// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * s3c24xx/s3c64xx SoC series Camera Interface (CAMIF) driver
 *
 * Copyright (C) 2012 Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
 * Copyright (C) 2012 Tomasz Figa <tomasz.figa@gmail.com>
 */
#define pr_fmt(fmt) "%s:%d " fmt, __func__, __LINE__

#include <linux/bug.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/gpio.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/types.h>

#include <media/media-device.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-ioctl.h>
#include <media/videobuf2-v4l2.h>
#include <media/videobuf2-dma-contig.h>

#include "camif-core.h"

static char *camif_clocks[CLK_MAX_NUM] = {
        /* HCLK CAMIF clock */
        [CLK_GATE]      = "camif",
        /* CAMIF / external camera sensor master clock */
        [CLK_CAM]       = "camera",
};

static const struct camif_fmt camif_formats[] = {
        {
                .fourcc         = V4L2_PIX_FMT_YUV422P,
                .depth          = 16,
                .ybpp           = 1,
                .color          = IMG_FMT_YCBCR422P,
                .colplanes      = 3,
                .flags          = FMT_FL_S3C24XX_CODEC |
                                  FMT_FL_S3C64XX,
        }, {
                .fourcc         = V4L2_PIX_FMT_YUV420,
                .depth          = 12,
                .ybpp           = 1,
                .color          = IMG_FMT_YCBCR420,
                .colplanes      = 3,
                .flags          = FMT_FL_S3C24XX_CODEC |
                                  FMT_FL_S3C64XX,
        }, {
                .fourcc         = V4L2_PIX_FMT_YVU420,
                .depth          = 12,
                .ybpp           = 1,
                .color          = IMG_FMT_YCRCB420,
                .colplanes      = 3,
                .flags          = FMT_FL_S3C24XX_CODEC |
                                  FMT_FL_S3C64XX,
        }, {
                .fourcc         = V4L2_PIX_FMT_RGB565X,
                .depth          = 16,
                .ybpp           = 2,
                .color          = IMG_FMT_RGB565,
                .colplanes      = 1,
                .flags          = FMT_FL_S3C24XX_PREVIEW |
                                  FMT_FL_S3C64XX,
        }, {
                .fourcc         = V4L2_PIX_FMT_RGB32,
                .depth          = 32,
                .ybpp           = 4,
                .color          = IMG_FMT_XRGB8888,
                .colplanes      = 1,
                .flags          = FMT_FL_S3C24XX_PREVIEW |
                                  FMT_FL_S3C64XX,
        }, {
                .fourcc         = V4L2_PIX_FMT_BGR666,
                .depth          = 32,
                .ybpp           = 4,
                .color          = IMG_FMT_RGB666,
                .colplanes      = 1,
                .flags          = FMT_FL_S3C64XX,
        }
};

/**
 * s3c_camif_find_format() - lookup camif color format by fourcc or an index
 * @vp: video path (DMA) description (codec/preview)
 * @pixelformat: fourcc to match, ignored if null
 * @index: index to the camif_formats array, ignored if negative
 */
const struct camif_fmt *s3c_camif_find_format(struct camif_vp *vp,
                                              const u32 *pixelformat,
                                              int index)
{
        const struct camif_fmt *fmt, *def_fmt = NULL;
        unsigned int i;
        int id = 0;

        if (index >= (int)ARRAY_SIZE(camif_formats))
                return NULL;

        for (i = 0; i < ARRAY_SIZE(camif_formats); ++i) {
                fmt = &camif_formats[i];
                if (vp && !(vp->fmt_flags & fmt->flags))
                        continue;
                if (pixelformat && fmt->fourcc == *pixelformat)
                        return fmt;
                if (index == id)
                        def_fmt = fmt;
                id++;
        }
        return def_fmt;
}

static int camif_get_scaler_factor(u32 src, u32 tar, u32 *ratio, u32 *shift)
{
        unsigned int sh = 6;

        if (src >= 64 * tar)
                return -EINVAL;

        while (sh--) {
                unsigned int tmp = 1 << sh;
                if (src >= tar * tmp) {
                        *shift = sh;
                        *ratio = tmp;
                        return 0;
                }
        }
        *shift = 0;
        *ratio = 1;
        return 0;
}

