root/drivers/media/i2c/ov02a10.c
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2020 MediaTek Inc.

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
#include <linux/units.h>
#include <media/media-entity.h>
#include <media/v4l2-async.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-fwnode.h>
#include <media/v4l2-subdev.h>

#define OV02A10_ID                                      0x2509
#define OV02A10_ID_MASK                                 GENMASK(15, 0)

#define OV02A10_REG_CHIP_ID                             0x02

/* Bit[1] vertical upside down */
/* Bit[0] horizontal mirror */
#define REG_MIRROR_FLIP_CONTROL                         0x3f

/* Orientation */
#define REG_MIRROR_FLIP_ENABLE                          0x03

/* Bit[2:0] MIPI transmission speed select */
#define TX_SPEED_AREA_SEL                               0xa1
#define OV02A10_MIPI_TX_SPEED_DEFAULT                   0x04

#define REG_PAGE_SWITCH                                 0xfd
#define REG_GLOBAL_EFFECTIVE                            0x01
#define REG_ENABLE                                      BIT(0)

#define REG_SC_CTRL_MODE                                0xac
#define SC_CTRL_MODE_STANDBY                            0x00
#define SC_CTRL_MODE_STREAMING                          0x01

/* Exposure control */
#define OV02A10_EXP_SHIFT                               8
#define OV02A10_REG_EXPOSURE_H                          0x03
#define OV02A10_REG_EXPOSURE_L                          0x04
#define OV02A10_EXPOSURE_MIN                            4
#define OV02A10_EXPOSURE_MAX_MARGIN                     4
#define OV02A10_EXPOSURE_STEP                           1

/* Vblanking control */
#define OV02A10_VTS_SHIFT                               8
#define OV02A10_REG_VTS_H                               0x05
#define OV02A10_REG_VTS_L                               0x06
#define OV02A10_VTS_MAX                                 0x209f
#define OV02A10_BASE_LINES                              1224

/* Analog gain control */
#define OV02A10_REG_GAIN                                0x24
#define OV02A10_GAIN_MIN                                0x10
#define OV02A10_GAIN_MAX                                0xf8
#define OV02A10_GAIN_STEP                               0x01
#define OV02A10_GAIN_DEFAULT                            0x40

/* Test pattern control */
#define OV02A10_REG_TEST_PATTERN                        0xb6

#define OV02A10_LINK_FREQ_390MHZ                        (390 * HZ_PER_MHZ)
#define OV02A10_ECLK_FREQ                               (24 * HZ_PER_MHZ)

/* Number of lanes supported by this driver */
#define OV02A10_DATA_LANES                              1

/* Bits per sample of sensor output */
#define OV02A10_BITS_PER_SAMPLE                         10

static const char * const ov02a10_supply_names[] = {
        "dovdd",        /* Digital I/O power */
        "avdd",         /* Analog power */
        "dvdd",         /* Digital core power */
};

struct ov02a10_reg {
        u8 addr;
        u8 val;
};

struct ov02a10_reg_list {
        u32 num_of_regs;
        const struct ov02a10_reg *regs;
};

struct ov02a10_mode {
        u32 width;
        u32 height;
        u32 exp_def;
        u32 hts_def;
        u32 vts_def;
        const struct ov02a10_reg_list reg_list;
};

struct ov02a10 {
        struct device *dev;

        /* Indication of MIPI transmission speed select */
        u32 mipi_clock_voltage;

        struct clk *eclk;
        struct gpio_desc *pd_gpio;
        struct gpio_desc *rst_gpio;
        struct regulator_bulk_data supplies[ARRAY_SIZE(ov02a10_supply_names)];

        bool streaming;
        bool upside_down;

        /*
         * Serialize control access, get/set format, get selection
         * and start streaming.
         */
        struct mutex mutex;
        struct v4l2_subdev subdev;
        struct media_pad pad;
        struct v4l2_mbus_framefmt fmt;
        struct v4l2_ctrl_handler ctrl_handler;
        struct v4l2_ctrl *exposure;

        const struct ov02a10_mode *cur_mode;
};

static inline struct ov02a10 *to_ov02a10(struct v4l2_subdev *sd)
{
        return container_of(sd, struct ov02a10, subdev);
}

