drivers/media/i2c/saa7191.c - maze/linux - Git at Google

 /*
  *  saa7191.c - Philips SAA7191 video decoder driver
  *
  *  Copyright (C) 2003 Ladislav Michl <ladis@linux-mips.org>
  *  Copyright (C) 2004,2005 Mikael Nousiainen <tmnousia@cc.hut.fi>
  *
  *  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.
  */

 #include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/fs.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/major.h>
 #include <linux/module.h>
 #include <linux/mm.h>
 #include <linux/slab.h>

 #include <linux/videodev2.h>
 #include <linux/i2c.h>
 #include <media/v4l2-device.h>

 #include "saa7191.h"

 #define SAA7191_MODULE_VERSION	"0.0.5"

 MODULE_DESCRIPTION("Philips SAA7191 video decoder driver");
 MODULE_VERSION(SAA7191_MODULE_VERSION);
 MODULE_AUTHOR("Mikael Nousiainen <tmnousia@cc.hut.fi>");
 MODULE_LICENSE("GPL");


 // #define SAA7191_DEBUG

 #ifdef SAA7191_DEBUG
 #define dprintk(x...) printk("SAA7191: " x);
 #else
 #define dprintk(x...)
 #endif

 #define SAA7191_SYNC_COUNT	30
 #define SAA7191_SYNC_DELAY	100	/* milliseconds */

 struct saa7191 {
 	struct v4l2_subdev sd;

 	/* the register values are stored here as the actual
 	 * I2C-registers are write-only */
 	u8 reg[25];

 	int input;
 	v4l2_std_id norm;
 };

 static inline struct saa7191 *to_saa7191(struct v4l2_subdev *sd)
 {
 	return container_of(sd, struct saa7191, sd);
 }

 static const u8 initseq[] = {
 	0,	/* Subaddress */

 	0x50,	/* (0x50) SAA7191_REG_IDEL */

 	/* 50 Hz signal timing */
 	0x30,	/* (0x30) SAA7191_REG_HSYB */
 	0x00,	/* (0x00) SAA7191_REG_HSYS */
 	0xe8,	/* (0xe8) SAA7191_REG_HCLB */
 	0xb6,	/* (0xb6) SAA7191_REG_HCLS */
 	0xf4,	/* (0xf4) SAA7191_REG_HPHI */

 	/* control */
 	SAA7191_LUMA_APER_1,	/* (0x01) SAA7191_REG_LUMA - CVBS mode */
 	0x00,	/* (0x00) SAA7191_REG_HUEC */
 	0xf8,	/* (0xf8) SAA7191_REG_CKTQ */
 	0xf8,	/* (0xf8) SAA7191_REG_CKTS */
 	0x90,	/* (0x90) SAA7191_REG_PLSE */
 	0x90,	/* (0x90) SAA7191_REG_SESE */
 	0x00,	/* (0x00) SAA7191_REG_GAIN */
 	SAA7191_STDC_NFEN | SAA7191_STDC_HRMV,	/* (0x0c) SAA7191_REG_STDC
 						 * - not SECAM,
 						 * slow time constant */
 	SAA7191_IOCK_OEDC | SAA7191_IOCK_OEHS | SAA7191_IOCK_OEVS
 	| SAA7191_IOCK_OEDY,	/* (0x78) SAA7191_REG_IOCK
 				 * - chroma from CVBS, GPSW1 & 2 off */
 	SAA7191_CTL3_AUFD | SAA7191_CTL3_SCEN | SAA7191_CTL3_OFTS
 	| SAA7191_CTL3_YDEL0,	/* (0x99) SAA7191_REG_CTL3
 				 * - automatic field detection */
 	0x00,	/* (0x00) SAA7191_REG_CTL4 */
 	0x2c,	/* (0x2c) SAA7191_REG_CHCV - PAL nominal value */
 	0x00,	/* unused */
 	0x00,	/* unused */

 	/* 60 Hz signal timing */
 	0x34,	/* (0x34) SAA7191_REG_HS6B */
 	0x0a,	/* (0x0a) SAA7191_REG_HS6S */
 	0xf4,	/* (0xf4) SAA7191_REG_HC6B */
 	0xce,	/* (0xce) SAA7191_REG_HC6S */
 	0xf4,	/* (0xf4) SAA7191_REG_HP6I */
 };

 /* SAA7191 register handling */

 static u8 saa7191_read_reg(struct v4l2_subdev *sd, u8 reg)
 {
 	return to_saa7191(sd)->reg[reg];
 }

 static int saa7191_read_status(struct v4l2_subdev *sd, u8 *value)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(sd);
 	int ret;

 	ret = i2c_master_recv(client, value, 1);
 	if (ret < 0) {
 		printk(KERN_ERR "SAA7191: saa7191_read_status(): read failed\n");
 		return ret;
 	}

 	return 0;
 }


 static int saa7191_write_reg(struct v4l2_subdev *sd, u8 reg, u8 value)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(sd);

 	to_saa7191(sd)->reg[reg] = value;
 	return i2c_smbus_write_byte_data(client, reg, value);
 }