int s3c_camif_get_scaler_config(struct camif_vp *vp,
                                struct camif_scaler *scaler)
{
        struct v4l2_rect *camif_crop = &vp->camif->camif_crop;
        int source_x = camif_crop->width;
        int source_y = camif_crop->height;
        int target_x = vp->out_frame.rect.width;
        int target_y = vp->out_frame.rect.height;
        int ret;

        if (vp->rotation == 90 || vp->rotation == 270)
                swap(target_x, target_y);

        ret = camif_get_scaler_factor(source_x, target_x, &scaler->pre_h_ratio,
                                      &scaler->h_shift);
        if (ret < 0)
                return ret;

        ret = camif_get_scaler_factor(source_y, target_y, &scaler->pre_v_ratio,
                                      &scaler->v_shift);
        if (ret < 0)
                return ret;

        scaler->pre_dst_width = source_x / scaler->pre_h_ratio;
        scaler->pre_dst_height = source_y / scaler->pre_v_ratio;

        scaler->main_h_ratio = (source_x << 8) / (target_x << scaler->h_shift);
        scaler->main_v_ratio = (source_y << 8) / (target_y << scaler->v_shift);

        scaler->scaleup_h = (target_x >= source_x);
        scaler->scaleup_v = (target_y >= source_y);

        scaler->copy = 0;

        pr_debug("H: ratio: %u, shift: %u. V: ratio: %u, shift: %u.\n",
                 scaler->pre_h_ratio, scaler->h_shift,
                 scaler->pre_v_ratio, scaler->v_shift);

        pr_debug("Source: %dx%d, Target: %dx%d, scaleup_h/v: %d/%d\n",
                 source_x, source_y, target_x, target_y,
                 scaler->scaleup_h, scaler->scaleup_v);

        return 0;
}

static int camif_register_sensor(struct camif_dev *camif)
{
        struct s3c_camif_sensor_info *sensor = &camif->pdata.sensor;
        struct v4l2_device *v4l2_dev = &camif->v4l2_dev;
        struct i2c_adapter *adapter;
        struct v4l2_subdev_format format = {
                .which = V4L2_SUBDEV_FORMAT_ACTIVE,
        };
        struct v4l2_subdev *sd;
        int ret;

        camif->sensor.sd = NULL;

        if (sensor->i2c_board_info.addr == 0)
                return -EINVAL;

        adapter = i2c_get_adapter(sensor->i2c_bus_num);
        if (adapter == NULL) {
                v4l2_warn(v4l2_dev, "failed to get I2C adapter %d\n",
                          sensor->i2c_bus_num);
                return -EPROBE_DEFER;
        }

        sd = v4l2_i2c_new_subdev_board(v4l2_dev, adapter,
                                       &sensor->i2c_board_info, NULL);
        if (sd == NULL) {
                i2c_put_adapter(adapter);
                v4l2_warn(v4l2_dev, "failed to acquire subdev %s\n",
                          sensor->i2c_board_info.type);
                return -EPROBE_DEFER;
        }
        camif->sensor.sd = sd;

        v4l2_info(v4l2_dev, "registered sensor subdevice %s\n", sd->name);

        /* Get initial pixel format and set it at the camif sink pad */
        format.pad = 0;
        ret = v4l2_subdev_call(sd, pad, get_fmt, NULL, &format);

        if (ret < 0)
                return 0;

        format.pad = CAMIF_SD_PAD_SINK;
        v4l2_subdev_call(&camif->subdev, pad, set_fmt, NULL, &format);

        v4l2_info(sd, "Initial format from sensor: %dx%d, %#x\n",
                  format.format.width, format.format.height,
                  format.format.code);
        return 0;
}

static void camif_unregister_sensor(struct camif_dev *camif)
{
        struct v4l2_subdev *sd = camif->sensor.sd;
        struct i2c_client *client = sd ? v4l2_get_subdevdata(sd) : NULL;
        struct i2c_adapter *adapter;

        if (client == NULL)
                return;