/*
 * eclk 24Mhz
 * pclk 39Mhz
 * linelength 934(0x3a6)
 * framelength 1390(0x56E)
 * grabwindow_width 1600
 * grabwindow_height 1200
 * max_framerate 30fps
 * mipi_datarate per lane 780Mbps
 */
static const struct ov02a10_reg ov02a10_1600x1200_regs[] = {
        {0xfd, 0x01},
        {0xac, 0x00},
        {0xfd, 0x00},
        {0x2f, 0x29},
        {0x34, 0x00},
        {0x35, 0x21},
        {0x30, 0x15},
        {0x33, 0x01},
        {0xfd, 0x01},
        {0x44, 0x00},
        {0x2a, 0x4c},
        {0x2b, 0x1e},
        {0x2c, 0x60},
        {0x25, 0x11},
        {0x03, 0x01},
        {0x04, 0xae},
        {0x09, 0x00},
        {0x0a, 0x02},
        {0x06, 0xa6},
        {0x31, 0x00},
        {0x24, 0x40},
        {0x01, 0x01},
        {0xfb, 0x73},
        {0xfd, 0x01},
        {0x16, 0x04},
        {0x1c, 0x09},
        {0x21, 0x42},
        {0x12, 0x04},
        {0x13, 0x10},
        {0x11, 0x40},
        {0x33, 0x81},
        {0xd0, 0x00},
        {0xd1, 0x01},
        {0xd2, 0x00},
        {0x50, 0x10},
        {0x51, 0x23},
        {0x52, 0x20},
        {0x53, 0x10},
        {0x54, 0x02},
        {0x55, 0x20},
        {0x56, 0x02},
        {0x58, 0x48},
        {0x5d, 0x15},
        {0x5e, 0x05},
        {0x66, 0x66},
        {0x68, 0x68},
        {0x6b, 0x00},
        {0x6c, 0x00},
        {0x6f, 0x40},
        {0x70, 0x40},
        {0x71, 0x0a},
        {0x72, 0xf0},
        {0x73, 0x10},
        {0x75, 0x80},
        {0x76, 0x10},
        {0x84, 0x00},
        {0x85, 0x10},
        {0x86, 0x10},
        {0x87, 0x00},
        {0x8a, 0x22},
        {0x8b, 0x22},
        {0x19, 0xf1},
        {0x29, 0x01},
        {0xfd, 0x01},
        {0x9d, 0x16},
        {0xa0, 0x29},
        {0xa1, 0x04},
        {0xad, 0x62},
        {0xae, 0x00},
        {0xaf, 0x85},
        {0xb1, 0x01},
        {0x8e, 0x06},
        {0x8f, 0x40},
        {0x90, 0x04},
        {0x91, 0xb0},
        {0x45, 0x01},
        {0x46, 0x00},
        {0x47, 0x6c},
        {0x48, 0x03},
        {0x49, 0x8b},
        {0x4a, 0x00},
        {0x4b, 0x07},
        {0x4c, 0x04},
        {0x4d, 0xb7},
        {0xf0, 0x40},
        {0xf1, 0x40},
        {0xf2, 0x40},
        {0xf3, 0x40},
        {0x3f, 0x00},
        {0xfd, 0x01},
        {0x05, 0x00},
        {0x06, 0xa6},
        {0xfd, 0x01},
};

static const char * const ov02a10_test_pattern_menu[] = {
        "Disabled",
        "Eight Vertical Colour Bars",
};

static const s64 link_freq_menu_items[] = {
        OV02A10_LINK_FREQ_390MHZ,
};

static u64 to_pixel_rate(u32 f_index)
{
        u64 pixel_rate = link_freq_menu_items[f_index] * 2 * OV02A10_DATA_LANES;

        do_div(pixel_rate, OV02A10_BITS_PER_SAMPLE);

        return pixel_rate;
}

static const struct ov02a10_mode supported_modes[] = {
        {
                .width = 1600,
                .height = 1200,
                .exp_def = 0x01ae,
                .hts_def = 0x03a6,
                .vts_def = 0x056e,
                .reg_list = {
                        .num_of_regs = ARRAY_SIZE(ov02a10_1600x1200_regs),
                        .regs = ov02a10_1600x1200_regs,
                },
        },
};

static int ov02a10_write_array(struct ov02a10 *ov02a10,
                               const struct ov02a10_reg_list *r_list)
{
        struct i2c_client *client = v4l2_get_subdevdata(&ov02a10->subdev);
        unsigned int i;
        int ret;

