text: /*
   * Support for OmniVision OV2722 1080p HD camera sensor.
   *
   * Copyright (c) 2013 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 <linux/module.h>
  #include <linux/types.h>
  #include <linux/kernel.h>
  #include <linux/mm.h>
  #include <linux/string.h>
  #include <linux/errno.h>
  #include <linux/init.h>
  #include <linux/kmod.h>
  #include <linux/device.h>
  #include <linux/delay.h>
  #include <linux/slab.h>
  #include <linux/i2c.h>
  #include <linux/gpio.h>
  #include <linux/moduleparam.h>
  #include <media/v4l2-device.h>
  #include "../include/linux/atomisp_gmin_platform.h"
  #include <linux/acpi.h>
  #include <linux/io.h>
  
  #include "ov2722.h"
  
  /* i2c read/write stuff */
  static int ov2722_read_reg(struct i2c_client *client,
  			   u16 data_length, u16 reg, u16 *val)
  {
  	int err;
  	struct i2c_msg msg[2];
  	unsigned char data[6];
  
  	if (!client->adapter) {
  		dev_err(&client->dev, "%s error, no client->adapter\n",
  			__func__);
  		return -ENODEV;
  	}
  
  	if (data_length != OV2722_8BIT && data_length != OV2722_16BIT
  					&& data_length != OV2722_32BIT) {
  		dev_err(&client->dev, "%s error, invalid data length\n",
  			__func__);
  		return -EINVAL;
  	}
  
  	memset(msg, 0 , sizeof(msg));
  
  	msg[0].addr = client->addr;
  	msg[0].flags = 0;
  	msg[0].len = I2C_MSG_LENGTH;
  	msg[0].buf = data;
  
  	/* high byte goes out first */
  	data[0] = (u8)(reg >> 8);
  	data[1] = (u8)(reg & 0xff);
  
  	msg[1].addr = client->addr;
  	msg[1].len = data_length;
  	msg[1].flags = I2C_M_RD;
  	msg[1].buf = data;
  
  	err = i2c_transfer(client->adapter, msg, 2);
  	if (err != 2) {
  		if (err >= 0)
  			err = -EIO;
  		dev_err(&client->dev,
  			"read from offset 0x%x error %d", reg, err);
  		return err;
  	}
  
  	*val = 0;
  	/* high byte comes first */
  	if (data_length == OV2722_8BIT)
  		*val = (u8)data[0];
  	else if (data_length == OV2722_16BIT)
  		*val = be16_to_cpu(*(u16 *)&data[0]);
  	else
  		*val = be32_to_cpu(*(u32 *)&data[0]);
  
  	return 0;
  }
  
  static int ov2722_i2c_write(struct i2c_client *client, u16 len, u8 *data)
  {
  	struct i2c_msg msg;
  	const int num_msg = 1;
  	int ret;
  
  	msg.addr = client->addr;
  	msg.flags = 0;
  	msg.len = len;
  	msg.buf = data;
  	ret = i2c_transfer(client->adapter, &msg, 1);
  
  	return ret == num_msg ? 0 : -EIO;
  }
  
  static int ov2722_write_reg(struct i2c_client *client, u16 data_length,
  							u16 reg, u16 val)
  {
  	int ret;
  	unsigned char data[4] = {0};
  	u16 *wreg = (u16 *)data;
  	const u16 len = data_length + sizeof(u16); /* 16-bit address + data */
  
  	if (data_length != OV2722_8BIT && data_length != OV2722_16BIT) {
  		dev_err(&client->dev,
  			"%s error, invalid data_length\n", __func__);
  		return -EINVAL;
  	}
  
  	/* high byte goes out first */
  	*wreg = cpu_to_be16(reg);
  
  	if (data_length == OV2722_8BIT) {
  		data[2] = (u8)(val);
  	} else {
  		/* OV2722_16BIT */
  		u16 *wdata = (u16 *)&data[2];
  		*wdata = cpu_to_be16(val);
  	}
  
  	ret = ov2722_i2c_write(client, len, data);
  	if (ret)
  		dev_err(&client->dev,
  			"write error: wrote 0x%x to offset 0x%x error %d",
  			val, reg, ret);
  
  	return ret;
  }
  
  /*
   * ov2722_write_reg_array - Initializes a list of OV2722 registers
   * @client: i2c driver client structure
   * @reglist: list of registers to be written
   *
   * This function initializes a list of registers. When consecutive addresses
   * are found in a row on the list, this function creates a buffer and sends
   * consecutive data in a single i2c_transfer().
   *
   * __ov2722_flush_reg_array, __ov2722_buf_reg_array() and
   * __ov2722_write_reg_is_consecutive() are internal functions to
   * ov2722_write_reg_array_fast() and should be not used anywhere else.
   *
   */
  
  static int __ov2722_flush_reg_array(struct i2c_client *client,
  				    struct ov2722_write_ctrl *ctrl)
  {
  	u16 size;
  
  	if (ctrl->index == 0)
  		return 0;
  
  	size = sizeof(u16) + ctrl->index; /* 16-bit address + data */
  	ctrl->buffer.addr = cpu_to_be16(ctrl->buffer.addr);
  	ctrl->index = 0;
  
  	return ov2722_i2c_write(client, size, (u8 *)&ctrl->buffer);
  }
  
  static int __ov2722_buf_reg_array(struct i2c_client *client,
  				  struct ov2722_write_ctrl *ctrl,
  				  const struct ov2722_reg *next)
  {
  	int size;
  	u16 *data16;
  
  	switch (next->type) {
  	case OV2722_8BIT:
  		size = 1;
  		ctrl->buffer.data[ctrl->index] = (u8)next->val;
  		break;
  	case OV2722_16BIT:
  		size = 2;
  		data16 = (u16 *)&ctrl->buffer.data[ctrl->index];
  		*data16 = cpu_to_be16((u16)next->val);
  		break;
  	default:
  		return -EINVAL;
  	}
  
