// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2005-2006 Micronas USA Inc.
 */

#include <linux/module.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/unistd.h>
#include <linux/time.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <linux/device.h>
#include <linux/i2c.h>
#include <linux/firmware.h>
#include <linux/mutex.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <linux/videodev2.h>
#include <media/tuner.h>
#include <media/v4l2-common.h>
#include <media/v4l2-event.h>

#include "go7007-priv.h"

/*
 * Wait for an interrupt to be delivered from the GO7007SB and return
 * the associated value and data.
 *
 * Must be called with the hw_lock held.
 */
int go7007_read_interrupt(struct go7007 *go, u16 *value, u16 *data)
{
        go->interrupt_available = 0;
        go->hpi_ops->read_interrupt(go);
        if (wait_event_timeout(go->interrupt_waitq,
                                go->interrupt_available, 5*HZ) < 0) {
                v4l2_err(&go->v4l2_dev, "timeout waiting for read interrupt\n");
                return -1;
        }
        if (!go->interrupt_available)
                return -1;
        go->interrupt_available = 0;
        *value = go->interrupt_value & 0xfffe;
        *data = go->interrupt_data;
        return 0;
}
EXPORT_SYMBOL(go7007_read_interrupt);

/*
 * Read a register/address on the GO7007SB.
 *
 * Must be called with the hw_lock held.
 */
int go7007_read_addr(struct go7007 *go, u16 addr, u16 *data)
{
        int count = 100;
        u16 value;

        if (go7007_write_interrupt(go, 0x0010, addr) < 0)
                return -EIO;
        while (count-- > 0) {
                if (go7007_read_interrupt(go, &value, data) == 0 &&
                                value == 0xa000)
                        return 0;
        }
        return -EIO;
}
EXPORT_SYMBOL(go7007_read_addr);

/*
 * Send the boot firmware to the encoder, which just wakes it up and lets
 * us talk to the GPIO pins and on-board I2C adapter.
 *
 * Must be called with the hw_lock held.
 */
static int go7007_load_encoder(struct go7007 *go)
{
        const struct firmware *fw_entry;
        char fw_name[] = "go7007/go7007fw.bin";
        void *bounce;
        int fw_len;
        u16 intr_val, intr_data;

        if (go->boot_fw == NULL) {
                if (request_firmware(&fw_entry, fw_name, go->dev)) {
                        v4l2_err(go, "unable to load firmware from file \"%s\"\n", fw_name);
                        return -1;
                }
                if (fw_entry->size < 16 || memcmp(fw_entry->data, "WISGO7007FW", 11)) {
                        v4l2_err(go, "file \"%s\" does not appear to be go7007 firmware\n", fw_name);
                        release_firmware(fw_entry);
                        return -1;
                }
                fw_len = fw_entry->size - 16;
                bounce = kmemdup(fw_entry->data + 16, fw_len, GFP_KERNEL);
                if (bounce == NULL) {
                        v4l2_err(go, "unable to allocate %d bytes for firmware transfer\n", fw_len);
                        release_firmware(fw_entry);
                        return -1;
                }
                release_firmware(fw_entry);
                go->boot_fw_len = fw_len;
                go->boot_fw = bounce;
        }
        if (go7007_interface_reset(go) < 0 ||
            go7007_send_firmware(go, go->boot_fw, go->boot_fw_len) < 0 ||
            go7007_read_interrupt(go, &intr_val, &intr_data) < 0 ||
                        (intr_val & ~0x1) != 0x5a5a) {
                v4l2_err(go, "error transferring firmware\n");
                kfree(go->boot_fw);
                go->boot_fw = NULL;
                return -1;
        }
        return 0;
}

MODULE_FIRMWARE("go7007/go7007fw.bin");

/*
 * Boot the encoder and register the I2C adapter if requested.  Do the
 * minimum initialization necessary, since the board-specific code may
 * still need to probe the board ID.
 *
 * Must NOT be called with the hw_lock held.
 */
int go7007_boot_encoder(struct go7007 *go, int init_i2c)
{
        int ret;

        mutex_lock(&go->hw_lock);
        ret = go7007_load_encoder(go);
        mutex_unlock(&go->hw_lock);
        if (ret < 0)
                return -1;
        if (!init_i2c)
                return 0;
        if (go7007_i2c_init(go) < 0)
                return -1;
        go->i2c_adapter_online = 1;
        return 0;
}
EXPORT_SYMBOL(go7007_boot_encoder);

