git a/include/linux/phy.h b/include/linux/phy.h
index d74ec55c3908..fdd0e6012e26 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -1177,6 +1177,24 @@  struct phy_driver {
 	 */
 	void (*get_link_stats)(struct phy_device *dev,
 			       struct ethtool_link_ext_stats *link_stats);
+
+	/**
+	 * @update_stats: Trigger periodic statistics updates.
+	 * @dev: The PHY device for which statistics updates are triggered.
+	 *
+	 * Periodically gathers statistics from the PHY device to update locally
+	 * maintained 64-bit counters. This is necessary for PHYs that implement
+	 * reduced-width counters (e.g., 16-bit or 32-bit) which can overflow
+	 * more frequently compared to 64-bit counters. By invoking this
+	 * callback, drivers can fetch the current counter values, handle
+	 * overflow detection, and accumulate the results into local 64-bit
+	 * counters for accurate reporting through the `get_phy_stats` and
+	 * `get_link_stats` interfaces.
+	 *
+	 * Return: 0 on success or a negative error code on failure.
+	 */
+	int (*update_stats)(struct phy_device *dev);
+
 	/** @get_sset_count: Number of statistic counters */
 	int (*get_sset_count)(struct phy_device *dev);
 	/** @get_strings: Names of the statistic counters */
@@ -1667,6 +1685,9 @@  static inline bool phy_polling_mode(struct phy_device *phydev)
 		if (phydev->drv->flags & PHY_POLL_CABLE_TEST)
 			return true;
 
+	if (phydev->drv->update_stats)
+		return true;
+
 	return phydev->irq == PHY_POLL;
 }