        adapter = client->adapter;
        v4l2_device_unregister_subdev(sd);
        camif->sensor.sd = NULL;
        i2c_unregister_device(client);
        i2c_put_adapter(adapter);
}

static int camif_create_media_links(struct camif_dev *camif)
{
        int i, ret;

        ret = media_create_pad_link(&camif->sensor.sd->entity, 0,
                                &camif->subdev.entity, CAMIF_SD_PAD_SINK,
                                MEDIA_LNK_FL_IMMUTABLE |
                                MEDIA_LNK_FL_ENABLED);
        if (ret)
                return ret;

        for (i = 1; i < CAMIF_SD_PADS_NUM && !ret; i++) {
                ret = media_create_pad_link(&camif->subdev.entity, i,
                                &camif->vp[i - 1].vdev.entity, 0,
                                MEDIA_LNK_FL_IMMUTABLE |
                                MEDIA_LNK_FL_ENABLED);
        }

        return ret;
}

static int camif_register_video_nodes(struct camif_dev *camif)
{
        int ret = s3c_camif_register_video_node(camif, VP_CODEC);
        if (ret < 0)
                return ret;

        return s3c_camif_register_video_node(camif, VP_PREVIEW);
}

static void camif_unregister_video_nodes(struct camif_dev *camif)
{
        s3c_camif_unregister_video_node(camif, VP_CODEC);
        s3c_camif_unregister_video_node(camif, VP_PREVIEW);
}

static void camif_unregister_media_entities(struct camif_dev *camif)
{
        camif_unregister_video_nodes(camif);
        camif_unregister_sensor(camif);
}

/*
 * Media device
 */
static int camif_media_dev_init(struct camif_dev *camif)
{
        struct media_device *md = &camif->media_dev;
        struct v4l2_device *v4l2_dev = &camif->v4l2_dev;
        unsigned int ip_rev = camif->variant->ip_revision;
        int ret;

        memset(md, 0, sizeof(*md));
        snprintf(md->model, sizeof(md->model), "Samsung S3C%s CAMIF",
                 ip_rev == S3C6410_CAMIF_IP_REV ? "6410" : "244X");
        strscpy(md->bus_info, "platform", sizeof(md->bus_info));
        md->hw_revision = ip_rev;

        md->dev = camif->dev;

        strscpy(v4l2_dev->name, "s3c-camif", sizeof(v4l2_dev->name));
        v4l2_dev->mdev = md;

        media_device_init(md);

        ret = v4l2_device_register(camif->dev, v4l2_dev);
        if (ret < 0)
                return ret;

        return ret;
}

static void camif_clk_put(struct camif_dev *camif)
{
        int i;

        for (i = 0; i < CLK_MAX_NUM; i++) {
                if (IS_ERR(camif->clock[i]))
                        continue;
                clk_unprepare(camif->clock[i]);
                clk_put(camif->clock[i]);
                camif->clock[i] = ERR_PTR(-EINVAL);
        }
}

static int camif_clk_get(struct camif_dev *camif)
{
        int ret, i;

        for (i = 1; i < CLK_MAX_NUM; i++)
                camif->clock[i] = ERR_PTR(-EINVAL);

        for (i = 0; i < CLK_MAX_NUM; i++) {
                camif->clock[i] = clk_get(camif->dev, camif_clocks[i]);
                if (IS_ERR(camif->clock[i])) {
                        ret = PTR_ERR(camif->clock[i]);
                        goto err;
                }
                ret = clk_prepare(camif->clock[i]);
                if (ret < 0) {
                        clk_put(camif->clock[i]);
                        camif->clock[i] = NULL;
                        goto err;
                }
        }
        return 0;
err:
        camif_clk_put(camif);
        dev_err(camif->dev, "failed to get clock: %s\n",
                camif_clocks[i]);
        return ret;
}