        for (i = 0; i < r_list->num_of_regs; i++) {
                ret = i2c_smbus_write_byte_data(client, r_list->regs[i].addr,
                                                r_list->regs[i].val);
                if (ret < 0)
                        return ret;
        }

        return 0;
}

static void ov02a10_fill_fmt(const struct ov02a10_mode *mode,
                             struct v4l2_mbus_framefmt *fmt)
{
        fmt->width = mode->width;
        fmt->height = mode->height;
        fmt->field = V4L2_FIELD_NONE;
}

static int ov02a10_set_fmt(struct v4l2_subdev *sd,
                           struct v4l2_subdev_state *sd_state,
                           struct v4l2_subdev_format *fmt)
{
        struct ov02a10 *ov02a10 = to_ov02a10(sd);
        struct v4l2_mbus_framefmt *mbus_fmt = &fmt->format;
        struct v4l2_mbus_framefmt *frame_fmt;
        int ret = 0;

        mutex_lock(&ov02a10->mutex);

        if (ov02a10->streaming && fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
                ret = -EBUSY;
                goto out_unlock;
        }

        /* Only one sensor mode supported */
        mbus_fmt->code = ov02a10->fmt.code;
        ov02a10_fill_fmt(ov02a10->cur_mode, mbus_fmt);

        if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
                frame_fmt = v4l2_subdev_state_get_format(sd_state, 0);
        else
                frame_fmt = &ov02a10->fmt;

        *frame_fmt = *mbus_fmt;

out_unlock:
        mutex_unlock(&ov02a10->mutex);
        return ret;
}

static int ov02a10_get_fmt(struct v4l2_subdev *sd,
                           struct v4l2_subdev_state *sd_state,
                           struct v4l2_subdev_format *fmt)
{
        struct ov02a10 *ov02a10 = to_ov02a10(sd);
        struct v4l2_mbus_framefmt *mbus_fmt = &fmt->format;

        mutex_lock(&ov02a10->mutex);

        if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
                fmt->format = *v4l2_subdev_state_get_format(sd_state,
                                                            fmt->pad);
        } else {
                fmt->format = ov02a10->fmt;
                mbus_fmt->code = ov02a10->fmt.code;
                ov02a10_fill_fmt(ov02a10->cur_mode, mbus_fmt);
        }

        mutex_unlock(&ov02a10->mutex);

        return 0;
}

static int ov02a10_enum_mbus_code(struct v4l2_subdev *sd,
                                  struct v4l2_subdev_state *sd_state,
                                  struct v4l2_subdev_mbus_code_enum *code)
{
        struct ov02a10 *ov02a10 = to_ov02a10(sd);

        if (code->index != 0)
                return -EINVAL;

        code->code = ov02a10->fmt.code;

        return 0;
}

static int ov02a10_enum_frame_sizes(struct v4l2_subdev *sd,
                                    struct v4l2_subdev_state *sd_state,
                                    struct v4l2_subdev_frame_size_enum *fse)
{
        if (fse->index >= ARRAY_SIZE(supported_modes))
                return -EINVAL;

        fse->min_width  = supported_modes[fse->index].width;
        fse->max_width  = supported_modes[fse->index].width;
        fse->max_height = supported_modes[fse->index].height;
        fse->min_height = supported_modes[fse->index].height;

        return 0;
}

static int ov02a10_check_sensor_id(struct ov02a10 *ov02a10)
{
        struct i2c_client *client = v4l2_get_subdevdata(&ov02a10->subdev);
        u16 chip_id;
        int ret;

        /* Validate the chip ID */
        ret = i2c_smbus_read_word_swapped(client, OV02A10_REG_CHIP_ID);
        if (ret < 0)
                return ret;

        chip_id = le16_to_cpu((__force __le16)ret);

        if ((chip_id & OV02A10_ID_MASK) != OV02A10_ID) {
                dev_err(ov02a10->dev, "unexpected sensor id(0x%04x)\n", chip_id);
                return -EINVAL;
        }

        return 0;
}

static int ov02a10_power_on(struct device *dev)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct v4l2_subdev *sd = i2c_get_clientdata(client);
        struct ov02a10 *ov02a10 = to_ov02a10(sd);
        int ret;