 /* the first byte of data must be the first subaddress number (register) */
 static int saa7191_write_block(struct v4l2_subdev *sd,
 			       u8 length, const u8 *data)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(sd);
 	struct saa7191 *decoder = to_saa7191(sd);
 	int i;
 	int ret;

 	for (i = 0; i < (length - 1); i++) {
 		decoder->reg[data[0] + i] = data[i + 1];
 	}

 	ret = i2c_master_send(client, data, length);
 	if (ret < 0) {
 		printk(KERN_ERR "SAA7191: saa7191_write_block(): "
 		       "write failed\n");
 		return ret;
 	}

 	return 0;
 }

 /* Helper functions */

 static int saa7191_s_routing(struct v4l2_subdev *sd,
 			     u32 input, u32 output, u32 config)
 {
 	struct saa7191 *decoder = to_saa7191(sd);
 	u8 luma = saa7191_read_reg(sd, SAA7191_REG_LUMA);
 	u8 iock = saa7191_read_reg(sd, SAA7191_REG_IOCK);
 	int err;

 	switch (input) {
 	case SAA7191_INPUT_COMPOSITE: /* Set Composite input */
 		iock &= ~(SAA7191_IOCK_CHRS | SAA7191_IOCK_GPSW1
 			  | SAA7191_IOCK_GPSW2);
 		/* Chrominance trap active */
 		luma &= ~SAA7191_LUMA_BYPS;
 		break;
 	case SAA7191_INPUT_SVIDEO: /* Set S-Video input */
 		iock |= SAA7191_IOCK_CHRS | SAA7191_IOCK_GPSW2;
 		/* Chrominance trap bypassed */
 		luma |= SAA7191_LUMA_BYPS;
 		break;
 	default:
 		return -EINVAL;
 	}

 	err = saa7191_write_reg(sd, SAA7191_REG_LUMA, luma);
 	if (err)
 		return -EIO;
 	err = saa7191_write_reg(sd, SAA7191_REG_IOCK, iock);
 	if (err)
 		return -EIO;

 	decoder->input = input;

 	return 0;
 }

 static int saa7191_s_std(struct v4l2_subdev *sd, v4l2_std_id norm)
 {
 	struct saa7191 *decoder = to_saa7191(sd);
 	u8 stdc = saa7191_read_reg(sd, SAA7191_REG_STDC);
 	u8 ctl3 = saa7191_read_reg(sd, SAA7191_REG_CTL3);
 	u8 chcv = saa7191_read_reg(sd, SAA7191_REG_CHCV);
 	int err;

 	if (norm & V4L2_STD_PAL) {
 		stdc &= ~SAA7191_STDC_SECS;
 		ctl3 &= ~(SAA7191_CTL3_AUFD | SAA7191_CTL3_FSEL);
 		chcv = SAA7191_CHCV_PAL;
 	} else if (norm & V4L2_STD_NTSC) {
 		stdc &= ~SAA7191_STDC_SECS;
 		ctl3 &= ~SAA7191_CTL3_AUFD;
 		ctl3 |= SAA7191_CTL3_FSEL;
 		chcv = SAA7191_CHCV_NTSC;
 	} else if (norm & V4L2_STD_SECAM) {
 		stdc |= SAA7191_STDC_SECS;
 		ctl3 &= ~(SAA7191_CTL3_AUFD | SAA7191_CTL3_FSEL);
 		chcv = SAA7191_CHCV_PAL;
 	} else {
 		return -EINVAL;
 	}

 	err = saa7191_write_reg(sd, SAA7191_REG_CTL3, ctl3);
 	if (err)
 		return -EIO;
 	err = saa7191_write_reg(sd, SAA7191_REG_STDC, stdc);
 	if (err)
 		return -EIO;
 	err = saa7191_write_reg(sd, SAA7191_REG_CHCV, chcv);
 	if (err)
 		return -EIO;

 	decoder->norm = norm;

 	dprintk("ctl3: %02x stdc: %02x chcv: %02x\n", ctl3,
 		stdc, chcv);
 	dprintk("norm: %llx\n", norm);

 	return 0;
 }

 static int saa7191_wait_for_signal(struct v4l2_subdev *sd, u8 *status)
 {
 	int i = 0;

 	dprintk("Checking for signal...\n");

 	for (i = 0; i < SAA7191_SYNC_COUNT; i++) {
 		if (saa7191_read_status(sd, status))
 			return -EIO;

 		if (((*status) & SAA7191_STATUS_HLCK) == 0) {
 			dprintk("Signal found\n");
 			return 0;
 		}

 		msleep(SAA7191_SYNC_DELAY);
 	}

 	dprintk("No signal\n");

 	return -EBUSY;
 }

 static int saa7191_querystd(struct v4l2_subdev *sd, v4l2_std_id *norm)
 {
 	struct saa7191 *decoder = to_saa7191(sd);
 	u8 stdc = saa7191_read_reg(sd, SAA7191_REG_STDC);
 	u8 ctl3 = saa7191_read_reg(sd, SAA7191_REG_CTL3);
 	u8 status;
 	v4l2_std_id old_norm = decoder->norm;
 	int err = 0;

 	dprintk("SAA7191 extended signal auto-detection...\n");

