// SPDX-License-Identifier: GPL-2.0
/*
 * stf_capture.c
 *
 * StarFive Camera Subsystem - capture device
 *
 * Copyright (C) 2021-2023 StarFive Technology Co., Ltd.
 */

#include "stf-camss.h"

static const char * const stf_cap_names[] = {
	"capture_raw",
	"capture_yuv",
};

static const struct stfcamss_format_info stf_wr_fmts[] = {
	{
		.code = MEDIA_BUS_FMT_SRGGB10_1X10,
		.pixelformat = V4L2_PIX_FMT_SRGGB10,
		.planes = 1,
		.vsub = { 1 },
		.bpp = 10,
	},
	{
		.code = MEDIA_BUS_FMT_SGRBG10_1X10,
		.pixelformat = V4L2_PIX_FMT_SGRBG10,
		.planes = 1,
		.vsub = { 1 },
		.bpp = 10,
	},
	{
		.code = MEDIA_BUS_FMT_SGBRG10_1X10,
		.pixelformat = V4L2_PIX_FMT_SGBRG10,
		.planes = 1,
		.vsub = { 1 },
		.bpp = 10,
	},
	{
		.code = MEDIA_BUS_FMT_SBGGR10_1X10,
		.pixelformat = V4L2_PIX_FMT_SBGGR10,
		.planes = 1,
		.vsub = { 1 },
		.bpp = 10,
	},
};

static const struct stfcamss_format_info stf_isp_fmts[] = {
	{
		.code = MEDIA_BUS_FMT_YUYV8_1_5X8,
		.pixelformat = V4L2_PIX_FMT_NV12,
		.planes = 2,
		.vsub = { 1, 2 },
		.bpp = 8,
	},
};

static inline struct stf_capture *to_stf_capture(struct stfcamss_video *video)
{
	return container_of(video, struct stf_capture, video);
}

static void stf_set_raw_addr(struct stfcamss *stfcamss, dma_addr_t addr)
{
	stf_syscon_reg_write(stfcamss, VIN_START_ADDR_O, (long)addr);
	stf_syscon_reg_write(stfcamss, VIN_START_ADDR_N, (long)addr);
}

static void stf_set_yuv_addr(struct stfcamss *stfcamss,
			     dma_addr_t y_addr, dma_addr_t uv_addr)
{
	stf_isp_reg_write(stfcamss, ISP_REG_Y_PLANE_START_ADDR, y_addr);
	stf_isp_reg_write(stfcamss, ISP_REG_UV_PLANE_START_ADDR, uv_addr);
}

static void stf_init_addrs(struct stfcamss_video *video)
{
	struct stf_capture *cap = to_stf_capture(video);
	struct stf_v_buf *output = &cap->buffers;
	dma_addr_t addr0, addr1;

	output->active_buf = 0;

	if (!output->buf[0])
		return;

	addr0 = output->buf[0]->addr[0];
	addr1 = output->buf[0]->addr[1];

	if (cap->type == STF_CAPTURE_RAW)
		stf_set_raw_addr(video->stfcamss, addr0);
	else if (cap->type == STF_CAPTURE_YUV)
		stf_set_yuv_addr(video->stfcamss, addr0, addr1);
}

static struct stfcamss_buffer *stf_buf_get_pending(struct stf_v_buf *output)
{
	struct stfcamss_buffer *buffer = NULL;

	if (!list_empty(&output->pending_bufs)) {
		buffer = list_first_entry(&output->pending_bufs,
					  struct stfcamss_buffer,
					  queue);
		list_del(&buffer->queue);
	}

	return buffer;
}

static void stf_cap_s_cfg(struct stfcamss_video *video)
{
	struct stf_capture *cap = to_stf_capture(video);
	struct stf_v_buf *output = &cap->buffers;
	unsigned long flags;

	spin_lock_irqsave(&output->lock, flags);

	output->state = STF_OUTPUT_IDLE;
	output->buf[0] = stf_buf_get_pending(output);

	if (!output->buf[0] && output->buf[1]) {
		output->buf[0] = output->buf[1];
		output->buf[1] = NULL;
	}

	if (output->buf[0])
		output->state = STF_OUTPUT_SINGLE;

	output->sequence = 0;
	stf_init_addrs(video);