        gpiod_set_value_cansleep(ov02a10->rst_gpio, 1);
        gpiod_set_value_cansleep(ov02a10->pd_gpio, 1);

        ret = clk_prepare_enable(ov02a10->eclk);
        if (ret < 0) {
                dev_err(dev, "failed to enable eclk\n");
                return ret;
        }

        ret = regulator_bulk_enable(ARRAY_SIZE(ov02a10_supply_names),
                                    ov02a10->supplies);
        if (ret < 0) {
                dev_err(dev, "failed to enable regulators\n");
                goto disable_clk;
        }
        usleep_range(5000, 6000);

        gpiod_set_value_cansleep(ov02a10->pd_gpio, 0);
        usleep_range(5000, 6000);

        gpiod_set_value_cansleep(ov02a10->rst_gpio, 0);
        usleep_range(5000, 6000);

        ret = ov02a10_check_sensor_id(ov02a10);
        if (ret)
                goto disable_regulator;

        return 0;

disable_regulator:
        regulator_bulk_disable(ARRAY_SIZE(ov02a10_supply_names),
                               ov02a10->supplies);
disable_clk:
        clk_disable_unprepare(ov02a10->eclk);

        return ret;
}

static int ov02a10_power_off(struct device *dev)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct v4l2_subdev *sd = i2c_get_clientdata(client);
        struct ov02a10 *ov02a10 = to_ov02a10(sd);

        gpiod_set_value_cansleep(ov02a10->rst_gpio, 1);
        clk_disable_unprepare(ov02a10->eclk);
        gpiod_set_value_cansleep(ov02a10->pd_gpio, 1);
        regulator_bulk_disable(ARRAY_SIZE(ov02a10_supply_names),
                               ov02a10->supplies);

        return 0;
}

static int __ov02a10_start_stream(struct ov02a10 *ov02a10)
{
        struct i2c_client *client = v4l2_get_subdevdata(&ov02a10->subdev);
        const struct ov02a10_reg_list *reg_list;
        int ret;

        /* Apply default values of current mode */
        reg_list = &ov02a10->cur_mode->reg_list;
        ret = ov02a10_write_array(ov02a10, reg_list);
        if (ret)
                return ret;

        /* Apply customized values from user */
        ret = __v4l2_ctrl_handler_setup(ov02a10->subdev.ctrl_handler);
        if (ret)
                return ret;

        /* Set orientation to 180 degree */
        if (ov02a10->upside_down) {
                ret = i2c_smbus_write_byte_data(client, REG_MIRROR_FLIP_CONTROL,
                                                REG_MIRROR_FLIP_ENABLE);
                if (ret < 0) {
                        dev_err(ov02a10->dev, "failed to set orientation\n");
                        return ret;
                }
                ret = i2c_smbus_write_byte_data(client, REG_GLOBAL_EFFECTIVE,
                                                REG_ENABLE);
                if (ret < 0)
                        return ret;
        }

        /* Set MIPI TX speed according to DT property */
        if (ov02a10->mipi_clock_voltage != OV02A10_MIPI_TX_SPEED_DEFAULT) {
                ret = i2c_smbus_write_byte_data(client, TX_SPEED_AREA_SEL,
                                                ov02a10->mipi_clock_voltage);
                if (ret < 0)
                        return ret;
        }

        /* Set stream on register */
        return i2c_smbus_write_byte_data(client, REG_SC_CTRL_MODE,
                                         SC_CTRL_MODE_STREAMING);
}

static int __ov02a10_stop_stream(struct ov02a10 *ov02a10)
{
        struct i2c_client *client = v4l2_get_subdevdata(&ov02a10->subdev);

        return i2c_smbus_write_byte_data(client, REG_SC_CTRL_MODE,
                                         SC_CTRL_MODE_STANDBY);
}

static int ov02a10_init_state(struct v4l2_subdev *sd,
                              struct v4l2_subdev_state *sd_state)
{
        struct v4l2_subdev_format fmt = {
                .which = V4L2_SUBDEV_FORMAT_TRY,
                .format = {
                        .width = 1600,
                        .height = 1200,
                }
        };

        ov02a10_set_fmt(sd, sd_state, &fmt);

        return 0;
}

static int ov02a10_s_stream(struct v4l2_subdev *sd, int on)
{
        struct ov02a10 *ov02a10 = to_ov02a10(sd);
        int ret;

