// SPDX-License-Identifier: GPL-2.0
/*
 * Support for T4KA3 8M camera sensor.
 *
 * Copyright (C) 2015 Intel Corporation. All Rights Reserved.
 * Copyright (C) 2016 XiaoMi, Inc.
 * Copyright (C) 2024 Hans de Goede <hansg@kernel.org>
 * Copyright (C) 2026 Kate Hsuan <hpa@redhat.com>
 */

#include <linux/acpi.h>
#include <linux/bits.h>
#include <linux/delay.h>
#include <linux/dev_printk.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/types.h>

#include <media/media-entity.h>
#include <media/v4l2-async.h>
#include <media/v4l2-cci.h>
#include <media/v4l2-common.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-fwnode.h>
#include <media/v4l2-subdev.h>

#define T4KA3_NATIVE_WIDTH                      3280
#define T4KA3_NATIVE_HEIGHT                     2464
#define T4KA3_NATIVE_START_LEFT                 0
#define T4KA3_NATIVE_START_TOP                  0
#define T4KA3_ACTIVE_WIDTH                      3280
#define T4KA3_ACTIVE_HEIGHT                     2460
#define T4KA3_ACTIVE_START_LEFT                 0
#define T4KA3_ACTIVE_START_TOP                  2
#define T4KA3_MIN_CROP_WIDTH                    2
#define T4KA3_MIN_CROP_HEIGHT                   2

#define T4KA3_PIXELS_PER_LINE                   3440
#define T4KA3_LINES_PER_FRAME_30FPS             2492
#define T4KA3_FPS                               30
#define T4KA3_PIXEL_RATE \
        (T4KA3_PIXELS_PER_LINE * T4KA3_LINES_PER_FRAME_30FPS * T4KA3_FPS)

/*
 * TODO this really should be derived from the 19.2 MHz xvclk combined
 * with the PLL settings. But without a datasheet this is the closest
 * approximation possible.
 *
 * link-freq = pixel_rate * bpp / (lanes * 2)
 * (lanes * 2) because CSI lanes use double-data-rate (DDR) signalling.
 * bpp = 10 and lanes = 4
 */
#define T4KA3_LINK_FREQ                         ((u64)T4KA3_PIXEL_RATE * 10 / 8)

/* For enum_frame_size() full-size + binned-/quarter-size */
#define T4KA3_FRAME_SIZES                       2

#define T4KA3_REG_PRODUCT_ID_HIGH               CCI_REG8(0x0000)
#define T4KA3_REG_PRODUCT_ID_LOW                CCI_REG8(0x0001)
#define T4KA3_PRODUCT_ID                        0x1490

#define T4KA3_REG_STREAM                        CCI_REG8(0x0100)
#define T4KA3_REG_IMG_ORIENTATION               CCI_REG8(0x0101)
#define T4KA3_HFLIP_BIT                         BIT(0)
#define T4KA3_VFLIP_BIT                         BIT(1)
#define T4KA3_REG_PARAM_HOLD                    CCI_REG8(0x0104)
#define T4KA3_REG_COARSE_INTEGRATION_TIME       CCI_REG16(0x0202)
#define T4KA3_COARSE_INTEGRATION_TIME_MARGIN    6
#define T4KA3_REG_DIGGAIN_GREEN_R               CCI_REG16(0x020e)
#define T4KA3_REG_DIGGAIN_RED                   CCI_REG16(0x0210)
#define T4KA3_REG_DIGGAIN_BLUE                  CCI_REG16(0x0212)
#define T4KA3_REG_DIGGAIN_GREEN_B               CCI_REG16(0x0214)
#define T4KA3_REG_GLOBAL_GAIN                   CCI_REG16(0x0234)
#define T4KA3_MIN_GLOBAL_GAIN_SUPPORTED         0x0080
#define T4KA3_MAX_GLOBAL_GAIN_SUPPORTED         0x07ff
#define T4KA3_REG_FRAME_LENGTH_LINES            CCI_REG16(0x0340) /* aka VTS */
/* FIXME: need a datasheet to verify the min + max vblank values */
#define T4KA3_MIN_VBLANK                        4
#define T4KA3_MAX_VBLANK                        0xffff
#define T4KA3_REG_PIXELS_PER_LINE               CCI_REG16(0x0342) /* aka HTS */
/* These 2 being horz/vert start is a guess (no datasheet), always 0 */
#define T4KA3_REG_HORZ_START                    CCI_REG16(0x0344)
#define T4KA3_REG_VERT_START                    CCI_REG16(0x0346)
/* Always 3279 (T4KA3_NATIVE_WIDTH - 1, window is used to crop */
#define T4KA3_REG_HORZ_END                      CCI_REG16(0x0348)
/* Always 2463 (T4KA3_NATIVE_HEIGHT - 1, window is used to crop */
#define T4KA3_REG_VERT_END                      CCI_REG16(0x034a)
/* Output size (after cropping/window) */
#define T4KA3_REG_HORZ_OUTPUT_SIZE              CCI_REG16(0x034c)
#define T4KA3_REG_VERT_OUTPUT_SIZE              CCI_REG16(0x034e)
/* Window/crop start + size *after* binning */
#define T4KA3_REG_WIN_START_X                   CCI_REG16(0x0408)
#define T4KA3_REG_WIN_START_Y                   CCI_REG16(0x040a)
#define T4KA3_REG_WIN_WIDTH                     CCI_REG16(0x040c)
#define T4KA3_REG_WIN_HEIGHT                    CCI_REG16(0x040e)
#define T4KA3_REG_TEST_PATTERN_MODE             CCI_REG8(0x0601)
/* Unknown register at address 0x0900 */
#define T4KA3_REG_0900                          CCI_REG8(0x0900)
#define T4KA3_REG_BINNING                       CCI_REG8(0x0901)
#define T4KA3_BINNING_VAL(_bin) \
({ \
        typeof(_bin) (b) = (_bin); \
        ((b) << 4) | (b); \
})