	spin_unlock_irqrestore(&output->lock, flags);
}

static int stf_cap_s_cleanup(struct stfcamss_video *video)
{
	struct stf_capture *cap = to_stf_capture(video);
	struct stf_v_buf *output = &cap->buffers;
	unsigned long flags;

	spin_lock_irqsave(&output->lock, flags);

	output->state = STF_OUTPUT_OFF;

	spin_unlock_irqrestore(&output->lock, flags);

	return 0;
}

static void stf_wr_data_en(struct stfcamss_video *video)
{
	struct stf_capture *cap = to_stf_capture(video);
	struct stfcamss *stfcamss = cap->video.stfcamss;

	stf_syscon_reg_set_bit(stfcamss, VIN_CHANNEL_SEL_EN, U0_VIN_AXIWR0_EN);
}

static void stf_wr_irq_enable(struct stfcamss_video *video)
{
	struct stf_capture *cap = to_stf_capture(video);
	struct stfcamss *stfcamss = cap->video.stfcamss;

	stf_syscon_reg_clear_bit(stfcamss, VIN_INRT_PIX_CFG, U0_VIN_INTR_M);
}

static void stf_wr_irq_disable(struct stfcamss_video *video)
{
	struct stf_capture *cap = to_stf_capture(video);
	struct stfcamss *stfcamss = cap->video.stfcamss;

	stf_syscon_reg_set_bit(stfcamss, VIN_INRT_PIX_CFG, U0_VIN_INTR_CLEAN);
	stf_syscon_reg_clear_bit(stfcamss, VIN_INRT_PIX_CFG, U0_VIN_INTR_CLEAN);
	stf_syscon_reg_set_bit(stfcamss, VIN_INRT_PIX_CFG, U0_VIN_INTR_M);
}

static void stf_channel_set(struct stfcamss_video *video)
{
	struct stf_capture *cap = to_stf_capture(video);
	struct stfcamss *stfcamss = cap->video.stfcamss;
	u32 val;

	if (cap->type == STF_CAPTURE_RAW) {
		val = stf_syscon_reg_read(stfcamss, VIN_CHANNEL_SEL_EN);
		val &= ~U0_VIN_CHANNEL_SEL_MASK;
		val |= CHANNEL(0);
		stf_syscon_reg_write(stfcamss, VIN_CHANNEL_SEL_EN, val);

		val = stf_syscon_reg_read(stfcamss, VIN_INRT_PIX_CFG);
		val &= ~U0_VIN_PIX_CT_MASK;
		val |= PIX_CT(1);

		val &= ~U0_VIN_PIXEL_HEIGH_BIT_SEL_MAKS;
		val |= PIXEL_HEIGH_BIT_SEL(0);

		val &= ~U0_VIN_PIX_CNT_END_MASK;
		val |= PIX_CNT_END(IMAGE_MAX_WIDTH / 4 - 1);

		stf_syscon_reg_write(stfcamss, VIN_INRT_PIX_CFG, val);
	} else if (cap->type == STF_CAPTURE_YUV) {
		val = stf_syscon_reg_read(stfcamss, VIN_CFG_REG);
		val &= ~U0_VIN_MIPI_BYTE_EN_ISP0_MASK;
		val |= U0_VIN_MIPI_BYTE_EN_ISP0(0);

		val &= ~U0_VIN_MIPI_CHANNEL_SEL0_MASK;
		val |= U0_VIN_MIPI_CHANNEL_SEL0(0);

		val &= ~U0_VIN_PIX_NUM_MASK;
		val |= U0_VIN_PIX_NUM(0);

		val &= ~U0_VIN_P_I_MIPI_HAEDER_EN0_MASK;
		val |= U0_VIN_P_I_MIPI_HAEDER_EN0(1);

		stf_syscon_reg_write(stfcamss, VIN_CFG_REG, val);
	}
}

static void stf_capture_start(struct stfcamss_video *video)
{
	struct stf_capture *cap = to_stf_capture(video);

	stf_channel_set(video);
	if (cap->type == STF_CAPTURE_RAW) {
		stf_wr_irq_enable(video);
		stf_wr_data_en(video);
	}

	stf_cap_s_cfg(video);
}

static void stf_capture_stop(struct stfcamss_video *video)
{
	struct stf_capture *cap = to_stf_capture(video);