        mutex_lock(&ov02a10->mutex);

        if (ov02a10->streaming == on) {
                ret = 0;
                goto unlock_and_return;
        }

        if (on) {
                ret = pm_runtime_resume_and_get(ov02a10->dev);
                if (ret < 0)
                        goto unlock_and_return;

                ret = __ov02a10_start_stream(ov02a10);
                if (ret) {
                        __ov02a10_stop_stream(ov02a10);
                        ov02a10->streaming = !on;
                        goto err_rpm_put;
                }
        } else {
                __ov02a10_stop_stream(ov02a10);
                pm_runtime_put(ov02a10->dev);
        }

        ov02a10->streaming = on;
        mutex_unlock(&ov02a10->mutex);

        return 0;

err_rpm_put:
        pm_runtime_put(ov02a10->dev);
unlock_and_return:
        mutex_unlock(&ov02a10->mutex);

        return ret;
}

static const struct dev_pm_ops ov02a10_pm_ops = {
        SET_RUNTIME_PM_OPS(ov02a10_power_off, ov02a10_power_on, NULL)
};

static int ov02a10_set_exposure(struct ov02a10 *ov02a10, int val)
{
        struct i2c_client *client = v4l2_get_subdevdata(&ov02a10->subdev);
        int ret;

        ret = i2c_smbus_write_byte_data(client, REG_PAGE_SWITCH, REG_ENABLE);
        if (ret < 0)
                return ret;

        ret = i2c_smbus_write_byte_data(client, OV02A10_REG_EXPOSURE_H,
                                        val >> OV02A10_EXP_SHIFT);
        if (ret < 0)
                return ret;

        ret = i2c_smbus_write_byte_data(client, OV02A10_REG_EXPOSURE_L, val);
        if (ret < 0)
                return ret;

        return i2c_smbus_write_byte_data(client, REG_GLOBAL_EFFECTIVE,
                                         REG_ENABLE);
}

static int ov02a10_set_gain(struct ov02a10 *ov02a10, int val)
{
        struct i2c_client *client = v4l2_get_subdevdata(&ov02a10->subdev);
        int ret;

        ret = i2c_smbus_write_byte_data(client, REG_PAGE_SWITCH, REG_ENABLE);
        if (ret < 0)
                return ret;

        ret = i2c_smbus_write_byte_data(client, OV02A10_REG_GAIN, val);
        if (ret < 0)
                return ret;

        return i2c_smbus_write_byte_data(client, REG_GLOBAL_EFFECTIVE,
                                         REG_ENABLE);
}

static int ov02a10_set_vblank(struct ov02a10 *ov02a10, int val)
{
        struct i2c_client *client = v4l2_get_subdevdata(&ov02a10->subdev);
        u32 vts = val + ov02a10->cur_mode->height - OV02A10_BASE_LINES;
        int ret;

        ret = i2c_smbus_write_byte_data(client, REG_PAGE_SWITCH, REG_ENABLE);
        if (ret < 0)
                return ret;

        ret = i2c_smbus_write_byte_data(client, OV02A10_REG_VTS_H,
                                        vts >> OV02A10_VTS_SHIFT);
        if (ret < 0)
                return ret;

        ret = i2c_smbus_write_byte_data(client, OV02A10_REG_VTS_L, vts);
        if (ret < 0)
                return ret;

        return i2c_smbus_write_byte_data(client, REG_GLOBAL_EFFECTIVE,
                                         REG_ENABLE);
}

static int ov02a10_set_test_pattern(struct ov02a10 *ov02a10, int pattern)
{
        struct i2c_client *client = v4l2_get_subdevdata(&ov02a10->subdev);
        int ret;

        ret = i2c_smbus_write_byte_data(client, REG_PAGE_SWITCH, REG_ENABLE);
        if (ret < 0)
                return ret;

        ret = i2c_smbus_write_byte_data(client, OV02A10_REG_TEST_PATTERN,
                                        pattern);
        if (ret < 0)
                return ret;

        ret = i2c_smbus_write_byte_data(client, REG_GLOBAL_EFFECTIVE,
                                        REG_ENABLE);
        if (ret < 0)
                return ret;

        return i2c_smbus_write_byte_data(client, REG_SC_CTRL_MODE,
                                         SC_CTRL_MODE_STREAMING);
}

static int ov02a10_set_ctrl(struct v4l2_ctrl *ctrl)
{
        struct ov02a10 *ov02a10 = container_of(ctrl->handler,
                                               struct ov02a10, ctrl_handler);
        s64 max_expo;
        int ret;