 	*norm &= V4L2_STD_NTSC | V4L2_STD_PAL | V4L2_STD_SECAM;
 	stdc &= ~SAA7191_STDC_SECS;
 	ctl3 &= ~(SAA7191_CTL3_FSEL);

 	err = saa7191_write_reg(sd, SAA7191_REG_STDC, stdc);
 	if (err) {
 		err = -EIO;
 		goto out;
 	}
 	err = saa7191_write_reg(sd, SAA7191_REG_CTL3, ctl3);
 	if (err) {
 		err = -EIO;
 		goto out;
 	}

 	ctl3 |= SAA7191_CTL3_AUFD;
 	err = saa7191_write_reg(sd, SAA7191_REG_CTL3, ctl3);
 	if (err) {
 		err = -EIO;
 		goto out;
 	}

 	msleep(SAA7191_SYNC_DELAY);

 	err = saa7191_wait_for_signal(sd, &status);
 	if (err)
 		goto out;

 	if (status & SAA7191_STATUS_FIDT) {
 		/* 60Hz signal -> NTSC */
 		dprintk("60Hz signal: NTSC\n");
 		*norm &= V4L2_STD_NTSC;
 		return 0;
 	}

 	/* 50Hz signal */
 	dprintk("50Hz signal: Trying PAL...\n");

 	/* try PAL first */
 	err = saa7191_s_std(sd, V4L2_STD_PAL);
 	if (err)
 		goto out;

 	msleep(SAA7191_SYNC_DELAY);

 	err = saa7191_wait_for_signal(sd, &status);
 	if (err)
 		goto out;

 	/* not 50Hz ? */
 	if (status & SAA7191_STATUS_FIDT) {
 		dprintk("No 50Hz signal\n");
 		saa7191_s_std(sd, old_norm);
 		*norm = V4L2_STD_UNKNOWN;
 		return 0;
 	}

 	if (status & SAA7191_STATUS_CODE) {
 		dprintk("PAL\n");
 		*norm &= V4L2_STD_PAL;
 		return saa7191_s_std(sd, old_norm);
 	}

 	dprintk("No color detected with PAL - Trying SECAM...\n");

 	/* no color detected ? -> try SECAM */
 	err = saa7191_s_std(sd, V4L2_STD_SECAM);
 	if (err)
 		goto out;

 	msleep(SAA7191_SYNC_DELAY);

 	err = saa7191_wait_for_signal(sd, &status);
 	if (err)
 		goto out;

 	/* not 50Hz ? */
 	if (status & SAA7191_STATUS_FIDT) {
 		dprintk("No 50Hz signal\n");
 		*norm = V4L2_STD_UNKNOWN;
 		goto out;
 	}

 	if (status & SAA7191_STATUS_CODE) {
 		/* Color detected -> SECAM */
 		dprintk("SECAM\n");
 		*norm &= V4L2_STD_SECAM;
 		return saa7191_s_std(sd, old_norm);
 	}

 	dprintk("No color detected with SECAM - Going back to PAL.\n");
 	*norm = V4L2_STD_UNKNOWN;

 out:
 	return saa7191_s_std(sd, old_norm);
 }

 static int saa7191_autodetect_norm(struct v4l2_subdev *sd)
 {
 	u8 status;

 	dprintk("SAA7191 signal auto-detection...\n");

 	dprintk("Reading status...\n");

 	if (saa7191_read_status(sd, &status))
 		return -EIO;

 	dprintk("Checking for signal...\n");

 	/* no signal ? */
 	if (status & SAA7191_STATUS_HLCK) {
 		dprintk("No signal\n");
 		return -EBUSY;
 	}

 	dprintk("Signal found\n");

 	if (status & SAA7191_STATUS_FIDT) {
 		/* 60hz signal -> NTSC */
 		dprintk("NTSC\n");
 		return saa7191_s_std(sd, V4L2_STD_NTSC);
 	} else {
 		/* 50hz signal -> PAL */
 		dprintk("PAL\n");
 		return saa7191_s_std(sd, V4L2_STD_PAL);
 	}
 }

 static int saa7191_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
 {
 	u8 reg;
 	int ret = 0;

 	switch (ctrl->id) {
 	case SAA7191_CONTROL_BANDPASS:
 	case SAA7191_CONTROL_BANDPASS_WEIGHT:
 	case SAA7191_CONTROL_CORING:
 		reg = saa7191_read_reg(sd, SAA7191_REG_LUMA);
 		switch (ctrl->id) {
 		case SAA7191_CONTROL_BANDPASS:
 			ctrl->value = ((s32)reg & SAA7191_LUMA_BPSS_MASK)
 				>> SAA7191_LUMA_BPSS_SHIFT;
 			break;
 		case SAA7191_CONTROL_BANDPASS_WEIGHT:
 			ctrl->value = ((s32)reg & SAA7191_LUMA_APER_MASK)
 				>> SAA7191_LUMA_APER_SHIFT;
 			break;
 		case SAA7191_CONTROL_CORING:
 			ctrl->value = ((s32)reg & SAA7191_LUMA_CORI_MASK)
 				>> SAA7191_LUMA_CORI_SHIFT;
 			break;
 		}
 		break;
 	case SAA7191_CONTROL_FORCE_COLOUR:
 	case SAA7191_CONTROL_CHROMA_GAIN:
 		reg = saa7191_read_reg(sd, SAA7191_REG_GAIN);
 		if (ctrl->id == SAA7191_CONTROL_FORCE_COLOUR)
 			ctrl->value = ((s32)reg & SAA7191_GAIN_COLO) ? 1 : 0;
 		else
 			ctrl->value = ((s32)reg & SAA7191_GAIN_LFIS_MASK)
 				>> SAA7191_GAIN_LFIS_SHIFT;
 		break;
 	case V4L2_CID_HUE:
 		reg = saa7191_read_reg(sd, SAA7191_REG_HUEC);
 		if (reg < 0x80)
 			reg += 0x80;
 		else
 			reg -= 0x80;
 		ctrl->value = (s32)reg;
 		break;
 	case SAA7191_CONTROL_VTRC:
 		reg = saa7191_read_reg(sd, SAA7191_REG_STDC);
 		ctrl->value = ((s32)reg & SAA7191_STDC_VTRC) ? 1 : 0;
 		break;
 	case SAA7191_CONTROL_LUMA_DELAY:
 		reg = saa7191_read_reg(sd, SAA7191_REG_CTL3);
 		ctrl->value = ((s32)reg & SAA7191_CTL3_YDEL_MASK)
 			>> SAA7191_CTL3_YDEL_SHIFT;
 		if (ctrl->value >= 4)
 			ctrl->value -= 8;
 		break;
 	case SAA7191_CONTROL_VNR:
 		reg = saa7191_read_reg(sd, SAA7191_REG_CTL4);
 		ctrl->value = ((s32)reg & SAA7191_CTL4_VNOI_MASK)
 			>> SAA7191_CTL4_VNOI_SHIFT;
 		break;
 	default:
 		ret = -EINVAL;
 	}

