// SPDX-License-Identifier: GPL-2.0
/*
 * Support for Medifield PNW Camera Imaging ISP subsystem.
 *
 * Copyright (c) 2010 Intel Corporation. All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 as published by the Free Software Foundation.
 *
 * This program 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.
 *
 *
 */

#include <media/v4l2-event.h>
#include <media/v4l2-mediabus.h>
#include "atomisp_cmd.h"
#include "atomisp_internal.h"
#include "atomisp-regs.h"

static struct
v4l2_mbus_framefmt *__csi2_get_format(struct atomisp_mipi_csi2_device *csi2,
				      struct v4l2_subdev_state *sd_state,
				      enum v4l2_subdev_format_whence which,
				      unsigned int pad)
{
	if (which == V4L2_SUBDEV_FORMAT_TRY)
		return v4l2_subdev_get_try_format(&csi2->subdev, sd_state,
						  pad);
	else
		return &csi2->formats[pad];
}

/*
 * csi2_enum_mbus_code - Handle pixel format enumeration
 * @sd     : pointer to v4l2 subdev structure
 * @fh     : V4L2 subdev file handle
 * @code   : pointer to v4l2_subdev_pad_mbus_code_enum structure
 * return -EINVAL or zero on success
 */
static int csi2_enum_mbus_code(struct v4l2_subdev *sd,
			       struct v4l2_subdev_state *sd_state,
			       struct v4l2_subdev_mbus_code_enum *code)
{
	const struct atomisp_in_fmt_conv *ic = atomisp_in_fmt_conv;
	unsigned int i = 0;

	while (ic->code) {
		if (i == code->index) {
			code->code = ic->code;
			return 0;
		}
		i++, ic++;
	}

	return -EINVAL;
}

/*
 * csi2_get_format - Handle get format by pads subdev method
 * @sd : pointer to v4l2 subdev structure
 * @fh : V4L2 subdev file handle
 * @pad: pad num
 * @fmt: pointer to v4l2 format structure
 * return -EINVAL or zero on success
 */
static int csi2_get_format(struct v4l2_subdev *sd,
			   struct v4l2_subdev_state *sd_state,
			   struct v4l2_subdev_format *fmt)
{
	struct atomisp_mipi_csi2_device *csi2 = v4l2_get_subdevdata(sd);
	struct v4l2_mbus_framefmt *format;

	format = __csi2_get_format(csi2, sd_state, fmt->which, fmt->pad);

	fmt->format = *format;

	return 0;
}

int atomisp_csi2_set_ffmt(struct v4l2_subdev *sd,
			  struct v4l2_subdev_state *sd_state,
			  unsigned int which, uint16_t pad,
			  struct v4l2_mbus_framefmt *ffmt)
{
	struct atomisp_mipi_csi2_device *csi2 = v4l2_get_subdevdata(sd);
	struct v4l2_mbus_framefmt *actual_ffmt = __csi2_get_format(csi2,
								   sd_state,
								   which, pad);

	if (pad == CSI2_PAD_SINK) {
		const struct atomisp_in_fmt_conv *ic;
		struct v4l2_mbus_framefmt tmp_ffmt;

		ic = atomisp_find_in_fmt_conv(ffmt->code);
		if (ic)
			actual_ffmt->code = ic->code;
		else
			actual_ffmt->code = atomisp_in_fmt_conv[0].code;

		actual_ffmt->width = clamp_t(u32, ffmt->width,
					     ATOM_ISP_MIN_WIDTH,
					     ATOM_ISP_MAX_WIDTH);
		actual_ffmt->height = clamp_t(u32, ffmt->height,
					      ATOM_ISP_MIN_HEIGHT,
					      ATOM_ISP_MAX_HEIGHT);

		tmp_ffmt = *ffmt = *actual_ffmt;

		return atomisp_csi2_set_ffmt(sd, sd_state, which,
					     CSI2_PAD_SOURCE,
					     &tmp_ffmt);
	}