  	/* When first item is added, we need to store its starting address */
  	if (ctrl->index == 0)
  		ctrl->buffer.addr = next->reg;
  
  	ctrl->index += size;
  
  	/*
  	 * Buffer cannot guarantee free space for u32? Better flush it to avoid
  	 * possible lack of memory for next item.
  	 */
  	if (ctrl->index + sizeof(u16) >= OV2722_MAX_WRITE_BUF_SIZE)
  		return __ov2722_flush_reg_array(client, ctrl);
  
  	return 0;
  }
  
  static int __ov2722_write_reg_is_consecutive(struct i2c_client *client,
  					     struct ov2722_write_ctrl *ctrl,
  					     const struct ov2722_reg *next)
  {
  	if (ctrl->index == 0)
  		return 1;
  
  	return ctrl->buffer.addr + ctrl->index == next->reg;
  }
  
  static int ov2722_write_reg_array(struct i2c_client *client,
  				  const struct ov2722_reg *reglist)
  {
  	const struct ov2722_reg *next = reglist;
  	struct ov2722_write_ctrl ctrl;
  	int err;
  
  	ctrl.index = 0;
  	for (; next->type != OV2722_TOK_TERM; next++) {
  		switch (next->type & OV2722_TOK_MASK) {
  		case OV2722_TOK_DELAY:
  			err = __ov2722_flush_reg_array(client, &ctrl);
  			if (err)
  				return err;
  			msleep(next->val);
  			break;
  		default:
  			/*
  			 * If next address is not consecutive, data needs to be
  			 * flushed before proceed.
  			 */
  			if (!__ov2722_write_reg_is_consecutive(client, &ctrl,
  								next)) {
  				err = __ov2722_flush_reg_array(client, &ctrl);
  				if (err)
  					return err;
  			}
  			err = __ov2722_buf_reg_array(client, &ctrl, next);
  			if (err) {
  				dev_err(&client->dev, "%s: write error, aborted\n",
  					 __func__);
  				return err;
  			}
  			break;
  		}
  	}
  
  	return __ov2722_flush_reg_array(client, &ctrl);
  }
  static int ov2722_g_focal(struct v4l2_subdev *sd, s32 *val)
  {
  	*val = (OV2722_FOCAL_LENGTH_NUM << 16) | OV2722_FOCAL_LENGTH_DEM;
  	return 0;
  }
  
  static int ov2722_g_fnumber(struct v4l2_subdev *sd, s32 *val)
  {
  	/*const f number for imx*/
  	*val = (OV2722_F_NUMBER_DEFAULT_NUM << 16) | OV2722_F_NUMBER_DEM;
  	return 0;
  }
  
  static int ov2722_g_fnumber_range(struct v4l2_subdev *sd, s32 *val)
  {
  	*val = (OV2722_F_NUMBER_DEFAULT_NUM << 24) |
  		(OV2722_F_NUMBER_DEM << 16) |
  		(OV2722_F_NUMBER_DEFAULT_NUM << 8) | OV2722_F_NUMBER_DEM;
  	return 0;
  }
  
  static int ov2722_get_intg_factor(struct i2c_client *client,
  				struct camera_mipi_info *info,
  				const struct ov2722_resolution *res)
  {
  	struct v4l2_subdev *sd = i2c_get_clientdata(client);
  	struct ov2722_device *dev = NULL;
  	struct atomisp_sensor_mode_data *buf = &info->data;
  	const unsigned int ext_clk_freq_hz = 19200000;
  	const unsigned int pll_invariant_div = 10;
  	unsigned int pix_clk_freq_hz;
  	u16 pre_pll_clk_div;
  	u16 pll_multiplier;
  	u16 op_pix_clk_div;
  	u16 reg_val;
  	int ret;
  
  	if (!info)
  		return -EINVAL;
  
  	dev = to_ov2722_sensor(sd);
  
  	/* pixel clock calculattion */
  	ret =  ov2722_read_reg(client, OV2722_8BIT,
  				OV2722_SC_CMMN_PLL_CTRL3, &pre_pll_clk_div);
  	if (ret)
  		return ret;
  
  	ret =  ov2722_read_reg(client, OV2722_8BIT,
  				OV2722_SC_CMMN_PLL_MULTIPLIER, &pll_multiplier);
  	if (ret)
  		return ret;
  
  	ret =  ov2722_read_reg(client, OV2722_8BIT,
  				OV2722_SC_CMMN_PLL_DEBUG_OPT, &op_pix_clk_div);
  	if (ret)
  		return ret;
  
  	pre_pll_clk_div = (pre_pll_clk_div & 0x70) >> 4;
  	if (0 == pre_pll_clk_div)
  		return -EINVAL;
  
  	pll_multiplier = pll_multiplier & 0x7f;
  	op_pix_clk_div = op_pix_clk_div & 0x03;
  	pix_clk_freq_hz = ext_clk_freq_hz / pre_pll_clk_div * pll_multiplier
  				* op_pix_clk_div / pll_invariant_div;
  
  	dev->vt_pix_clk_freq_mhz = pix_clk_freq_hz;
  	buf->vt_pix_clk_freq_mhz = pix_clk_freq_hz;
  
  	/* get integration time */
  	buf->coarse_integration_time_min = OV2722_COARSE_INTG_TIME_MIN;
  	buf->coarse_integration_time_max_margin =
  					OV2722_COARSE_INTG_TIME_MAX_MARGIN;
  
  	buf->fine_integration_time_min = OV2722_FINE_INTG_TIME_MIN;
  	buf->fine_integration_time_max_margin =
  					OV2722_FINE_INTG_TIME_MAX_MARGIN;
  
  	buf->fine_integration_time_def = OV2722_FINE_INTG_TIME_MIN;
  	buf->frame_length_lines = res->lines_per_frame;
  	buf->line_length_pck = res->pixels_per_line;
  	buf->read_mode = res->bin_mode;
  