 	return ret;
 }

 static int saa7191_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
 {
 	u8 reg;
 	int ret = 0;

 	switch (ctrl->id) {
 	case SAA7191_CONTROL_BANDPASS:
 	case SAA7191_CONTROL_BANDPASS_WEIGHT:
 	case SAA7191_CONTROL_CORING:
 		reg = saa7191_read_reg(sd, SAA7191_REG_LUMA);
 		switch (ctrl->id) {
 		case SAA7191_CONTROL_BANDPASS:
 			reg &= ~SAA7191_LUMA_BPSS_MASK;
 			reg |= (ctrl->value << SAA7191_LUMA_BPSS_SHIFT)
 				& SAA7191_LUMA_BPSS_MASK;
 			break;
 		case SAA7191_CONTROL_BANDPASS_WEIGHT:
 			reg &= ~SAA7191_LUMA_APER_MASK;
 			reg |= (ctrl->value << SAA7191_LUMA_APER_SHIFT)
 				& SAA7191_LUMA_APER_MASK;
 			break;
 		case SAA7191_CONTROL_CORING:
 			reg &= ~SAA7191_LUMA_CORI_MASK;
 			reg |= (ctrl->value << SAA7191_LUMA_CORI_SHIFT)
 				& SAA7191_LUMA_CORI_MASK;
 			break;
 		}
 		ret = saa7191_write_reg(sd, SAA7191_REG_LUMA, reg);
 		break;
 	case SAA7191_CONTROL_FORCE_COLOUR:
 	case SAA7191_CONTROL_CHROMA_GAIN:
 		reg = saa7191_read_reg(sd, SAA7191_REG_GAIN);
 		if (ctrl->id == SAA7191_CONTROL_FORCE_COLOUR) {
 			if (ctrl->value)
 				reg |= SAA7191_GAIN_COLO;
 			else
 				reg &= ~SAA7191_GAIN_COLO;
 		} else {
 			reg &= ~SAA7191_GAIN_LFIS_MASK;
 			reg |= (ctrl->value << SAA7191_GAIN_LFIS_SHIFT)
 				& SAA7191_GAIN_LFIS_MASK;
 		}
 		ret = saa7191_write_reg(sd, SAA7191_REG_GAIN, reg);
 		break;
 	case V4L2_CID_HUE:
 		reg = ctrl->value & 0xff;
 		if (reg < 0x80)
 			reg += 0x80;
 		else
 			reg -= 0x80;
 		ret = saa7191_write_reg(sd, SAA7191_REG_HUEC, reg);
 		break;
 	case SAA7191_CONTROL_VTRC:
 		reg = saa7191_read_reg(sd, SAA7191_REG_STDC);
 		if (ctrl->value)
 			reg |= SAA7191_STDC_VTRC;
 		else
 			reg &= ~SAA7191_STDC_VTRC;
 		ret = saa7191_write_reg(sd, SAA7191_REG_STDC, reg);
 		break;
 	case SAA7191_CONTROL_LUMA_DELAY: {
 		s32 value = ctrl->value;
 		if (value < 0)
 			value += 8;
 		reg = saa7191_read_reg(sd, SAA7191_REG_CTL3);
 		reg &= ~SAA7191_CTL3_YDEL_MASK;
 		reg |= (value << SAA7191_CTL3_YDEL_SHIFT)
 			& SAA7191_CTL3_YDEL_MASK;
 		ret = saa7191_write_reg(sd, SAA7191_REG_CTL3, reg);
 		break;
 	}
 	case SAA7191_CONTROL_VNR:
 		reg = saa7191_read_reg(sd, SAA7191_REG_CTL4);
 		reg &= ~SAA7191_CTL4_VNOI_MASK;
 		reg |= (ctrl->value << SAA7191_CTL4_VNOI_SHIFT)
 			& SAA7191_CTL4_VNOI_MASK;
 		ret = saa7191_write_reg(sd, SAA7191_REG_CTL4, reg);
 		break;
 	default:
 		ret = -EINVAL;
 	}

 	return ret;
 }

 /* I2C-interface */

 static int saa7191_g_input_status(struct v4l2_subdev *sd, u32 *status)
 {
 	u8 status_reg;
 	int res = V4L2_IN_ST_NO_SIGNAL;

 	if (saa7191_read_status(sd, &status_reg))
 		return -EIO;
 	if ((status_reg & SAA7191_STATUS_HLCK) == 0)
 		res = 0;
 	if (!(status_reg & SAA7191_STATUS_CODE))
 		res |= V4L2_IN_ST_NO_COLOR;
 	*status = res;
 	return 0;
 }


