AP_HAL_SITL: simulated i2c support

libraries/AP_HAL_SITL/AP_HAL_SITL_Namespace.h

@@ -6,6 +6,8 @@ class Scheduler;
 class SITL_State;
 class Storage;
 class AnalogIn;
+class I2CDevice;
+class I2CDeviceManager;
 class RCInput;
 class RCOutput;
 class ADCSource;

libraries/AP_HAL_SITL/HAL_SITL_Class.cpp

@@ -13,6 +13,7 @@
 #include "Scheduler.h"
 #include "AnalogIn.h"
 #include "UARTDriver.h"
+#include "I2CDevice.h"
 #include "Storage.h"
 #include "RCInput.h"
 #include "RCOutput.h"
@@ -40,7 +41,6 @@ static DSP dspDriver;
 
 
 // use the Empty HAL for hardware we don't emulate
-static Empty::I2CDeviceManager i2c_mgr_instance;
 static Empty::SPIDeviceManager emptySPI;
 static Empty::OpticalFlow emptyOpticalFlow;
 static Empty::Flash emptyFlash;
@@ -54,6 +54,8 @@ static UARTDriver sitlUart5Driver(5, &sitlState);
 static UARTDriver sitlUart6Driver(6, &sitlState);
 static UARTDriver sitlUart7Driver(7, &sitlState);
 
+static I2CDeviceManager i2c_mgr_instance;
+
 static Util utilInstance(&sitlState);
 
 HAL_SITL::HAL_SITL() :

