pbio/drv/usb: Use out buffers from drivers.

The platform specific drivers have specific requirements and cleanups for the outgoing data, and they have different buffers for each. So get those buffers instead of using a local one.

Author: laurensvalk

lib/pbio/drv/usb/usb.c

@@ -12,10 +12,13 @@
 #include <unistd.h>
 
 #include "usb.h"
+
+#include <pbdrv/config.h>
 #include <pbdrv/usb.h>
 
 #include <pbio/error.h>
 #include <pbio/os.h>
+#include <pbio/protocol.h>
 
 #include <lwrb/lwrb.h>
 
@@ -25,7 +28,7 @@
 static bool pbdrv_usb_events_subscribed;
 
 bool pbdrv_usb_connection_is_active(void) {
-    return pbdrv_usb_events_subscribed;
+    return pbdrv_usb_events_subscribed && pbdrv_usb_is_ready();
 }
 
 /**
@@ -106,7 +109,7 @@ static void pbdrv_usb_handle_data_in(void) {
         return;
     }
 
-    static uint8_t data_in[PBDRV_USB_PYBRICKS_MAX_PACKET_SIZE];
+    static uint8_t data_in[PBDRV_CONFIG_USB_MAX_PACKET_SIZE];
     uint32_t size = pbdrv_usb_get_data_in(data_in);
 
     // Expecting at least EP_MSG and payload.
@@ -145,7 +148,7 @@ static pbio_error_t pbdrv_usb_process_thread(pbio_os_state_t *state, void *conte
 
     static pbio_os_state_t sub;
 
-    static uint8_t out_data[PBDRV_USB_PYBRICKS_MAX_PACKET_SIZE];
+    static uint8_t *out_data;
     static uint32_t out_size;
 
     pbio_error_t err;
@@ -166,21 +169,21 @@ static pbio_error_t pbdrv_usb_process_thread(pbio_os_state_t *state, void *conte
             // status, then stdout, then other events.
             if (respond_soon) {
                 // Pack the response to the most recent message.
-                out_data[0] = PBIO_PYBRICKS_IN_EP_MSG_RESPONSE;
+                pbdrv_usb_tx_get_buf(PBIO_PYBRICKS_IN_EP_MSG_RESPONSE, &out_data);
                 pbio_set_uint32_le(&out_data[1], respond_result);
                 out_size = sizeof(uint32_t) + 1;
                 respond_soon = false;
             } else if (pbdrv_usb_connection_is_active() && status_data_pending) {
                 // Send out status if pending (already includes event code).
-                out_data[0] = PBIO_PYBRICKS_IN_EP_MSG_EVENT;
+                pbdrv_usb_tx_get_buf(PBIO_PYBRICKS_IN_EP_MSG_EVENT, &out_data);
                 memcpy(&out_data[1], status_data, PBIO_PYBRICKS_EVENT_STATUS_REPORT_SIZE);
                 out_size = PBIO_PYBRICKS_USB_MESSAGE_SIZE(PBIO_PYBRICKS_EVENT_STATUS_REPORT_SIZE);
                 status_data_pending = false;
             } else if (pbdrv_usb_connection_is_active() && lwrb_get_full(&stdout_ring_buf) != 0) {
                 // Send out stdout if anything is buffered.
-                out_data[0] = PBIO_PYBRICKS_IN_EP_MSG_EVENT;
+                uint32_t max_size = pbdrv_usb_tx_get_buf(PBIO_PYBRICKS_IN_EP_MSG_EVENT, &out_data);
                 out_data[1] = PBIO_PYBRICKS_EVENT_WRITE_STDOUT;
-                out_size = lwrb_read(&stdout_ring_buf, &out_data[2], PBDRV_USB_PYBRICKS_MAX_PACKET_SIZE - 2) + 2;
+                out_size = lwrb_read(&stdout_ring_buf, &out_data[2], max_size - 2) + 2;
             }
 
             // If there was anything to send, send it.
@@ -210,7 +213,7 @@ static pbio_error_t pbdrv_usb_process_thread(pbio_os_state_t *state, void *conte
 void pbdrv_usb_init(void) {
     pbdrv_usb_init_device();
 
-    static uint8_t stdout_buf[PBDRV_USB_PYBRICKS_MAX_PACKET_SIZE * 2];
+    static uint8_t stdout_buf[PBDRV_CONFIG_USB_MAX_PACKET_SIZE * 2];
     lwrb_init(&stdout_ring_buf, stdout_buf, PBIO_ARRAY_SIZE(stdout_buf));
 
     pbio_os_process_start(&pbdrv_usb_process, pbdrv_usb_process_thread, NULL);

lib/pbio/drv/usb/usb.h

@@ -12,11 +12,10 @@
 
 #include <pbio/error.h>
 #include <pbio/os.h>
+#include <pbio/protocol.h>
 
 #include <stdint.h>
 
-// revisit, this is also defined elsewhere
-#define PBDRV_USB_PYBRICKS_MAX_PACKET_SIZE (64u)
 #define PBDRV_USB_TRANSMIT_TIMEOUT (50)
 