  	/* get the cropping and output resolution to ISP for this mode. */
  	ret =  ov2722_read_reg(client, OV2722_16BIT,
  					OV2722_H_CROP_START_H, &reg_val);
  	if (ret)
  		return ret;
  	buf->crop_horizontal_start = reg_val;
  
  	ret =  ov2722_read_reg(client, OV2722_16BIT,
  					OV2722_V_CROP_START_H, &reg_val);
  	if (ret)
  		return ret;
  	buf->crop_vertical_start = reg_val;
  
  	ret = ov2722_read_reg(client, OV2722_16BIT,
  					OV2722_H_CROP_END_H, &reg_val);
  	if (ret)
  		return ret;
  	buf->crop_horizontal_end = reg_val;
  
  	ret = ov2722_read_reg(client, OV2722_16BIT,
  					OV2722_V_CROP_END_H, &reg_val);
  	if (ret)
  		return ret;
  	buf->crop_vertical_end = reg_val;
  
  	ret = ov2722_read_reg(client, OV2722_16BIT,
  					OV2722_H_OUTSIZE_H, &reg_val);
  	if (ret)
  		return ret;
  	buf->output_width = reg_val;
  
  	ret = ov2722_read_reg(client, OV2722_16BIT,
  					OV2722_V_OUTSIZE_H, &reg_val);
  	if (ret)
  		return ret;
  	buf->output_height = reg_val;
  
  	buf->binning_factor_x = res->bin_factor_x ?
  					res->bin_factor_x : 1;
  	buf->binning_factor_y = res->bin_factor_y ?
  					res->bin_factor_y : 1;
  	return 0;
  }
  
  static long __ov2722_set_exposure(struct v4l2_subdev *sd, int coarse_itg,
  				 int gain, int digitgain)
  
  {
  	struct i2c_client *client = v4l2_get_subdevdata(sd);
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  	u16 hts, vts;
  	int ret;
  
  	dev_dbg(&client->dev, "set_exposure without group hold\n");
  
  	/* clear VTS_DIFF on manual mode */
  	ret = ov2722_write_reg(client, OV2722_16BIT, OV2722_VTS_DIFF_H, 0);
  	if (ret)
  		return ret;
  
  	hts = dev->pixels_per_line;
  	vts = dev->lines_per_frame;
  
  	if ((coarse_itg + OV2722_COARSE_INTG_TIME_MAX_MARGIN) > vts)
  		vts = coarse_itg + OV2722_COARSE_INTG_TIME_MAX_MARGIN;
  
  	coarse_itg <<= 4;
  	digitgain <<= 2;
  
  	ret = ov2722_write_reg(client, OV2722_16BIT,
  				OV2722_VTS_H, vts);
  	if (ret)
  		return ret;
  
  	ret = ov2722_write_reg(client, OV2722_16BIT,
  				OV2722_HTS_H, hts);
  	if (ret)
  		return ret;
  
  	/* set exposure */
  	ret = ov2722_write_reg(client, OV2722_8BIT,
  					OV2722_AEC_PK_EXPO_L,
  					coarse_itg & 0xff);
  	if (ret)
  		return ret;
  
  	ret = ov2722_write_reg(client, OV2722_16BIT,
  					OV2722_AEC_PK_EXPO_H,
  					(coarse_itg >> 8) & 0xfff);
  	if (ret)
  		return ret;
  
  	/* set analog gain */
  	ret = ov2722_write_reg(client, OV2722_16BIT,
  					OV2722_AGC_ADJ_H, gain);
  	if (ret)
  		return ret;
  
  	/* set digital gain */
  	ret = ov2722_write_reg(client, OV2722_16BIT,
  				OV2722_MWB_GAIN_R_H, digitgain);
  	if (ret)
  		return ret;
  
  	ret = ov2722_write_reg(client, OV2722_16BIT,
  				OV2722_MWB_GAIN_G_H, digitgain);
  	if (ret)
  		return ret;
  
  	ret = ov2722_write_reg(client, OV2722_16BIT,
  				OV2722_MWB_GAIN_B_H, digitgain);
  
  	return ret;
  }
  
  static int ov2722_set_exposure(struct v4l2_subdev *sd, int exposure,
  	int gain, int digitgain)
  {
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  	int ret;
  
  	mutex_lock(&dev->input_lock);
  	ret = __ov2722_set_exposure(sd, exposure, gain, digitgain);
  	mutex_unlock(&dev->input_lock);
  
  	return ret;
  }
  
  static long ov2722_s_exposure(struct v4l2_subdev *sd,
  			       struct atomisp_exposure *exposure)
  {
  	int exp = exposure->integration_time[0];
  	int gain = exposure->gain[0];
  	int digitgain = exposure->gain[1];
  
  	/* we should not accept the invalid value below. */
  	if (gain == 0) {
  		struct i2c_client *client = v4l2_get_subdevdata(sd);
  		v4l2_err(client, "%s: invalid value\n", __func__);
  		return -EINVAL;
  	}
  
  	return ov2722_set_exposure(sd, exp, gain, digitgain);
  }
  
  static long ov2722_ioctl(struct v4l2_subdev *sd, unsigned int cmd, void *arg)
  {
  
  	switch (cmd) {
  	case ATOMISP_IOC_S_EXPOSURE:
  		return ov2722_s_exposure(sd, arg);
  	default:
  		return -EINVAL;
  	}
  	return 0;
  }
  