/*
 * The CAMIF device has two relatively independent data processing paths
 * that can source data from memory or the common camera input frontend.
 * Register interrupts for each data processing path (camif_vp).
 */
static int camif_request_irqs(struct platform_device *pdev,
                              struct camif_dev *camif)
{
        int irq, ret, i;

        for (i = 0; i < CAMIF_VP_NUM; i++) {
                struct camif_vp *vp = &camif->vp[i];

                init_waitqueue_head(&vp->irq_queue);

                irq = platform_get_irq(pdev, i);
                if (irq < 0)
                        return irq;

                ret = devm_request_irq(&pdev->dev, irq, s3c_camif_irq_handler,
                                       0, dev_name(&pdev->dev), vp);
                if (ret < 0) {
                        dev_err(&pdev->dev, "failed to install IRQ: %d\n", ret);
                        break;
                }
        }

        return ret;
}

static int s3c_camif_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct s3c_camif_plat_data *pdata = dev->platform_data;
        struct s3c_camif_drvdata *drvdata;
        struct camif_dev *camif;
        int ret = 0;

        camif = devm_kzalloc(dev, sizeof(*camif), GFP_KERNEL);
        if (!camif)
                return -ENOMEM;

        spin_lock_init(&camif->slock);
        mutex_init(&camif->lock);

        camif->dev = dev;

        if (!pdata || !pdata->gpio_get || !pdata->gpio_put) {
                dev_err(dev, "wrong platform data\n");
                return -EINVAL;
        }

        camif->pdata = *pdata;
        drvdata = (void *)platform_get_device_id(pdev)->driver_data;
        camif->variant = drvdata->variant;

        camif->io_base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(camif->io_base))
                return PTR_ERR(camif->io_base);

        ret = camif_request_irqs(pdev, camif);
        if (ret < 0)
                return ret;

        ret = pdata->gpio_get();
        if (ret < 0)
                return ret;

        ret = s3c_camif_create_subdev(camif);
        if (ret < 0)
                goto err_sd;

        ret = camif_clk_get(camif);
        if (ret < 0)
                goto err_clk;

        platform_set_drvdata(pdev, camif);
        clk_set_rate(camif->clock[CLK_CAM],
                        camif->pdata.sensor.clock_frequency);

        dev_info(dev, "sensor clock frequency: %lu\n",
                 clk_get_rate(camif->clock[CLK_CAM]));
        /*
         * Set initial pixel format, resolution and crop rectangle.
         * Must be done before a sensor subdev is registered as some
         * settings are overrode with values from sensor subdev.
         */
        s3c_camif_set_defaults(camif);

        pm_runtime_enable(dev);

        ret = pm_runtime_resume_and_get(dev);
        if (ret < 0)
                goto err_disable;

        ret = camif_media_dev_init(camif);
        if (ret < 0)
                goto err_pm;

        ret = camif_register_sensor(camif);
        if (ret < 0)
                goto err_sens;

        ret = v4l2_device_register_subdev(&camif->v4l2_dev, &camif->subdev);
        if (ret < 0)
                goto err_sens;

        ret = v4l2_device_register_subdev_nodes(&camif->v4l2_dev);
        if (ret < 0)
                goto err_sens;

        ret = camif_register_video_nodes(camif);
        if (ret < 0)
                goto err_sens;

        ret = camif_create_media_links(camif);
        if (ret < 0)
                goto err_sens;

        ret = media_device_register(&camif->media_dev);
        if (ret < 0)
                goto err_sens;

        pm_runtime_put(dev);
        return 0;

err_sens:
        v4l2_device_unregister(&camif->v4l2_dev);
        media_device_unregister(&camif->media_dev);
        media_device_cleanup(&camif->media_dev);
        camif_unregister_media_entities(camif);
err_pm:
        pm_runtime_put(dev);
err_disable:
        pm_runtime_disable(dev);
        camif_clk_put(camif);
err_clk:
        s3c_camif_unregister_subdev(camif);
err_sd:
        pdata->gpio_put();
        return ret;
}

static void s3c_camif_remove(struct platform_device *pdev)
{
        struct camif_dev *camif = platform_get_drvdata(pdev);
        struct s3c_camif_plat_data *pdata = &camif->pdata;

        media_device_unregister(&camif->media_dev);
        media_device_cleanup(&camif->media_dev);
        camif_unregister_media_entities(camif);
        v4l2_device_unregister(&camif->v4l2_dev);

        pm_runtime_disable(&pdev->dev);
        camif_clk_put(camif);
        s3c_camif_unregister_subdev(camif);
        pdata->gpio_put();
}

static int s3c_camif_runtime_resume(struct device *dev)
{
        struct camif_dev *camif = dev_get_drvdata(dev);
        int ret;

        ret = clk_enable(camif->clock[CLK_GATE]);
        if (ret)
                return ret;

