pbio/drv/uart: Refactor async read and write

lib/pbio/drv/adc/adc.h

@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: MIT
+// Copyright (c) 2024 The Pybricks Authors
+
+// Internal common adc functions.
+
+#ifndef _INTERNAL_PBDRV_ADC_H_
+#define _INTERNAL_PBDRV_ADC_H_
+
+#include <pbdrv/config.h>
+
+#if PBDRV_CONFIG_ADC
+
+void pbdrv_adc_init(void);
+
+#else // PBDRV_CONFIG_ADC
+
+#define pbdrv_adc_init()
+
+#endif // PBDRV_CONFIG_ADC
+
+#endif // _INTERNAL_PBDRV_ADC_H_

lib/pbio/drv/adc/adc_stm32_hal.c

@@ -81,11 +81,7 @@ static void pbdrv_adc_exit(void) {
     HAL_DMA_DeInit(&pbdrv_adc_hdma);
 }
 
-PROCESS_THREAD(pbdrv_adc_process, ev, data) {
-    PROCESS_POLLHANDLER(pbdrv_adc_poll());
-    PROCESS_EXITHANDLER(pbdrv_adc_exit());
-
-    PROCESS_BEGIN();
+void pbdrv_adc_init(void) {
 
     // Timer to trigger ADC
 
@@ -149,6 +145,15 @@ PROCESS_THREAD(pbdrv_adc_process, ev, data) {
     HAL_ADC_Start_DMA(&pbdrv_adc_hadc, pbdrv_adc_dma_buffer, PBIO_ARRAY_SIZE(pbdrv_adc_dma_buffer));
     HAL_TIM_Base_Start(&pbdrv_adc_htim);
 
+    process_start(&pbdrv_adc_process);
+}
+
+PROCESS_THREAD(pbdrv_adc_process, ev, data) {
+    PROCESS_POLLHANDLER(pbdrv_adc_poll());
+    PROCESS_EXITHANDLER(pbdrv_adc_exit());
+
+    PROCESS_BEGIN();
+
     while (true) {
         PROCESS_WAIT_EVENT();
     }

lib/pbio/drv/adc/adc_stm32f0.c

@@ -35,7 +35,7 @@ static void pbdrv_adc_calibrate(void) {
     }
 }
 
-static void pbdrv_adc_init(void) {
+void pbdrv_adc_init(void) {
     // enable power domain
     RCC->APB2ENR |= RCC_APB2ENR_ADCEN;
 
@@ -61,6 +61,8 @@ static void pbdrv_adc_init(void) {
     // TODO: LEGO firmware reads CH 3 during init 10 times and averages it.
     // Not sure what this is measuring or what it would be used for. Perhaps
     // some kind of ID resistor?
+
+    process_start(&pbdrv_adc_process);
 }
 
 // does a single conversion for the specified channel
@@ -91,8 +93,6 @@ PROCESS_THREAD(pbdrv_adc_process, ev, data) {
 
     PROCESS_BEGIN();
 
-    pbdrv_adc_init();
-
     while (true) {
         PROCESS_WAIT_EVENT();
     }

lib/pbio/drv/bluetooth/bluetooth_btstack.c

@@ -40,8 +40,7 @@
 #endif
 
 #if 0
-#include <pbdrv/../../drv/ioport/ioport_debug_uart.h>
-#define DEBUG_PRINT pbdrv_ioport_debug_uart_printf
+#define DEBUG_PRINT(...)
 #else
 #define DEBUG_PRINT(...)
 #endif

lib/pbio/drv/bluetooth/bluetooth_stm32_cc2640.c

@@ -43,26 +43,22 @@
 
 #include "./bluetooth_stm32_cc2640.h"
 
-#define DEBUG_LL (0x01)
-#define DEBUG_PT (0x02)
+PROCESS(pbdrv_bluetooth_spi_process, "Bluetooth SPI");
 
-// Choose either/or DEBUG_LL | DEBUG_PT
-#define DEBUG (0)
+#define DEBUG_ON_LAST_UART_PORT (0)
 
