pbio/sys/host: move stdin buffer to host from bluetooth

dlech · dlech · commit 41edda71350a · 2025-07-18T23:42:11.000-05:00
Move the stdin buffer from pbsys/bluetooth to pbsys/host so that it can
be used by other host interfaces, such as USB stdio. All connections
will share the same stdin buffer.

All function names are renames from "rx" to "stdin" to reflect the
current usage. The "rx" naming was a holdover from when this was
originally only used for Bluetooth RX via the Nordic UART Service.

A new PBSYS_CONFIG_HOST_STDIN_BUF_SIZE option is introduced to set a
platform-specific buffer size. Bluetooth-only hubs continue to use the
same size that was used in pbsys/bluetooth. Hubs with USB are set to
64 bytes to match the USB endpoint size.
diff --git a/bricks/_common_stm32/mphalport.c b/bricks/_common_stm32/mphalport.c
@@ -38,7 +38,7 @@ void mp_hal_delay_ms(mp_uint_t Delay) {
 uintptr_t mp_hal_stdio_poll(uintptr_t poll_flags) {
     uintptr_t ret = 0;
 
-    if ((poll_flags & MP_STREAM_POLL_RD) && pbsys_host_rx_get_available()) {
+    if ((poll_flags & MP_STREAM_POLL_RD) && pbsys_host_stdin_get_available()) {
         ret |= MP_STREAM_POLL_RD;
     }
 
@@ -51,7 +51,7 @@ int mp_hal_stdin_rx_chr(void) {
     uint8_t c;
 
     // wait for rx interrupt
-    while (size = 1, pbsys_host_rx(&c, &size) != PBIO_SUCCESS) {
+    while (size = 1, pbsys_host_stdin_read(&c, &size) != PBIO_SUCCESS) {
         MICROPY_EVENT_POLL_HOOK
     }
 
diff --git a/lib/pbio/include/pbsys/host.h b/lib/pbio/include/pbsys/host.h
@@ -26,33 +26,26 @@ typedef bool (*pbsys_host_stdin_event_callback_t)(uint8_t c);
 #if PBSYS_CONFIG_HOST
 
 void pbsys_host_init(void);
-void pbsys_host_rx_set_callback(pbsys_host_stdin_event_callback_t callback);
-void pbsys_host_rx_flush(void);
-uint32_t pbsys_host_rx_get_available(void);
-uint32_t pbsys_host_rx_get_free(void);
-void pbsys_host_rx_write(const uint8_t *data, uint32_t size);
-pbio_error_t pbsys_host_rx(uint8_t *data, uint32_t *size);
+uint32_t pbsys_host_stdin_get_free(void);
+void pbsys_host_stdin_write(const uint8_t *data, uint32_t size);
+void pbsys_host_stdin_set_callback(pbsys_host_stdin_event_callback_t callback);
+void pbsys_host_stdin_flush(void);
+uint32_t pbsys_host_stdin_get_available(void);
+pbio_error_t pbsys_host_stdin_read(uint8_t *data, uint32_t *size);
 pbio_error_t pbsys_host_tx(const uint8_t *data, uint32_t size);
 bool pbsys_host_tx_is_idle(void);
 
 #else // PBSYS_CONFIG_HOST
 
 #define pbsys_host_init()
-#define pbsys_host_rx_set_callback(callback)
-#define pbsys_host_rx_flush()
-#define pbsys_host_rx_get_available() 0
-#define pbsys_host_rx_get_free() 0
-#define pbsys_host_rx_write(data, size)
-
-static inline pbio_error_t pbsys_host_rx(uint8_t *data, uint32_t *size) {
-    return PBIO_ERROR_NOT_SUPPORTED;
-}
-static inline pbio_error_t pbsys_host_tx(const uint8_t *data, uint32_t size) {
-    return PBIO_ERROR_NOT_SUPPORTED;
-}
-static inline bool pbsys_host_tx_is_idle(void) {
-    return false;
-}
+#define pbsys_host_stdin_get_free() 0
+#define pbsys_host_stdin_write(data, size) { (void)(data); (void)(size); }
+#define pbsys_host_stdin_set_callback(callback) { (void)(callback); }
+#define pbsys_host_stdin_flush()
+#define pbsys_host_stdin_get_available() 0
+#define pbsys_host_stdin_read(data, size) PBIO_ERROR_NOT_SUPPORTED
+#define pbsys_host_tx(data, size) { (void)(data); (void)(size); PBIO_ERROR_NOT_SUPPORTED; }
+#define pbsys_host_tx_is_idle() false
 