#define to_t4ka3_sensor(_sd) container_of_const(_sd, \
                                                struct t4ka3_data, sd)
#define ctrl_to_t4ka3(_ctrl) container_of_const((_ctrl)->handler, \
                                                struct t4ka3_data, \
                                                ctrls.handler)

struct t4ka3_ctrls {
        struct v4l2_ctrl_handler handler;
        struct v4l2_ctrl *hflip;
        struct v4l2_ctrl *vflip;
        struct v4l2_ctrl *vblank;
        struct v4l2_ctrl *hblank;
        struct v4l2_ctrl *exposure;
        struct v4l2_ctrl *gain;
        struct v4l2_ctrl *test_pattern;
        struct v4l2_ctrl *link_freq;
        struct v4l2_ctrl *pixel_rate;
};

struct t4ka3_mode {
        int binning;
        u16 win_x;
        u16 win_y;
};

struct t4ka3_data {
        struct v4l2_subdev sd;
        struct media_pad pad;
        struct mutex lock; /* serialize sensor's ioctl */
        struct t4ka3_ctrls ctrls;
        struct t4ka3_mode mode;
        struct device *dev;
        struct regmap *regmap;
        struct gpio_desc *powerdown_gpio;
        struct gpio_desc *reset_gpio;
        int streaming;

        /* MIPI lane info */
        u32 link_freq_index;
        u8 mipi_lanes;
};

/* init settings */
static const struct cci_reg_sequence t4ka3_init_config[] = {
        { CCI_REG8(0x4136), 0x13 },
        { CCI_REG8(0x4137), 0x33 },
        { CCI_REG8(0x3094), 0x01 },
        { CCI_REG8(0x0233), 0x01 },
        { CCI_REG8(0x4B06), 0x01 },
        { CCI_REG8(0x4B07), 0x01 },
        { CCI_REG8(0x3028), 0x01 },
        { CCI_REG8(0x3032), 0x14 },
        { CCI_REG8(0x305C), 0x0C },
        { CCI_REG8(0x306D), 0x0A },
        { CCI_REG8(0x3071), 0xFA },
        { CCI_REG8(0x307E), 0x0A },
        { CCI_REG8(0x307F), 0xFC },
        { CCI_REG8(0x3091), 0x04 },
        { CCI_REG8(0x3092), 0x60 },
        { CCI_REG8(0x3096), 0xC0 },
        { CCI_REG8(0x3100), 0x07 },
        { CCI_REG8(0x3101), 0x4C },
        { CCI_REG8(0x3118), 0xCC },
        { CCI_REG8(0x3139), 0x06 },
        { CCI_REG8(0x313A), 0x06 },
        { CCI_REG8(0x313B), 0x04 },
        { CCI_REG8(0x3143), 0x02 },
        { CCI_REG8(0x314F), 0x0E },
        { CCI_REG8(0x3169), 0x99 },
        { CCI_REG8(0x316A), 0x99 },
        { CCI_REG8(0x3171), 0x05 },
        { CCI_REG8(0x31A1), 0xA7 },
        { CCI_REG8(0x31A2), 0x9C },
        { CCI_REG8(0x31A3), 0x8F },
        { CCI_REG8(0x31A4), 0x75 },
        { CCI_REG8(0x31A5), 0xEE },
        { CCI_REG8(0x31A6), 0xEA },
        { CCI_REG8(0x31A7), 0xE4 },
        { CCI_REG8(0x31A8), 0xE4 },
        { CCI_REG8(0x31DF), 0x05 },
        { CCI_REG8(0x31EC), 0x1B },
        { CCI_REG8(0x31ED), 0x1B },
        { CCI_REG8(0x31EE), 0x1B },
        { CCI_REG8(0x31F0), 0x1B },
        { CCI_REG8(0x31F1), 0x1B },
        { CCI_REG8(0x31F2), 0x1B },
        { CCI_REG8(0x3204), 0x3F },
        { CCI_REG8(0x3205), 0x03 },
        { CCI_REG8(0x3210), 0x01 },
        { CCI_REG8(0x3216), 0x68 },
        { CCI_REG8(0x3217), 0x58 },
        { CCI_REG8(0x3218), 0x58 },
        { CCI_REG8(0x321A), 0x68 },
        { CCI_REG8(0x321B), 0x60 },
        { CCI_REG8(0x3238), 0x03 },
        { CCI_REG8(0x3239), 0x03 },
        { CCI_REG8(0x323A), 0x05 },
        { CCI_REG8(0x323B), 0x06 },
        { CCI_REG8(0x3243), 0x03 },
        { CCI_REG8(0x3244), 0x08 },
        { CCI_REG8(0x3245), 0x01 },
        { CCI_REG8(0x3307), 0x19 },
        { CCI_REG8(0x3308), 0x19 },
        { CCI_REG8(0x3320), 0x01 },
        { CCI_REG8(0x3326), 0x15 },
        { CCI_REG8(0x3327), 0x0D },
        { CCI_REG8(0x3328), 0x01 },
        { CCI_REG8(0x3380), 0x01 },
        { CCI_REG8(0x339E), 0x07 },
        { CCI_REG8(0x3424), 0x00 },
        { CCI_REG8(0x343C), 0x01 },
        { CCI_REG8(0x3398), 0x04 },
        { CCI_REG8(0x343A), 0x10 },
        { CCI_REG8(0x339A), 0x22 },
        { CCI_REG8(0x33B4), 0x00 },
        { CCI_REG8(0x3393), 0x01 },
        { CCI_REG8(0x33B3), 0x6E },
        { CCI_REG8(0x3433), 0x06 },
        { CCI_REG8(0x3433), 0x00 },
        { CCI_REG8(0x33B3), 0x00 },
        { CCI_REG8(0x3393), 0x03 },
        { CCI_REG8(0x33B4), 0x03 },
        { CCI_REG8(0x343A), 0x00 },
        { CCI_REG8(0x339A), 0x00 },
        { CCI_REG8(0x3398), 0x00 }
};

