ec_host_cmd: introduce Host Command state

Introduce a current state of Host Command subsystem. It makes sures that a backend has been initilized and doesn't allow sending a response twice. There is a possibility, that a command handler that calls ec_host_cmd_send_response function returns anyway (which is a mistake). Signed-off-by: Dawid Niedzwiecki <[email protected]>
zephyrproject-rtos · Mar 6, 2024 · 4d97dcf · 4d97dcf
1 parent 99fd397
commit 4d97dcf
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diff --git a/include/zephyr/mgmt/ec_host_cmd/ec_host_cmd.h b/include/zephyr/mgmt/ec_host_cmd/ec_host_cmd.h
@@ -78,6 +78,13 @@ enum ec_host_cmd_log_level {
 	EC_HOST_CMD_DEBUG_MODES /* Number of host command debug modes */
 };
 
+enum ec_host_cmd_state {
+	EC_HOST_CMD_STATE_DISABLED = 0,
+	EC_HOST_CMD_STATE_RECEIVING,
+	EC_HOST_CMD_STATE_PROCESSING,
+	EC_HOST_CMD_STATE_SENDING,
+};
+
 typedef void (*ec_host_cmd_user_cb_t)(const struct ec_host_cmd_rx_ctx *rx_ctx, void *user_data);
 typedef enum ec_host_cmd_status (*ec_host_cmd_in_progress_cb_t)(void *user_data);
 
@@ -98,6 +105,7 @@ struct ec_host_cmd {
 	 */
 	ec_host_cmd_user_cb_t user_cb;
 	void *user_data;
+	enum ec_host_cmd_state state;
 #ifdef CONFIG_EC_HOST_CMD_DEDICATED_THREAD
 	struct k_thread thread;
 #endif /* CONFIG_EC_HOST_CMD_DEDICATED_THREAD */

diff --git a/subsys/mgmt/ec_host_cmd/ec_host_cmd_handler.c b/subsys/mgmt/ec_host_cmd/ec_host_cmd_handler.c
@@ -292,6 +292,12 @@ int ec_host_cmd_send_response(enum ec_host_cmd_status status,
 	struct ec_host_cmd *hc = &ec_host_cmd;
 	struct ec_host_cmd_tx_buf *tx = &hc->tx;
 
+	if (hc->state != EC_HOST_CMD_STATE_PROCESSING) {
+		LOG_ERR("Unexpected state while sending");
+		return -ENOTSUP;
+	}
+	hc->state = EC_HOST_CMD_STATE_SENDING;
+
 	if (status != EC_HOST_CMD_SUCCESS) {
 		const struct ec_host_cmd_request_header *const rx_header =
 			(const struct ec_host_cmd_request_header *const)hc->rx_ctx.buf;
@@ -390,9 +396,13 @@ FUNC_NORETURN static void ec_host_cmd_thread(void *hc_handle, void *arg2, void *
 		.reserved = NULL,
 	};
 
+	__ASSERT(hc->state != EC_HOST_CMD_STATE_DISABLED, "HC backend not initialized");
+
 	while (1) {
+		hc->state = EC_HOST_CMD_STATE_RECEIVING;
 		/* Wait until RX messages is received on host interface */
 		k_sem_take(&hc->rx_ready, K_FOREVER);
+		hc->state = EC_HOST_CMD_STATE_PROCESSING;
 
 		ec_host_cmd_log_request(rx->buf);
 
@@ -485,6 +495,8 @@ int ec_host_cmd_init(struct ec_host_cmd_backend *backend)
 		return -EIO;
 	}
 
+	hc->state = EC_HOST_CMD_STATE_RECEIVING;
+
 	/* Check if a backend uses provided buffers. The buffer pointers can be shifted within the
 	 * buffer to make space for preamble. Make sure the rx/tx pointers are within the provided
 	 * buffers ranges.