-#if DEBUG
+#if DEBUG_ON_LAST_UART_PORT
 #include <pbdrv/../../drv/ioport/ioport_debug_uart.h>
-#endif
-#if (DEBUG & DEBUG_LL)
-#define DBG pbdrv_ioport_debug_uart_printf
-#else
 #define DBG(...)
-#endif
-#if (DEBUG & DEBUG_PT)
-#define DEBUG_PRINT pbdrv_ioport_debug_uart_printf
+#define DEBUG_PRINT(...)
 #define DEBUG_PRINT_PT PBDRV_IOPORT_DEBUG_UART_PT_PRINTF
+static void uart_poll_callback(pbdrv_uart_dev_t *uart) {
+    process_poll(&pbdrv_bluetooth_spi_process);
+}
 #else
-#define DEBUG_PRINT_PT(...)
+#define DBG(...)
 #define DEBUG_PRINT(...)
+#define DEBUG_PRINT_PT(...)
 #endif
 
 // hub name goes in special section so that it can be modified when flashing firmware
@@ -156,8 +152,6 @@ static uint16_t uart_service_handle, uart_service_end_handle, uart_rx_char_handl
 // Nordic UART tx notifications enabled
 static bool uart_tx_notify_en;
 
-PROCESS(pbdrv_bluetooth_spi_process, "Bluetooth SPI");
-
 LIST(task_queue);
 static bool bluetooth_ready;
 static pbdrv_bluetooth_on_event_t bluetooth_on_event;
@@ -2277,6 +2271,14 @@ PROCESS_THREAD(pbdrv_bluetooth_spi_process, ev, data) {
 
     PROCESS_BEGIN();
 
+    #if DEBUG_ON_LAST_UART_PORT
+    // Wait for the UART to be ready for debugging.
+    while (pbdrv_ioport_debug_uart_init(uart_poll_callback) != PBIO_SUCCESS) {
+        etimer_set(&timer, 100);
+        PROCESS_WAIT_EVENT_UNTIL(ev == PROCESS_EVENT_TIMER && etimer_expired(&timer));
+    }
+    #endif // DEBUG_ON_LAST_UART_PORT
+
 start:
     // take Bluetooth chip out of reset
     bluetooth_reset(RESET_STATE_OUT_HIGH);

lib/pbio/drv/core.c

@@ -6,6 +6,7 @@
 #include <pbdrv/config.h>
 
 #include "core.h"
+#include "adc/adc.h"
 #include "battery/battery.h"
 #include "block_device/block_device.h"
 #include "bluetooth/bluetooth.h"
@@ -38,6 +39,7 @@ void pbdrv_init(void) {
     process_start(&etimer_process);
 
     // the rest of the drivers should be implemented so that init order doesn't matter
+    pbdrv_adc_init();
     pbdrv_battery_init();
     pbdrv_block_device_init();
     pbdrv_bluetooth_init();

lib/pbio/drv/ioport/ioport_debug_uart.c

@@ -20,16 +20,13 @@
 #error "PBDRV_CONFIG_IOPORT_DEBUG_UART requires exactly one port"
 #endif
 
-static char buffer[64];
-static pbdrv_uart_dev_t *debug_uart;
+// Use globals for simplified debug macro inside protothreads.
+struct pt debug_printf_thread;
+char debug_buffer[64];
+pbdrv_uart_dev_t *debug_uart;
+pbio_error_t debug_err;
 
-#define UART_TIMEOUT (250)
-
-static pbio_error_t pbdrv_ioport_init(void) {
-    // UART already initialized.
-    if (debug_uart) {
-        return PBIO_SUCCESS;
-    }
+pbio_error_t pbdrv_ioport_debug_uart_init(pbdrv_uart_poll_callback_t callback) {
 
     // Get the debug uart from last port.
     const pbdrv_ioport_pup_port_platform_data_t *port_data = &pbdrv_ioport_pup_platform_data.ports[PBDRV_CONFIG_IOPORT_NUM_DEV - 1];
@@ -39,6 +36,8 @@ static pbio_error_t pbdrv_ioport_init(void) {
         return err;
     }
 
+    pbdrv_uart_set_poll_callback(debug_uart, callback);
+
     // Enable and configure uart.
     const pbdrv_ioport_pup_pins_t *pins = &port_data->pins;
     pbdrv_gpio_alt(&pins->uart_rx, pins->uart_alt);
@@ -50,60 +49,11 @@ static pbio_error_t pbdrv_ioport_init(void) {
     return PBIO_SUCCESS;
 }
 
