system/dev/input/focaltech/ft_device.cpp

// 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 <ddk/debug.h>
#include <ddk/metadata.h>
#include <ddk/protocol/platform/device.h>
#include <ddk/protocol/i2c-lib.h>
#include <fbl/algorithm.h>
#include <fbl/auto_call.h>
#include <fbl/auto_lock.h>
#include <fbl/ref_counted.h>
#include <fbl/ref_ptr.h>
#include <hw/arch_ops.h>
#include <hw/reg.h>
#include <lib/focaltech/focaltech.h>
#include <zircon/compiler.h>

#include <stdio.h>
#include <string.h>

#include "ft_device.h"

namespace ft {

FtDevice::FtDevice(zx_device_t* device)
    : ddk::Device<FtDevice, ddk::Unbindable>(device) {
}

void FtDevice::ParseReport(ft3x27_finger_t* rpt, uint8_t* buf) {
    rpt->x = static_cast<uint16_t>(((buf[0] & 0x0f) << 8) + buf[1]);
    rpt->y = static_cast<uint16_t>(((buf[2] & 0x0f) << 8) + buf[3]);
    rpt->finger_id = static_cast<uint8_t>(
        ((buf[2] >> 2) & FT3X27_FINGER_ID_CONTACT_MASK) |
        (((buf[0] & 0xC0) == 0x80) ? 1 : 0));
}

int FtDevice::Thread() {
    zx_status_t status;
    zxlogf(INFO, "focaltouch: entering irq thread\n");
    while (true) {
        status = irq_.wait(nullptr);
        if (!running_.load()) {
            return ZX_OK;
        }
        if (status != ZX_OK) {
            zxlogf(ERROR, "focaltouch: Interrupt error %d\n", status);
        }
        uint8_t i2c_buf[kMaxPoints * kFingerRptSize + 1];
        status = Read(FTS_REG_CURPOINT, i2c_buf, kMaxPoints * kFingerRptSize + 1);
        if (status == ZX_OK) {
            fbl::AutoLock lock(&client_lock_);
            ft_rpt_.rpt_id = FT3X27_RPT_ID_TOUCH;
            ft_rpt_.contact_count = i2c_buf[0];
            for (uint i = 0; i < kMaxPoints; i++) {
                ParseReport(&ft_rpt_.fingers[i], &i2c_buf[i * kFingerRptSize + 1]);
            }
            if (client_.is_valid()) {
                client_.IoQueue(reinterpret_cast<uint8_t*>(&ft_rpt_), sizeof(ft3x27_touch_t));
            }
        } else {
            zxlogf(ERROR, "focaltouch: i2c read error\n");
        }
    }
    zxlogf(INFO, "focaltouch: exiting\n");
}

zx_status_t FtDevice::InitPdev() {
    pdev_protocol_t pdev;

    zx_status_t status = device_get_protocol(parent_, ZX_PROTOCOL_PDEV, &pdev);
    if (status != ZX_OK) {
        zxlogf(ERROR, "focaltouch: failed to acquire pdev\n");
        return status;
    }

    status = device_get_protocol(parent_, ZX_PROTOCOL_I2C, &i2c_);
    if (status != ZX_OK) {
        zxlogf(ERROR, "focaltouch: failed to acquire i2c\n");
        return status;
    }

    for (uint32_t i = 0; i < FT_PIN_COUNT; i++) {
        size_t actual;
        status = pdev_get_protocol(&pdev, ZX_PROTOCOL_GPIO, i, &gpios_[i], sizeof(gpios_[i]),
                                   &actual);
        if (status != ZX_OK) {
            return status;
        }
    }

    gpio_config_in(&gpios_[FT_INT_PIN], GPIO_NO_PULL);

    status = gpio_get_interrupt(&gpios_[FT_INT_PIN],
                                ZX_INTERRUPT_MODE_EDGE_LOW,
                                irq_.reset_and_get_address());
    if (status != ZX_OK) {
        return status;
    }

    uint32_t device_id;
    size_t actual;
    status = device_get_metadata(parent_, DEVICE_METADATA_PRIVATE, &device_id, sizeof(device_id),
                                 &actual);
    if (status != ZX_OK || sizeof(device_id) != actual) {
        zxlogf(ERROR, "focaltouch: failed to read metadata\n");
        return status == ZX_OK ? ZX_ERR_INTERNAL : status;
    }

    if (device_id == FOCALTECH_DEVICE_FT3X27) {
        descriptor_len_ = get_ft3x27_report_desc(&descriptor_);
    } else if (device_id == FOCALTECH_DEVICE_FT6336) {
        descriptor_len_ = get_ft6336_report_desc(&descriptor_);
    } else {
        zxlogf(ERROR, "focaltouch: unknown device ID %u\n", device_id);
        return ZX_ERR_INTERNAL;
    }

    return ZX_OK;
}

zx_status_t FtDevice::Create(zx_device_t* device) {

    zxlogf(INFO, "focaltouch: driver started...\n");

