rp2xxx.h

 
#pragma once
 
#include <hardware/pio.h>
#include <pico/time.h>
 
#include <joybus/bus.h>

#define JOYBUS_RP2XXX(bus) ((struct joybus_rp2xxx *)(bus))
 
// Private implementation details - do not access directly
struct joybus_rp2xxx_data {
  // Bus state
  uint8_t state;
 
  // GPIO configuration
  uint gpio;
 
  // PIO instance and state machine
  PIO pio;
  uint pio_sm;
  bool pio_configured;
 
  // DMA configuration
  uint dma_chan_tx;
  uint dma_chan_rx;
 
  // RX/TX state
  uint8_t *read_buf;
  uint8_t read_len;
  uint8_t read_count;
  uint8_t *write_buf;
  uint8_t write_len;
  alarm_id_t rx_timeout_alarm;
 
  // Transfer state
  joybus_transfer_cb done_callback;
  void *done_user_data;
  absolute_time_t last_transfer_time;
  alarm_id_t transfer_start_alarm;
};

struct joybus_rp2xxx {
  struct joybus base;
  struct joybus_rp2xxx_data data;
};

struct joybus_rp2xxx_config {
  uint8_t gpio;

  PIO pio;

  uint32_t freq;
};

static inline struct joybus_rp2xxx_config joybus_rp2xxx_config_default(uint8_t gpio)
{
  return (struct joybus_rp2xxx_config){
    .gpio = gpio,
    .pio  = pio0,
    .freq = JOYBUS_FREQ_NOMINAL,
  };
}

int joybus_rp2xxx_init(struct joybus_rp2xxx *rp2xxx_bus, struct joybus_rp2xxx_config config);