-pbio_error_t pbdrv_ioport_debug_uart_printf(const char *format, ...) {
-
-    // Get the debug uart.
-    pbio_error_t err = pbdrv_ioport_init();
-    if (err != PBIO_SUCCESS) {
-        return err;
-    }
-
-    // If still writing, just ignore this debug message.
-    err = pbdrv_uart_write_end(debug_uart);
-    if (err != PBIO_SUCCESS) {
-        return err;
-    }
-
-    // Buffer result.
+void pbdrv_ioport_debug_uart_printf_buffer(const char *format, ...) {
     va_list args;
     va_start(args, format);
-    vsnprintf(buffer, sizeof(buffer), format, args);
+    vsnprintf(debug_buffer, sizeof(debug_buffer), format, args);
     va_end(args);
-
-    // Write to uart.
-    return pbdrv_uart_write_begin(debug_uart, (uint8_t *)buffer, strlen(buffer), UART_TIMEOUT);
-}
-
-// Protothread set up here for simplified debug macro inside protothreads.
-struct pt printf_thread;
-
-PT_THREAD(pbdrv_ioport_debug_uart_printf_thread(struct pt *pt, const char *format, ...)) {
-    static pbio_error_t err;
-
-    PT_BEGIN(pt);
-
-    // Only print if port initialized.
-    err = pbdrv_ioport_init();
-    if (err != PBIO_SUCCESS) {
-        PT_EXIT(pt);
-    }
-
-    // Buffer result.
-    va_list args;
-    va_start(args, format);
-    vsnprintf(buffer, sizeof(buffer), format, args);
-    va_end(args);
-
-    // Wait for uart to be ready then write.
-    PT_WAIT_UNTIL((pt), (err = pbdrv_uart_write_begin(debug_uart, (uint8_t *)buffer, strlen(buffer), UART_TIMEOUT)) != PBIO_ERROR_AGAIN);
-    if (err != PBIO_SUCCESS) {
-        PT_EXIT(pt);
-    }
-
-    // Wait for uart to finish.
-    PT_WAIT_UNTIL((pt), (err = pbdrv_uart_write_end(debug_uart)) != PBIO_ERROR_AGAIN);
-
-    PT_END(pt);
 }
 
 #endif // PBDRV_CONFIG_IOPORT_DEBUG_UART

lib/pbio/drv/ioport/ioport_debug_uart.h

@@ -9,28 +9,18 @@
 #include <pbio/error.h>
 
 #include <pbdrv/config.h>
+#include <pbdrv/uart.h>
 
 #if PBDRV_CONFIG_IOPORT_DEBUG_UART
 
-extern struct pt printf_thread;
+extern char debug_buffer[];
+extern struct pt debug_printf_thread;
+extern pbdrv_uart_dev_t *debug_uart;
+extern pbio_error_t debug_err;
 
-/**
- * Prints debug information on the last ioport.
- *
- * Will not print anything if the debug uart is already in use by another
- * debug message, to avoid blocking.
- *
- * Useful outside of a protothread or when timing is more critical while
- * complete information is not.
- *
- * @param [in]  format  Format string.
- * @param [in]  ...     Arguments.
- *
- * @return Error code.
- */
-pbio_error_t pbdrv_ioport_debug_uart_printf(const char *format, ...);
+PT_THREAD(pbdrv_ioport_debug_uart_debug_printf_thread(struct pt *pt, const char *format, ...));
 
-PT_THREAD(pbdrv_ioport_debug_uart_printf_thread(struct pt *pt, const char *format, ...));
+void pbdrv_ioport_debug_uart_printf_buffer(const char *format, ...);
 
 /**
  * Spawns a task to print debug information on the last ioport.
@@ -42,13 +32,14 @@ PT_THREAD(pbdrv_ioport_debug_uart_printf_thread(struct pt *pt, const char *forma
  * @param [in]  ...    Format string and arguments.
  */
 #define PBDRV_IOPORT_DEBUG_UART_PT_PRINTF(pt, ...) \
-    PT_SPAWN(pt, &printf_thread, pbdrv_ioport_debug_uart_printf_thread(&printf_thread, __VA_ARGS__))
+    pbdrv_ioport_debug_uart_printf_buffer(__VA_ARGS__); \
+    if (debug_uart) { \
+        PT_SPAWN(pt, &debug_printf_thread, pbdrv_uart_write(&debug_printf_thread, debug_uart, (uint8_t *)debug_buffer, strlen(debug_buffer), 250, &debug_err)); \
+    } \
 