static const struct cci_reg_sequence t4ka3_pre_mode_set_regs[] = {
        { CCI_REG8(0x0112), 0x0A },
        { CCI_REG8(0x0113), 0x0A },
        { CCI_REG8(0x0114), 0x03 },
        { CCI_REG8(0x4136), 0x13 },
        { CCI_REG8(0x4137), 0x33 },
        { CCI_REG8(0x0820), 0x0A },
        { CCI_REG8(0x0821), 0x0D },
        { CCI_REG8(0x0822), 0x00 },
        { CCI_REG8(0x0823), 0x00 },
        { CCI_REG8(0x0301), 0x0A },
        { CCI_REG8(0x0303), 0x01 },
        { CCI_REG8(0x0305), 0x04 },
        { CCI_REG8(0x0306), 0x02 },
        { CCI_REG8(0x0307), 0x18 },
        { CCI_REG8(0x030B), 0x01 },
};

static const struct cci_reg_sequence t4ka3_post_mode_set_regs[] = {
        { CCI_REG8(0x0902), 0x00 },
        { CCI_REG8(0x4220), 0x00 },
        { CCI_REG8(0x4222), 0x01 },
        { CCI_REG8(0x3380), 0x01 },
        { CCI_REG8(0x3090), 0x88 },
        { CCI_REG8(0x3394), 0x20 },
        { CCI_REG8(0x3090), 0x08 },
        { CCI_REG8(0x3394), 0x10 }
};

static const s64 link_freq_menu_items[] = {
        T4KA3_LINK_FREQ,
};

/* T4KA3 default GRBG */
static const int t4ka3_hv_flip_bayer_order[] = {
        MEDIA_BUS_FMT_SGRBG10_1X10,
        MEDIA_BUS_FMT_SBGGR10_1X10,
        MEDIA_BUS_FMT_SRGGB10_1X10,
        MEDIA_BUS_FMT_SGBRG10_1X10,
};

static const struct v4l2_rect t4ka3_default_crop = {
        .left = T4KA3_ACTIVE_START_LEFT,
        .top = T4KA3_ACTIVE_START_TOP,
        .width = T4KA3_ACTIVE_WIDTH,
        .height = T4KA3_ACTIVE_HEIGHT,
};

static void t4ka3_set_bayer_order(struct t4ka3_data *sensor,
                                  struct v4l2_mbus_framefmt *fmt)
{
        unsigned int hv_flip = 0;

        if (sensor->ctrls.vflip && sensor->ctrls.vflip->val)
                hv_flip += 1;

        if (sensor->ctrls.hflip && sensor->ctrls.hflip->val)
                hv_flip += 2;

        fmt->code = t4ka3_hv_flip_bayer_order[hv_flip];
}

static int t4ka3_update_exposure_range(struct t4ka3_data *sensor,
                                       struct v4l2_mbus_framefmt *fmt)
{
        int exp_max = fmt->height + sensor->ctrls.vblank->val -
                      T4KA3_COARSE_INTEGRATION_TIME_MARGIN;

        return __v4l2_ctrl_modify_range(sensor->ctrls.exposure, 0, exp_max,
                                        1, exp_max);
}

static void t4ka3_fill_format(struct t4ka3_data *sensor,
                              struct v4l2_mbus_framefmt *fmt,
                              unsigned int width, unsigned int height)
{
        memset(fmt, 0, sizeof(*fmt));
        fmt->width = width;
        fmt->height = height;
        fmt->field = V4L2_FIELD_NONE;
        fmt->colorspace = V4L2_COLORSPACE_RAW;
        t4ka3_set_bayer_order(sensor, fmt);
}

static void t4ka3_calc_mode(struct t4ka3_data *sensor,
                            struct v4l2_mbus_framefmt *fmt,
                            struct v4l2_rect *crop)
{
        int width;
        int height;
        int binning;

        width = fmt->width;
        height = fmt->height;

        if (width <= (crop->width / 2) && height <= (crop->height / 2))
                binning = 2;
        else
                binning = 1;

        width *= binning;
        height *= binning;

        sensor->mode.binning = binning;
        sensor->mode.win_x = (crop->left + (crop->width - width) / 2) & ~1;
        sensor->mode.win_y = (crop->top + (crop->height - height) / 2) & ~1;
        /*
         * t4ka3's window is done after binning, but must still be a
         * multiple of 2 ?
         * Round up to avoid top 2 black lines in 1640x1230 (quarter res) case.
         */
        sensor->mode.win_x = DIV_ROUND_UP(sensor->mode.win_x, binning);
        sensor->mode.win_y = DIV_ROUND_UP(sensor->mode.win_y, binning);
}

static void t4ka3_get_vblank_limits(struct t4ka3_data *sensor,
                                    struct v4l2_subdev_state *state,
                                    int *min, int *max, int *def)
{
        struct v4l2_mbus_framefmt *fmt = v4l2_subdev_state_get_format(state, 0);