  /* This returns the exposure time being used. This should only be used
   * for filling in EXIF data, not for actual image processing.
   */
  static int ov2722_q_exposure(struct v4l2_subdev *sd, s32 *value)
  {
  	struct i2c_client *client = v4l2_get_subdevdata(sd);
  	u16 reg_v, reg_v2;
  	int ret;
  
  	/* get exposure */
  	ret = ov2722_read_reg(client, OV2722_8BIT,
  					OV2722_AEC_PK_EXPO_L,
  					&reg_v);
  	if (ret)
  		goto err;
  
  	ret = ov2722_read_reg(client, OV2722_8BIT,
  					OV2722_AEC_PK_EXPO_M,
  					&reg_v2);
  	if (ret)
  		goto err;
  
  	reg_v += reg_v2 << 8;
  	ret = ov2722_read_reg(client, OV2722_8BIT,
  					OV2722_AEC_PK_EXPO_H,
  					&reg_v2);
  	if (ret)
  		goto err;
  
  	*value = reg_v + (((u32)reg_v2 << 16));
  err:
  	return ret;
  }
  
  static int ov2722_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
  {
  	struct ov2722_device *dev =
  	    container_of(ctrl->handler, struct ov2722_device, ctrl_handler);
  	int ret = 0;
  	unsigned int val;
  	switch (ctrl->id) {
  	case V4L2_CID_EXPOSURE_ABSOLUTE:
  		ret = ov2722_q_exposure(&dev->sd, &ctrl->val);
  		break;
  	case V4L2_CID_FOCAL_ABSOLUTE:
  		ret = ov2722_g_focal(&dev->sd, &ctrl->val);
  		break;
  	case V4L2_CID_FNUMBER_ABSOLUTE:
  		ret = ov2722_g_fnumber(&dev->sd, &ctrl->val);
  		break;
  	case V4L2_CID_FNUMBER_RANGE:
  		ret = ov2722_g_fnumber_range(&dev->sd, &ctrl->val);
  		break;
  	case V4L2_CID_LINK_FREQ:
  		val = ov2722_res[dev->fmt_idx].mipi_freq;
  		if (val == 0)
  			return -EINVAL;
  
  		ctrl->val = val * 1000;	/* To Hz */
  		break;
  	default:
  		ret = -EINVAL;
  	}
  
  	return ret;
  }
  
  static const struct v4l2_ctrl_ops ctrl_ops = {
  	.g_volatile_ctrl = ov2722_g_volatile_ctrl
  };
  
  struct v4l2_ctrl_config ov2722_controls[] = {
  	{
  	 .ops = &ctrl_ops,
  	 .id = V4L2_CID_EXPOSURE_ABSOLUTE,
  	 .type = V4L2_CTRL_TYPE_INTEGER,
  	 .name = "exposure",
  	 .min = 0x0,
  	 .max = 0xffff,
  	 .step = 0x01,
  	 .def = 0x00,
  	 .flags = 0,
  	 },
  	{
  	 .ops = &ctrl_ops,
  	 .id = V4L2_CID_FOCAL_ABSOLUTE,
  	 .type = V4L2_CTRL_TYPE_INTEGER,
  	 .name = "focal length",
  	 .min = OV2722_FOCAL_LENGTH_DEFAULT,
  	 .max = OV2722_FOCAL_LENGTH_DEFAULT,
  	 .step = 0x01,
  	 .def = OV2722_FOCAL_LENGTH_DEFAULT,
  	 .flags = 0,
  	 },
  	{
  	 .ops = &ctrl_ops,
  	 .id = V4L2_CID_FNUMBER_ABSOLUTE,
  	 .type = V4L2_CTRL_TYPE_INTEGER,
  	 .name = "f-number",
  	 .min = OV2722_F_NUMBER_DEFAULT,
  	 .max = OV2722_F_NUMBER_DEFAULT,
  	 .step = 0x01,
  	 .def = OV2722_F_NUMBER_DEFAULT,
  	 .flags = 0,
  	 },
  	{
  	 .ops = &ctrl_ops,
  	 .id = V4L2_CID_FNUMBER_RANGE,
  	 .type = V4L2_CTRL_TYPE_INTEGER,
  	 .name = "f-number range",
  	 .min = OV2722_F_NUMBER_RANGE,
  	 .max = OV2722_F_NUMBER_RANGE,
  	 .step = 0x01,
  	 .def = OV2722_F_NUMBER_RANGE,
  	 .flags = 0,
  	 },
  	{
  	 .ops = &ctrl_ops,
  	 .id = V4L2_CID_LINK_FREQ,
  	 .name = "Link Frequency",
  	 .type = V4L2_CTRL_TYPE_INTEGER,
  	 .min = 1,
  	 .max = 1500000 * 1000,
  	 .step = 1,
  	 .def = 1,
  	 .flags = V4L2_CTRL_FLAG_VOLATILE | V4L2_CTRL_FLAG_READ_ONLY,
  	 },
  };
  
  static int ov2722_init(struct v4l2_subdev *sd)
  {
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  
  	mutex_lock(&dev->input_lock);
  
  	/* restore settings */
  	ov2722_res = ov2722_res_preview;
  	N_RES = N_RES_PREVIEW;
  
  	mutex_unlock(&dev->input_lock);
  
  	return 0;
  }
  
  static int power_ctrl(struct v4l2_subdev *sd, bool flag)
  {
  	int ret = -1;
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  
  	if (!dev || !dev->platform_data)
  		return -ENODEV;
  