libraries/AP_HAL_SITL/I2CDevice.cpp

@@ -0,0 +1,204 @@
+/*
+ * Copyright (C) 2020  Peter Barker. All rights reserved.
+ *
+ * This file is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "I2CDevice.h"
+
+#include <AP_HAL/AP_HAL.h>
+#include <SITL/SITL.h>
+
+extern const AP_HAL::HAL& hal;
+
+using namespace HALSITL;
+
+/*
+ * I2CBus
+ */
+class I2CBus {
+    friend class I2CDeviceManager;
+public:
+    uint8_t bus;
+    Semaphore sem;
+    int ioctl(uint8_t ioctl_number, void *data) {
+        return _ioctl(ioctl_number, data);
+    }
+    void _timer_tick(); // in lieu of a thread-per-bus
+    AP_HAL::Device::PeriodicHandle register_periodic_callback(uint32_t period_usec, AP_HAL::Device::PeriodicCb cb);
+
+private:
+    int _ioctl(uint8_t ioctl_number, void *data);
+
+    struct callback_info {
+        struct callback_info *next;
+        AP_HAL::Device::PeriodicCb cb;
+        uint32_t period_usec;
+        uint64_t next_usec;
+    } *callbacks;
+};
+
+int I2CBus::_ioctl(uint8_t ioctl_number, void *data)
+{
+    SITL::SITL *sitl = AP::sitl();
+    return sitl->i2c_ioctl(ioctl_number, data);
+}
+
+AP_HAL::Device::PeriodicHandle I2CBus::register_periodic_callback(uint32_t period_usec, AP_HAL::Device::PeriodicCb cb)
+{
+    // mostly swiped from ChibiOS:
+    I2CBus::callback_info *callback = new I2CBus::callback_info;
+    if (callback == nullptr) {
+        return nullptr;
+    }
+    callback->cb = cb;
+    callback->period_usec = period_usec;
+    callback->next_usec = AP_HAL::micros64() + period_usec;
+
+    // add to linked list of callbacks on thread
+    callback->next = callbacks;
+    callbacks = callback;
+    return callback;
+}
+
+void I2CBus::_timer_tick()
+{
+    const uint64_t now = AP_HAL::micros64();
+    for (struct callback_info *ci = callbacks; ci != nullptr; ci = ci->next) {
+        if (ci->next_usec >= now) {
+            ci->cb();
+            ci->next_usec += ci->period_usec;
+        }
+    }
+}
+
+/*
+ * I2CDeviceManager
+ */
+
+I2CBus I2CDeviceManager::buses[NUM_SITL_I2C_BUSES];
+
+I2CDeviceManager::I2CDeviceManager()
+{
+}
+
+AP_HAL::OwnPtr<AP_HAL::I2CDevice>
+I2CDeviceManager::get_device(uint8_t bus,
+                             uint8_t address,
+                             uint32_t bus_clock,
+                             bool use_smbus,
+                             uint32_t timeout_ms)
+{
+    if (bus >= ARRAY_SIZE(buses)) {
+        return AP_HAL::OwnPtr<AP_HAL::I2CDevice>(nullptr);
+    }
+    auto dev = AP_HAL::OwnPtr<AP_HAL::I2CDevice>(new I2CDevice(buses[bus], address));
+    return dev;
+}
+
+void I2CDeviceManager::_timer_tick()
+{
+    for (auto bus : buses) {
+        bus._timer_tick();
+    }
+}
+
+/*
+ * I2CDevice
+ */
+
+I2CDevice::I2CDevice(I2CBus &bus, uint8_t address)
+    : _bus(bus)
+    , _address(address)
+{
+    set_device_bus(bus.bus);
+    set_device_address(address);
+}
+
+#include <stdio.h>
+
+#include <signal.h>
+
+bool I2CDevice::transfer(const uint8_t *send, uint32_t send_len,
+                         uint8_t *recv, uint32_t recv_len)
+{
+//    kill(0, SIGTRAP);
+    // combined transfer
+    if (!_transfer(send, send_len, recv, recv_len)) {
+        return false;
+    }
+    return true;
+}
+
+bool I2CDevice::_transfer(const uint8_t *send, uint32_t send_len,
+                          uint8_t *recv, uint32_t recv_len)
+{
+    struct i2c_msg msgs[2] = { };
+    unsigned nmsgs = 0;
+
+    if (send && send_len != 0) {
+        msgs[nmsgs].addr = _address;
+        msgs[nmsgs].flags = 0;
+        msgs[nmsgs].buf = const_cast<uint8_t*>(send);
+        msgs[nmsgs].len = send_len;
+        nmsgs++;
+    }
+
+    if (recv && recv_len != 0) {
+        msgs[nmsgs].addr = _address;
+        msgs[nmsgs].flags = I2C_M_RD;
+        msgs[nmsgs].buf = recv;
+        msgs[nmsgs].len = recv_len;
+        nmsgs++;
+    }
+
+    /* interpret it as an input error if nothing has to be done */
+    if (!nmsgs) {
+        return false;
+    }
+
+    struct i2c_rdwr_ioctl_data i2c_data = { };
+
+    i2c_data.msgs = msgs;
+    i2c_data.nmsgs = nmsgs;
+
+    int r;
+    unsigned retries = _retries;
+    do {
+        r = _bus.ioctl(I2C_RDWR, &i2c_data);
+    } while (r == -1 && retries-- > 0);
+
+    return r != -1;
+}
+
+bool I2CDevice::read_registers_multiple(uint8_t first_reg, uint8_t *recv,
+                                        uint32_t recv_len, uint8_t times)
+{
+    ::fprintf(stderr, "read_registers_multiple called\n");
+    return false;
+}
+
+AP_HAL::Semaphore *I2CDevice::get_semaphore() {
+    return &_bus.sem;
+}
+
+AP_HAL::Device::PeriodicHandle I2CDevice::register_periodic_callback(uint32_t period_usec, AP_HAL::Device::PeriodicCb cb)
+{
+    return _bus.register_periodic_callback(period_usec, cb);
+}
+
+bool I2CDevice::adjust_periodic_callback(Device::PeriodicHandle h, uint32_t period_usec)
+{
+    return false;
+}
+