/*
 * Configure any hardware-related registers in the GO7007, such as GPIO
 * pins and bus parameters, which are board-specific.  This assumes
 * the boot firmware has already been downloaded.
 *
 * Must be called with the hw_lock held.
 */
static int go7007_init_encoder(struct go7007 *go)
{
        if (go->board_info->audio_flags & GO7007_AUDIO_I2S_MASTER) {
                go7007_write_addr(go, 0x1000, 0x0811);
                go7007_write_addr(go, 0x1000, 0x0c11);
        }
        switch (go->board_id) {
        case GO7007_BOARDID_MATRIX_REV:
                /* Set GPIO pin 0 to be an output (audio clock control) */
                go7007_write_addr(go, 0x3c82, 0x0001);
                go7007_write_addr(go, 0x3c80, 0x00fe);
                break;
        case GO7007_BOARDID_ADLINK_MPG24:
                /* set GPIO5 to be an output, currently low */
                go7007_write_addr(go, 0x3c82, 0x0000);
                go7007_write_addr(go, 0x3c80, 0x00df);
                break;
        case GO7007_BOARDID_ADS_USBAV_709:
                /* GPIO pin 0: audio clock control */
                /*      pin 2: TW9906 reset */
                /*      pin 3: capture LED */
                go7007_write_addr(go, 0x3c82, 0x000d);
                go7007_write_addr(go, 0x3c80, 0x00f2);
                break;
        }
        return 0;
}

/*
 * Send the boot firmware to the GO7007 and configure the registers.  This
 * is the only way to stop the encoder once it has started streaming video.
 *
 * Must be called with the hw_lock held.
 */
int go7007_reset_encoder(struct go7007 *go)
{
        if (go7007_load_encoder(go) < 0)
                return -1;
        return go7007_init_encoder(go);
}

/*
 * Attempt to instantiate an I2C client by ID, probably loading a module.
 */
static int init_i2c_module(struct i2c_adapter *adapter, const struct go_i2c *const i2c)
{
        struct go7007 *go = i2c_get_adapdata(adapter);
        struct v4l2_device *v4l2_dev = &go->v4l2_dev;
        struct v4l2_subdev *sd;
        struct i2c_board_info info;

        memset(&info, 0, sizeof(info));
        strscpy(info.type, i2c->type, sizeof(info.type));
        info.addr = i2c->addr;
        info.flags = i2c->flags;

        sd = v4l2_i2c_new_subdev_board(v4l2_dev, adapter, &info, NULL);
        if (sd) {
                if (i2c->is_video)
                        go->sd_video = sd;
                if (i2c->is_audio)
                        go->sd_audio = sd;
                return 0;
        }

        pr_info("go7007: probing for module i2c:%s failed\n", i2c->type);
        return -EINVAL;
}

/*
 * Detach and unregister the encoder.  The go7007 struct won't be freed
 * until v4l2 finishes releasing its resources and all associated fds are
 * closed by applications.
 */
static void go7007_remove(struct v4l2_device *v4l2_dev)
{
        struct go7007 *go = container_of(v4l2_dev, struct go7007, v4l2_dev);

        v4l2_device_unregister(v4l2_dev);
        if (go->hpi_ops->release)
                go->hpi_ops->release(go);
        if (go->i2c_adapter_online) {
                i2c_del_adapter(&go->i2c_adapter);
                go->i2c_adapter_online = 0;
        }

        kfree(go->boot_fw);
        go7007_v4l2_remove(go);
        kfree(go);
}

/*
 * Finalize the GO7007 hardware setup, register the on-board I2C adapter
 * (if used on this board), load the I2C client driver for the sensor
 * (SAA7115 or whatever) and other devices, and register the ALSA and V4L2
 * interfaces.
 *
 * Must NOT be called with the hw_lock held.
 */
int go7007_register_encoder(struct go7007 *go, unsigned num_i2c_devs)
{
        int i, ret;