	if (cap->type == STF_CAPTURE_RAW)
		stf_wr_irq_disable(video);

	stf_cap_s_cleanup(video);
}

static void stf_capture_init(struct stfcamss *stfcamss, struct stf_capture *cap)
{
	cap->buffers.state = STF_OUTPUT_OFF;
	cap->buffers.buf[0] = NULL;
	cap->buffers.buf[1] = NULL;
	cap->buffers.active_buf = 0;
	atomic_set(&cap->buffers.frame_skip, 4);
	INIT_LIST_HEAD(&cap->buffers.pending_bufs);
	INIT_LIST_HEAD(&cap->buffers.ready_bufs);
	spin_lock_init(&cap->buffers.lock);

	cap->video.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
	cap->video.stfcamss = stfcamss;
	cap->video.bpl_alignment = 16 * 8;

	if (cap->type == STF_CAPTURE_RAW) {
		cap->video.formats = stf_wr_fmts;
		cap->video.nformats = ARRAY_SIZE(stf_wr_fmts);
		cap->video.bpl_alignment = 8;
	} else if (cap->type == STF_CAPTURE_YUV) {
		cap->video.formats = stf_isp_fmts;
		cap->video.nformats = ARRAY_SIZE(stf_isp_fmts);
		cap->video.bpl_alignment = 1;
	}
}

static void stf_buf_add_ready(struct stf_v_buf *output,
			      struct stfcamss_buffer *buffer)
{
	INIT_LIST_HEAD(&buffer->queue);
	list_add_tail(&buffer->queue, &output->ready_bufs);
}

static struct stfcamss_buffer *stf_buf_get_ready(struct stf_v_buf *output)
{
	struct stfcamss_buffer *buffer = NULL;

	if (!list_empty(&output->ready_bufs)) {
		buffer = list_first_entry(&output->ready_bufs,
					  struct stfcamss_buffer,
					  queue);
		list_del(&buffer->queue);
	}

	return buffer;
}

static void stf_buf_add_pending(struct stf_v_buf *output,
				struct stfcamss_buffer *buffer)
{
	INIT_LIST_HEAD(&buffer->queue);
	list_add_tail(&buffer->queue, &output->pending_bufs);
}

static void stf_buf_update_on_last(struct stf_v_buf *output)
{
	switch (output->state) {
	case STF_OUTPUT_CONTINUOUS:
		output->state = STF_OUTPUT_SINGLE;
		output->active_buf = !output->active_buf;
		break;
	case STF_OUTPUT_SINGLE:
		output->state = STF_OUTPUT_STOPPING;
		break;
	default:
		break;
	}
}

static void stf_buf_update_on_next(struct stf_v_buf *output)
{
	switch (output->state) {
	case STF_OUTPUT_CONTINUOUS:
		output->active_buf = !output->active_buf;
		break;
	case STF_OUTPUT_SINGLE:
	default:
		break;
	}
}

static void stf_buf_update_on_new(struct stfcamss_video *video,
				  struct stfcamss_buffer *new_buf)
{
	struct stf_capture *cap = to_stf_capture(video);
	struct stf_v_buf *output = &cap->buffers;

	switch (output->state) {
	case STF_OUTPUT_SINGLE:
		stf_buf_add_pending(output, new_buf);
		break;
	case STF_OUTPUT_IDLE:
		if (!output->buf[0]) {
			output->buf[0] = new_buf;
			stf_init_addrs(video);
			output->state = STF_OUTPUT_SINGLE;
		} else {
			stf_buf_add_pending(output, new_buf);
		}
		break;
	case STF_OUTPUT_STOPPING:
		if (output->last_buffer) {
			output->buf[output->active_buf] = output->last_buffer;
			output->last_buffer = NULL;
		}

		output->state = STF_OUTPUT_SINGLE;
		stf_buf_add_pending(output, new_buf);
		break;
	case STF_OUTPUT_CONTINUOUS:
	default:
		stf_buf_add_pending(output, new_buf);
		break;
	}
}

static void stf_buf_flush(struct stf_v_buf *output, enum vb2_buffer_state state)
{
	struct stfcamss_buffer *buf;
	struct stfcamss_buffer *t;