 /* ----------------------------------------------------------------------- */

 static const struct v4l2_subdev_core_ops saa7191_core_ops = {
 	.g_ctrl = saa7191_g_ctrl,
 	.s_ctrl = saa7191_s_ctrl,
 	.s_std = saa7191_s_std,
 };

 static const struct v4l2_subdev_video_ops saa7191_video_ops = {
 	.s_routing = saa7191_s_routing,
 	.querystd = saa7191_querystd,
 	.g_input_status = saa7191_g_input_status,
 };

 static const struct v4l2_subdev_ops saa7191_ops = {
 	.core = &saa7191_core_ops,
 	.video = &saa7191_video_ops,
 };

 static int saa7191_probe(struct i2c_client *client,
 			  const struct i2c_device_id *id)
 {
 	int err = 0;
 	struct saa7191 *decoder;
 	struct v4l2_subdev *sd;

 	v4l_info(client, "chip found @ 0x%x (%s)\n",
 			client->addr << 1, client->adapter->name);

 	decoder = devm_kzalloc(&client->dev, sizeof(*decoder), GFP_KERNEL);
 	if (!decoder)
 		return -ENOMEM;

 	sd = &decoder->sd;
 	v4l2_i2c_subdev_init(sd, client, &saa7191_ops);

 	err = saa7191_write_block(sd, sizeof(initseq), initseq);
 	if (err) {
 		printk(KERN_ERR "SAA7191 initialization failed\n");
 		return err;
 	}

 	printk(KERN_INFO "SAA7191 initialized\n");

 	decoder->input = SAA7191_INPUT_COMPOSITE;
 	decoder->norm = V4L2_STD_PAL;

 	err = saa7191_autodetect_norm(sd);
 	if (err && (err != -EBUSY))
 		printk(KERN_ERR "SAA7191: Signal auto-detection failed\n");

 	return 0;
 }

 static int saa7191_remove(struct i2c_client *client)
 {
 	struct v4l2_subdev *sd = i2c_get_clientdata(client);

 	v4l2_device_unregister_subdev(sd);
 	return 0;
 }

 static const struct i2c_device_id saa7191_id[] = {
 	{ "saa7191", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, saa7191_id);

 static struct i2c_driver saa7191_driver = {
 	.driver = {
 		.owner	= THIS_MODULE,
 		.name	= "saa7191",
 	},
 	.probe		= saa7191_probe,
 	.remove		= saa7191_remove,
 	.id_table	= saa7191_id,
 };

 module_i2c_driver(saa7191_driver);
	/*
	* saa7191.c - Philips SAA7191 video decoder driver
	*
	* Copyright (C) 2003 Ladislav Michl <ladis@linux-mips.org>
	* Copyright (C) 2004,2005 Mikael Nousiainen <tmnousia@cc.hut.fi>
	*
	* 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.
	*/

	#include <linux/delay.h>
	#include <linux/errno.h>
	#include <linux/fs.h>
	#include <linux/init.h>
	#include <linux/kernel.h>
	#include <linux/major.h>
	#include <linux/module.h>
	#include <linux/mm.h>
	#include <linux/slab.h>

	#include <linux/videodev2.h>
	#include <linux/i2c.h>
	#include <media/v4l2-device.h>

	#include "saa7191.h"

	#define SAA7191_MODULE_VERSION "0.0.5"

	MODULE_DESCRIPTION("Philips SAA7191 video decoder driver");
	MODULE_VERSION(SAA7191_MODULE_VERSION);
	MODULE_AUTHOR("Mikael Nousiainen <tmnousia@cc.hut.fi>");
	MODULE_LICENSE("GPL");


	// #define SAA7191_DEBUG

	#ifdef SAA7191_DEBUG
	#define dprintk(x...) printk("SAA7191: " x);
	#else
	#define dprintk(x...)
	#endif

	#define SAA7191_SYNC_COUNT 30
	#define SAA7191_SYNC_DELAY 100 /* milliseconds */

	struct saa7191 {
	struct v4l2_subdev sd;

	/* the register values are stored here as the actual
	* I2C-registers are write-only */
	u8 reg[25];

	int input;
	v4l2_std_id norm;
	};

	static inline struct saa7191 to_saa7191(struct v4l2_subdev sd)
	{
	return container_of(sd, struct saa7191, sd);
	}

	static const u8 initseq[] = {
	0, /* Subaddress */

	0x50, /* (0x50) SAA7191_REG_IDEL */

	/* 50 Hz signal timing */
	0x30, /* (0x30) SAA7191_REG_HSYB */
	0x00, /* (0x00) SAA7191_REG_HSYS */
	0xe8, /* (0xe8) SAA7191_REG_HCLB */
	0xb6, /* (0xb6) SAA7191_REG_HCLS */
	0xf4, /* (0xf4) SAA7191_REG_HPHI */