  	/* Non-gmin platforms use the legacy callback */
  	if (dev->platform_data->power_ctrl)
  		return dev->platform_data->power_ctrl(sd, flag);
  
  	if (flag) {
  		ret = dev->platform_data->v1p8_ctrl(sd, 1);
  		if (ret == 0) {
  			ret = dev->platform_data->v2p8_ctrl(sd, 1);
  			if (ret)
  				dev->platform_data->v1p8_ctrl(sd, 0);
  		}
  	} else {
  		ret = dev->platform_data->v1p8_ctrl(sd, 0);
  		ret |= dev->platform_data->v2p8_ctrl(sd, 0);
  	}
  
  	return ret;
  }
  
  static int gpio_ctrl(struct v4l2_subdev *sd, bool flag)
  {
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  	int ret = -1;
  
  	if (!dev || !dev->platform_data)
  		return -ENODEV;
  
  	/* Non-gmin platforms use the legacy callback */
  	if (dev->platform_data->gpio_ctrl)
  		return dev->platform_data->gpio_ctrl(sd, flag);
  
  	/* Note: the GPIO order is asymmetric: always RESET#
  	 * before PWDN# when turning it on or off.
  	 */
  	ret = dev->platform_data->gpio0_ctrl(sd, flag);
  	/*
  	 *ov2722 PWDN# active high when pull down,opposite to the convention
  	 */
  	ret |= dev->platform_data->gpio1_ctrl(sd, !flag);
  	return ret;
  }
  
  static int power_up(struct v4l2_subdev *sd)
  {
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  	struct i2c_client *client = v4l2_get_subdevdata(sd);
  	int ret;
  
  	if (!dev->platform_data) {
  		dev_err(&client->dev,
  			"no camera_sensor_platform_data");
  		return -ENODEV;
  	}
  
  	/* power control */
  	ret = power_ctrl(sd, 1);
  	if (ret)
  		goto fail_power;
  
  	/* according to DS, at least 5ms is needed between DOVDD and PWDN */
  	usleep_range(5000, 6000);
  
  	/* gpio ctrl */
  	ret = gpio_ctrl(sd, 1);
  	if (ret) {
  		ret = gpio_ctrl(sd, 0);
  		if (ret)
  			goto fail_power;
  	}
  
  	/* flis clock control */
  	ret = dev->platform_data->flisclk_ctrl(sd, 1);
  	if (ret)
  		goto fail_clk;
  
  	/* according to DS, 20ms is needed between PWDN and i2c access */
  	msleep(20);
  
  	return 0;
  
  fail_clk:
  	gpio_ctrl(sd, 0);
  fail_power:
  	power_ctrl(sd, 0);
  	dev_err(&client->dev, "sensor power-up failed\n");
  
  	return ret;
  }
  
  static int power_down(struct v4l2_subdev *sd)
  {
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  	struct i2c_client *client = v4l2_get_subdevdata(sd);
  	int ret = 0;
  
  	if (!dev->platform_data) {
  		dev_err(&client->dev,
  			"no camera_sensor_platform_data");
  		return -ENODEV;
  	}
  
  	ret = dev->platform_data->flisclk_ctrl(sd, 0);
  	if (ret)
  		dev_err(&client->dev, "flisclk failed\n");
  
  	/* gpio ctrl */
  	ret = gpio_ctrl(sd, 0);
  	if (ret) {
  		ret = gpio_ctrl(sd, 0);
  		if (ret)
  			dev_err(&client->dev, "gpio failed 2\n");
  	}
  
  	/* power control */
  	ret = power_ctrl(sd, 0);
  	if (ret)
  		dev_err(&client->dev, "vprog failed.\n");
  
  	return ret;
  }
  
  static int ov2722_s_power(struct v4l2_subdev *sd, int on)
  {
  	int ret;
  	if (on == 0)
  		return power_down(sd);
  	else {
  		ret = power_up(sd);
  		if (!ret)
  			return ov2722_init(sd);
  	}
  	return ret;
  }
  
  /*
   * distance - calculate the distance
   * @res: resolution
   * @w: width
   * @h: height
   *
   * Get the gap between resolution and w/h.
   * res->width/height smaller than w/h wouldn't be considered.
   * Returns the value of gap or -1 if fail.
   */
  #define LARGEST_ALLOWED_RATIO_MISMATCH 800
  static int distance(struct ov2722_resolution *res, u32 w, u32 h)
  {
  	unsigned int w_ratio = (res->width << 13) / w;
  	unsigned int h_ratio;
  	int match;
  
  	if (h == 0)
  		return -1;
  	h_ratio = (res->height << 13) / h;
  	if (h_ratio == 0)
  		return -1;
  	match   = abs(((w_ratio << 13) / h_ratio) - 8192);
  
  	if ((w_ratio < 8192) || (h_ratio < 8192) ||
  	    (match > LARGEST_ALLOWED_RATIO_MISMATCH))
  		return -1;
  
  	return w_ratio + h_ratio;
  }
  
  /* Return the nearest higher resolution index */
  static int nearest_resolution_index(int w, int h)
  {
  	int i;
  	int idx = -1;
  	int dist;
  	int min_dist = INT_MAX;
  	struct ov2722_resolution *tmp_res = NULL;
  
  	for (i = 0; i < N_RES; i++) {
  		tmp_res = &ov2722_res[i];
  		dist = distance(tmp_res, w, h);
  		if (dist == -1)
  			continue;
  		if (dist < min_dist) {
  			min_dist = dist;
  			idx = i;
  		}
  	}
  
  	return idx;
  }
  
  static int get_resolution_index(int w, int h)
  {
  	int i;
  
  	for (i = 0; i < N_RES; i++) {
  		if (w != ov2722_res[i].width)
  			continue;
  		if (h != ov2722_res[i].height)
  			continue;
  
  		return i;
  	}
  
  	return -1;
  }
  
  /* TODO: remove it. */
  static int startup(struct v4l2_subdev *sd)
  {
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  	struct i2c_client *client = v4l2_get_subdevdata(sd);
  	int ret = 0;
  
  	ret = ov2722_write_reg(client, OV2722_8BIT,
  					OV2722_SW_RESET, 0x01);
  	if (ret) {
  		dev_err(&client->dev, "ov2722 reset err.\n");
  		return ret;
  	}
  
