device: Add function to retrieve counter values

Signed-off-by: Marc Schink <jaylink-dev@marcschink.de>

2 files changed, 95 insertions, 0 deletions

diff --git a/libjaylink/device.c b/libjaylink/device.c
index 8b4ad16..e14a304 100644
--- a/libjaylink/device.c
+++ b/libjaylink/device.c
@@ -43,6 +43,7 @@
 #define CMD_GET_HW_STATUS	0x07
 #define CMD_REGISTER		0x09
 #define CMD_GET_HW_INFO		0xc1
+#define CMD_GET_COUNTERS	0xc2
 #define CMD_GET_FREE_MEMORY	0xd4
 #define CMD_GET_CAPS		0xe8
 #define CMD_GET_EXT_CAPS	0xed
@@ -615,6 +616,85 @@ JAYLINK_API int jaylink_get_hardware_info(struct jaylink_device_handle *devh,
 }
 
 /**
+ * Retrieve the counter values of a device.
+ *
+ * @note This function must only be used if the device has the
+ *       #JAYLINK_DEV_CAP_GET_COUNTERS capability.
+ *
+ * @param[in,out] devh Device handle.
+ * @param[in] mask A bit field where each set bit represents a counter value to
+ *                 request. See #jaylink_counter for a description of the
+ *                 counters and their bit positions.
+ * @param[out] values Array to store the counter values on success. Its content
+ *                    is undefined on failure. The array must be large enough
+ *                    to contain at least as many elements as bits set in @p
+ *                    mask.
+ *
+ * @retval JAYLINK_OK Success.
+ * @retval JAYLINK_ERR_ARG Invalid arguments.
+ * @retval JAYLINK_ERR_TIMEOUT A timeout occurred.
+ * @retval JAYLINK_ERR_IO Input/output error.
+ * @retval JAYLINK_ERR Other error conditions.
+ *
+ * @since 0.2.0
+ */
+JAYLINK_API int jaylink_get_counters(struct jaylink_device_handle *devh,
+		uint32_t mask, uint32_t *values)
+{
+	int ret;
+	struct jaylink_context *ctx;
+	uint8_t buf[5];
+	unsigned int i;
+	unsigned int num;
+	unsigned int length;
+
+	if (!devh || !mask || !values)
+		return JAYLINK_ERR_ARG;
+
+	ctx = devh->dev->ctx;
+	num = 0;
+
+	for (i = 0; i < 32; i++) {
+		if (mask & (1 << i))
+			num++;
+	}
+
+	length = num * sizeof(uint32_t);
+	ret = transport_start_write_read(devh, 5, length, true);
+
+	if (ret != JAYLINK_OK) {
+		log_err(ctx, "transport_start_write_read() failed: %s.",
+			jaylink_strerror(ret));
+		return ret;
+	}
+
+	buf[0] = CMD_GET_COUNTERS;
+	buffer_set_u32(buf, mask, 1);
+
+	ret = transport_write(devh, buf, 5);
+
+	if (ret != JAYLINK_OK) {
+		log_err(ctx, "transport_write() failed: %s.",
+			jaylink_strerror(ret));
+		return ret;
+	}
+
+	ret = transport_read(devh, (uint8_t *)values, length);
+
+	if (ret != JAYLINK_OK) {
+		log_err(ctx, "transport_read() failed: %s.",
+			jaylink_strerror(ret));
+		return ret;
+	}
+
+	for (i = 0; i < num; i++)
+		values[i] = buffer_get_u32((uint8_t *)values,
+			i * sizeof(uint32_t));
+
+	return JAYLINK_OK;
+}
+
+/**
  * Retrieve the hardware version of a device.
  *
  * @note This function must only be used if the device has the
diff --git a/libjaylink/libjaylink.h b/libjaylink/libjaylink.h
index 9c34119..f3bb959 100644
--- a/libjaylink/libjaylink.h
+++ b/libjaylink/libjaylink.h
@@ -135,6 +135,8 @@ enum jaylink_device_capability {
 	JAYLINK_DEV_CAP_SET_TARGET_POWER = 13,
 	/** Device supports target interface selection. */
 	JAYLINK_DEV_CAP_SELECT_TIF = 17,
+	/** Device supports retrieval of counter values. */
+	JAYLINK_DEV_CAP_GET_COUNTERS = 19,
 	/** Device supports capturing of SWO trace data. */
 	JAYLINK_DEV_CAP_SWO = 23,
 	/** Device supports file I/O operations. */
@@ -166,6 +168,17 @@ enum jaylink_hardware_info {
 	JAYLINK_HW_INFO_ITARGET_PEAK = (1 << 3)
 };
 
+/** Device counters. */
+enum jaylink_counter {
+	/** Time the device is connected to a target in milliseconds. */
+	JAYLINK_COUNTER_TARGET_TIME = (1 << 0),
+	/**
+	 * Number of times the device was connected or disconnected from a
+	 * target.
+	 */
+	JAYLINK_COUNTER_TARGET_CONNECTIONS = (1 << 1)
+};
+
 /** Device hardware types. */
 enum jaylink_hardware_type {
 	/** J-Link. */
@@ -411,6 +424,8 @@ JAYLINK_API int jaylink_get_firmware_version(
 		size_t *length);
 JAYLINK_API int jaylink_get_hardware_info(struct jaylink_device_handle *devh,
 		uint32_t mask, uint32_t *info);
+JAYLINK_API int jaylink_get_counters(struct jaylink_device_handle *devh,
+		uint32_t mask, uint32_t *values);
 JAYLINK_API int jaylink_get_hardware_version(
 		struct jaylink_device_handle *devh,
 		struct jaylink_hardware_version *version);