	/* control */
	SAA7191_LUMA_APER_1, /* (0x01) SAA7191_REG_LUMA - CVBS mode */
	0x00, /* (0x00) SAA7191_REG_HUEC */
	0xf8, /* (0xf8) SAA7191_REG_CKTQ */
	0xf8, /* (0xf8) SAA7191_REG_CKTS */
	0x90, /* (0x90) SAA7191_REG_PLSE */
	0x90, /* (0x90) SAA7191_REG_SESE */
	0x00, /* (0x00) SAA7191_REG_GAIN */
	SAA7191_STDC_NFEN \| SAA7191_STDC_HRMV, /* (0x0c) SAA7191_REG_STDC
	* - not SECAM,
	* slow time constant */
	SAA7191_IOCK_OEDC \| SAA7191_IOCK_OEHS \| SAA7191_IOCK_OEVS
	\| SAA7191_IOCK_OEDY, /* (0x78) SAA7191_REG_IOCK
	* - chroma from CVBS, GPSW1 & 2 off */
	SAA7191_CTL3_AUFD \| SAA7191_CTL3_SCEN \| SAA7191_CTL3_OFTS
	\| SAA7191_CTL3_YDEL0, /* (0x99) SAA7191_REG_CTL3
	* - automatic field detection */
	0x00, /* (0x00) SAA7191_REG_CTL4 */
	0x2c, /* (0x2c) SAA7191_REG_CHCV - PAL nominal value */
	0x00, /* unused */
	0x00, /* unused */

	/* 60 Hz signal timing */
	0x34, /* (0x34) SAA7191_REG_HS6B */
	0x0a, /* (0x0a) SAA7191_REG_HS6S */
	0xf4, /* (0xf4) SAA7191_REG_HC6B */
	0xce, /* (0xce) SAA7191_REG_HC6S */
	0xf4, /* (0xf4) SAA7191_REG_HP6I */
	};

	/* SAA7191 register handling */

	static u8 saa7191_read_reg(struct v4l2_subdev *sd, u8 reg)
	{
	return to_saa7191(sd)->reg[reg];
	}

	static int saa7191_read_status(struct v4l2_subdev sd, u8 value)
	{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	int ret;

	ret = i2c_master_recv(client, value, 1);
	if (ret < 0) {
	printk(KERN_ERR "SAA7191: saa7191_read_status(): read failed\n");
	return ret;
	}

	return 0;
	}


	static int saa7191_write_reg(struct v4l2_subdev *sd, u8 reg, u8 value)
	{
	struct i2c_client *client = v4l2_get_subdevdata(sd);

	to_saa7191(sd)->reg[reg] = value;
	return i2c_smbus_write_byte_data(client, reg, value);
	}

	/* the first byte of data must be the first subaddress number (register) */
	static int saa7191_write_block(struct v4l2_subdev *sd,
	u8 length, const u8 *data)
	{
	struct i2c_client *client = v4l2_get_subdevdata(sd);
	struct saa7191 *decoder = to_saa7191(sd);
	int i;
	int ret;

	for (i = 0; i < (length - 1); i++) {
	decoder->reg[data[0] + i] = data[i + 1];
	}

	ret = i2c_master_send(client, data, length);
	if (ret < 0) {
	printk(KERN_ERR "SAA7191: saa7191_write_block(): "
	"write failed\n");
	return ret;
	}

	return 0;
	}

	/* Helper functions */

	static int saa7191_s_routing(struct v4l2_subdev *sd,
	u32 input, u32 output, u32 config)
	{
	struct saa7191 *decoder = to_saa7191(sd);
	u8 luma = saa7191_read_reg(sd, SAA7191_REG_LUMA);
	u8 iock = saa7191_read_reg(sd, SAA7191_REG_IOCK);
	int err;

	switch (input) {
	case SAA7191_INPUT_COMPOSITE: /* Set Composite input */
	iock &= ~(SAA7191_IOCK_CHRS \| SAA7191_IOCK_GPSW1
	\| SAA7191_IOCK_GPSW2);
	/* Chrominance trap active */
	luma &= ~SAA7191_LUMA_BYPS;
	break;
	case SAA7191_INPUT_SVIDEO: /* Set S-Video input */
	iock \|= SAA7191_IOCK_CHRS \| SAA7191_IOCK_GPSW2;
	/* Chrominance trap bypassed */
	luma \|= SAA7191_LUMA_BYPS;
	break;
	default:
	return -EINVAL;
	}

	err = saa7191_write_reg(sd, SAA7191_REG_LUMA, luma);
	if (err)
	return -EIO;
	err = saa7191_write_reg(sd, SAA7191_REG_IOCK, iock);
	if (err)
	return -EIO;

	decoder->input = input;

	return 0;
	}

	static int saa7191_s_std(struct v4l2_subdev *sd, v4l2_std_id norm)
	{
	struct saa7191 *decoder = to_saa7191(sd);
	u8 stdc = saa7191_read_reg(sd, SAA7191_REG_STDC);
	u8 ctl3 = saa7191_read_reg(sd, SAA7191_REG_CTL3);
	u8 chcv = saa7191_read_reg(sd, SAA7191_REG_CHCV);
	int err;