        /* Propagate change of current control to all related controls */
        if (ctrl->id == V4L2_CID_VBLANK) {
                /* Update max exposure while meeting expected vblanking */
                max_expo = ov02a10->cur_mode->height + ctrl->val -
                           OV02A10_EXPOSURE_MAX_MARGIN;
                __v4l2_ctrl_modify_range(ov02a10->exposure,
                                         ov02a10->exposure->minimum, max_expo,
                                         ov02a10->exposure->step,
                                         ov02a10->exposure->default_value);
        }

        /* V4L2 controls values will be applied only when power is already up */
        if (!pm_runtime_get_if_in_use(ov02a10->dev))
                return 0;

        switch (ctrl->id) {
        case V4L2_CID_EXPOSURE:
                ret = ov02a10_set_exposure(ov02a10, ctrl->val);
                break;
        case V4L2_CID_ANALOGUE_GAIN:
                ret = ov02a10_set_gain(ov02a10, ctrl->val);
                break;
        case V4L2_CID_VBLANK:
                ret = ov02a10_set_vblank(ov02a10, ctrl->val);
                break;
        case V4L2_CID_TEST_PATTERN:
                ret = ov02a10_set_test_pattern(ov02a10, ctrl->val);
                break;
        default:
                ret = -EINVAL;
                break;
        }

        pm_runtime_put(ov02a10->dev);

        return ret;
}

static const struct v4l2_subdev_video_ops ov02a10_video_ops = {
        .s_stream = ov02a10_s_stream,
};

static const struct v4l2_subdev_pad_ops ov02a10_pad_ops = {
        .enum_mbus_code = ov02a10_enum_mbus_code,
        .enum_frame_size = ov02a10_enum_frame_sizes,
        .get_fmt = ov02a10_get_fmt,
        .set_fmt = ov02a10_set_fmt,
};

static const struct v4l2_subdev_ops ov02a10_subdev_ops = {
        .video  = &ov02a10_video_ops,
        .pad    = &ov02a10_pad_ops,
};

static const struct v4l2_subdev_internal_ops ov02a10_internal_ops = {
        .init_state = ov02a10_init_state,
};

static const struct media_entity_operations ov02a10_subdev_entity_ops = {
        .link_validate = v4l2_subdev_link_validate,
};

static const struct v4l2_ctrl_ops ov02a10_ctrl_ops = {
        .s_ctrl = ov02a10_set_ctrl,
};

static int ov02a10_initialize_controls(struct ov02a10 *ov02a10)
{
        const struct ov02a10_mode *mode;
        struct v4l2_ctrl_handler *handler;
        struct v4l2_ctrl *ctrl;
        s64 exposure_max;
        s64 vblank_def;
        s64 pixel_rate;
        s64 h_blank;
        int ret;

        handler = &ov02a10->ctrl_handler;
        mode = ov02a10->cur_mode;
        ret = v4l2_ctrl_handler_init(handler, 7);
        if (ret)
                return ret;

        handler->lock = &ov02a10->mutex;

        ctrl = v4l2_ctrl_new_int_menu(handler, NULL, V4L2_CID_LINK_FREQ, 0, 0,
                                      link_freq_menu_items);
        if (ctrl)
                ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;

        pixel_rate = to_pixel_rate(0);
        v4l2_ctrl_new_std(handler, NULL, V4L2_CID_PIXEL_RATE, 0, pixel_rate, 1,
                          pixel_rate);

        h_blank = mode->hts_def - mode->width;
        v4l2_ctrl_new_std(handler, NULL, V4L2_CID_HBLANK, h_blank, h_blank, 1,
                          h_blank);

        vblank_def = mode->vts_def - mode->height;
        v4l2_ctrl_new_std(handler, &ov02a10_ctrl_ops, V4L2_CID_VBLANK,
                          vblank_def, OV02A10_VTS_MAX - mode->height, 1,
                          vblank_def);

