1 files changed, 271 insertions, 0 deletions
diff --git a/include/linux/hte.h b/include/linux/hte.h
new file mode 100644
index 000000000000..8289055061ab
--- /dev/null
+++ b/include/linux/hte.h
@@ -0,0 +1,271 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __LINUX_HTE_H
+#define __LINUX_HTE_H
+
+#include <linux/errno.h>
+
+struct hte_chip;
+struct hte_device;
+struct of_phandle_args;
+
+/**
+ * enum hte_edge - HTE line edge flags.
+ *
+ * @HTE_EDGE_NO_SETUP: No edge setup. In this case consumer will setup edges,
+ * for example during request irq call.
+ * @HTE_RISING_EDGE_TS: Rising edge.
+ * @HTE_FALLING_EDGE_TS: Falling edge.
+ *
+ */
+enum hte_edge {
+	HTE_EDGE_NO_SETUP = 1U << 0,
+	HTE_RISING_EDGE_TS = 1U << 1,
+	HTE_FALLING_EDGE_TS = 1U << 2,
+};
+
+/**
+ * enum hte_return - HTE subsystem return values used during callback.
+ *
+ * @HTE_CB_HANDLED: The consumer handled the data.
+ * @HTE_RUN_SECOND_CB: The consumer needs further processing, in that case
+ * HTE subsystem calls secondary callback provided by the consumer where it
+ * is allowed to sleep.
+ */
+enum hte_return {
+	HTE_CB_HANDLED,
+	HTE_RUN_SECOND_CB,
+};
+
+/**
+ * struct hte_ts_data - HTE timestamp data.
+ *
+ * @tsc: Timestamp value.
+ * @seq: Sequence counter of the timestamps.
+ * @raw_level: Level of the line at the timestamp if provider supports it,
+ * -1 otherwise.
+ */
+struct hte_ts_data {
+	u64 tsc;
+	u64 seq;
+	int raw_level;
+};
+
+/**
+ * struct hte_clk_info - Clock source info that HTE provider uses to timestamp.
+ *
+ * @hz: Supported clock rate in HZ, for example 1KHz clock = 1000.
+ * @type: Supported clock type.
+ */
+struct hte_clk_info {
+	u64 hz;
+	clockid_t type;
+};
+
+/**
+ * typedef hte_ts_cb_t - HTE timestamp data processing primary callback.
+ *
+ * The callback is used to push timestamp data to the client and it is
+ * not allowed to sleep.
+ *
+ * @ts: HW timestamp data.
+ * @data: Client supplied data.
+ */
+typedef enum hte_return (*hte_ts_cb_t)(struct hte_ts_data *ts, void *data);
+
+/**
+ * typedef hte_ts_sec_cb_t - HTE timestamp data processing secondary callback.
+ *
+ * This is used when the client needs further processing where it is
+ * allowed to sleep.
+ *
+ * @data: Client supplied data.
+ *
+ */
+typedef enum hte_return (*hte_ts_sec_cb_t)(void *data);
+
+/**
+ * struct hte_line_attr - Line attributes.
+ *
+ * @line_id: The logical ID understood by the consumers and providers.
+ * @line_data: Line data related to line_id.
+ * @edge_flags: Edge setup flags.
+ * @name: Descriptive name of the entity that is being monitored for the
+ * hardware timestamping. If null, HTE core will construct the name.
+ *
+ */
+struct hte_line_attr {
+	u32 line_id;
+	void *line_data;
+	unsigned long edge_flags;
+	const char *name;
+};
+
+/**
+ * struct hte_ts_desc - HTE timestamp descriptor.
+ *
+ * This structure is a communication token between consumers to subsystem
+ * and subsystem to providers.
+ *
+ * @attr: The line attributes.
+ * @hte_data: Subsystem's private data, set by HTE subsystem.
+ */
+struct hte_ts_desc {
+	struct hte_line_attr attr;
+	void *hte_data;
+};
+
+/**
+ * struct hte_ops - HTE operations set by providers.
+ *
+ * @request: Hook for requesting a HTE timestamp. Returns 0 on success,
+ * non-zero for failures.
+ * @release: Hook for releasing a HTE timestamp. Returns 0 on success,
+ * non-zero for failures.
+ * @enable: Hook to enable the specified timestamp. Returns 0 on success,
+ * non-zero for failures.
+ * @disable: Hook to disable specified timestamp. Returns 0 on success,
+ * non-zero for failures.
+ * @get_clk_src_info: Hook to get the clock information the provider uses
+ * to timestamp. Returns 0 for success and negative error code for failure. On
+ * success HTE subsystem fills up provided struct hte_clk_info.
+ *
+ * xlated_id parameter is used to communicate between HTE subsystem and the
+ * providers and is translated by the provider.