        dev_info(go->dev, "go7007: registering new %s\n", go->name);

        go->v4l2_dev.release = go7007_remove;
        ret = v4l2_device_register(go->dev, &go->v4l2_dev);
        if (ret < 0)
                return ret;

        mutex_lock(&go->hw_lock);
        ret = go7007_init_encoder(go);
        mutex_unlock(&go->hw_lock);
        if (ret < 0)
                return ret;

        ret = go7007_v4l2_ctrl_init(go);
        if (ret < 0)
                return ret;

        if (!go->i2c_adapter_online &&
                        go->board_info->flags & GO7007_BOARD_USE_ONBOARD_I2C) {
                ret = go7007_i2c_init(go);
                if (ret < 0)
                        return ret;
                go->i2c_adapter_online = 1;
        }
        if (go->i2c_adapter_online) {
                if (go->board_id == GO7007_BOARDID_ADS_USBAV_709) {
                        /* Reset the TW9906 */
                        go7007_write_addr(go, 0x3c82, 0x0009);
                        msleep(50);
                        go7007_write_addr(go, 0x3c82, 0x000d);
                }
                for (i = 0; i < num_i2c_devs; ++i)
                        init_i2c_module(&go->i2c_adapter, &go->board_info->i2c_devs[i]);

                if (go->tuner_type >= 0) {
                        struct tuner_setup setup = {
                                .addr = ADDR_UNSET,
                                .type = go->tuner_type,
                                .mode_mask = T_ANALOG_TV,
                        };

                        v4l2_device_call_all(&go->v4l2_dev, 0, tuner,
                                s_type_addr, &setup);
                }
                if (go->board_id == GO7007_BOARDID_ADLINK_MPG24)
                        v4l2_subdev_call(go->sd_video, video, s_routing,
                                        0, 0, go->channel_number + 1);
        }

        ret = go7007_v4l2_init(go);
        if (ret < 0)
                return ret;

        if (go->board_info->flags & GO7007_BOARD_HAS_AUDIO) {
                go->audio_enabled = 1;
                go7007_snd_init(go);
        }
        return 0;
}
EXPORT_SYMBOL(go7007_register_encoder);

/*
 * Send the encode firmware to the encoder, which will cause it
 * to immediately start delivering the video and audio streams.
 *
 * Must be called with the hw_lock held.
 */
int go7007_start_encoder(struct go7007 *go)
{
        u8 *fw;
        int fw_len, rv = 0, i, x, y;
        u16 intr_val, intr_data;

        go->modet_enable = 0;
        for (i = 0; i < 4; i++)
                go->modet[i].enable = 0;

        switch (v4l2_ctrl_g_ctrl(go->modet_mode)) {
        case V4L2_DETECT_MD_MODE_GLOBAL:
                memset(go->modet_map, 0, sizeof(go->modet_map));
                go->modet[0].enable = 1;
                go->modet_enable = 1;
                break;
        case V4L2_DETECT_MD_MODE_REGION_GRID:
                for (y = 0; y < go->height / 16; y++) {
                        for (x = 0; x < go->width / 16; x++) {
                                int idx = y * go->width / 16 + x;

                                go->modet[go->modet_map[idx]].enable = 1;
                        }
                }
                go->modet_enable = 1;
                break;
        }

        if (go->dvd_mode)
                go->modet_enable = 0;

        if (go7007_construct_fw_image(go, &fw, &fw_len) < 0)
                return -1;

        if (go7007_send_firmware(go, fw, fw_len) < 0 ||
                        go7007_read_interrupt(go, &intr_val, &intr_data) < 0) {
                v4l2_err(&go->v4l2_dev, "error transferring firmware\n");
                rv = -1;
                goto start_error;
        }

        go->state = STATE_DATA;
        go->parse_length = 0;
        go->seen_frame = 0;
        if (go7007_stream_start(go) < 0) {
                v4l2_err(&go->v4l2_dev, "error starting stream transfer\n");
                rv = -1;
                goto start_error;
        }

start_error:
        kfree(fw);
        return rv;
}

/*
 * Store a byte in the current video buffer, if there is one.
 */
static inline void store_byte(struct go7007_buffer *vb, u8 byte)
{
        if (vb && vb->vb.vb2_buf.planes[0].bytesused < GO7007_BUF_SIZE) {
                u8 *ptr = vb2_plane_vaddr(&vb->vb.vb2_buf, 0);