        exposure_max = mode->vts_def - 4;
        ov02a10->exposure = v4l2_ctrl_new_std(handler, &ov02a10_ctrl_ops,
                                              V4L2_CID_EXPOSURE,
                                              OV02A10_EXPOSURE_MIN,
                                              exposure_max,
                                              OV02A10_EXPOSURE_STEP,
                                              mode->exp_def);

        v4l2_ctrl_new_std(handler, &ov02a10_ctrl_ops,
                          V4L2_CID_ANALOGUE_GAIN, OV02A10_GAIN_MIN,
                          OV02A10_GAIN_MAX, OV02A10_GAIN_STEP,
                          OV02A10_GAIN_DEFAULT);

        v4l2_ctrl_new_std_menu_items(handler, &ov02a10_ctrl_ops,
                                     V4L2_CID_TEST_PATTERN,
                                     ARRAY_SIZE(ov02a10_test_pattern_menu) - 1,
                                     0, 0, ov02a10_test_pattern_menu);

        if (handler->error) {
                ret = handler->error;
                dev_err(ov02a10->dev, "failed to init controls(%d)\n", ret);
                goto err_free_handler;
        }

        ov02a10->subdev.ctrl_handler = handler;

        return 0;

err_free_handler:
        v4l2_ctrl_handler_free(handler);

        return ret;
}

static int ov02a10_check_hwcfg(struct device *dev, struct ov02a10 *ov02a10)
{
        struct fwnode_handle *ep;
        struct fwnode_handle *fwnode = dev_fwnode(dev);
        struct v4l2_fwnode_endpoint bus_cfg = {
                .bus_type = V4L2_MBUS_CSI2_DPHY,
        };
        unsigned int i, j;
        u32 clk_volt;
        int ret;

        if (!fwnode)
                return -EINVAL;

        ep = fwnode_graph_get_next_endpoint(fwnode, NULL);
        if (!ep)
                return -ENXIO;

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

        /* Optional indication of MIPI clock voltage unit */
        ret = fwnode_property_read_u32(ep, "ovti,mipi-clock-voltage",
                                       &clk_volt);

        if (!ret)
                ov02a10->mipi_clock_voltage = clk_volt;

        for (i = 0; i < ARRAY_SIZE(link_freq_menu_items); i++) {
                for (j = 0; j < bus_cfg.nr_of_link_frequencies; j++) {
                        if (link_freq_menu_items[i] ==
                                bus_cfg.link_frequencies[j])
                                break;
                }

                if (j == bus_cfg.nr_of_link_frequencies) {
                        dev_err(dev, "no link frequency %lld supported\n",
                                link_freq_menu_items[i]);
                        ret = -EINVAL;
                        break;
                }
        }

        v4l2_fwnode_endpoint_free(&bus_cfg);

        return ret;
}

static int ov02a10_probe(struct i2c_client *client)
{
        struct device *dev = &client->dev;
        struct ov02a10 *ov02a10;
        unsigned int i;
        unsigned int rotation;
        int ret;

        ov02a10 = devm_kzalloc(dev, sizeof(*ov02a10), GFP_KERNEL);
        if (!ov02a10)
                return -ENOMEM;

        ov02a10->dev = dev;

        ret = ov02a10_check_hwcfg(dev, ov02a10);
        if (ret)
                return dev_err_probe(dev, ret,
                                     "failed to check HW configuration\n");

        v4l2_i2c_subdev_init(&ov02a10->subdev, client, &ov02a10_subdev_ops);
        ov02a10->subdev.internal_ops = &ov02a10_internal_ops;

        ov02a10->mipi_clock_voltage = OV02A10_MIPI_TX_SPEED_DEFAULT;
        ov02a10->fmt.code = MEDIA_BUS_FMT_SBGGR10_1X10;