 #endif // PBSYS_CONFIG_HOST
 
diff --git a/lib/pbio/platform/city_hub/pbsysconfig.h b/lib/pbio/platform/city_hub/pbsysconfig.h
@@ -13,6 +13,7 @@
 #define PBSYS_CONFIG_HMI_NUM_SLOTS                  (0)
 #define PBSYS_CONFIG_HUB_LIGHT_MATRIX               (0)
 #define PBSYS_CONFIG_HOST                           (1)
+#define PBSYS_CONFIG_HOST_STDIN_BUF_SIZE            (21)
 #define PBSYS_CONFIG_MAIN                           (1)
 #define PBSYS_CONFIG_STORAGE                        (1)
 #define PBSYS_CONFIG_STORAGE_NUM_SLOTS              (1)
diff --git a/lib/pbio/platform/essential_hub/pbsysconfig.h b/lib/pbio/platform/essential_hub/pbsysconfig.h
@@ -11,6 +11,7 @@
 #define PBSYS_CONFIG_HMI_NUM_SLOTS                  (0)
 #define PBSYS_CONFIG_HUB_LIGHT_MATRIX               (0)
 #define PBSYS_CONFIG_HOST                           (1)
+#define PBSYS_CONFIG_HOST_STDIN_BUF_SIZE            (64)
 #define PBSYS_CONFIG_MAIN                           (1)
 #define PBSYS_CONFIG_STORAGE                        (1)
 #define PBSYS_CONFIG_STORAGE_NUM_SLOTS              (1)
diff --git a/lib/pbio/platform/ev3/pbsysconfig.h b/lib/pbio/platform/ev3/pbsysconfig.h
@@ -7,6 +7,7 @@
 #define PBSYS_CONFIG_FEATURE_PROGRAM_FORMAT_MULTI_MPY_V6           (1)
 #define PBSYS_CONFIG_FEATURE_PROGRAM_FORMAT_MULTI_MPY_V6_3_NATIVE  (0)
 #define PBSYS_CONFIG_HOST                           (1)
+#define PBSYS_CONFIG_HOST_STDIN_BUF_SIZE            (21)
 #define PBSYS_CONFIG_MAIN                           (1)
 #define PBSYS_CONFIG_STORAGE                        (1)
 #define PBSYS_CONFIG_STORAGE_NUM_SLOTS              (1)
diff --git a/lib/pbio/platform/move_hub/pbsysconfig.h b/lib/pbio/platform/move_hub/pbsysconfig.h
@@ -13,6 +13,7 @@
 #define PBSYS_CONFIG_HMI_NUM_SLOTS                  (0)
 #define PBSYS_CONFIG_HUB_LIGHT_MATRIX               (0)
 #define PBSYS_CONFIG_HOST                           (1)
+#define PBSYS_CONFIG_HOST_STDIN_BUF_SIZE            (21)
 #define PBSYS_CONFIG_MAIN                           (1)
 #define PBSYS_CONFIG_STORAGE                        (1)
 #define PBSYS_CONFIG_STORAGE_NUM_SLOTS              (1)
diff --git a/lib/pbio/platform/nxt/pbsysconfig.h b/lib/pbio/platform/nxt/pbsysconfig.h