        *min = T4KA3_MIN_VBLANK + (sensor->mode.binning - 1) * fmt->height;
        *max = T4KA3_MAX_VBLANK - fmt->height;
        *def = T4KA3_LINES_PER_FRAME_30FPS - fmt->height;
}

static int t4ka3_set_pad_format(struct v4l2_subdev *sd,
                                struct v4l2_subdev_state *sd_state,
                                struct v4l2_subdev_format *format)
{
        struct t4ka3_data *sensor = to_t4ka3_sensor(sd);
        struct v4l2_mbus_framefmt *fmt = &format->format;
        struct v4l2_rect *crop =
                v4l2_subdev_state_get_crop(sd_state, format->pad);
        unsigned int width, height;
        int min, max, def, ret = 0;

        /* Limit set_fmt max size to crop width / height */
        width = clamp_val(ALIGN(format->format.width, 2),
                          T4KA3_MIN_CROP_WIDTH, crop->width);
        height = clamp_val(ALIGN(format->format.height, 2),
                           T4KA3_MIN_CROP_HEIGHT, crop->height);
        t4ka3_fill_format(sensor, &format->format, width, height);

        if (format->which == V4L2_SUBDEV_FORMAT_ACTIVE && sensor->streaming)
                return -EBUSY;

        *v4l2_subdev_state_get_format(sd_state, 0) = format->format;

        if (format->which == V4L2_SUBDEV_FORMAT_TRY)
                return 0;

        t4ka3_calc_mode(sensor, fmt, crop);

        /* vblank range is height dependent adjust and reset to default */
        t4ka3_get_vblank_limits(sensor, sd_state, &min, &max, &def);
        ret = __v4l2_ctrl_modify_range(sensor->ctrls.vblank, min, max, 1, def);
        if (ret)
                return ret;

        ret = __v4l2_ctrl_s_ctrl(sensor->ctrls.vblank, def);
        if (ret)
                return ret;

        def = T4KA3_PIXELS_PER_LINE - fmt->width;
        ret = __v4l2_ctrl_modify_range(sensor->ctrls.hblank, def, def, 1, def);
        if (ret)
                return ret;

        return  __v4l2_ctrl_s_ctrl(sensor->ctrls.hblank, def);
}

/* Horizontal or vertically flip the image */
static int t4ka3_update_flip(struct v4l2_subdev *sd,
                             struct v4l2_mbus_framefmt *fmt,
                             int value, u8 flip_bit)
{
        struct t4ka3_data *sensor = to_t4ka3_sensor(sd);
        int ret;
        u64 val;

        if (sensor->streaming)
                return -EBUSY;

        val = value ? flip_bit : 0;

        ret = cci_update_bits(sensor->regmap, T4KA3_REG_IMG_ORIENTATION,
                              flip_bit, val, NULL);
        if (ret)
                return ret;

        t4ka3_set_bayer_order(sensor, fmt);

        return 0;
}

static int t4ka3_test_pattern(struct t4ka3_data *sensor, s32 value)
{
        return cci_write(sensor->regmap, T4KA3_REG_TEST_PATTERN_MODE,
                         value, NULL);
}

static int t4ka3_detect(struct t4ka3_data *sensor, u16 *id)
{
        struct i2c_client *client = v4l2_get_subdevdata(&sensor->sd);
        struct i2c_adapter *adapter = client->adapter;
        u64 high, low;
        int ret = 0;

        /* i2c check */
        if (!i2c_check_functionality(adapter, I2C_FUNC_I2C))
                return -ENODEV;

        /* check sensor chip ID  */
        cci_read(sensor->regmap, T4KA3_REG_PRODUCT_ID_HIGH, &high, &ret);
        cci_read(sensor->regmap, T4KA3_REG_PRODUCT_ID_LOW, &low, &ret);
        if (ret)
                return ret;

        *id = (((u8)high) << 8) | (u8)low;
        if (*id != T4KA3_PRODUCT_ID) {
                dev_err(sensor->dev, "main sensor t4ka3 ID error\n");
                return -ENODEV;
        }

        return 0;
}

static int t4ka3_s_ctrl(struct v4l2_ctrl *ctrl)
{
        struct t4ka3_data *sensor = ctrl_to_t4ka3(ctrl);
        struct v4l2_subdev_state *state =
                        v4l2_subdev_get_locked_active_state(&sensor->sd);
        struct v4l2_mbus_framefmt *fmt =
                        v4l2_subdev_state_get_format(state, 0);
        int ret;

        /* Update exposure range on vblank changes */
        if (ctrl->id == V4L2_CID_VBLANK) {
                ret = t4ka3_update_exposure_range(sensor, fmt);
                if (ret)
                        return ret;
        }