	list_for_each_entry_safe(buf, t, &output->pending_bufs, queue) {
		vb2_buffer_done(&buf->vb.vb2_buf, state);
		list_del(&buf->queue);
	}
	list_for_each_entry_safe(buf, t, &output->ready_bufs, queue) {
		vb2_buffer_done(&buf->vb.vb2_buf, state);
		list_del(&buf->queue);
	}
}

static void stf_buf_done(struct stf_v_buf *output)
{
	struct stfcamss_buffer *ready_buf;
	u64 ts = ktime_get_ns();
	unsigned long flags;

	if (output->state == STF_OUTPUT_OFF ||
	    output->state == STF_OUTPUT_RESERVED)
		return;

	spin_lock_irqsave(&output->lock, flags);

	while ((ready_buf = stf_buf_get_ready(output))) {
		ready_buf->vb.vb2_buf.timestamp = ts;
		ready_buf->vb.sequence = output->sequence++;

		vb2_buffer_done(&ready_buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
	}

	spin_unlock_irqrestore(&output->lock, flags);
}

static void stf_change_buffer(struct stf_v_buf *output)
{
	struct stf_capture *cap = container_of(output, struct stf_capture,
					       buffers);
	struct stfcamss *stfcamss = cap->video.stfcamss;
	struct stfcamss_buffer *ready_buf;
	dma_addr_t *new_addr;
	unsigned long flags;
	u32 active_index;

	if (output->state == STF_OUTPUT_OFF ||
	    output->state == STF_OUTPUT_STOPPING ||
	    output->state == STF_OUTPUT_RESERVED ||
	    output->state == STF_OUTPUT_IDLE)
		return;

	spin_lock_irqsave(&output->lock, flags);

	active_index = output->active_buf;

	ready_buf = output->buf[active_index];
	if (!ready_buf) {
		dev_dbg(stfcamss->dev, "missing ready buf %d %d.\n",
			active_index, output->state);
		active_index = !active_index;
		ready_buf = output->buf[active_index];
		if (!ready_buf) {
			dev_dbg(stfcamss->dev,
				"missing ready buf2 %d %d.\n",
				active_index, output->state);
			goto out_unlock;
		}
	}

	/* Get next buffer */
	output->buf[active_index] = stf_buf_get_pending(output);
	if (!output->buf[active_index]) {
		new_addr = ready_buf->addr;
		stf_buf_update_on_last(output);
	} else {
		new_addr = output->buf[active_index]->addr;
		stf_buf_update_on_next(output);
	}

	if (output->state == STF_OUTPUT_STOPPING) {
		output->last_buffer = ready_buf;
	} else {
		if (cap->type == STF_CAPTURE_RAW)
			stf_set_raw_addr(stfcamss, new_addr[0]);
		else if (cap->type == STF_CAPTURE_YUV)
			stf_set_yuv_addr(stfcamss, new_addr[0], new_addr[1]);

		stf_buf_add_ready(output, ready_buf);
	}

out_unlock:
	spin_unlock_irqrestore(&output->lock, flags);
}

irqreturn_t stf_wr_irq_handler(int irq, void *priv)
{
	struct stfcamss *stfcamss = priv;
	struct stf_capture *cap = &stfcamss->captures[STF_CAPTURE_RAW];

	if (atomic_dec_if_positive(&cap->buffers.frame_skip) < 0) {
		stf_change_buffer(&cap->buffers);
		stf_buf_done(&cap->buffers);
	}

	stf_syscon_reg_set_bit(stfcamss, VIN_INRT_PIX_CFG, U0_VIN_INTR_CLEAN);
	stf_syscon_reg_clear_bit(stfcamss, VIN_INRT_PIX_CFG, U0_VIN_INTR_CLEAN);

	return IRQ_HANDLED;
}

irqreturn_t stf_isp_irq_handler(int irq, void *priv)
{
	struct stfcamss *stfcamss = priv;
	struct stf_capture *cap = &stfcamss->captures[STF_CAPTURE_YUV];
	u32 status;

	status = stf_isp_reg_read(stfcamss, ISP_REG_ISP_CTRL_0);
	if (status & ISPC_ISP) {
		if (status & ISPC_ENUO)
			stf_buf_done(&cap->buffers);

		stf_isp_reg_write(stfcamss, ISP_REG_ISP_CTRL_0,
				  (status & ~ISPC_INT_ALL_MASK) |
				  ISPC_ISP | ISPC_CSI | ISPC_SC);
	}