-#else // PBDRV_CONFIG_IOPORT_DEBUG_UART
+pbio_error_t pbdrv_ioport_debug_uart_init(pbdrv_uart_poll_callback_t callback);
 
-static inline pbio_error_t pbdrv_ioport_debug_uart_printf(const char *format, ...) {
-    return PBIO_ERROR_NOT_SUPPORTED;
-}
+#else // PBDRV_CONFIG_IOPORT_DEBUG_UART
 
 #define PBDRV_IOPORT_DEBUG_UART_PT_PRINTF(pt, ...)
 

lib/pbio/drv/legodev/legodev_pup.c

@@ -14,6 +14,7 @@
 #include <contiki.h>
 
 #include <pbdrv/gpio.h>
+#include <pbdrv/uart.h>
 
 #include <pbsys/status.h>
 
@@ -107,6 +108,11 @@ static void legodev_pup_enable_uart(const pbdrv_ioport_pup_pins_t *pins) {
     pbdrv_gpio_out_low(&pins->uart_buf);
 }
 
+static void legodev_pup_disable_uart(const pbdrv_ioport_pup_pins_t *pins) {
+    // REVISIT: Move to ioport.
+    pbdrv_gpio_out_high(&pins->uart_buf);
+}
+
 // This is the device connection manager (dcm). It monitors the ID1 and ID2 pins
 // on the port to see when devices are connected or disconnected.
 // It is expected for there to be a 2ms delay between calls to this function.
@@ -343,6 +349,7 @@ static PT_THREAD(pbdrv_legodev_pup_thread(ext_dev_t * dev)) {
     while (true) {
 
         // Initially assume nothing is connected.
+        legodev_pup_disable_uart(dev->pins);
         dev->dcm.connected_type_id = PBDRV_LEGODEV_TYPE_ID_NONE;
         dev->dcm.dev_id_match_count = 0;
 
@@ -369,6 +376,7 @@ static PT_THREAD(pbdrv_legodev_pup_thread(ext_dev_t * dev)) {
         // disconnects, as observed by the UART process not getting valid data.
         legodev_pup_enable_uart(dev->pins);
         PT_SPAWN(&dev->pt, &dev->child, pbdrv_legodev_pup_uart_thread(&dev->child, dev->uart_dev));
+
     }
     PT_END(&dev->pt);
 }
@@ -405,6 +413,14 @@ PROCESS_THREAD(pbio_legodev_pup_process, ev, data) {
     PROCESS_END();
 }
 
+/**
+ * We get notified when the uart driver has completed sending or receiving data.
+ */
+static void uart_poll_callback(pbdrv_uart_dev_t *uart) {
+    // REVISIT: Only need to poll the specified uart device.
+    process_poll(&pbio_legodev_pup_process);
+}
+
 void pbdrv_legodev_init(void) {
     #if PBDRV_CONFIG_LEGODEV_PUP_NUM_INT_DEV > 0
     for (uint8_t i = 0; i < PBDRV_CONFIG_LEGODEV_PUP_NUM_INT_DEV; i++) {
@@ -431,7 +447,15 @@ void pbdrv_legodev_init(void) {
         pbio_dcmotor_get_dcmotor(legodev, &dcmotor);
         legodev->ext_dev->uart_dev = pbdrv_legodev_pup_uart_configure(legodev_data->ioport_index, port_data->uart_driver_index, dcmotor);
 
+        // legodev driver is started after all other drivers, so we
+        // assume that we do not need to wait for this to be ready.
+        pbdrv_uart_dev_t *uart;
+        pbdrv_uart_get(port_data->uart_driver_index, &uart);
+
+        // Set callback for uart driver.
+        pbdrv_uart_set_poll_callback(uart, uart_poll_callback);
     }
+
     process_start(&pbio_legodev_pup_process);
 }