        /* Only apply changes to the controls if the device is powered up */
        if (!pm_runtime_get_if_in_use(sensor->sd.dev))
                return 0;

        switch (ctrl->id) {
        case V4L2_CID_TEST_PATTERN:
                ret = t4ka3_test_pattern(sensor, ctrl->val);
                break;
        case V4L2_CID_VFLIP:
                ret = t4ka3_update_flip(&sensor->sd, fmt,
                                        ctrl->val, T4KA3_VFLIP_BIT);
                break;
        case V4L2_CID_HFLIP:
                ret = t4ka3_update_flip(&sensor->sd, fmt,
                                        ctrl->val, T4KA3_HFLIP_BIT);
                break;
        case V4L2_CID_VBLANK:
                ret = cci_write(sensor->regmap, T4KA3_REG_FRAME_LENGTH_LINES,
                                fmt->height + ctrl->val, NULL);
                break;
        case V4L2_CID_EXPOSURE:
                ret = cci_write(sensor->regmap,
                                T4KA3_REG_COARSE_INTEGRATION_TIME,
                                ctrl->val, NULL);
                break;
        case V4L2_CID_ANALOGUE_GAIN:
                ret = cci_write(sensor->regmap, T4KA3_REG_GLOBAL_GAIN,
                                ctrl->val, NULL);
                break;
        default:
                ret = -EINVAL;
                break;
        }

        pm_runtime_put(sensor->sd.dev);

        return ret;
}

static int t4ka3_set_mode(struct t4ka3_data *sensor,
                          struct v4l2_subdev_state *state)
{
        struct v4l2_mbus_framefmt *fmt = v4l2_subdev_state_get_format(state, 0);
        int ret = 0;

        cci_write(sensor->regmap, T4KA3_REG_HORZ_OUTPUT_SIZE, fmt->width, &ret);
        /* Write mode-height - 2 otherwise things don't work, hw-bug ? */
        cci_write(sensor->regmap, T4KA3_REG_VERT_OUTPUT_SIZE,
                  fmt->height - 2, &ret);

        cci_write(sensor->regmap, T4KA3_REG_PIXELS_PER_LINE,
                  T4KA3_PIXELS_PER_LINE, &ret);
        /* Always use the full sensor, using window to crop */
        cci_write(sensor->regmap, T4KA3_REG_HORZ_START, 0, &ret);
        cci_write(sensor->regmap, T4KA3_REG_VERT_START, 0, &ret);
        cci_write(sensor->regmap, T4KA3_REG_HORZ_END,
                  T4KA3_NATIVE_WIDTH - 1, &ret);
        cci_write(sensor->regmap, T4KA3_REG_VERT_END,
                  T4KA3_NATIVE_HEIGHT - 1, &ret);
        /* Set window */
        cci_write(sensor->regmap, T4KA3_REG_WIN_START_X,
                  sensor->mode.win_x, &ret);
        cci_write(sensor->regmap, T4KA3_REG_WIN_START_Y,
                  sensor->mode.win_y, &ret);
        cci_write(sensor->regmap, T4KA3_REG_WIN_WIDTH, fmt->width, &ret);
        cci_write(sensor->regmap, T4KA3_REG_WIN_HEIGHT, fmt->height, &ret);
        /* Write 1 to unknown register 0x0900 */
        cci_write(sensor->regmap, T4KA3_REG_0900, 1, &ret);
        cci_write(sensor->regmap, T4KA3_REG_BINNING,
                  T4KA3_BINNING_VAL(sensor->mode.binning), &ret);

        return ret;
}

static int t4ka3_enable_stream(struct v4l2_subdev *sd,
                               struct v4l2_subdev_state *state,
                               u32 pad, u64 streams_mask)
{
        struct t4ka3_data *sensor = to_t4ka3_sensor(sd);
        int ret;

        ret = pm_runtime_get_sync(sensor->sd.dev);
        if (ret < 0) {
                dev_err(sensor->dev, "power-up err.\n");
                goto error_powerdown;
        }

        cci_multi_reg_write(sensor->regmap, t4ka3_init_config,
                            ARRAY_SIZE(t4ka3_init_config), &ret);
        /* enable group hold */
        cci_write(sensor->regmap, T4KA3_REG_PARAM_HOLD, 1, &ret);
        cci_multi_reg_write(sensor->regmap, t4ka3_pre_mode_set_regs,
                            ARRAY_SIZE(t4ka3_pre_mode_set_regs), &ret);
        if (ret)
                goto error_powerdown;

        ret = t4ka3_set_mode(sensor, state);
        if (ret)
                goto error_powerdown;

        ret = cci_multi_reg_write(sensor->regmap, t4ka3_post_mode_set_regs,
                                  ARRAY_SIZE(t4ka3_post_mode_set_regs), NULL);
        if (ret)
                goto error_powerdown;

        /* Restore value of all ctrls */
        ret = __v4l2_ctrl_handler_setup(&sensor->ctrls.handler);
        if (ret)
                goto error_powerdown;

        /* disable group hold */
        cci_write(sensor->regmap, T4KA3_REG_PARAM_HOLD, 0, &ret);
        cci_write(sensor->regmap, T4KA3_REG_STREAM, 1, &ret);
        if (ret)
                goto error_powerdown;

        sensor->streaming = 1;

        return ret;

error_powerdown:
        pm_runtime_put(sensor->sd.dev);

        return ret;
}

static int t4ka3_disable_stream(struct v4l2_subdev *sd,
                                struct v4l2_subdev_state *state,
                                u32 pad, u64 streams_mask)
{
        struct t4ka3_data *sensor = to_t4ka3_sensor(sd);
        int ret;

        ret = cci_write(sensor->regmap, T4KA3_REG_STREAM, 0, NULL);
        pm_runtime_put(sensor->sd.dev);
        sensor->streaming = 0;