                ptr[vb->vb.vb2_buf.planes[0].bytesused++] = byte;
        }
}

static void go7007_set_motion_regions(struct go7007 *go, struct go7007_buffer *vb,
                u32 motion_regions)
{
        if (motion_regions != go->modet_event_status) {
                struct v4l2_event ev = {
                        .type = V4L2_EVENT_MOTION_DET,
                        .u.motion_det = {
                                .flags = V4L2_EVENT_MD_FL_HAVE_FRAME_SEQ,
                                .frame_sequence = vb->vb.sequence,
                                .region_mask = motion_regions,
                        },
                };

                v4l2_event_queue(&go->vdev, &ev);
                go->modet_event_status = motion_regions;
        }
}

/*
 * Determine regions with motion and send a motion detection event
 * in case of changes.
 */
static void go7007_motion_regions(struct go7007 *go, struct go7007_buffer *vb)
{
        u32 *bytesused = &vb->vb.vb2_buf.planes[0].bytesused;
        unsigned motion[4] = { 0, 0, 0, 0 };
        u32 motion_regions = 0;
        unsigned stride = (go->width + 7) >> 3;
        unsigned x, y;
        int i;

        for (i = 0; i < 216; ++i)
                store_byte(vb, go->active_map[i]);
        for (y = 0; y < go->height / 16; y++) {
                for (x = 0; x < go->width / 16; x++) {
                        if (!(go->active_map[y * stride + (x >> 3)] & (1 << (x & 7))))
                                continue;
                        motion[go->modet_map[y * (go->width / 16) + x]]++;
                }
        }
        motion_regions = ((motion[0] > 0) << 0) |
                         ((motion[1] > 0) << 1) |
                         ((motion[2] > 0) << 2) |
                         ((motion[3] > 0) << 3);
        *bytesused -= 216;
        go7007_set_motion_regions(go, vb, motion_regions);
}

/*
 * Deliver the last video buffer and get a new one to start writing to.
 */
static struct go7007_buffer *frame_boundary(struct go7007 *go, struct go7007_buffer *vb)
{
        u32 *bytesused;
        struct go7007_buffer *vb_tmp = NULL;
        unsigned long flags;

        if (vb == NULL) {
                spin_lock_irqsave(&go->spinlock, flags);
                if (!list_empty(&go->vidq_active))
                        vb = go->active_buf =
                                list_first_entry(&go->vidq_active, struct go7007_buffer, list);
                spin_unlock_irqrestore(&go->spinlock, flags);
                go->next_seq++;
                return vb;
        }
        bytesused = &vb->vb.vb2_buf.planes[0].bytesused;

        vb->vb.sequence = go->next_seq++;
        if (vb->modet_active && *bytesused + 216 < GO7007_BUF_SIZE)
                go7007_motion_regions(go, vb);
        else
                go7007_set_motion_regions(go, vb, 0);

        vb->vb.vb2_buf.timestamp = ktime_get_ns();
        vb_tmp = vb;
        spin_lock_irqsave(&go->spinlock, flags);
        list_del(&vb->list);
        if (list_empty(&go->vidq_active))
                vb = NULL;
        else
                vb = list_first_entry(&go->vidq_active,
                                struct go7007_buffer, list);
        go->active_buf = vb;
        spin_unlock_irqrestore(&go->spinlock, flags);
        vb2_buffer_done(&vb_tmp->vb.vb2_buf, VB2_BUF_STATE_DONE);
        return vb;
}

static void write_bitmap_word(struct go7007 *go)
{
        int x, y, i, stride = ((go->width >> 4) + 7) >> 3;

        for (i = 0; i < 16; ++i) {
                y = (((go->parse_length - 1) << 3) + i) / (go->width >> 4);
                x = (((go->parse_length - 1) << 3) + i) % (go->width >> 4);
                if (stride * y + (x >> 3) < sizeof(go->active_map))
                        go->active_map[stride * y + (x >> 3)] |=
                                        (go->modet_word & 1) << (x & 0x7);
                go->modet_word >>= 1;
        }
}