  	ret = ov2722_write_reg_array(client, ov2722_res[dev->fmt_idx].regs);
  	if (ret) {
  		dev_err(&client->dev, "ov2722 write register err.\n");
  		return ret;
  	}
  
  	return ret;
  }
  
  static int ov2722_set_fmt(struct v4l2_subdev *sd,
  			  struct v4l2_subdev_pad_config *cfg,
  			  struct v4l2_subdev_format *format)
  {
  	struct v4l2_mbus_framefmt *fmt = &format->format;
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  	struct i2c_client *client = v4l2_get_subdevdata(sd);
  	struct camera_mipi_info *ov2722_info = NULL;
  	int ret = 0;
  	int idx;
  	if (format->pad)
  		return -EINVAL;
  	if (!fmt)
  		return -EINVAL;
  	ov2722_info = v4l2_get_subdev_hostdata(sd);
  	if (!ov2722_info)
  		return -EINVAL;
  
  	mutex_lock(&dev->input_lock);
  	idx = nearest_resolution_index(fmt->width, fmt->height);
  	if (idx == -1) {
  		/* return the largest resolution */
  		fmt->width = ov2722_res[N_RES - 1].width;
  		fmt->height = ov2722_res[N_RES - 1].height;
  	} else {
  		fmt->width = ov2722_res[idx].width;
  		fmt->height = ov2722_res[idx].height;
  	}
  	fmt->code = MEDIA_BUS_FMT_SGRBG10_1X10;
  	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
  		cfg->try_fmt = *fmt;
  		mutex_unlock(&dev->input_lock);
  		return 0;
  	}
  
  	dev->fmt_idx = get_resolution_index(fmt->width, fmt->height);
  	if (dev->fmt_idx == -1) {
  		dev_err(&client->dev, "get resolution fail\n");
  		mutex_unlock(&dev->input_lock);
  		return -EINVAL;
  	}
  
  	dev->pixels_per_line = ov2722_res[dev->fmt_idx].pixels_per_line;
  	dev->lines_per_frame = ov2722_res[dev->fmt_idx].lines_per_frame;
  
  	ret = startup(sd);
  	if (ret) {
  		int i = 0;
  		dev_err(&client->dev, "ov2722 startup err, retry to power up\n");
  		for (i = 0; i < OV2722_POWER_UP_RETRY_NUM; i++) {
  			dev_err(&client->dev,
  				"ov2722 retry to power up %d/%d times, result: ",
  				i + 1, OV2722_POWER_UP_RETRY_NUM);
  			power_down(sd);
  			ret = power_up(sd);
  			if (ret) {
  				dev_err(&client->dev, "power up failed, continue\n");
  				continue;
  			}
  			ret = startup(sd);
  			if (ret) {
  				dev_err(&client->dev, " startup FAILED!\n");
  			} else {
  				dev_err(&client->dev, " startup SUCCESS!\n");
  				break;
  			}
  		}
  		if (ret) {
  			dev_err(&client->dev, "ov2722 startup err\n");
  			goto err;
  		}
  	}
  
  	ret = ov2722_get_intg_factor(client, ov2722_info,
  					&ov2722_res[dev->fmt_idx]);
  	if (ret)
  		dev_err(&client->dev, "failed to get integration_factor\n");
  
  err:
  	mutex_unlock(&dev->input_lock);
  	return ret;
  }
  static int ov2722_get_fmt(struct v4l2_subdev *sd,
  			  struct v4l2_subdev_pad_config *cfg,
  			  struct v4l2_subdev_format *format)
  {
  	struct v4l2_mbus_framefmt *fmt = &format->format;
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  
  	if (format->pad)
  		return -EINVAL;
  	if (!fmt)
  		return -EINVAL;
  
  	fmt->width = ov2722_res[dev->fmt_idx].width;
  	fmt->height = ov2722_res[dev->fmt_idx].height;
  	fmt->code = MEDIA_BUS_FMT_SBGGR10_1X10;
  
  	return 0;
  }
  
  static int ov2722_detect(struct i2c_client *client)
  {
  	struct i2c_adapter *adapter = client->adapter;
  	u16 high, low;
  	int ret;
  	u16 id;
  	u8 revision;
  
  	if (!i2c_check_functionality(adapter, I2C_FUNC_I2C))
  		return -ENODEV;
  
  	ret = ov2722_read_reg(client, OV2722_8BIT,
  					OV2722_SC_CMMN_CHIP_ID_H, &high);
  	if (ret) {
  		dev_err(&client->dev, "sensor_id_high = 0x%x\n", high);
  		return -ENODEV;
  	}
  	ret = ov2722_read_reg(client, OV2722_8BIT,
  					OV2722_SC_CMMN_CHIP_ID_L, &low);
  	id = (high << 8) | low;
  
  	if ((id != OV2722_ID) && (id != OV2720_ID)) {
  		dev_err(&client->dev, "sensor ID error\n");
  		return -ENODEV;
  	}
  
  	ret = ov2722_read_reg(client, OV2722_8BIT,
  					OV2722_SC_CMMN_SUB_ID, &high);
  	revision = (u8) high & 0x0f;
  
  	dev_dbg(&client->dev, "sensor_revision = 0x%x\n", revision);
  	dev_dbg(&client->dev, "detect ov2722 success\n");
  	return 0;
  }
  
  static int ov2722_s_stream(struct v4l2_subdev *sd, int enable)
  {
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  	struct i2c_client *client = v4l2_get_subdevdata(sd);
  	int ret;
  
  	mutex_lock(&dev->input_lock);
  
  	ret = ov2722_write_reg(client, OV2722_8BIT, OV2722_SW_STREAM,
  				enable ? OV2722_START_STREAMING :
  				OV2722_STOP_STREAMING);
  
  	mutex_unlock(&dev->input_lock);
  	return ret;
  }
  
  static int ov2722_s_config(struct v4l2_subdev *sd,
  			   int irq, void *platform_data)
  {
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  	struct i2c_client *client = v4l2_get_subdevdata(sd);
  	int ret = 0;
  
  	if (!platform_data)
  		return -ENODEV;
  
  	dev->platform_data =
  		(struct camera_sensor_platform_data *)platform_data;
  
  	mutex_lock(&dev->input_lock);
  	if (dev->platform_data->platform_init) {
  		ret = dev->platform_data->platform_init(client);
  		if (ret) {
  			dev_err(&client->dev, "platform init err\n");
  			goto platform_init_failed;
  		}
  	}
  