@@ -7,6 +7,7 @@
 #define PBSYS_CONFIG_FEATURE_PROGRAM_FORMAT_MULTI_MPY_V6           (1)
 #define PBSYS_CONFIG_FEATURE_PROGRAM_FORMAT_MULTI_MPY_V6_3_NATIVE  (0)
 #define PBSYS_CONFIG_HOST                           (1)
+#define PBSYS_CONFIG_HOST_STDIN_BUF_SIZE            (64)
 #define PBSYS_CONFIG_MAIN                           (1)
 #define PBSYS_CONFIG_STORAGE                        (1)
 #define PBSYS_CONFIG_STORAGE_NUM_SLOTS              (1)
diff --git a/lib/pbio/platform/prime_hub/pbsysconfig.h b/lib/pbio/platform/prime_hub/pbsysconfig.h
@@ -13,6 +13,7 @@
 #define PBSYS_CONFIG_HMI_NUM_SLOTS                  (5)
 #define PBSYS_CONFIG_HUB_LIGHT_MATRIX               (1)
 #define PBSYS_CONFIG_HOST                           (1)
+#define PBSYS_CONFIG_HOST_STDIN_BUF_SIZE            (64)
 #define PBSYS_CONFIG_MAIN                           (1)
 #define PBSYS_CONFIG_STORAGE                        (1)
 #define PBSYS_CONFIG_STORAGE_NUM_SLOTS              (5)
diff --git a/lib/pbio/platform/technic_hub/pbsysconfig.h b/lib/pbio/platform/technic_hub/pbsysconfig.h
@@ -13,6 +13,7 @@
 #define PBSYS_CONFIG_HMI_NUM_SLOTS                  (0)
 #define PBSYS_CONFIG_HUB_LIGHT_MATRIX               (0)
 #define PBSYS_CONFIG_HOST                           (1)
+#define PBSYS_CONFIG_HOST_STDIN_BUF_SIZE            (21)
 #define PBSYS_CONFIG_MAIN                           (1)
 #define PBSYS_CONFIG_STORAGE                        (1)
 #define PBSYS_CONFIG_STORAGE_NUM_SLOTS              (1)
diff --git a/lib/pbio/platform/test/pbsysconfig.h b/lib/pbio/platform/test/pbsysconfig.h
@@ -8,6 +8,7 @@
 #define PBSYS_CONFIG_FEATURE_PROGRAM_FORMAT_MULTI_MPY_V6_3_NATIVE  (0)
 #define PBSYS_CONFIG_BLUETOOTH                      (1)
 #define PBSYS_CONFIG_HOST                           (1)
+#define PBSYS_CONFIG_HOST_STDIN_BUF_SIZE            (64)
 #define PBSYS_CONFIG_HMI_NUM_SLOTS                  (0)
 #define PBSYS_CONFIG_HUB_LIGHT_MATRIX               (0)
 #define PBSYS_CONFIG_MAIN                           (0)
diff --git a/lib/pbio/sys/bluetooth.c b/lib/pbio/sys/bluetooth.c
@@ -28,10 +28,7 @@
 // REVISIT: this can be the negotiated MTU - 3 to allow for better throughput
 #define MAX_CHAR_SIZE 20
 