 /**
@@ -49,6 +48,15 @@ void pbdrv_usb_deinit_device(void);
  */
 uint32_t pbdrv_usb_get_data_in(uint8_t *data);
 
+/**
+ * Gets the buffer to match the given endpoint mesage type.
+ *
+ * @param [in]  message_type The message type to find the buffer for
+ * @param [out] buf          The corresponding buffer to write data to before sending.
+ * @return                   Maximum size to write.
+ */
+uint32_t pbdrv_usb_tx_get_buf(pbio_pybricks_usb_in_ep_msg_t message_type, uint8_t **buf);
+
 /**
  * Sends and awaits message from hub to host via the Pybricks USB interface OUT endpoint.
  *
@@ -126,6 +134,10 @@ static inline bool pbdrv_usb_is_ready(void) {
     return false;
 }
 
+static inline uint32_t pbdrv_usb_tx_get_buf(pbio_pybricks_usb_in_ep_msg_t message_type, uint8_t **buf) {
+    return 0;
+}
+
 
 #endif // PBDRV_CONFIG_USB
 

lib/pbio/drv/usb/usb_simulation.c

@@ -29,6 +29,15 @@ pbdrv_usb_bcd_t pbdrv_usb_get_bcd(void) {
     return PBDRV_USB_BCD_NONE;
 }
 
+static uint8_t pbdrv_usb_tx_buf[PBDRV_CONFIG_USB_MAX_PACKET_SIZE];
+
+uint32_t pbdrv_usb_tx_get_buf(pbio_pybricks_usb_in_ep_msg_t message_type, uint8_t **buf) {
+    // We can just use the same buffer for any transfer in this simulation.
+    pbdrv_usb_tx_buf[0] = message_type;
+    *buf = pbdrv_usb_tx_buf;
+    return sizeof(pbdrv_usb_tx_buf);
+}
+
 pbio_error_t pbdrv_usb_tx(pbio_os_state_t *state, const uint8_t *data, uint32_t size) {
 
     static pbio_os_timer_t timer;
@@ -53,13 +62,13 @@ pbio_error_t pbdrv_usb_tx_reset(pbio_os_state_t *state) {
     return PBIO_SUCCESS;
 }
 
-static uint8_t usb_in_buf[PBDRV_USB_PYBRICKS_MAX_PACKET_SIZE];
+static uint8_t usb_in_buf[PBDRV_CONFIG_USB_MAX_PACKET_SIZE];
 static uint32_t usb_in_size;
 
 uint32_t pbdrv_usb_get_data_in(uint8_t *data) {
 
     // Invalid size.
-    if (usb_in_size > PBDRV_USB_PYBRICKS_MAX_PACKET_SIZE) {
+    if (usb_in_size > PBDRV_CONFIG_USB_MAX_PACKET_SIZE) {
         usb_in_size = 0;
     }
 

lib/pbio/include/pbio/protocol.h

@@ -457,23 +457,23 @@ enum {
 // 0 is skipped to avoid a zeroed buffer from being misinterpreted as a message.
 
 /** Hub to host messages via the Pybricks interface IN endpoint. */
-enum {
+typedef enum {
     /**
      * Analog of BLE status response. Emitted in response to every OUT message
      * received.
      */
     PBIO_PYBRICKS_IN_EP_MSG_RESPONSE = 1,
     /**Analog to BLE notification. Only emitted if subscribed. */
     PBIO_PYBRICKS_IN_EP_MSG_EVENT = 2,
-};
+} pbio_pybricks_usb_in_ep_msg_t;
 
 /** Host to hub messages via the Pybricks USB interface OUT endpoint. */
-enum {
+typedef enum {
     /** Analog of BLE Client Characteristic Configuration Descriptor (CCCD). */
     PBIO_PYBRICKS_OUT_EP_MSG_SUBSCRIBE = 1,
     /** Analog of BLE Client Characteristic Write with response. */
     PBIO_PYBRICKS_OUT_EP_MSG_COMMAND = 2,
-};
+} pbio_pybricks_usb_out_ep_msg_t;
 
 /**
  * Size of USB messages for Pybricks USB interface.

lib/pbio/platform/virtual_hub/pbdrvconfig.h

@@ -42,6 +42,7 @@
 #define PBDRV_CONFIG_HAS_PORT_VCC_CONTROL                   (1)
 
 #define PBDRV_CONFIG_USB                                    (1)
+#define PBDRV_CONFIG_USB_MAX_PACKET_SIZE                    (64)
 #define PBDRV_CONFIG_USB_SIMULATION                         (1)
 #define PBDRV_CONFIG_USB_MFG_STR                            u"Pybricks"
 #define PBDRV_CONFIG_USB_PROD_STR                           u"Virtual Hub"