  	/* power off the module, then power on it in future
  	 * as first power on by board may not fulfill the
  	 * power on sequqence needed by the module
  	 */
  	ret = power_down(sd);
  	if (ret) {
  		dev_err(&client->dev, "ov2722 power-off err.\n");
  		goto fail_power_off;
  	}
  
  	ret = power_up(sd);
  	if (ret) {
  		dev_err(&client->dev, "ov2722 power-up err.\n");
  		goto fail_power_on;
  	}
  
  	ret = dev->platform_data->csi_cfg(sd, 1);
  	if (ret)
  		goto fail_csi_cfg;
  
  	/* config & detect sensor */
  	ret = ov2722_detect(client);
  	if (ret) {
  		dev_err(&client->dev, "ov2722_detect err s_config.\n");
  		goto fail_csi_cfg;
  	}
  
  	/* turn off sensor, after probed */
  	ret = power_down(sd);
  	if (ret) {
  		dev_err(&client->dev, "ov2722 power-off err.\n");
  		goto fail_csi_cfg;
  	}
  	mutex_unlock(&dev->input_lock);
  
  	return 0;
  
  fail_csi_cfg:
  	dev->platform_data->csi_cfg(sd, 0);
  fail_power_on:
  	power_down(sd);
  	dev_err(&client->dev, "sensor power-gating failed\n");
  fail_power_off:
  	if (dev->platform_data->platform_deinit)
  		dev->platform_data->platform_deinit();
  platform_init_failed:
  	mutex_unlock(&dev->input_lock);
  	return ret;
  }
  
  static int ov2722_g_parm(struct v4l2_subdev *sd,
  			struct v4l2_streamparm *param)
  {
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  	struct i2c_client *client = v4l2_get_subdevdata(sd);
  
  	if (!param)
  		return -EINVAL;
  
  	if (param->type != V4L2_BUF_TYPE_VIDEO_CAPTURE) {
  		dev_err(&client->dev,  "unsupported buffer type.\n");
  		return -EINVAL;
  	}
  
  	memset(param, 0, sizeof(*param));
  	param->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
  
  	if (dev->fmt_idx >= 0 && dev->fmt_idx < N_RES) {
  		param->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
  		param->parm.capture.timeperframe.numerator = 1;
  		param->parm.capture.capturemode = dev->run_mode;
  		param->parm.capture.timeperframe.denominator =
  			ov2722_res[dev->fmt_idx].fps;
  	}
  	return 0;
  }
  
  static int ov2722_s_parm(struct v4l2_subdev *sd,
  			struct v4l2_streamparm *param)
  {
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  	dev->run_mode = param->parm.capture.capturemode;
  
  	mutex_lock(&dev->input_lock);
  	switch (dev->run_mode) {
  	case CI_MODE_VIDEO:
  		ov2722_res = ov2722_res_video;
  		N_RES = N_RES_VIDEO;
  		break;
  	case CI_MODE_STILL_CAPTURE:
  		ov2722_res = ov2722_res_still;
  		N_RES = N_RES_STILL;
  		break;
  	default:
  		ov2722_res = ov2722_res_preview;
  		N_RES = N_RES_PREVIEW;
  	}
  	mutex_unlock(&dev->input_lock);
  	return 0;
  }
  
  static int ov2722_g_frame_interval(struct v4l2_subdev *sd,
  				   struct v4l2_subdev_frame_interval *interval)
  {
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  
  	interval->interval.numerator = 1;
  	interval->interval.denominator = ov2722_res[dev->fmt_idx].fps;
  
  	return 0;
  }
  
  static int ov2722_enum_mbus_code(struct v4l2_subdev *sd,
  				 struct v4l2_subdev_pad_config *cfg,
  				 struct v4l2_subdev_mbus_code_enum *code)
  {
  	if (code->index >= MAX_FMTS)
  		return -EINVAL;
  
  	code->code = MEDIA_BUS_FMT_SBGGR10_1X10;
  	return 0;
  }
  
  static int ov2722_enum_frame_size(struct v4l2_subdev *sd,
  				  struct v4l2_subdev_pad_config *cfg,
  				  struct v4l2_subdev_frame_size_enum *fse)
  {
  	int index = fse->index;
  
  	if (index >= N_RES)
  		return -EINVAL;
  
  	fse->min_width = ov2722_res[index].width;
  	fse->min_height = ov2722_res[index].height;
  	fse->max_width = ov2722_res[index].width;
  	fse->max_height = ov2722_res[index].height;
  
  	return 0;
  