	return IRQ_HANDLED;
}

irqreturn_t stf_line_irq_handler(int irq, void *priv)
{
	struct stfcamss *stfcamss = priv;
	struct stf_capture *cap = &stfcamss->captures[STF_CAPTURE_YUV];
	u32 status;

	status = stf_isp_reg_read(stfcamss, ISP_REG_ISP_CTRL_0);
	if (status & ISPC_LINE) {
		if (atomic_dec_if_positive(&cap->buffers.frame_skip) < 0) {
			if ((status & ISPC_ENUO))
				stf_change_buffer(&cap->buffers);
		}

		stf_isp_reg_set_bit(stfcamss, ISP_REG_CSIINTS,
				    CSI_INTS_MASK, CSI_INTS(0x3));
		stf_isp_reg_set_bit(stfcamss, ISP_REG_IESHD,
				    SHAD_UP_M | SHAD_UP_EN, 0x3);

		stf_isp_reg_write(stfcamss, ISP_REG_ISP_CTRL_0,
				  (status & ~ISPC_INT_ALL_MASK) | ISPC_LINE);
	}

	return IRQ_HANDLED;
}

static int stf_queue_buffer(struct stfcamss_video *video,
			    struct stfcamss_buffer *buf)
{
	struct stf_capture *cap = to_stf_capture(video);
	struct stf_v_buf *v_bufs = &cap->buffers;
	unsigned long flags;

	spin_lock_irqsave(&v_bufs->lock, flags);
	stf_buf_update_on_new(video, buf);
	spin_unlock_irqrestore(&v_bufs->lock, flags);

	return 0;
}

static int stf_flush_buffers(struct stfcamss_video *video,
			     enum vb2_buffer_state state)
{
	struct stf_capture *cap = to_stf_capture(video);
	struct stf_v_buf *v_bufs = &cap->buffers;
	unsigned long flags;
	unsigned int i;

	spin_lock_irqsave(&v_bufs->lock, flags);

	stf_buf_flush(v_bufs, state);

	for (i = 0; i < ARRAY_SIZE(v_bufs->buf); i++) {
		if (v_bufs->buf[i])
			vb2_buffer_done(&v_bufs->buf[i]->vb.vb2_buf, state);

		v_bufs->buf[i] = NULL;
	}

	if (v_bufs->last_buffer) {
		vb2_buffer_done(&v_bufs->last_buffer->vb.vb2_buf, state);
		v_bufs->last_buffer = NULL;
	}

	spin_unlock_irqrestore(&v_bufs->lock, flags);
	return 0;
}

static const struct stfcamss_video_ops stf_capture_ops = {
	.queue_buffer = stf_queue_buffer,
	.flush_buffers = stf_flush_buffers,
	.start_streaming = stf_capture_start,
	.stop_streaming = stf_capture_stop,
};

static void stf_capture_unregister_one(struct stf_capture *cap)
{
	if (!video_is_registered(&cap->video.vdev))
		return;

	media_entity_cleanup(&cap->video.vdev.entity);
	vb2_video_unregister_device(&cap->video.vdev);
}

void stf_capture_unregister(struct stfcamss *stfcamss)
{
	struct stf_capture *cap_raw = &stfcamss->captures[STF_CAPTURE_RAW];
	struct stf_capture *cap_yuv = &stfcamss->captures[STF_CAPTURE_YUV];

	stf_capture_unregister_one(cap_raw);
	stf_capture_unregister_one(cap_yuv);
}

int stf_capture_register(struct stfcamss *stfcamss,
			 struct v4l2_device *v4l2_dev)
{
	unsigned int i;
	int ret;

	for (i = 0; i < ARRAY_SIZE(stfcamss->captures); i++) {
		struct stf_capture *capture = &stfcamss->captures[i];

		capture->type = i;
		capture->video.ops = &stf_capture_ops;
		stf_capture_init(stfcamss, capture);

		ret = stf_video_register(&capture->video, v4l2_dev,
					 stf_cap_names[i]);
		if (ret < 0) {
			dev_err(stfcamss->dev,
				"Failed to register video node: %d\n", ret);
			stf_capture_unregister(stfcamss);
			return ret;
		}
	}

	return 0;
}