driver: ptp_clock: PTP clock driver definition

Defines a PTP clock driver that can be implemented in those network
interface drivers that provide gPTP support.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Julien Chevrier <julien.chevrier@intel.com>

drivers/Kconfig

@@ -53,6 +53,8 @@ source "drivers/watchdog/Kconfig"
 
 source "drivers/clock_control/Kconfig"
 
+source "drivers/ptp_clock/Kconfig"
+
 source "drivers/ipm/Kconfig"
 
 source "drivers/aio/Kconfig"

drivers/ptp_clock/Kconfig

@@ -0,0 +1,11 @@
+#
+# Copyright (c) 2018 Intel Corporation.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+menuconfig PTP_CLOCK
+	bool "Precision Time Protocol Clock driver support"
+	default n
+	help
+	  Enable options for Precision Time Protocol Clock drivers.

include/net/ethernet.h

@@ -71,6 +71,9 @@ enum ethernet_hw_caps {
 
 	/** Changing duplex (half/full) supported */
 	ETHERNET_DUPLEX_SET		= BIT(7),
+
+	/** IEEE 802.1AS (gPTP) clock supported */
+	ETHERNET_PTP			= BIT(8),
 };
 
 enum ethernet_config_type {
@@ -129,6 +132,11 @@ struct ethernet_api {
 	int (*vlan_setup)(struct device *dev, struct net_if *iface,
 			  u16_t tag, bool enable);
 #endif /* CONFIG_NET_VLAN */
+
+#if defined(CONFIG_PTP_CLOCK)
+	/** Return ptp_clock device that is tied to this ethernet device */
+	struct device *(*get_ptp_clock)(struct device *eth_dev);
+#endif /* CONFIG_PTP_CLOCK */
 };
 
 struct net_eth_hdr {
@@ -406,6 +414,16 @@ void net_eth_carrier_on(struct net_if *iface);
  */
 void net_eth_carrier_off(struct net_if *iface);
 
+/**
+ * @brief Return PTP clock that is tied to this ethernet network interface.
+ *
+ * @param iface Network interface
+ *
+ * @return Pointer to PTP clock if found, NULL if not found or if this
+ * ethernet interface does not support PTP.
+ */
+struct device *net_eth_get_ptp_clock(struct net_if *iface);
+
 #ifdef __cplusplus
 }
 #endif

include/ptp_clock.h

@@ -0,0 +1,95 @@
+/*
+ * Copyright (c) 2018 Intel Corporation.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef _PTP_CLOCK_H_
+#define _PTP_CLOCK_H_
+
+#include <stdint.h>
+#include <device.h>
+#include <misc/util.h>
+#include <net/ptp_time.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Name of the PTP clock driver */
+#if !defined(PTP_CLOCK_NAME)
+#define PTP_CLOCK_NAME "PTP_CLOCK"
+#endif
+
+struct ptp_clock_driver_api {
+	int (*set)(struct device *dev, struct net_ptp_time *tm);
+	int (*get)(struct device *dev, struct net_ptp_time *tm);
+	int (*adjust)(struct device *dev, int increment);
+	int (*rate_adjust)(struct device *dev, float ratio);
+};
+
+/**
+ * @brief Set the time of the PTP clock.
+ *
+ * @param dev PTP clock device
+ * @param tm Time to set
+ *
+ * @return 0 if ok, <0 if error
+ */
+static inline int ptp_clock_set(struct device *dev, struct net_ptp_time *tm)
+{
+	const struct ptp_clock_driver_api *api = dev->driver_api;
+
+	return api->set(dev, tm);
+}
+
+/**
+ * @brief Get the time of the PTP clock.
+ *
+ * @param dev PTP clock device
+ * @param tm Where to store the current time.
+ *
+ * @return 0 if ok, <0 if error
+ */
+static inline int ptp_clock_get(struct device *dev, struct net_ptp_time *tm)
+{
+	const struct ptp_clock_driver_api *api = dev->driver_api;
+
+	return api->get(dev, tm);
+}
+
+/**
+ * @brief Adjust the PTP clock time.
+ *
+ * @param dev PTP clock device
+ * @param increment Increment of the clock in nanoseconds
+ *
+ * @return 0 if ok, <0 if error
+ */
+static inline int ptp_clock_adjust(struct device *dev, int increment)
+{
+	const struct ptp_clock_driver_api *api = dev->driver_api;
+
+	return api->adjust(dev, increment);
+}
+
+/**
+ * @brief Adjust the PTP clock time change rate when compared to its neighbor.
+ *
+ * @param dev PTP clock device
+ * @param rate Rate of the clock time change
+ *
+ * @return 0 if ok, <0 if error
+ */
+static inline int ptp_clock_rate_adjust(struct device *dev, float rate)
+{
+	const struct ptp_clock_driver_api *api = dev->driver_api;
+
+	return api->rate_adjust(dev, rate);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __PTP_CLOCK_H__ */

subsys/net/ip/l2/ethernet/ethernet.c

@@ -801,6 +801,26 @@ void net_eth_carrier_off(struct net_if *iface)
 	handle_carrier(ctx, iface, carrier_off);
 }
 
+struct device *net_eth_get_ptp_clock(struct net_if *iface)
+{
+#if defined(CONFIG_PTP_CLOCK)
+	struct device *dev = net_if_get_device(iface);
+	const struct ethernet_api *api = dev->driver_api;
+
+	if (net_if_l2(iface) != &NET_L2_GET_NAME(ETHERNET)) {
+		return NULL;
+	}
+
+	if (!(api->get_capabilities(dev) & ETHERNET_PTP)) {
+		return NULL;
+	}
+
+	return api->get_ptp_clock(net_if_get_device(iface));
+#else
+	return NULL;
+#endif
+}
+
 void ethernet_init(struct net_if *iface)
 {
 	struct ethernet_context *ctx = net_if_l2_data(iface);