	if (norm & V4L2_STD_PAL) {
	stdc &= ~SAA7191_STDC_SECS;
	ctl3 &= ~(SAA7191_CTL3_AUFD \| SAA7191_CTL3_FSEL);
	chcv = SAA7191_CHCV_PAL;
	} else if (norm & V4L2_STD_NTSC) {
	stdc &= ~SAA7191_STDC_SECS;
	ctl3 &= ~SAA7191_CTL3_AUFD;
	ctl3 \|= SAA7191_CTL3_FSEL;
	chcv = SAA7191_CHCV_NTSC;
	} else if (norm & V4L2_STD_SECAM) {
	stdc \|= SAA7191_STDC_SECS;
	ctl3 &= ~(SAA7191_CTL3_AUFD \| SAA7191_CTL3_FSEL);
	chcv = SAA7191_CHCV_PAL;
	} else {
	return -EINVAL;
	}

	err = saa7191_write_reg(sd, SAA7191_REG_CTL3, ctl3);
	if (err)
	return -EIO;
	err = saa7191_write_reg(sd, SAA7191_REG_STDC, stdc);
	if (err)
	return -EIO;
	err = saa7191_write_reg(sd, SAA7191_REG_CHCV, chcv);
	if (err)
	return -EIO;

	decoder->norm = norm;

	dprintk("ctl3: %02x stdc: %02x chcv: %02x\n", ctl3,
	stdc, chcv);
	dprintk("norm: %llx\n", norm);

	return 0;
	}

	static int saa7191_wait_for_signal(struct v4l2_subdev sd, u8 status)
	{
	int i = 0;

	dprintk("Checking for signal...\n");

	for (i = 0; i < SAA7191_SYNC_COUNT; i++) {
	if (saa7191_read_status(sd, status))
	return -EIO;

	if (((*status) & SAA7191_STATUS_HLCK) == 0) {
	dprintk("Signal found\n");
	return 0;
	}

	msleep(SAA7191_SYNC_DELAY);
	}

	dprintk("No signal\n");

	return -EBUSY;
	}

	static int saa7191_querystd(struct v4l2_subdev sd, v4l2_std_id norm)
	{
	struct saa7191 *decoder = to_saa7191(sd);
	u8 stdc = saa7191_read_reg(sd, SAA7191_REG_STDC);
	u8 ctl3 = saa7191_read_reg(sd, SAA7191_REG_CTL3);
	u8 status;
	v4l2_std_id old_norm = decoder->norm;
	int err = 0;

	dprintk("SAA7191 extended signal auto-detection...\n");

	*norm &= V4L2_STD_NTSC \| V4L2_STD_PAL \| V4L2_STD_SECAM;
	stdc &= ~SAA7191_STDC_SECS;
	ctl3 &= ~(SAA7191_CTL3_FSEL);

	err = saa7191_write_reg(sd, SAA7191_REG_STDC, stdc);
	if (err) {
	err = -EIO;
	goto out;
	}
	err = saa7191_write_reg(sd, SAA7191_REG_CTL3, ctl3);
	if (err) {
	err = -EIO;
	goto out;
	}

	ctl3 \|= SAA7191_CTL3_AUFD;
	err = saa7191_write_reg(sd, SAA7191_REG_CTL3, ctl3);
	if (err) {
	err = -EIO;
	goto out;
	}

	msleep(SAA7191_SYNC_DELAY);

	err = saa7191_wait_for_signal(sd, &status);
	if (err)
	goto out;

	if (status & SAA7191_STATUS_FIDT) {
	/* 60Hz signal -> NTSC */
	dprintk("60Hz signal: NTSC\n");
	*norm &= V4L2_STD_NTSC;
	return 0;
	}

	/* 50Hz signal */
	dprintk("50Hz signal: Trying PAL...\n");

	/* try PAL first */
	err = saa7191_s_std(sd, V4L2_STD_PAL);
	if (err)
	goto out;

	msleep(SAA7191_SYNC_DELAY);

	err = saa7191_wait_for_signal(sd, &status);
	if (err)
	goto out;

	/* not 50Hz ? */
	if (status & SAA7191_STATUS_FIDT) {
	dprintk("No 50Hz signal\n");
	saa7191_s_std(sd, old_norm);
	*norm = V4L2_STD_UNKNOWN;
	return 0;
	}

	if (status & SAA7191_STATUS_CODE) {
	dprintk("PAL\n");
	*norm &= V4L2_STD_PAL;
	return saa7191_s_std(sd, old_norm);
	}

	dprintk("No color detected with PAL - Trying SECAM...\n");

	/* no color detected ? -> try SECAM */
	err = saa7191_s_std(sd, V4L2_STD_SECAM);
	if (err)
	goto out;

	msleep(SAA7191_SYNC_DELAY);

	err = saa7191_wait_for_signal(sd, &status);
	if (err)
	goto out;

	/* not 50Hz ? */
	if (status & SAA7191_STATUS_FIDT) {
	dprintk("No 50Hz signal\n");
	*norm = V4L2_STD_UNKNOWN;
	goto out;
	}

	if (status & SAA7191_STATUS_CODE) {
	/* Color detected -> SECAM */
	dprintk("SECAM\n");
	*norm &= V4L2_STD_SECAM;
	return saa7191_s_std(sd, old_norm);
	}

	dprintk("No color detected with SECAM - Going back to PAL.\n");
	*norm = V4L2_STD_UNKNOWN;

	out:
	return saa7191_s_std(sd, old_norm);
	}

	static int saa7191_autodetect_norm(struct v4l2_subdev *sd)
	{
	u8 status;

	dprintk("SAA7191 signal auto-detection...\n");

	dprintk("Reading status...\n");

	if (saa7191_read_status(sd, &status))
	return -EIO;

	dprintk("Checking for signal...\n");

