ethtool: add interface to interact with Ethernet Power Equipment

Add interface to support Power Sourcing Equipment. At current step it
provides generic way to address all variants of PSE devices as defined
in IEEE 802.3-2018 but support only objects specified for IEEE 802.3-2018 104.4
PoDL Power Sourcing Equipment (PSE).

Currently supported and mandatory objects are:
IEEE 802.3-2018 30.15.1.1.3 aPoDLPSEPowerDetectionStatus
IEEE 802.3-2018 30.15.1.1.2 aPoDLPSEAdminState
IEEE 802.3-2018 30.15.1.2.1 acPoDLPSEAdminControl

This is minimal interface needed to control PSE on each separate
ethernet port but it provides not all mandatory objects specified in
IEEE 802.3-2018.

Since "PoDL PSE" and "PSE" have similar names, but some different values
I decide to not merge them and keep separate naming schema. This should
allow as to be as close to IEEE 802.3 spec as possible and avoid name
conflicts in the future.

This implementation is connected to PHYs instead of MACs because PSE
auto classification can potentially interfere with PHY auto negotiation.
So, may be some extra PHY related initialization will be needed.

With WIP version of ethtools interaction with PSE capable link looks
as following:

$ ip l
...
5: t1l1@eth0: <BROADCAST,MULTICAST> ..
...

$ ethtool --show-pse t1l1
PSE attributs for t1l1:
PoDL PSE Admin State: disabled
PoDL PSE Power Detection Status: disabled

$ ethtool --set-pse t1l1 podl-pse-admin-control enable
$ ethtool --show-pse t1l1
PSE attributs for t1l1:
PoDL PSE Admin State: enabled
PoDL PSE Power Detection Status: delivering power

Signed-off-by: kernel test robot <lkp@intel.com>
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

3 files changed, 123 insertions, 0 deletions

diff --git a/include/linux/pse-pd/pse.h b/include/linux/pse-pd/pse.h
index 3ba787a48b15..fd1a916eeeba 100644
--- a/include/linux/pse-pd/pse.h
+++ b/include/linux/pse-pd/pse.h
@@ -9,6 +9,47 @@
 #include <linux/list.h>
 #include <uapi/linux/ethtool.h>
 
+struct phy_device;
+struct pse_controller_dev;
+
+/**
+ * struct pse_control_config - PSE control/channel configuration.
+ *
+ * @admin_cotrol: set PoDL PSE admin control as described in
+ *	IEEE 802.3-2018 30.15.1.2.1 acPoDLPSEAdminControl
+ */
+struct pse_control_config {
+	enum ethtool_podl_pse_admin_state admin_cotrol;
+};
+
+/**
+ * struct pse_control_status - PSE control/channel status.
+ *
+ * @podl_admin_state: operational state of the PoDL PSE
+ *	functions. IEEE 802.3-2018 30.15.1.1.2 aPoDLPSEAdminState
+ * @podl_pw_status: power detection status of the PoDL PSE.
+ *	IEEE 802.3-2018 30.15.1.1.3 aPoDLPSEPowerDetectionStatus:
+ */
+struct pse_control_status {
+	enum ethtool_podl_pse_admin_state podl_admin_state;
+	enum ethtool_podl_pse_pw_d_status podl_pw_status;
+};
+
+/**
+ * struct pse_controller_ops - PSE controller driver callbacks
+ *
+ * @ethtool_get_status: get PSE control status for ethtool interface
+ * @ethtool_set_config: set PSE control configuration over ethtool interface
+ */
+struct pse_controller_ops {
+	int (*ethtool_get_status)(struct pse_controller_dev *pcdev,
+		unsigned long id, struct netlink_ext_ack *extack,
+		struct pse_control_status *status);
+	int (*ethtool_set_config)(struct pse_controller_dev *pcdev,
+		unsigned long id, struct netlink_ext_ack *extack,
+		const struct pse_control_config *config);
+};
+
 struct module;
 struct device_node;
 struct of_phandle_args;
@@ -51,6 +92,13 @@ int devm_pse_controller_register(struct device *dev,
 struct pse_control *of_pse_control_get(struct device_node *node);
 void pse_control_put(struct pse_control *psec);
 
+int pse_ethtool_get_status(struct pse_control *psec,
+			   struct netlink_ext_ack *extack,
+			   struct pse_control_status *status);
+int pse_ethtool_set_config(struct pse_control *psec,
+			   struct netlink_ext_ack *extack,
+			   const struct pse_control_config *config);
+
 #else
 
 static inline struct pse_control *of_pse_control_get(struct device_node *node)
@@ -62,6 +110,20 @@ static inline void pse_control_put(struct pse_control *psec)
 {
 }
 
+int pse_ethtool_get_status(struct pse_control *psec,
+			   struct netlink_ext_ack *extack,
+			   struct pse_control_status *status)
+{
+	return -ENOTSUPP;
+}
+
+int pse_ethtool_set_config(struct pse_control *psec,
+			   struct netlink_ext_ack *extack,
+			   const struct pse_control_config *config)
+{
+	return -ENOTSUPP;
+}
+
 #endif
 
 #endif
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index fe9893d1485d..dc2aa3d75b39 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -737,6 +737,51 @@ enum ethtool_module_power_mode {
 };
 