        if (ret)
                dev_err(sensor->dev,
                        "failed to disable stream with return value: %d\n",
                        ret);

        return 0;
}

static int t4ka3_get_selection(struct v4l2_subdev *sd,
                               struct v4l2_subdev_state *state,
                               struct v4l2_subdev_selection *sel)
{
        switch (sel->target) {
        case V4L2_SEL_TGT_CROP:
                sel->r = *v4l2_subdev_state_get_crop(state, sel->pad);
                break;
        case V4L2_SEL_TGT_NATIVE_SIZE:
        case V4L2_SEL_TGT_CROP_BOUNDS:
                sel->r.top = 0;
                sel->r.left = 0;
                sel->r.width = T4KA3_NATIVE_WIDTH;
                sel->r.height = T4KA3_NATIVE_HEIGHT;
                break;
        case V4L2_SEL_TGT_CROP_DEFAULT:
                sel->r = t4ka3_default_crop;
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static int t4ka3_set_selection(struct v4l2_subdev *sd,
                               struct v4l2_subdev_state *state,
                               struct v4l2_subdev_selection *sel)
{
        struct t4ka3_data *sensor = to_t4ka3_sensor(sd);
        struct v4l2_mbus_framefmt *format;
        struct v4l2_rect *crop;
        struct v4l2_rect rect;

        if (sel->target != V4L2_SEL_TGT_CROP)
                return -EINVAL;

        /*
         * Clamp the boundaries of the crop rectangle to the size of the sensor
         * pixel array. Align to multiples of 2 to ensure Bayer pattern isn't
         * disrupted.
         */
        rect.left = clamp_val(ALIGN(sel->r.left, 2),
                              T4KA3_NATIVE_START_LEFT, T4KA3_NATIVE_WIDTH);
        rect.top = clamp_val(ALIGN(sel->r.top, 2),
                             T4KA3_NATIVE_START_TOP, T4KA3_NATIVE_HEIGHT);
        rect.width = clamp_val(ALIGN(sel->r.width, 2), T4KA3_MIN_CROP_WIDTH,
                               T4KA3_NATIVE_WIDTH - rect.left);
        rect.height = clamp_val(ALIGN(sel->r.height, 2), T4KA3_MIN_CROP_HEIGHT,
                                T4KA3_NATIVE_HEIGHT - rect.top);

        crop = v4l2_subdev_state_get_crop(state, sel->pad);

        if (rect.width != crop->width || rect.height != crop->height) {
                /*
                 * Reset the output image size if the crop rectangle size has
                 * been modified.
                 */
                format = v4l2_subdev_state_get_format(state, sel->pad);
                format->width = rect.width;
                format->height = rect.height;
                if (sel->which == V4L2_SUBDEV_FORMAT_ACTIVE)
                        t4ka3_calc_mode(sensor, format, crop);
        }

        sel->r = *crop = rect;

        return 0;
}

static int
t4ka3_enum_mbus_code(struct v4l2_subdev *sd,
                     struct v4l2_subdev_state *sd_state,
                     struct v4l2_subdev_mbus_code_enum *code)
{
        if (code->index)
                return -EINVAL;

        code->code = MEDIA_BUS_FMT_SGRBG10_1X10;

        return 0;
}

static int t4ka3_enum_frame_size(struct v4l2_subdev *sd,
                                 struct v4l2_subdev_state *sd_state,
                                 struct v4l2_subdev_frame_size_enum *fse)
{
        struct v4l2_rect *crop;

        if (fse->index >= T4KA3_FRAME_SIZES)
                return -EINVAL;

        crop = v4l2_subdev_state_get_crop(sd_state, fse->pad);

        fse->min_width = crop->width / (fse->index + 1);
        fse->min_height = crop->height / (fse->index + 1);
        fse->max_width = fse->min_width;
        fse->max_height = fse->min_height;

        return 0;
}

static int t4ka3_check_hwcfg(struct t4ka3_data *sensor)
{
        struct fwnode_handle *fwnode = dev_fwnode(sensor->dev);
        struct v4l2_fwnode_endpoint bus_cfg = {
                .bus_type = V4L2_MBUS_CSI2_DPHY,
        };
        struct fwnode_handle *endpoint;
        unsigned long link_freq_bitmap;
        int ret;

        endpoint = fwnode_graph_get_next_endpoint(fwnode, NULL);

        ret = v4l2_fwnode_endpoint_alloc_parse(endpoint, &bus_cfg);
        fwnode_handle_put(endpoint);
        if (ret)
                return ret;

        ret = v4l2_link_freq_to_bitmap(sensor->dev, bus_cfg.link_frequencies,
                                       bus_cfg.nr_of_link_frequencies,
                                       link_freq_menu_items,
                                       ARRAY_SIZE(link_freq_menu_items),
                                       &link_freq_bitmap);

        if (ret < 0)
                goto out_free_bus_cfg;

        sensor->link_freq_index = ffs(link_freq_bitmap) - 1;

        /* 4 MIPI lanes */
        if (bus_cfg.bus.mipi_csi2.num_data_lanes != 4) {
                ret = dev_err_probe(sensor->dev, -EINVAL,
                                    "number of CSI2 data lanes %u is not supported\n",
                                    bus_cfg.bus.mipi_csi2.num_data_lanes);
                goto out_free_bus_cfg;
        }

        sensor->mipi_lanes = bus_cfg.bus.mipi_csi2.num_data_lanes;

out_free_bus_cfg:
        v4l2_fwnode_endpoint_free(&bus_cfg);

        return ret;
}

static int t4ka3_init_state(struct v4l2_subdev *sd,
                            struct v4l2_subdev_state *sd_state)
{
        struct t4ka3_data *sensor = to_t4ka3_sensor(sd);