-// REVISIT: this needs to be moved to a common place where it can be shared with USB
-static pbsys_host_stdin_event_callback_t stdin_event_callback;
 static lwrb_t stdout_ring_buf;
-static lwrb_t stdin_ring_buf;
 
 typedef struct {
     list_t queue;
@@ -57,98 +54,14 @@ void pbsys_bluetooth_init(void) {
     // enough for two packets, one currently being sent and one to be ready
     // as soon as the previous one completes + 1 byte for ring buf pointer
     static uint8_t stdout_buf[MAX_CHAR_SIZE * 2 + 1];
-    // enough for one packet received + 1 byte for ring buf pointer
-    static uint8_t stdin_buf[PBDRV_BLUETOOTH_MAX_MTU_SIZE - 3 + 1];
 
     lwrb_init(&stdout_ring_buf, stdout_buf, PBIO_ARRAY_SIZE(stdout_buf));
-    lwrb_init(&stdin_ring_buf, stdin_buf, PBIO_ARRAY_SIZE(stdin_buf));
 
     process_start(&pbsys_bluetooth_process);
 }
 
-/**
- * Gets the number of bytes currently free for writing in stdin.
- * @return              The number of bytes.
- */
-uint32_t pbsys_bluetooth_rx_get_free(void) {
-    return lwrb_get_free(&stdin_ring_buf);
-}
-
-/**
- * Writes data to the stdin buffer.
- *
- * This does not currently return the number of bytes written, so first call
- * pbsys_bluetooth_rx_get_free() to ensure enough free space.
- *
- * @param [in]  data    The data to write to the stdin buffer.
- * @param [in]  size    The size of @p data in bytes.
- */
-void pbsys_bluetooth_rx_write(const uint8_t *data, uint32_t size) {
-    if (stdin_event_callback) {
-        // If there is a callback hook, we have to process things one byte at
-        // a time.
-        for (uint32_t i = 0; i < size; i++) {
-            if (!stdin_event_callback(data[i])) {
-                lwrb_write(&stdin_ring_buf, &data[i], 1);
-            }
-        }
-    } else {
-        lwrb_write(&stdin_ring_buf, data, size);
-    }
-}
-
 // Public API
 
-/**
- * Sets the UART Rx callback function.
- * @param callback  [in]    The callback or NULL.
- */
-void pbsys_bluetooth_rx_set_callback(pbsys_host_stdin_event_callback_t callback) {
-    stdin_event_callback = callback;
-}
-
-/**
- * Gets the number of bytes currently available to be read from the UART Rx
- * characteristic.
- * @return              The number of bytes.
- */
-uint32_t pbsys_bluetooth_rx_get_available(void) {
-    return lwrb_get_full(&stdin_ring_buf);
-}
-
-/**
- * Reads data from the stdin buffer.
- * @param data  [in]        A buffer to receive a copy of the data.
- * @param size  [in, out]   The number of bytes to read (@p data must be at least
- *                          this big). After return @p size contains the number
- *                          of bytes actually read.
- * @return                  ::PBIO_SUCCESS if @p data was read, ::PBIO_ERROR_AGAIN
- *                          if @p data could not be read at this time (i.e. buffer
- *                          is empty), ::PBIO_ERROR_INVALID_OP if there is not an
- *                          active Bluetooth connection or ::PBIO_ERROR_NOT_SUPPORTED
- *                          if this platform does not support Bluetooth.
- */
-pbio_error_t pbsys_bluetooth_rx(uint8_t *data, uint32_t *size) {
-    // make sure we have a Bluetooth connection
-    if (!pbdrv_bluetooth_is_connected(PBDRV_BLUETOOTH_CONNECTION_PYBRICKS)) {
-        return PBIO_ERROR_INVALID_OP;
-    }
-
-    if ((*size = lwrb_read(&stdin_ring_buf, data, *size)) == 0) {
-        return PBIO_ERROR_AGAIN;
-    }
-
-    return PBIO_SUCCESS;
-}
-
-/**
- * Flushes data from the UART Rx characteristic so that ::pbsys_bluetooth_rx
- * can be used to wait for new data.
- */
-void pbsys_bluetooth_rx_flush(void) {
-    lwrb_reset(&stdin_ring_buf);
-}
-
 /**
  * Queues data to be transmitted via Bluetooth serial port.
  * @param data  [in]        The data to be sent.
@@ -247,7 +160,6 @@ static void reset_all(void) {
 
     send_busy = false;
 
-    lwrb_reset(&stdin_ring_buf);
     lwrb_reset(&stdout_ring_buf);
 }
 
diff --git a/lib/pbio/sys/bluetooth.h b/lib/pbio/sys/bluetooth.h
@@ -10,30 +10,18 @@
 #include <pbio/error.h>
 #include <pbsys/host.h>
 