	/* FIXME: DPCM decompression */
	*actual_ffmt = *ffmt = *__csi2_get_format(csi2, sd_state, which,
						  CSI2_PAD_SINK);

	return 0;
}

/*
 * csi2_set_format - Handle set format by pads subdev method
 * @sd : pointer to v4l2 subdev structure
 * @fh : V4L2 subdev file handle
 * @pad: pad num
 * @fmt: pointer to v4l2 format structure
 * return -EINVAL or zero on success
 */
static int csi2_set_format(struct v4l2_subdev *sd,
			   struct v4l2_subdev_state *sd_state,
			   struct v4l2_subdev_format *fmt)
{
	return atomisp_csi2_set_ffmt(sd, sd_state, fmt->which, fmt->pad,
				     &fmt->format);
}

/*
 * csi2_set_stream - Enable/Disable streaming on the CSI2 module
 * @sd: ISP CSI2 V4L2 subdevice
 * @enable: Enable/disable stream (1/0)
 *
 * Return 0 on success or a negative error code otherwise.
 */
static int csi2_set_stream(struct v4l2_subdev *sd, int enable)
{
	return 0;
}

/* subdev core operations */
static const struct v4l2_subdev_core_ops csi2_core_ops = {
};

/* subdev video operations */
static const struct v4l2_subdev_video_ops csi2_video_ops = {
	.s_stream = csi2_set_stream,
};

/* subdev pad operations */
static const struct v4l2_subdev_pad_ops csi2_pad_ops = {
	.enum_mbus_code = csi2_enum_mbus_code,
	.get_fmt = csi2_get_format,
	.set_fmt = csi2_set_format,
	.link_validate = v4l2_subdev_link_validate_default,
};

/* subdev operations */
static const struct v4l2_subdev_ops csi2_ops = {
	.core = &csi2_core_ops,
	.video = &csi2_video_ops,
	.pad = &csi2_pad_ops,
};

/*
 * csi2_link_setup - Setup CSI2 connections.
 * @entity : Pointer to media entity structure
 * @local  : Pointer to local pad array
 * @remote : Pointer to remote pad array
 * @flags  : Link flags
 * return -EINVAL or zero on success
 */
static int csi2_link_setup(struct media_entity *entity,
			   const struct media_pad *local,
			   const struct media_pad *remote, u32 flags)
{
	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
	struct atomisp_mipi_csi2_device *csi2 = v4l2_get_subdevdata(sd);
	u32 result = local->index | is_media_entity_v4l2_subdev(remote->entity);

	switch (result) {
	case CSI2_PAD_SOURCE | MEDIA_ENT_F_OLD_BASE:
		/* not supported yet */
		return -EINVAL;

	case CSI2_PAD_SOURCE | MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN:
		if (flags & MEDIA_LNK_FL_ENABLED) {
			if (csi2->output & ~CSI2_OUTPUT_ISP_SUBDEV)
				return -EBUSY;
			csi2->output |= CSI2_OUTPUT_ISP_SUBDEV;
		} else {
			csi2->output &= ~CSI2_OUTPUT_ISP_SUBDEV;
		}
		break;

	default:
		/* Link from camera to CSI2 is fixed... */
		return -EINVAL;
	}
	return 0;
}

/* media operations */
static const struct media_entity_operations csi2_media_ops = {
	.link_setup = csi2_link_setup,
	.link_validate = v4l2_subdev_link_validate,
};

/*
 * ispcsi2_init_entities - Initialize subdev and media entity.
 * @csi2: Pointer to ispcsi2 structure.
 * return -ENOMEM or zero on success
 */
static int mipi_csi2_init_entities(struct atomisp_mipi_csi2_device *csi2,
				   int port)
{
	struct v4l2_subdev *sd = &csi2->subdev;
	struct media_pad *pads = csi2->pads;
	struct media_entity *me = &sd->entity;
	int ret;

	v4l2_subdev_init(sd, &csi2_ops);
	snprintf(sd->name, sizeof(sd->name), "ATOM ISP CSI2-port%d", port);