/*
 * Parse a chunk of the video stream into frames.  The frames are not
 * delimited by the hardware, so we have to parse the frame boundaries
 * based on the type of video stream we're receiving.
 */
void go7007_parse_video_stream(struct go7007 *go, u8 *buf, int length)
{
        struct go7007_buffer *vb = go->active_buf;
        int i, seq_start_code = -1, gop_start_code = -1, frame_start_code = -1;

        switch (go->format) {
        case V4L2_PIX_FMT_MPEG4:
                seq_start_code = 0xB0;
                gop_start_code = 0xB3;
                frame_start_code = 0xB6;
                break;
        case V4L2_PIX_FMT_MPEG1:
        case V4L2_PIX_FMT_MPEG2:
                seq_start_code = 0xB3;
                gop_start_code = 0xB8;
                frame_start_code = 0x00;
                break;
        }

        for (i = 0; i < length; ++i) {
                if (vb && vb->vb.vb2_buf.planes[0].bytesused >=
                                GO7007_BUF_SIZE - 3) {
                        v4l2_info(&go->v4l2_dev, "dropping oversized frame\n");
                        vb2_set_plane_payload(&vb->vb.vb2_buf, 0, 0);
                        vb->frame_offset = 0;
                        vb->modet_active = 0;
                        vb = go->active_buf = NULL;
                }

                switch (go->state) {
                case STATE_DATA:
                        switch (buf[i]) {
                        case 0x00:
                                go->state = STATE_00;
                                break;
                        case 0xFF:
                                go->state = STATE_FF;
                                break;
                        default:
                                store_byte(vb, buf[i]);
                                break;
                        }
                        break;
                case STATE_00:
                        switch (buf[i]) {
                        case 0x00:
                                go->state = STATE_00_00;
                                break;
                        case 0xFF:
                                store_byte(vb, 0x00);
                                go->state = STATE_FF;
                                break;
                        default:
                                store_byte(vb, 0x00);
                                store_byte(vb, buf[i]);
                                go->state = STATE_DATA;
                                break;
                        }
                        break;
                case STATE_00_00:
                        switch (buf[i]) {
                        case 0x00:
                                store_byte(vb, 0x00);
                                /* go->state remains STATE_00_00 */
                                break;
                        case 0x01:
                                go->state = STATE_00_00_01;
                                break;
                        case 0xFF:
                                store_byte(vb, 0x00);
                                store_byte(vb, 0x00);
                                go->state = STATE_FF;
                                break;
                        default:
                                store_byte(vb, 0x00);
                                store_byte(vb, 0x00);
                                store_byte(vb, buf[i]);
                                go->state = STATE_DATA;
                                break;
                        }
                        break;
                case STATE_00_00_01:
                        if (buf[i] == 0xF8 && go->modet_enable == 0) {
                                /* MODET start code, but MODET not enabled */
                                store_byte(vb, 0x00);
                                store_byte(vb, 0x00);
                                store_byte(vb, 0x01);
                                store_byte(vb, 0xF8);
                                go->state = STATE_DATA;
                                break;
                        }
                        /* If this is the start of a new MPEG frame,
                         * get a new buffer */
                        if ((go->format == V4L2_PIX_FMT_MPEG1 ||
                             go->format == V4L2_PIX_FMT_MPEG2 ||
                             go->format == V4L2_PIX_FMT_MPEG4) &&
                            (buf[i] == seq_start_code ||
                             buf[i] == gop_start_code ||
                             buf[i] == frame_start_code)) {
                                if (vb == NULL || go->seen_frame)
                                        vb = frame_boundary(go, vb);
                                go->seen_frame = buf[i] == frame_start_code;
                                if (vb && go->seen_frame)
                                        vb->frame_offset =
                                        vb->vb.vb2_buf.planes[0].bytesused;
                        }
                        /* Handle any special chunk types, or just write the
                         * start code to the (potentially new) buffer */
                        switch (buf[i]) {
                        case 0xF5: /* timestamp */
                                go->parse_length = 12;
                                go->state = STATE_UNPARSED;
                                break;
                        case 0xF6: /* vbi */
                                go->state = STATE_VBI_LEN_A;
                                break;
                        case 0xF8: /* MD map */
                                go->parse_length = 0;
                                memset(go->active_map, 0,
                                                sizeof(go->active_map));
                                go->state = STATE_MODET_MAP;
                                break;
                        case 0xFF: /* Potential JPEG start code */
                                store_byte(vb, 0x00);
                                store_byte(vb, 0x00);
                                store_byte(vb, 0x01);
                                go->state = STATE_FF;
                                break;
                        default:
                                store_byte(vb, 0x00);
                                store_byte(vb, 0x00);
                                store_byte(vb, 0x01);
                                store_byte(vb, buf[i]);
                                go->state = STATE_DATA;
                                break;
                        }
                        break;
                case STATE_FF:
                        switch (buf[i]) {
                        case 0x00:
                                store_byte(vb, 0xFF);
                                go->state = STATE_00;
                                break;
                        case 0xFF:
                                store_byte(vb, 0xFF);
                                /* go->state remains STATE_FF */
                                break;
                        case 0xD8:
                                if (go->format == V4L2_PIX_FMT_MJPEG)
                                        vb = frame_boundary(go, vb);
                                fallthrough;
                        default:
                                store_byte(vb, 0xFF);
                                store_byte(vb, buf[i]);
                                go->state = STATE_DATA;
                                break;
                        }
                        break;
                case STATE_VBI_LEN_A:
                        go->parse_length = buf[i] << 8;
                        go->state = STATE_VBI_LEN_B;
                        break;
                case STATE_VBI_LEN_B:
                        go->parse_length |= buf[i];
                        if (go->parse_length > 0)
                                go->state = STATE_UNPARSED;
                        else
                                go->state = STATE_DATA;
                        break;
                case STATE_MODET_MAP:
                        if (go->parse_length < 204) {
                                if (go->parse_length & 1) {
                                        go->modet_word |= buf[i];
                                        write_bitmap_word(go);
                                } else
                                        go->modet_word = buf[i] << 8;
                        } else if (go->parse_length == 207 && vb) {
                                vb->modet_active = buf[i];
                        }
                        if (++go->parse_length == 208)
                                go->state = STATE_DATA;
                        break;
                case STATE_UNPARSED:
                        if (--go->parse_length == 0)
                                go->state = STATE_DATA;
                        break;
                }
        }
}
EXPORT_SYMBOL(go7007_parse_video_stream);