-uint32_t pbsys_bluetooth_rx_get_free(void);
-void pbsys_bluetooth_rx_write(const uint8_t *data, uint32_t size);
 void pbsys_bluetooth_process_poll(void);
 
 #if PBSYS_CONFIG_BLUETOOTH
 
 void pbsys_bluetooth_init(void);
-void pbsys_bluetooth_rx_set_callback(pbsys_host_stdin_event_callback_t callback);
-void pbsys_bluetooth_rx_flush(void);
-uint32_t pbsys_bluetooth_rx_get_available(void);
-pbio_error_t pbsys_bluetooth_rx(uint8_t *data, uint32_t *size);
 pbio_error_t pbsys_bluetooth_tx(const uint8_t *data, uint32_t *size);
 bool pbsys_bluetooth_tx_is_idle(void);
 
 #else // PBSYS_CONFIG_BLUETOOTH
 
 #define pbsys_bluetooth_init()
-#define pbsys_bluetooth_rx_set_callback(callback)
-#define pbsys_bluetooth_rx_flush()
-#define pbsys_bluetooth_rx_get_available() 0
 
-static inline pbio_error_t pbsys_bluetooth_rx(uint8_t *data, uint32_t *size) {
-    return PBIO_ERROR_NOT_SUPPORTED;
-}
 static inline pbio_error_t pbsys_bluetooth_tx(const uint8_t *data, uint32_t *size) {
     return PBIO_ERROR_NOT_SUPPORTED;
 }
diff --git a/lib/pbio/sys/command.c b/lib/pbio/sys/command.c
@@ -73,10 +73,10 @@ pbio_pybricks_error_t pbsys_command(const uint8_t *data, uint32_t size) {
 
         case PBIO_PYBRICKS_COMMAND_WRITE_STDIN:
             #if PBSYS_CONFIG_HOST
-            if (pbsys_host_rx_get_free() < size - 1) {
+            if (pbsys_host_stdin_get_free() < size - 1) {
                 return PBIO_PYBRICKS_ERROR_BUSY;
             }
-            pbsys_host_rx_write(&data[1], size - 1);
+            pbsys_host_stdin_write(&data[1], size - 1);
             #endif
             // If no consumers are configured, goes to "/dev/null" without error
             return PBIO_PYBRICKS_ERROR_OK;
diff --git a/lib/pbio/sys/host.c b/lib/pbio/sys/host.c
diff --git a/lib/pbio/sys/main.c b/lib/pbio/sys/main.c
diff --git a/lib/pbio/test/sys/test_bluetooth.c b/lib/pbio/test/sys/test_bluetooth.c

Original file line number	Diff line number	Diff line change
`@@ -38,7 +38,7 @@ void mp_hal_delay_ms(mp_uint_t Delay) {`
`38`	`38`	`uintptr_t mp_hal_stdio_poll(uintptr_t poll_flags) {`
`39`	`39`	`uintptr_t ret = 0;`
`40`	`40`
`41`		`- if ((poll_flags & MP_STREAM_POLL_RD) && pbsys_host_rx_get_available()) {`
	`41`	`+ if ((poll_flags & MP_STREAM_POLL_RD) && pbsys_host_stdin_get_available()) {`
`42`	`42`	`ret \|= MP_STREAM_POLL_RD;`
`43`	`43`	`}`
`44`	`44`
`@@ -51,7 +51,7 @@ int mp_hal_stdin_rx_chr(void) {`
`51`	`51`	`uint8_t c;`
`52`	`52`
`53`	`53`	`// wait for rx interrupt`
`54`		`- while (size = 1, pbsys_host_rx(&c, &size) != PBIO_SUCCESS) {`
	`54`	`+ while (size = 1, pbsys_host_stdin_read(&c, &size) != PBIO_SUCCESS) {`
`55`	`55`	`MICROPY_EVENT_POLL_HOOK`
`56`	`56`	`}`
`57`	`57`