  }
  
  
  static int ov2722_g_skip_frames(struct v4l2_subdev *sd, u32 *frames)
  {
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  
  	mutex_lock(&dev->input_lock);
  	*frames = ov2722_res[dev->fmt_idx].skip_frames;
  	mutex_unlock(&dev->input_lock);
  
  	return 0;
  }
  
  static const struct v4l2_subdev_sensor_ops ov2722_sensor_ops = {
  	.g_skip_frames	= ov2722_g_skip_frames,
  };
  
  static const struct v4l2_subdev_video_ops ov2722_video_ops = {
  	.s_stream = ov2722_s_stream,
  	.g_parm = ov2722_g_parm,
  	.s_parm = ov2722_s_parm,
  	.g_frame_interval = ov2722_g_frame_interval,
  };
  
  static const struct v4l2_subdev_core_ops ov2722_core_ops = {
  	.s_power = ov2722_s_power,
  	.ioctl = ov2722_ioctl,
  };
  
  static const struct v4l2_subdev_pad_ops ov2722_pad_ops = {
  	.enum_mbus_code = ov2722_enum_mbus_code,
  	.enum_frame_size = ov2722_enum_frame_size,
  	.get_fmt = ov2722_get_fmt,
  	.set_fmt = ov2722_set_fmt,
  };
  
  static const struct v4l2_subdev_ops ov2722_ops = {
  	.core = &ov2722_core_ops,
  	.video = &ov2722_video_ops,
  	.pad = &ov2722_pad_ops,
  	.sensor = &ov2722_sensor_ops,
  };
  
  static int ov2722_remove(struct i2c_client *client)
  {
  	struct v4l2_subdev *sd = i2c_get_clientdata(client);
  	struct ov2722_device *dev = to_ov2722_sensor(sd);
  	dev_dbg(&client->dev, "ov2722_remove...\n");
  
  	if (dev->platform_data->platform_deinit)
  		dev->platform_data->platform_deinit();
  
  	dev->platform_data->csi_cfg(sd, 0);
  	v4l2_ctrl_handler_free(&dev->ctrl_handler);
  	v4l2_device_unregister_subdev(sd);
  
  	atomisp_gmin_remove_subdev(sd);
  
  	media_entity_cleanup(&dev->sd.entity);
  	kfree(dev);
  
  	return 0;
  }
  
  static int __ov2722_init_ctrl_handler(struct ov2722_device *dev)
  {
  	struct v4l2_ctrl_handler *hdl;
  	unsigned int i;
  	hdl = &dev->ctrl_handler;
  	v4l2_ctrl_handler_init(&dev->ctrl_handler, ARRAY_SIZE(ov2722_controls));
  	for (i = 0; i < ARRAY_SIZE(ov2722_controls); i++)
  		v4l2_ctrl_new_custom(&dev->ctrl_handler, &ov2722_controls[i],
  				     NULL);
  
  	dev->link_freq = v4l2_ctrl_find(&dev->ctrl_handler, V4L2_CID_LINK_FREQ);
  
  	if (dev->ctrl_handler.error || !dev->link_freq)
  		return dev->ctrl_handler.error;
  
  	dev->sd.ctrl_handler = hdl;
  
  	return 0;
  }
  
  static int ov2722_probe(struct i2c_client *client,
  			const struct i2c_device_id *id)
  {
  	struct ov2722_device *dev;
  	void *ovpdev;
  	int ret;
  	struct acpi_device *adev;
  
  	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
  	if (!dev) {
  		dev_err(&client->dev, "out of memory\n");
  		return -ENOMEM;
  	}
  
  	mutex_init(&dev->input_lock);
  
  	dev->fmt_idx = 0;
  	v4l2_i2c_subdev_init(&(dev->sd), client, &ov2722_ops);
  
  	ovpdev = client->dev.platform_data;
  	adev = ACPI_COMPANION(&client->dev);
  	if (adev) {
  		adev->power.flags.power_resources = 0;
  		ovpdev = gmin_camera_platform_data(&dev->sd,
  						   ATOMISP_INPUT_FORMAT_RAW_10,
  						   atomisp_bayer_order_grbg);
  	}
  
  	ret = ov2722_s_config(&dev->sd, client->irq, ovpdev);
  	if (ret)
  		goto out_free;
  
  	ret = __ov2722_init_ctrl_handler(dev);
  	if (ret)
  		goto out_ctrl_handler_free;
  
  	dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
  	dev->pad.flags = MEDIA_PAD_FL_SOURCE;
  	dev->format.code = MEDIA_BUS_FMT_SBGGR10_1X10;
  	dev->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
  
  	ret = media_entity_pads_init(&dev->sd.entity, 1, &dev->pad);
  	if (ret)
  		ov2722_remove(client);
  
  	if (ACPI_HANDLE(&client->dev))
  		ret = atomisp_register_i2c_module(&dev->sd, ovpdev, RAW_CAMERA);
  
  	return ret;
  
  out_ctrl_handler_free:
  	v4l2_ctrl_handler_free(&dev->ctrl_handler);
  
  out_free:
  	v4l2_device_unregister_subdev(&dev->sd);
  	kfree(dev);
  	return ret;
  }
  
  MODULE_DEVICE_TABLE(i2c, ov2722_id);
  
  static struct acpi_device_id ov2722_acpi_match[] = {
  	{ "INT33FB" },
  	{},
  };
  
  MODULE_DEVICE_TABLE(acpi, ov2722_acpi_match);
  
  static struct i2c_driver ov2722_driver = {
  	.driver = {
  		.name = OV2722_NAME,
  		.acpi_match_table = ACPI_PTR(ov2722_acpi_match),
  	},
  	.probe = ov2722_probe,
  	.remove = ov2722_remove,
  	.id_table = ov2722_id,
  };
  
  static int init_ov2722(void)
  {
  	return i2c_add_driver(&ov2722_driver);
  }
  
  static void exit_ov2722(void)
  {
  
  	i2c_del_driver(&ov2722_driver);
  }
  
  module_init(init_ov2722);
  module_exit(exit_ov2722);
  
  MODULE_AUTHOR("Wei Liu <wei.liu@intel.com>");
  MODULE_DESCRIPTION("A low-level driver for OmniVision 2722 sensors");
  MODULE_LICENSE("GPL");
  