        *v4l2_subdev_state_get_crop(sd_state, 0) = t4ka3_default_crop;

        t4ka3_fill_format(sensor, v4l2_subdev_state_get_format(sd_state, 0),
                          T4KA3_ACTIVE_WIDTH, T4KA3_ACTIVE_HEIGHT);
        return 0;
}

static const struct v4l2_ctrl_ops t4ka3_ctrl_ops = {
        .s_ctrl = t4ka3_s_ctrl,
};

static const struct v4l2_subdev_video_ops t4ka3_video_ops = {
        .s_stream = v4l2_subdev_s_stream_helper,
};

static const struct v4l2_subdev_pad_ops t4ka3_pad_ops = {
        .enum_mbus_code = t4ka3_enum_mbus_code,
        .enum_frame_size = t4ka3_enum_frame_size,
        .get_fmt = v4l2_subdev_get_fmt,
        .set_fmt = t4ka3_set_pad_format,
        .get_selection = t4ka3_get_selection,
        .set_selection = t4ka3_set_selection,
        .enable_streams = t4ka3_enable_stream,
        .disable_streams = t4ka3_disable_stream,
};

static const struct v4l2_subdev_ops t4ka3_ops = {
        .video = &t4ka3_video_ops,
        .pad = &t4ka3_pad_ops,
};

static const struct v4l2_subdev_internal_ops t4ka3_internal_ops = {
        .init_state = t4ka3_init_state,
};

static int t4ka3_init_controls(struct t4ka3_data *sensor)
{
        const struct v4l2_ctrl_ops *ops = &t4ka3_ctrl_ops;
        struct t4ka3_ctrls *ctrls = &sensor->ctrls;
        struct v4l2_subdev_state *state;
        struct v4l2_mbus_framefmt *fmt;
        struct v4l2_rect *crop;
        struct v4l2_ctrl_handler *hdl = &ctrls->handler;
        struct v4l2_fwnode_device_properties props;
        int ret, min, max, def;
        static const char * const test_pattern_menu[] = {
                "Disabled",
                "Solid White",
                "Color Bars",
                "Gradient",
                "Random Data",
        };

        v4l2_ctrl_handler_init(hdl, 11);

        hdl->lock = &sensor->lock;

        ctrls->vflip = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_VFLIP, 0, 1, 1, 0);
        ctrls->hflip = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_HFLIP, 0, 1, 1, 0);

        ctrls->test_pattern =
                v4l2_ctrl_new_std_menu_items(hdl, ops,
                                             V4L2_CID_TEST_PATTERN,
                                             ARRAY_SIZE(test_pattern_menu) - 1,
                                             0, 0, test_pattern_menu);
        ctrls->link_freq = v4l2_ctrl_new_int_menu(hdl, NULL,
                                                  V4L2_CID_LINK_FREQ,
                                                  0, 0, link_freq_menu_items);
        ctrls->pixel_rate = v4l2_ctrl_new_std(hdl, NULL, V4L2_CID_PIXEL_RATE,
                                              0, T4KA3_PIXEL_RATE,
                                              1, T4KA3_PIXEL_RATE);

        state = v4l2_subdev_lock_and_get_active_state(&sensor->sd);
        fmt = v4l2_subdev_state_get_format(state, 0);
        crop = v4l2_subdev_state_get_crop(state, 0);

        t4ka3_calc_mode(sensor, fmt, crop);
        t4ka3_get_vblank_limits(sensor, state, &min, &max, &def);

        v4l2_subdev_unlock_state(state);

        ctrls->vblank = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_VBLANK,
                                          min, max, 1, def);

        def = T4KA3_PIXELS_PER_LINE - T4KA3_ACTIVE_WIDTH;
        ctrls->hblank = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_HBLANK,
                                          def, def, 1, def);

        max = T4KA3_LINES_PER_FRAME_30FPS -
              T4KA3_COARSE_INTEGRATION_TIME_MARGIN;
        ctrls->exposure = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_EXPOSURE,
                                            0, max, 1, max);

        ctrls->gain = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_ANALOGUE_GAIN,
                                        T4KA3_MIN_GLOBAL_GAIN_SUPPORTED,
                                        T4KA3_MAX_GLOBAL_GAIN_SUPPORTED,
                                        1, T4KA3_MIN_GLOBAL_GAIN_SUPPORTED);

        ret = v4l2_fwnode_device_parse(sensor->dev, &props);
        if (ret)
                return ret;

        v4l2_ctrl_new_fwnode_properties(hdl, ops, &props);

        if (hdl->error)
                return hdl->error;

        ctrls->vflip->flags |= V4L2_CTRL_FLAG_MODIFY_LAYOUT;
        ctrls->hflip->flags |= V4L2_CTRL_FLAG_MODIFY_LAYOUT;
        ctrls->link_freq->flags |= V4L2_CTRL_FLAG_READ_ONLY;
        ctrls->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;

        sensor->sd.ctrl_handler = hdl;

        return 0;
}

static int t4ka3_pm_suspend(struct device *dev)
{
        struct t4ka3_data *sensor = dev_get_drvdata(dev);

        gpiod_set_value_cansleep(sensor->powerdown_gpio, 1);
        gpiod_set_value_cansleep(sensor->reset_gpio, 1);

        return 0;
}

static int t4ka3_pm_resume(struct device *dev)
{
        struct t4ka3_data *sensor = dev_get_drvdata(dev);
        u16 sensor_id;
        int ret;

        usleep_range(5000, 6000);

        gpiod_set_value_cansleep(sensor->powerdown_gpio, 0);
        gpiod_set_value_cansleep(sensor->reset_gpio, 0);