/*
 * Allocate a new go7007 struct.  Used by the hardware-specific probe.
 */
struct go7007 *go7007_alloc(const struct go7007_board_info *board,
                                                struct device *dev)
{
        struct go7007 *go;

        go = kzalloc_obj(struct go7007);
        if (go == NULL)
                return NULL;
        go->dev = dev;
        go->board_info = board;
        go->tuner_type = -1;
        mutex_init(&go->hw_lock);
        init_waitqueue_head(&go->frame_waitq);
        spin_lock_init(&go->spinlock);
        go->status = STATUS_INIT;
        init_waitqueue_head(&go->interrupt_waitq);
        go7007_update_board(go);
        go->format = V4L2_PIX_FMT_MJPEG;
        go->bitrate = 1500000;
        go->fps_scale = 1;
        go->aspect_ratio = GO7007_RATIO_1_1;

        return go;
}
EXPORT_SYMBOL(go7007_alloc);

void go7007_update_board(struct go7007 *go)
{
        const struct go7007_board_info *board = go->board_info;

        if (board->sensor_flags & GO7007_SENSOR_TV) {
                go->standard = GO7007_STD_NTSC;
                go->std = V4L2_STD_NTSC_M;
                go->width = 720;
                go->height = 480;
                go->sensor_framerate = 30000;
        } else {
                go->standard = GO7007_STD_OTHER;
                go->width = board->sensor_width;
                go->height = board->sensor_height;
                go->sensor_framerate = board->sensor_framerate;
        }
        go->encoder_v_offset = board->sensor_v_offset;
        go->encoder_h_offset = board->sensor_h_offset;
}
EXPORT_SYMBOL(go7007_update_board);

MODULE_DESCRIPTION("WIS GO7007 MPEG encoder support");
MODULE_LICENSE("GPL v2");