Bidirectional DShot

Co-authored-by: Julian Oes <[email protected]>

Author: dakejahl

platforms/nuttx/src/px4/rpi/rpi_common/include/px4_arch/io_timer.h

@@ -147,9 +147,6 @@ __EXPORT int io_timer_free_channel(unsigned channel);
 __EXPORT int io_timer_get_channel_mode(unsigned channel);
 __EXPORT int io_timer_get_mode_channels(io_timer_channel_mode_t mode);
 __EXPORT extern void io_timer_trigger(void);
-__EXPORT void io_timer_update_dma_req(uint8_t timer, bool enable);
-
-__EXPORT extern int io_timer_set_dshot_mode(uint8_t timer, unsigned dshot_pwm_rate, uint8_t dma_burst_length);
 
 /**
  * Returns the pin configuration for a specific channel, to be used as GPIO output.

platforms/nuttx/src/px4/stm/stm32_common/dshot/CMakeLists.txt

@@ -34,4 +34,5 @@
 px4_add_library(arch_dshot
 	dshot.c
 )
+# target_compile_options(arch_dshot PRIVATE ${MAX_CUSTOM_OPT_LEVEL} -DDEBUG_BUILD)
 target_compile_options(arch_dshot PRIVATE ${MAX_CUSTOM_OPT_LEVEL})

platforms/nuttx/src/px4/stm/stm32_common/dshot/dshot.c

@@ -1,6 +1,6 @@
 /****************************************************************************
  *
- * Copyright (C) 2019 PX4 Development Team. All rights reserved.
+ * Copyright (C) 2024 PX4 Development Team. All rights reserved.
  * Author: Igor Misic <[email protected]>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -58,5 +58,6 @@
  */
 typedef struct dshot_conf_t {
 	uint32_t			dma_base;
-	uint32_t			dmamap;
+	uint32_t			dma_map_up;
+	uint32_t			dma_map_ch[4];
 } dshot_conf_t;

platforms/nuttx/src/px4/stm/stm32_common/include/px4_arch/dshot.h

@@ -1,6 +1,6 @@
 /****************************************************************************
  *
- *   Copyright (C) 2012, 2017 PX4 Development Team. All rights reserved.
+ *   Copyright (C) 2024 PX4 Development Team. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -80,6 +80,8 @@ typedef enum io_timer_channel_mode_t {
 	IOTimerChanMode_LED     = 7,
 	IOTimerChanMode_PPS     = 8,
 	IOTimerChanMode_Other   = 9,
+	IOTimerChanMode_DshotInverted = 10,
+	IOTimerChanMode_CaptureDMA = 11,
 	IOTimerChanModeSize
 } io_timer_channel_mode_t;
 
@@ -158,7 +160,12 @@ __EXPORT int io_timer_unallocate_channel(unsigned channel);
 __EXPORT int io_timer_get_channel_mode(unsigned channel);
 __EXPORT int io_timer_get_mode_channels(io_timer_channel_mode_t mode);
 __EXPORT extern void io_timer_trigger(unsigned channels_mask);
+
 __EXPORT void io_timer_update_dma_req(uint8_t timer, bool enable);
+__EXPORT int io_timer_set_dshot_burst_mode(uint8_t timer, unsigned dshot_pwm_rate, uint8_t dma_burst_length);
+
+__EXPORT void io_timer_capture_dma_req(uint8_t timer, uint8_t timer_channel_index, bool enable);
+__EXPORT int io_timer_set_dshot_capture_mode(uint8_t timer, uint8_t timer_channel_index, unsigned dshot_pwm_freq);
 
 /**
  * Reserve a timer
@@ -168,7 +175,6 @@ __EXPORT int io_timer_allocate_timer(unsigned timer, io_timer_channel_mode_t mod
 
 __EXPORT int io_timer_unallocate_timer(unsigned timer);
 
-__EXPORT extern int io_timer_set_dshot_mode(uint8_t timer, unsigned dshot_pwm_rate, uint8_t dma_burst_length);
 
 /**
  * Returns the pin configuration for a specific channel, to be used as GPIO output.

platforms/nuttx/src/px4/stm/stm32_common/include/px4_arch/io_timer.h

@@ -1,6 +1,6 @@
 /****************************************************************************
  *
- *   Copyright (C) 2019 PX4 Development Team. All rights reserved.
+ *   Copyright (C) 2024 PX4 Development Team. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -103,7 +103,7 @@ static inline constexpr timer_io_channels_t initIOTimerChannelOutputClear(const
 }
 
 
-static inline constexpr io_timers_t initIOTimer(Timer::Timer timer, DMA dshot_dma = {})
+static inline constexpr io_timers_t initIOTimer(Timer::Timer timer, DMA dma = {})
 {
 	bool nuttx_config_timer_enabled = false;
 	io_timers_t ret{};
@@ -268,9 +268,10 @@ static inline constexpr io_timers_t initIOTimer(Timer::Timer timer, DMA dshot_dm
 	constexpr_assert(!nuttx_config_timer_enabled, "IO Timer requires NuttX timer config to be disabled (STM32_TIMx)");
 
 	// DShot
-	if (dshot_dma.index != DMA::Invalid) {
-		ret.dshot.dma_base = getDMABaseRegister(dshot_dma);
-		ret.dshot.dmamap = getTimerUpdateDMAMap(timer, dshot_dma);
+	if (dma.index != DMA::Invalid) {
+		ret.dshot.dma_base = getDMABaseRegister(dma);
+		ret.dshot.dma_map_up = getTimerUpdateDMAMap(timer, dma);
+		getTimerChannelDMAMap(timer, dma, ret.dshot.dma_map_ch);
 	}
 
 	return ret;

platforms/nuttx/src/px4/stm/stm32_common/include/px4_arch/io_timer_hw_description.h

@@ -1,6 +1,6 @@
 /****************************************************************************
  *
- *   Copyright (C) 2012-2016 PX4 Development Team. All rights reserved.
+ *   Copyright (C) 2024 PX4 Development Team. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -365,8 +365,10 @@ int up_input_capture_set_trigger(unsigned channel,  input_capture_edge edge)
 		rv = -ENXIO;
 
 		/* Any pins in capture mode */
+		int mode = io_timer_get_channel_mode(channel);
 
-		if (io_timer_get_channel_mode(channel) == IOTimerChanMode_Capture) {
+		if (mode == IOTimerChanMode_Capture ||
+		    mode == IOTimerChanMode_CaptureDMA) {
 
 			uint16_t edge_bits = 0xffff;