+ */
+struct hte_ops {
+	int (*request)(struct hte_chip *chip, struct hte_ts_desc *desc,
+		       u32 xlated_id);
+	int (*release)(struct hte_chip *chip, struct hte_ts_desc *desc,
+		       u32 xlated_id);
+	int (*enable)(struct hte_chip *chip, u32 xlated_id);
+	int (*disable)(struct hte_chip *chip, u32 xlated_id);
+	int (*get_clk_src_info)(struct hte_chip *chip,
+				struct hte_clk_info *ci);
+};
+
+/**
+ * struct hte_chip - Abstract HTE chip.
+ *
+ * @name: functional name of the HTE IP block.
+ * @dev: device providing the HTE.
+ * @ops: callbacks for this HTE.
+ * @nlines: number of lines/signals supported by this chip.
+ * @xlate_of: Callback which translates consumer supplied logical ids to
+ * physical ids, return 0 for the success and negative for the failures.
+ * It stores (between 0 to @nlines) in xlated_id parameter for the success.
+ * @xlate_plat: Same as above but for the consumers with no DT node.
+ * @match_from_linedata: Match HTE device using the line_data.
+ * @of_hte_n_cells: Number of cells used to form the HTE specifier.
+ * @gdev: HTE subsystem abstract device, internal to the HTE subsystem.
+ * @data: chip specific private data.
+ */
+struct hte_chip {
+	const char *name;
+	struct device *dev;
+	const struct hte_ops *ops;
+	u32 nlines;
+	int (*xlate_of)(struct hte_chip *gc,
+			const struct of_phandle_args *args,
+			struct hte_ts_desc *desc, u32 *xlated_id);
+	int (*xlate_plat)(struct hte_chip *gc, struct hte_ts_desc *desc,
+			 u32 *xlated_id);
+	bool (*match_from_linedata)(const struct hte_chip *chip,
+				    const struct hte_ts_desc *hdesc);
+	u8 of_hte_n_cells;
+
+	struct hte_device *gdev;
+	void *data;
+};
+
+#if IS_ENABLED(CONFIG_HTE)
+/* HTE APIs for the providers */
+int devm_hte_register_chip(struct hte_chip *chip);
+int hte_push_ts_ns(const struct hte_chip *chip, u32 xlated_id,
+		   struct hte_ts_data *data);
+
+/* HTE APIs for the consumers */
+int hte_init_line_attr(struct hte_ts_desc *desc, u32 line_id,
+		       unsigned long edge_flags, const char *name,
+		       void *data);
+int hte_ts_get(struct device *dev, struct hte_ts_desc *desc, int index);
+int hte_ts_put(struct hte_ts_desc *desc);
+int hte_request_ts_ns(struct hte_ts_desc *desc, hte_ts_cb_t cb,
+		      hte_ts_sec_cb_t tcb, void *data);
+int devm_hte_request_ts_ns(struct device *dev, struct hte_ts_desc *desc,
+			   hte_ts_cb_t cb, hte_ts_sec_cb_t tcb, void *data);
+int of_hte_req_count(struct device *dev);
+int hte_enable_ts(struct hte_ts_desc *desc);
+int hte_disable_ts(struct hte_ts_desc *desc);
+int hte_get_clk_src_info(const struct hte_ts_desc *desc,
+			 struct hte_clk_info *ci);
+
+#else /* !CONFIG_HTE */
+static inline int devm_hte_register_chip(struct hte_chip *chip)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int hte_push_ts_ns(const struct hte_chip *chip,
+				 u32 xlated_id,
+				 const struct hte_ts_data *data)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int hte_init_line_attr(struct hte_ts_desc *desc, u32 line_id,
+				     unsigned long edge_flags,
+				     const char *name, void *data)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int hte_ts_get(struct device *dev, struct hte_ts_desc *desc,
+			     int index)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int hte_ts_put(struct hte_ts_desc *desc)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int hte_request_ts_ns(struct hte_ts_desc *desc, hte_ts_cb_t cb,
+				    hte_ts_sec_cb_t tcb, void *data)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int devm_hte_request_ts_ns(struct device *dev,
+					 struct hte_ts_desc *desc,
+					 hte_ts_cb_t cb,
+					 hte_ts_sec_cb_t tcb,
+					 void *data)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int of_hte_req_count(struct device *dev)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int hte_enable_ts(struct hte_ts_desc *desc)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int hte_disable_ts(struct hte_ts_desc *desc)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int hte_get_clk_src_info(const struct hte_ts_desc *desc,
+				       struct hte_clk_info *ci)
+{
+	return -EOPNOTSUPP;
+}
+#endif /* !CONFIG_HTE */
+
+#endif