 /**
+ * enum ethtool_podl_pse_admin_state - operational state of the PoDL PSE
+ *	functions. IEEE 802.3-2018 30.15.1.1.2 aPoDLPSEAdminState
+ * @ETHTOOL_PODL_PSE_ADMIN_STATE_UNKNOWN: state of PoDL PSE functions are
+ * 	unknown
+ * @ETHTOOL_PODL_PSE_ADMIN_STATE_DISABLED: PoDL PSE functions are disabled
+ * @ETHTOOL_PODL_PSE_ADMIN_STATE_ENABLED: PoDL PSE functions are enabled
+ */
+enum ethtool_podl_pse_admin_state {
+	ETHTOOL_PODL_PSE_ADMIN_STATE_UNKNOWN = 1,
+	ETHTOOL_PODL_PSE_ADMIN_STATE_DISABLED,
+	ETHTOOL_PODL_PSE_ADMIN_STATE_ENABLED,
+};
+
+/**
+ * enum ethtool_podl_pse_pw_d_status - power detection status of the PoDL PSE.
+ *	IEEE 802.3-2018 30.15.1.1.3 aPoDLPSEPowerDetectionStatus:
+ * @ETHTOOL_PODL_PSE_PW_D_STATUS_UNKNOWN: PoDL PSE
+ * @ETHTOOL_PODL_PSE_PW_D_STATUS_DISABLED: "The enumeration “disabled” is
+ *	asserted true when the PoDL PSE state diagram variable mr_pse_enable is
+ *	false"
+ * @ETHTOOL_PODL_PSE_PW_D_STATUS_SEARCHING: "The enumeration “searching” is
+ *	asserted true when either of the PSE state diagram variables
+ *	pi_detecting or pi_classifying is true."
+ * @ETHTOOL_PODL_PSE_PW_D_STATUS_DELIVERING: "The enumeration “deliveringPower”
+ *	is asserted true when the PoDL PSE state diagram variable pi_powered is
+ *	true."
+ * @ETHTOOL_PODL_PSE_PW_D_STATUS_SLEEP: "The enumeration “sleep” is asserted
+ *	true when the PoDL PSE state diagram variable pi_sleeping is true."
+ * @ETHTOOL_PODL_PSE_PW_D_STATUS_IDLE: "The enumeration “idle” is asserted true
+ *	when the logical combination of the PoDL PSE state diagram variables
+ *	pi_prebiased*!pi_sleeping is true."
+ * @ETHTOOL_PODL_PSE_PW_D_STATUS_ERROR: "The enumeration “error” is asserted
+ *	true when the PoDL PSE state diagram variable overload_held is true."
+ */
+enum ethtool_podl_pse_pw_d_status {
+	ETHTOOL_PODL_PSE_PW_D_STATUS_UNKNOWN = 1,
+	ETHTOOL_PODL_PSE_PW_D_STATUS_DISABLED,
+	ETHTOOL_PODL_PSE_PW_D_STATUS_SEARCHING,
+	ETHTOOL_PODL_PSE_PW_D_STATUS_DELIVERING,
+	ETHTOOL_PODL_PSE_PW_D_STATUS_SLEEP,
+	ETHTOOL_PODL_PSE_PW_D_STATUS_IDLE,
+	ETHTOOL_PODL_PSE_PW_D_STATUS_ERROR,
+};
+
+/**
  * struct ethtool_gstrings - string set for data tagging
  * @cmd: Command number = %ETHTOOL_GSTRINGS
  * @string_set: String set ID; one of &enum ethtool_stringset
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index 408a664fad59..bb57084ac524 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -49,6 +49,8 @@ enum {
 	ETHTOOL_MSG_PHC_VCLOCKS_GET,
 	ETHTOOL_MSG_MODULE_GET,
 	ETHTOOL_MSG_MODULE_SET,
+	ETHTOOL_MSG_PSE_GET,
+	ETHTOOL_MSG_PSE_SET,
 
 	/* add new constants above here */
 	__ETHTOOL_MSG_USER_CNT,
@@ -94,6 +96,7 @@ enum {
 	ETHTOOL_MSG_PHC_VCLOCKS_GET_REPLY,
 	ETHTOOL_MSG_MODULE_GET_REPLY,
 	ETHTOOL_MSG_MODULE_NTF,
+	ETHTOOL_MSG_PSE_GET_REPLY,
 
 	/* add new constants above here */
 	__ETHTOOL_MSG_KERNEL_CNT,
@@ -863,6 +866,19 @@ enum {
 	ETHTOOL_A_MODULE_MAX = (__ETHTOOL_A_MODULE_CNT - 1)
 };
 
+/* Power Sourcing Equipment */
+enum {
+	ETHTOOL_A_PSE_UNSPEC,
+	ETHTOOL_A_PSE_HEADER,			/* nest - _A_HEADER_* */
+	ETHTOOL_A_PODL_PSE_ADMIN_STATE,		/* u32 */
+	ETHTOOL_A_PODL_PSE_ADMIN_CONTROL,	/* u32 */
+	ETHTOOL_A_PODL_PSE_PW_D_STATUS,		/* u32 */
+
+	/* add new constants above here */
+	__ETHTOOL_A_PSE_CNT,
+	ETHTOOL_A_PSE_MAX = (__ETHTOOL_A_PSE_CNT - 1)
+};
+
 /* generic netlink info */
 #define ETHTOOL_GENL_NAME "ethtool"
 #define ETHTOOL_GENL_VERSION 1