        /* null op on s3c244x */
        ret = clk_enable(camif->clock[CLK_CAM]);
        if (ret) {
                clk_disable(camif->clock[CLK_GATE]);
                return ret;
        }

        return 0;
}

static int s3c_camif_runtime_suspend(struct device *dev)
{
        struct camif_dev *camif = dev_get_drvdata(dev);

        /* null op on s3c244x */
        clk_disable(camif->clock[CLK_CAM]);

        clk_disable(camif->clock[CLK_GATE]);
        return 0;
}

static const struct s3c_camif_variant s3c244x_camif_variant = {
        .vp_pix_limits = {
                [VP_CODEC] = {
                        .max_out_width          = 4096,
                        .max_sc_out_width       = 2048,
                        .out_width_align        = 16,
                        .min_out_width          = 16,
                        .max_height             = 4096,
                },
                [VP_PREVIEW] = {
                        .max_out_width          = 640,
                        .max_sc_out_width       = 640,
                        .out_width_align        = 16,
                        .min_out_width          = 16,
                        .max_height             = 480,
                }
        },
        .pix_limits = {
                .win_hor_offset_align   = 8,
        },
        .ip_revision = S3C244X_CAMIF_IP_REV,
};

static struct s3c_camif_drvdata s3c244x_camif_drvdata = {
        .variant        = &s3c244x_camif_variant,
        .bus_clk_freq   = 24000000UL,
};

static const struct s3c_camif_variant s3c6410_camif_variant = {
        .vp_pix_limits = {
                [VP_CODEC] = {
                        .max_out_width          = 4096,
                        .max_sc_out_width       = 2048,
                        .out_width_align        = 16,
                        .min_out_width          = 16,
                        .max_height             = 4096,
                },
                [VP_PREVIEW] = {
                        .max_out_width          = 4096,
                        .max_sc_out_width       = 720,
                        .out_width_align        = 16,
                        .min_out_width          = 16,
                        .max_height             = 4096,
                }
        },
        .pix_limits = {
                .win_hor_offset_align   = 8,
        },
        .ip_revision = S3C6410_CAMIF_IP_REV,
        .has_img_effect = 1,
        .vp_offset = 0x20,
};

static struct s3c_camif_drvdata s3c6410_camif_drvdata = {
        .variant        = &s3c6410_camif_variant,
        .bus_clk_freq   = 133000000UL,
};

static const struct platform_device_id s3c_camif_driver_ids[] = {
        {
                .name           = "s3c2440-camif",
                .driver_data    = (unsigned long)&s3c244x_camif_drvdata,
        }, {
                .name           = "s3c6410-camif",
                .driver_data    = (unsigned long)&s3c6410_camif_drvdata,
        },
        { /* sentinel */ },
};
MODULE_DEVICE_TABLE(platform, s3c_camif_driver_ids);

static const struct dev_pm_ops s3c_camif_pm_ops = {
        .runtime_suspend        = s3c_camif_runtime_suspend,
        .runtime_resume         = s3c_camif_runtime_resume,
};

static struct platform_driver s3c_camif_driver = {
        .probe          = s3c_camif_probe,
        .remove         = s3c_camif_remove,
        .id_table       = s3c_camif_driver_ids,
        .driver = {
                .name   = S3C_CAMIF_DRIVER_NAME,
                .pm     = &s3c_camif_pm_ops,
        }
};

module_platform_driver(s3c_camif_driver);

MODULE_AUTHOR("Sylwester Nawrocki <sylvester.nawrocki@gmail.com>");
MODULE_AUTHOR("Tomasz Figa <tomasz.figa@gmail.com>");
MODULE_DESCRIPTION("S3C24XX/S3C64XX SoC camera interface driver");
MODULE_LICENSE("GPL");