src/devices/bus/drivers/platform/test/test/gpio.cc

// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <fuchsia/hardware/gpioimpl/cpp/banjo.h>
#include <fuchsia/hardware/platform/bus/c/banjo.h>
#include <fuchsia/hardware/platform/device/c/banjo.h>
#include <lib/ddk/debug.h>
#include <lib/ddk/driver.h>

#include <memory>

#include <ddktl/device.h>

#include "src/devices/bus/drivers/platform/test/test-gpio-bind.h"

#define DRIVER_NAME "test-gpio"

namespace gpio {

class TestGpioDevice;
using DeviceType = ddk::Device<TestGpioDevice>;

class TestGpioDevice : public DeviceType,
                       public ddk::GpioImplProtocol<TestGpioDevice, ddk::base_protocol> {
 public:
  static zx_status_t Create(zx_device_t* parent);

  explicit TestGpioDevice(zx_device_t* parent) : DeviceType(parent) {}

  zx_status_t Create(std::unique_ptr<TestGpioDevice>* out);
  zx_status_t Init();

  // Methods required by the ddk mixins
  void DdkRelease();

  zx_status_t GpioImplConfigIn(uint32_t pin, uint32_t flags);
  zx_status_t GpioImplConfigOut(uint32_t pin, uint8_t initial_value);
  zx_status_t GpioImplSetAltFunction(uint32_t pin, uint64_t function);
  zx_status_t GpioImplRead(uint32_t pin, uint8_t* out_value);
  zx_status_t GpioImplWrite(uint32_t pin, uint8_t value);
  zx_status_t GpioImplGetInterrupt(uint32_t pin, uint32_t flags, zx::interrupt* out_irq);
  zx_status_t GpioImplReleaseInterrupt(uint32_t pin);
  zx_status_t GpioImplSetPolarity(uint32_t pin, uint32_t polarity);
  zx_status_t GpioImplSetDriveStrength(uint32_t pin, uint64_t ua, uint64_t* out_actual_ua);

 private:
  static constexpr uint32_t PIN_COUNT = 10;

  // values for our pins
  bool pins_[PIN_COUNT] = {};
};

zx_status_t TestGpioDevice::Init() {
  pbus_protocol_t pbus;
  auto status = device_get_protocol(parent(), ZX_PROTOCOL_PBUS, &pbus);
  if (status != ZX_OK) {
    zxlogf(ERROR, "%s: ZX_PROTOCOL_PBUS not available %d", __func__, status);
    return status;
  }
  gpio_impl_protocol_t gpio_proto = {
      .ops = &gpio_impl_protocol_ops_,
      .ctx = this,
  };
  status = pbus_register_protocol(&pbus, ZX_PROTOCOL_GPIO_IMPL,
                                  reinterpret_cast<uint8_t*>(&gpio_proto), sizeof(gpio_proto));
  if (status != ZX_OK) {
    zxlogf(ERROR, "%s pbus_register_protocol failed %d", __func__, status);
    return status;
  }
  return ZX_OK;
}

zx_status_t TestGpioDevice::Create(zx_device_t* parent) {
  auto dev = std::make_unique<TestGpioDevice>(parent);
  pdev_protocol_t pdev;
  zx_status_t status;

  zxlogf(INFO, "TestGpioDevice::Create: %s ", DRIVER_NAME);

  status = device_get_protocol(parent, ZX_PROTOCOL_PDEV, &pdev);
  if (status != ZX_OK) {
    zxlogf(ERROR, "%s: could not get ZX_PROTOCOL_PDEV", __func__);
    return status;
  }

  status = dev->DdkAdd("test-gpio");
  if (status != ZX_OK) {
    zxlogf(ERROR, "%s: DdkAdd failed: %d", __func__, status);
    return status;
  }
  // devmgr is now in charge of dev.
  auto ptr = dev.release();

  return ptr->Init();
}

void TestGpioDevice::DdkRelease() { delete this; }

zx_status_t TestGpioDevice::GpioImplConfigIn(uint32_t pin, uint32_t flags) {
  if (pin >= PIN_COUNT) {
    return ZX_ERR_INVALID_ARGS;
  }
  return ZX_OK;
}

zx_status_t TestGpioDevice::GpioImplConfigOut(uint32_t pin, uint8_t initial_value) {
  if (pin >= PIN_COUNT) {
    return ZX_ERR_INVALID_ARGS;
  }
  return ZX_OK;
}

zx_status_t TestGpioDevice::GpioImplSetAltFunction(uint32_t pin, uint64_t function) {
  if (pin >= PIN_COUNT) {
    return ZX_ERR_INVALID_ARGS;
  }
  return ZX_OK;
}

zx_status_t TestGpioDevice::GpioImplRead(uint32_t pin, uint8_t* out_value) {
  if (pin >= PIN_COUNT) {
    return ZX_ERR_INVALID_ARGS;
  }
  *out_value = pins_[pin];
  return ZX_OK;
}

zx_status_t TestGpioDevice::GpioImplWrite(uint32_t pin, uint8_t value) {
  if (pin >= PIN_COUNT) {
    return ZX_ERR_INVALID_ARGS;
  }
  pins_[pin] = value;
  return ZX_OK;
}

zx_status_t TestGpioDevice::GpioImplGetInterrupt(uint32_t pin, uint32_t flags,
                                                 zx::interrupt* out_irq) {
  if (pin >= PIN_COUNT) {
    return ZX_ERR_INVALID_ARGS;
  }
  return ZX_OK;
}

zx_status_t TestGpioDevice::GpioImplReleaseInterrupt(uint32_t pin) {
  if (pin >= PIN_COUNT) {
    return ZX_ERR_INVALID_ARGS;
  }
  return ZX_OK;
}

zx_status_t TestGpioDevice::GpioImplSetPolarity(uint32_t pin, uint32_t polarity) {
  if (pin >= PIN_COUNT) {
    return ZX_ERR_INVALID_ARGS;
  }
  return ZX_OK;
}

zx_status_t TestGpioDevice::GpioImplSetDriveStrength(uint32_t pin, uint64_t ua,
                                                     uint64_t* out_actual_ua) {
  if (pin >= PIN_COUNT) {
    return ZX_ERR_INVALID_ARGS;
  }
  if (out_actual_ua) {
    *out_actual_ua = 0;
  }
  return ZX_OK;
}

zx_status_t test_gpio_bind(void* ctx, zx_device_t* parent) {
  return TestGpioDevice::Create(parent);
}

constexpr zx_driver_ops_t driver_ops = []() {
  zx_driver_ops_t driver_ops = {};
  driver_ops.version = DRIVER_OPS_VERSION;
  driver_ops.bind = test_gpio_bind;
  return driver_ops;
}();

}  // namespace gpio

ZIRCON_DRIVER(test_gpio, gpio::driver_ops, "zircon", "0.1");