	v4l2_set_subdevdata(sd, csi2);
	sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;

	pads[CSI2_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
	pads[CSI2_PAD_SINK].flags = MEDIA_PAD_FL_SINK;

	me->ops = &csi2_media_ops;
	me->function = MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN;
	ret = media_entity_pads_init(me, CSI2_PADS_NUM, pads);
	if (ret < 0)
		return ret;

	csi2->formats[CSI2_PAD_SINK].code = atomisp_in_fmt_conv[0].code;
	csi2->formats[CSI2_PAD_SOURCE].code = atomisp_in_fmt_conv[0].code;

	return 0;
}

void
atomisp_mipi_csi2_unregister_entities(struct atomisp_mipi_csi2_device *csi2)
{
	media_entity_cleanup(&csi2->subdev.entity);
	v4l2_device_unregister_subdev(&csi2->subdev);
}

int atomisp_mipi_csi2_register_entities(struct atomisp_mipi_csi2_device *csi2,
					struct v4l2_device *vdev)
{
	int ret;

	/* Register the subdev and video nodes. */
	ret = v4l2_device_register_subdev(vdev, &csi2->subdev);
	if (ret < 0)
		goto error;

	return 0;

error:
	atomisp_mipi_csi2_unregister_entities(csi2);
	return ret;
}

static const int LIMIT_SHIFT = 6;	/* Limit numeric range into 31 bits */

static int
atomisp_csi2_configure_calc(const short int coeffs[2], int mipi_freq, int def)
{
	/* Delay counter accuracy, 1/0.0625 for ANN/CHT, 1/0.125 for BXT */
	static const int accinv = 16;		/* 1 / COUNT_ACC */
	int r;

	if (mipi_freq >> LIMIT_SHIFT <= 0)
		return def;

	r = accinv * coeffs[1] * (500000000 >> LIMIT_SHIFT);
	r /= mipi_freq >> LIMIT_SHIFT;
	r += accinv * coeffs[0];

	return r;
}

static void atomisp_csi2_configure_isp2401(struct atomisp_sub_device *asd)
{
	/*
	 * The ISP2401 new input system CSI2+ receiver has several
	 * parameters affecting the receiver timings. These depend
	 * on the MIPI bus frequency F in Hz (sensor transmitter rate)
	 * as follows:
	 *	register value = (A/1e9 + B * UI) / COUNT_ACC
	 * where
	 *	UI = 1 / (2 * F) in seconds
	 *	COUNT_ACC = counter accuracy in seconds
	 *	For ANN and CHV, COUNT_ACC = 0.0625 ns
	 *	For BXT,  COUNT_ACC = 0.125 ns
	 * A and B are coefficients from the table below,
	 * depending whether the register minimum or maximum value is
	 * calculated.
	 *				       Minimum     Maximum
	 * Clock lane			       A     B     A     B
	 * reg_rx_csi_dly_cnt_termen_clane     0     0    38     0
	 * reg_rx_csi_dly_cnt_settle_clane    95    -8   300   -16
	 * Data lanes
	 * reg_rx_csi_dly_cnt_termen_dlane0    0     0    35     4
	 * reg_rx_csi_dly_cnt_settle_dlane0   85    -2   145    -6
	 * reg_rx_csi_dly_cnt_termen_dlane1    0     0    35     4
	 * reg_rx_csi_dly_cnt_settle_dlane1   85    -2   145    -6
	 * reg_rx_csi_dly_cnt_termen_dlane2    0     0    35     4
	 * reg_rx_csi_dly_cnt_settle_dlane2   85    -2   145    -6
	 * reg_rx_csi_dly_cnt_termen_dlane3    0     0    35     4
	 * reg_rx_csi_dly_cnt_settle_dlane3   85    -2   145    -6
	 *
	 * We use the minimum values in the calculations below.
	 */
	static const short int coeff_clk_termen[] = { 0, 0 };
	static const short int coeff_clk_settle[] = { 95, -8 };
	static const short int coeff_dat_termen[] = { 0, 0 };
	static const short int coeff_dat_settle[] = { 85, -2 };
	static const int TERMEN_DEFAULT		  = 0 * 0;
	static const int SETTLE_DEFAULT		  = 0x480;