    auto ft_dev = fbl::make_unique<FtDevice>(device);
    zx_status_t status = ft_dev->InitPdev();
    if (status != ZX_OK) {
        zxlogf(ERROR, "focaltouch: Driver bind failed %d\n", status);
        return status;
    }

    auto thunk = [](void* arg) -> int {
        return reinterpret_cast<FtDevice*>(arg)->Thread();
    };

    auto cleanup = fbl::MakeAutoCall([&]() { ft_dev->ShutDown(); });

    ft_dev->running_.store(true);
    int ret = thrd_create_with_name(&ft_dev->thread_, thunk,
                                    reinterpret_cast<void*>(ft_dev.get()),
                                    "focaltouch-thread");
    ZX_DEBUG_ASSERT(ret == thrd_success);

    status = ft_dev->DdkAdd("focaltouch HidDevice");
    if (status != ZX_OK) {
        zxlogf(ERROR, "focaltouch: Could not create hid device: %d\n", status);
        return status;
    } else {
        zxlogf(INFO, "focaltouch: Added hid device\n");
    }

    cleanup.cancel();

    // device intentionally leaked as it is now held by DevMgr
    __UNUSED auto ptr = ft_dev.release();

    return ZX_OK;
}

zx_status_t FtDevice::HidbusQuery(uint32_t options, hid_info_t* info) {
    if (!info) {
        return ZX_ERR_INVALID_ARGS;
    }
    info->dev_num = 0;
    info->device_class = HID_DEVICE_CLASS_OTHER;
    info->boot_device = false;

    return ZX_OK;
}

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

void FtDevice::DdkUnbind() {
    ShutDown();
    DdkRemove();
}

zx_status_t FtDevice::ShutDown() {
    running_.store(false);
    irq_.destroy();
    thrd_join(thread_, NULL);
    {
        fbl::AutoLock lock(&client_lock_);
        //client_.clear();
    }
    return ZX_OK;
}

zx_status_t FtDevice::HidbusGetDescriptor(uint8_t desc_type, void** data, size_t* len) {

    fbl::AllocChecker ac;
    uint8_t* buf = new (&ac) uint8_t[descriptor_len_];
    if (!ac.check()) {
        return ZX_ERR_NO_MEMORY;
    }
    memcpy(buf, descriptor_, descriptor_len_);
    *data = buf;
    *len = descriptor_len_;
    return ZX_OK;
}

zx_status_t FtDevice::HidbusGetReport(uint8_t rpt_type, uint8_t rpt_id, void* data,
                                          size_t len, size_t* out_len) {
    return ZX_ERR_NOT_SUPPORTED;
}

zx_status_t FtDevice::HidbusSetReport(uint8_t rpt_type, uint8_t rpt_id, const void* data,
                                          size_t len) {
    return ZX_ERR_NOT_SUPPORTED;
}

zx_status_t FtDevice::HidbusGetIdle(uint8_t rpt_id, uint8_t* duration) {
    return ZX_ERR_NOT_SUPPORTED;
}

zx_status_t FtDevice::HidbusSetIdle(uint8_t rpt_id, uint8_t duration) {
    return ZX_ERR_NOT_SUPPORTED;
}

zx_status_t FtDevice::HidbusGetProtocol(uint8_t* protocol) {
    return ZX_ERR_NOT_SUPPORTED;
}

zx_status_t FtDevice::HidbusSetProtocol(uint8_t protocol) {
    return ZX_OK;
}

void FtDevice::HidbusStop() {
    fbl::AutoLock lock(&client_lock_);
    client_.clear();
}

zx_status_t FtDevice::HidbusStart(const hidbus_ifc_t* ifc) {
    fbl::AutoLock lock(&client_lock_);
    if (client_.is_valid()) {
        zxlogf(ERROR, "focaltouch: Already bound!\n");
        return ZX_ERR_ALREADY_BOUND;
    } else {
        client_ = ddk::HidbusIfcClient(ifc);
        zxlogf(INFO, "focaltouch: started\n");
    }
    return ZX_OK;
}

// simple i2c read for reading one register location
//  intended mostly for debug purposes
uint8_t FtDevice::Read(uint8_t addr) {
    uint8_t rbuf;
    i2c_write_read_sync(&i2c_, &addr, 1, &rbuf, 1);
    return rbuf;
}

zx_status_t FtDevice::Read(uint8_t addr, uint8_t* buf, size_t len) {
    // TODO(bradenkell): Remove this workaround when transfers of more than 8 bytes are supported on
    // the MT8167.
    while (len > 0) {
        size_t readlen = fbl::min(len, kMaxI2cTransferLength);

        zx_status_t status = i2c_write_read_sync(&i2c_, &addr, 1, buf, readlen);
        if (status != ZX_OK) {
            zxlogf(ERROR, "Failed to read i2c - %d\n", status);
            return status;
        }

        addr = static_cast<uint8_t>(addr + readlen);
        buf += readlen;
        len -= readlen;
    }

    return ZX_OK;
}
} //namespace ft

extern "C" zx_status_t ft_device_bind(void* ctx, zx_device_t* device, void** cookie) {
    return ft::FtDevice::Create(device);
}