libraries/AP_HAL_SITL/I2CDevice.h

@@ -0,0 +1,127 @@
+/*
+ * Copyright (C) 2020  Peter Barker. All rights reserved.
+ *
+ * This file is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include <inttypes.h>
+
+#include <AP_HAL/HAL.h>
+#include <AP_HAL/I2CDevice.h>
+#include <AP_HAL/utility/OwnPtr.h>
+
+#include "AP_HAL_SITL_Namespace.h"
+#include "Semaphores.h"
+
+class I2CBus;
+
+class HALSITL::I2CDevice : public AP_HAL::I2CDevice {
+public:
+    static I2CDevice *from(AP_HAL::I2CDevice *dev) {
+        return static_cast<I2CDevice*>(dev);
+    }
+
+    /* AP_HAL::I2CDevice implementation */
+
+    I2CDevice(I2CBus &bus, uint8_t address);
+
+    ~I2CDevice() {}
+
+    /* See AP_HAL::I2CDevice::set_address() */
+    void set_address(uint8_t address) override { _address = address; }
+
+    /* See AP_HAL::I2CDevice::set_retries() */
+    void set_retries(uint8_t retries) override { _retries = retries; }
+
+    /* AP_HAL::Device implementation */
+
+    /* See AP_HAL::Device::set_speed(): Empty implementation, not supported. */
+    bool set_speed(enum Device::Speed speed) override { return true; }
+
+    /* See AP_HAL::Device::transfer() */
+    bool transfer(const uint8_t *send, uint32_t send_len,
+                  uint8_t *recv, uint32_t recv_len) override;
+
+    bool read_registers_multiple(uint8_t first_reg, uint8_t *recv,
+                                 uint32_t recv_len, uint8_t times) override;
+
+    /* See AP_HAL::Device::get_semaphore() */
+    AP_HAL::Semaphore *get_semaphore() override;
+
+    /* See AP_HAL::Device::register_periodic_callback() */
+    AP_HAL::Device::PeriodicHandle register_periodic_callback(
+        uint32_t period_usec, AP_HAL::Device::PeriodicCb) override;
+
+    /* See AP_HAL::Device::adjust_periodic_callback() */
+    bool adjust_periodic_callback(
+        AP_HAL::Device::PeriodicHandle h, uint32_t period_usec) override;
+
+    /* set split transfers flag */
+    void set_split_transfers(bool set) override {
+        _split_transfers = set;
+    }
+
+    static void sitl_update();
+
+  // the following must be identical to the structure in SITL/SIM_I2C.h!
+#define I2C_M_RD 1
+#define I2C_RDWR 0
+    struct i2c_msg {
+        uint8_t addr;
+        uint8_t flags;
+        uint8_t *buf;
+        uint16_t len; // FIXME: what type should this be?
+    };
+    struct i2c_rdwr_ioctl_data {
+        i2c_msg *msgs;
+        uint8_t nmsgs;
+    };
+    // end "the following"
+
+protected:
+    I2CBus &_bus;
+    uint8_t _address;
+    uint8_t _retries;
+    bool _split_transfers = false;
+
+    bool _transfer(const uint8_t *send, uint32_t send_len,
+                   uint8_t *recv, uint32_t recv_len);
+};
+
+class HALSITL::I2CDeviceManager : public AP_HAL::I2CDeviceManager {
+public:
+    friend class I2CDevice;
+
+    static I2CDeviceManager *from(AP_HAL::I2CDeviceManager *i2c_mgr)
+    {
+        return static_cast<I2CDeviceManager*>(i2c_mgr);
+    }
+
+    I2CDeviceManager();
+    ~I2CDeviceManager() {};
+
+    void _timer_tick(); // in lieu of a thread-per-bus
+
+    /* AP_HAL::I2CDeviceManager implementation */
+    AP_HAL::OwnPtr<AP_HAL::I2CDevice> get_device(uint8_t bus, uint8_t address,
+                                                 uint32_t bus_clock=400000,
+                                                 bool use_smbus = false,
+                                                 uint32_t timeout_ms=4) override;
+
+protected:
+
+    #define NUM_SITL_I2C_BUSES 4
+    static I2CBus buses[];
+};

libraries/AP_HAL_SITL/SITL_State.cpp

@@ -95,6 +95,7 @@ void SITL_State::_sitl_setup(const char *home_str)
         sitl_model->set_gripper_epm(&_sitl->gripper_epm_sim);
         sitl_model->set_parachute(&_sitl->parachute_sim);
         sitl_model->set_precland(&_sitl->precland_sim);
+        sitl_model->set_i2c(&_sitl->i2c_sim);
 
         if (_use_fg_view) {
             fg_socket.connect(_fg_address, _fg_view_port);

libraries/AP_HAL_SITL/Scheduler.cpp

@@ -1,6 +1,7 @@
 #include <AP_HAL/AP_HAL.h>
 
 #include "AP_HAL_SITL.h"
+#include <AP_HAL_SITL/I2CDevice.h>
 #include "Scheduler.h"
 #include "UARTDriver.h"
 #include <sys/time.h>
@@ -240,6 +241,9 @@ void Scheduler::_run_io_procs()
     hal.uartH->_timer_tick();
     hal.storage->_timer_tick();
 
+    // in lieu of a thread-per-bus:
+    ((HALSITL::I2CDeviceManager*)(hal.i2c_mgr))->_timer_tick();
+
 #if SITL_STACK_CHECKING_ENABLED
     check_thread_stacks();
 #endif