	static const hrt_address csi2_port_base[] = {
		[ATOMISP_CAMERA_PORT_PRIMARY]     = CSI2_PORT_A_BASE,
		[ATOMISP_CAMERA_PORT_SECONDARY]   = CSI2_PORT_B_BASE,
		[ATOMISP_CAMERA_PORT_TERTIARY]    = CSI2_PORT_C_BASE,
	};
	/* Number of lanes on each port, excluding clock lane */
	static const unsigned char csi2_port_lanes[] = {
		[ATOMISP_CAMERA_PORT_PRIMARY]     = 4,
		[ATOMISP_CAMERA_PORT_SECONDARY]   = 2,
		[ATOMISP_CAMERA_PORT_TERTIARY]    = 2,
	};
	static const hrt_address csi2_lane_base[] = {
		CSI2_LANE_CL_BASE,
		CSI2_LANE_D0_BASE,
		CSI2_LANE_D1_BASE,
		CSI2_LANE_D2_BASE,
		CSI2_LANE_D3_BASE,
	};

	int clk_termen;
	int clk_settle;
	int dat_termen;
	int dat_settle;

	struct v4l2_control ctrl;
	struct atomisp_device *isp = asd->isp;
	struct camera_mipi_info *mipi_info;
	int mipi_freq = 0;
	enum atomisp_camera_port port;

	int n;

	mipi_info = atomisp_to_sensor_mipi_info(
			isp->inputs[asd->input_curr].camera);
	port = mipi_info->port;

	ctrl.id = V4L2_CID_LINK_FREQ;
	if (v4l2_g_ctrl
	    (isp->inputs[asd->input_curr].camera->ctrl_handler, &ctrl) == 0)
		mipi_freq = ctrl.value;

	clk_termen = atomisp_csi2_configure_calc(coeff_clk_termen, mipi_freq,
						 TERMEN_DEFAULT);
	clk_settle = atomisp_csi2_configure_calc(coeff_clk_settle, mipi_freq,
						 SETTLE_DEFAULT);
	dat_termen = atomisp_csi2_configure_calc(coeff_dat_termen, mipi_freq,
						 TERMEN_DEFAULT);
	dat_settle = atomisp_csi2_configure_calc(coeff_dat_settle, mipi_freq,
						 SETTLE_DEFAULT);

	for (n = 0; n < csi2_port_lanes[port] + 1; n++) {
		hrt_address base = csi2_port_base[port] + csi2_lane_base[n];

		atomisp_css2_hw_store_32(base + CSI2_REG_RX_CSI_DLY_CNT_TERMEN,
					 n == 0 ? clk_termen : dat_termen);
		atomisp_css2_hw_store_32(base + CSI2_REG_RX_CSI_DLY_CNT_SETTLE,
					 n == 0 ? clk_settle : dat_settle);
	}
}

void atomisp_csi2_configure(struct atomisp_sub_device *asd)
{
	if (IS_HWREVISION(asd->isp, ATOMISP_HW_REVISION_ISP2401))
		atomisp_csi2_configure_isp2401(asd);
}

/*
 * atomisp_mipi_csi2_cleanup - Routine for module driver cleanup
 */
void atomisp_mipi_csi2_cleanup(struct atomisp_device *isp)
{
}

int atomisp_mipi_csi2_init(struct atomisp_device *isp)
{
	struct atomisp_mipi_csi2_device *csi2_port;
	unsigned int i;
	int ret;

	for (i = 0; i < ATOMISP_CAMERA_NR_PORTS; i++) {
		csi2_port = &isp->csi2_port[i];
		csi2_port->isp = isp;
		ret = mipi_csi2_init_entities(csi2_port, i);
		if (ret < 0)
			goto fail;
	}

	return 0;

fail:
	atomisp_mipi_csi2_cleanup(isp);
	return ret;
}