        /* waiting for the sensor after powering up */
        fsleep(20000);

        ret = t4ka3_detect(sensor, &sensor_id);
        if (ret) {
                dev_err(sensor->dev, "sensor detect failed\n");
                gpiod_set_value_cansleep(sensor->powerdown_gpio, 1);
                gpiod_set_value_cansleep(sensor->reset_gpio, 1);

                return ret;
        }

        return 0;
}

static DEFINE_RUNTIME_DEV_PM_OPS(t4ka3_pm_ops, t4ka3_pm_suspend,
                                 t4ka3_pm_resume, NULL);

static void t4ka3_remove(struct i2c_client *client)
{
        struct v4l2_subdev *sd = i2c_get_clientdata(client);
        struct t4ka3_data *sensor = to_t4ka3_sensor(sd);

        v4l2_async_unregister_subdev(&sensor->sd);
        v4l2_ctrl_handler_free(&sensor->ctrls.handler);
        v4l2_subdev_cleanup(sd);
        media_entity_cleanup(&sensor->sd.entity);

        /*
         * Disable runtime PM. In case runtime PM is disabled in the kernel,
         * make sure to turn power off manually.
         */
        pm_runtime_disable(&client->dev);
        if (!pm_runtime_status_suspended(&client->dev))
                t4ka3_pm_suspend(&client->dev);
        pm_runtime_set_suspended(&client->dev);
}

static int t4ka3_probe(struct i2c_client *client)
{
        struct t4ka3_data *sensor;
        int ret;

        /* allocate sensor device & init sub device */
        sensor = devm_kzalloc(&client->dev, sizeof(*sensor), GFP_KERNEL);
        if (!sensor)
                return -ENOMEM;

        sensor->dev = &client->dev;

        ret = t4ka3_check_hwcfg(sensor);
        if (ret)
                return ret;

        mutex_init(&sensor->lock);

        v4l2_i2c_subdev_init(&sensor->sd, client, &t4ka3_ops);
        sensor->sd.internal_ops = &t4ka3_internal_ops;

        sensor->powerdown_gpio = devm_gpiod_get(&client->dev, "powerdown",
                                                GPIOD_OUT_HIGH);
        if (IS_ERR(sensor->powerdown_gpio))
                return dev_err_probe(&client->dev,
                                     PTR_ERR(sensor->powerdown_gpio),
                                     "getting powerdown GPIO\n");

        sensor->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
                                                     GPIOD_OUT_HIGH);
        if (IS_ERR(sensor->reset_gpio))
                return dev_err_probe(&client->dev, PTR_ERR(sensor->reset_gpio),
                                     "getting reset GPIO\n");

        sensor->regmap = devm_cci_regmap_init_i2c(client, 16);
        if (IS_ERR(sensor->regmap))
                return PTR_ERR(sensor->regmap);

        ret = t4ka3_pm_resume(sensor->dev);
        if (ret)
                return ret;

        pm_runtime_set_active(&client->dev);
        pm_runtime_enable(&client->dev);

        sensor->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
        sensor->pad.flags = MEDIA_PAD_FL_SOURCE;
        sensor->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;

        ret = media_entity_pads_init(&sensor->sd.entity, 1, &sensor->pad);
        if (ret)
                goto err_pm_disable;

        sensor->sd.state_lock = sensor->ctrls.handler.lock;
        ret = v4l2_subdev_init_finalize(&sensor->sd);
        if (ret < 0) {
                dev_err(&client->dev, "failed to init subdev: %d", ret);
                goto err_media_entity;
        }

        ret = t4ka3_init_controls(sensor);
        if (ret)
                goto err_controls;

        ret = v4l2_async_register_subdev_sensor(&sensor->sd);
        if (ret)
                goto err_controls;

        pm_runtime_set_autosuspend_delay(&client->dev, 1000);
        pm_runtime_idle(&client->dev);

        return 0;

err_controls:
        v4l2_ctrl_handler_free(&sensor->ctrls.handler);
        v4l2_subdev_cleanup(&sensor->sd);

err_media_entity:
        media_entity_cleanup(&sensor->sd.entity);

err_pm_disable:
        pm_runtime_disable(&client->dev);
        pm_runtime_put_noidle(&client->dev);
        t4ka3_pm_suspend(&client->dev);

        return ret;
}

static const struct acpi_device_id t4ka3_acpi_match[] = {
        { "XMCC0003" },
        {}
};
MODULE_DEVICE_TABLE(acpi, t4ka3_acpi_match);

static struct i2c_driver t4ka3_driver = {
        .driver = {
                .name = "t4ka3",
                .acpi_match_table = ACPI_PTR(t4ka3_acpi_match),
                .pm = pm_sleep_ptr(&t4ka3_pm_ops),
        },
        .probe = t4ka3_probe,
        .remove = t4ka3_remove,
};
module_i2c_driver(t4ka3_driver)

MODULE_DESCRIPTION("A low-level driver for T4KA3 sensor");
MODULE_AUTHOR("HARVEY LV <harvey.lv@intel.com>");
MODULE_AUTHOR("Kate Hsuan <hpa@redhat.com>");
MODULE_LICENSE("GPL");