        /* Optional indication of physical rotation of sensor */
        rotation = 0;
        device_property_read_u32(dev, "rotation", &rotation);
        if (rotation == 180) {
                ov02a10->upside_down = true;
                ov02a10->fmt.code = MEDIA_BUS_FMT_SRGGB10_1X10;
        }

        ov02a10->eclk = devm_v4l2_sensor_clk_get_legacy(dev, "eclk", false, 0);
        if (IS_ERR(ov02a10->eclk))
                return dev_err_probe(dev, PTR_ERR(ov02a10->eclk),
                                     "failed to get eclk\n");

        if (clk_get_rate(ov02a10->eclk) != OV02A10_ECLK_FREQ)
                dev_warn(dev, "eclk mismatched, mode is based on 24MHz\n");

        ov02a10->pd_gpio = devm_gpiod_get(dev, "powerdown", GPIOD_OUT_HIGH);
        if (IS_ERR(ov02a10->pd_gpio))
                return dev_err_probe(dev, PTR_ERR(ov02a10->pd_gpio),
                                     "failed to get powerdown-gpios\n");

        ov02a10->rst_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
        if (IS_ERR(ov02a10->rst_gpio))
                return dev_err_probe(dev, PTR_ERR(ov02a10->rst_gpio),
                                     "failed to get reset-gpios\n");

        for (i = 0; i < ARRAY_SIZE(ov02a10_supply_names); i++)
                ov02a10->supplies[i].supply = ov02a10_supply_names[i];

        ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ov02a10_supply_names),
                                      ov02a10->supplies);
        if (ret)
                return dev_err_probe(dev, ret, "failed to get regulators\n");

        mutex_init(&ov02a10->mutex);

        /* Set default mode */
        ov02a10->cur_mode = &supported_modes[0];

        ret = ov02a10_initialize_controls(ov02a10);
        if (ret) {
                dev_err_probe(dev, ret, "failed to initialize controls\n");
                goto err_destroy_mutex;
        }

        /* Initialize subdev */
        ov02a10->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
        ov02a10->subdev.entity.ops = &ov02a10_subdev_entity_ops;
        ov02a10->subdev.entity.function = MEDIA_ENT_F_CAM_SENSOR;
        ov02a10->pad.flags = MEDIA_PAD_FL_SOURCE;

        ret = media_entity_pads_init(&ov02a10->subdev.entity, 1, &ov02a10->pad);
        if (ret < 0) {
                dev_err_probe(dev, ret, "failed to initialize entity pads\n");
                goto err_free_handler;
        }

        pm_runtime_enable(dev);
        if (!pm_runtime_enabled(dev)) {
                ret = ov02a10_power_on(dev);
                if (ret < 0) {
                        dev_err_probe(dev, ret, "failed to power on\n");
                        goto err_clean_entity;
                }
        }

        ret = v4l2_async_register_subdev(&ov02a10->subdev);
        if (ret) {
                dev_err_probe(dev, ret, "failed to register V4L2 subdev\n");
                goto err_power_off;
        }

        return 0;

err_power_off:
        if (pm_runtime_enabled(dev))
                pm_runtime_disable(dev);
        else
                ov02a10_power_off(dev);
err_clean_entity:
        media_entity_cleanup(&ov02a10->subdev.entity);
err_free_handler:
        v4l2_ctrl_handler_free(ov02a10->subdev.ctrl_handler);
err_destroy_mutex:
        mutex_destroy(&ov02a10->mutex);

        return ret;
}

static void ov02a10_remove(struct i2c_client *client)
{
        struct v4l2_subdev *sd = i2c_get_clientdata(client);
        struct ov02a10 *ov02a10 = to_ov02a10(sd);

        v4l2_async_unregister_subdev(sd);
        media_entity_cleanup(&sd->entity);
        v4l2_ctrl_handler_free(sd->ctrl_handler);
        pm_runtime_disable(ov02a10->dev);
        if (!pm_runtime_status_suspended(ov02a10->dev))
                ov02a10_power_off(ov02a10->dev);
        pm_runtime_set_suspended(ov02a10->dev);
        mutex_destroy(&ov02a10->mutex);
}

static const struct of_device_id ov02a10_of_match[] = {
        { .compatible = "ovti,ov02a10" },
        {}
};
MODULE_DEVICE_TABLE(of, ov02a10_of_match);

static struct i2c_driver ov02a10_i2c_driver = {
        .driver = {
                .name = "ov02a10",
                .pm = &ov02a10_pm_ops,
                .of_match_table = ov02a10_of_match,
        },
        .probe          = ov02a10_probe,
        .remove         = ov02a10_remove,
};
module_i2c_driver(ov02a10_i2c_driver);

MODULE_AUTHOR("Dongchun Zhu <dongchun.zhu@mediatek.com>");
MODULE_DESCRIPTION("OmniVision OV02A10 sensor driver");
MODULE_LICENSE("GPL v2");