	/* no signal ? */
	if (status & SAA7191_STATUS_HLCK) {
	dprintk("No signal\n");
	return -EBUSY;
	}

	dprintk("Signal found\n");

	if (status & SAA7191_STATUS_FIDT) {
	/* 60hz signal -> NTSC */
	dprintk("NTSC\n");
	return saa7191_s_std(sd, V4L2_STD_NTSC);
	} else {
	/* 50hz signal -> PAL */
	dprintk("PAL\n");
	return saa7191_s_std(sd, V4L2_STD_PAL);
	}
	}

	static int saa7191_g_ctrl(struct v4l2_subdev sd, struct v4l2_control ctrl)
	{
	u8 reg;
	int ret = 0;

	switch (ctrl->id) {
	case SAA7191_CONTROL_BANDPASS:
	case SAA7191_CONTROL_BANDPASS_WEIGHT:
	case SAA7191_CONTROL_CORING:
	reg = saa7191_read_reg(sd, SAA7191_REG_LUMA);
	switch (ctrl->id) {
	case SAA7191_CONTROL_BANDPASS:
	ctrl->value = ((s32)reg & SAA7191_LUMA_BPSS_MASK)
	>> SAA7191_LUMA_BPSS_SHIFT;
	break;
	case SAA7191_CONTROL_BANDPASS_WEIGHT:
	ctrl->value = ((s32)reg & SAA7191_LUMA_APER_MASK)
	>> SAA7191_LUMA_APER_SHIFT;
	break;
	case SAA7191_CONTROL_CORING:
	ctrl->value = ((s32)reg & SAA7191_LUMA_CORI_MASK)
	>> SAA7191_LUMA_CORI_SHIFT;
	break;
	}
	break;
	case SAA7191_CONTROL_FORCE_COLOUR:
	case SAA7191_CONTROL_CHROMA_GAIN:
	reg = saa7191_read_reg(sd, SAA7191_REG_GAIN);
	if (ctrl->id == SAA7191_CONTROL_FORCE_COLOUR)
	ctrl->value = ((s32)reg & SAA7191_GAIN_COLO) ? 1 : 0;
	else
	ctrl->value = ((s32)reg & SAA7191_GAIN_LFIS_MASK)
	>> SAA7191_GAIN_LFIS_SHIFT;
	break;
	case V4L2_CID_HUE:
	reg = saa7191_read_reg(sd, SAA7191_REG_HUEC);
	if (reg < 0x80)
	reg += 0x80;
	else
	reg -= 0x80;
	ctrl->value = (s32)reg;
	break;
	case SAA7191_CONTROL_VTRC:
	reg = saa7191_read_reg(sd, SAA7191_REG_STDC);
	ctrl->value = ((s32)reg & SAA7191_STDC_VTRC) ? 1 : 0;
	break;
	case SAA7191_CONTROL_LUMA_DELAY:
	reg = saa7191_read_reg(sd, SAA7191_REG_CTL3);
	ctrl->value = ((s32)reg & SAA7191_CTL3_YDEL_MASK)
	>> SAA7191_CTL3_YDEL_SHIFT;
	if (ctrl->value >= 4)
	ctrl->value -= 8;
	break;
	case SAA7191_CONTROL_VNR:
	reg = saa7191_read_reg(sd, SAA7191_REG_CTL4);
	ctrl->value = ((s32)reg & SAA7191_CTL4_VNOI_MASK)
	>> SAA7191_CTL4_VNOI_SHIFT;
	break;
	default:
	ret = -EINVAL;
	}

	return ret;
	}

	static int saa7191_s_ctrl(struct v4l2_subdev sd, struct v4l2_control ctrl)
	{
	u8 reg;
	int ret = 0;

	switch (ctrl->id) {
	case SAA7191_CONTROL_BANDPASS:
	case SAA7191_CONTROL_BANDPASS_WEIGHT:
	case SAA7191_CONTROL_CORING:
	reg = saa7191_read_reg(sd, SAA7191_REG_LUMA);
	switch (ctrl->id) {
	case SAA7191_CONTROL_BANDPASS:
	reg &= ~SAA7191_LUMA_BPSS_MASK;
	reg \|= (ctrl->value << SAA7191_LUMA_BPSS_SHIFT)
	& SAA7191_LUMA_BPSS_MASK;
	break;
	case SAA7191_CONTROL_BANDPASS_WEIGHT:
	reg &= ~SAA7191_LUMA_APER_MASK;
	reg \|= (ctrl->value << SAA7191_LUMA_APER_SHIFT)
	& SAA7191_LUMA_APER_MASK;
	break;
	case SAA7191_CONTROL_CORING:
	reg &= ~SAA7191_LUMA_CORI_MASK;
	reg \|= (ctrl->value << SAA7191_LUMA_CORI_SHIFT)
	& SAA7191_LUMA_CORI_MASK;
	break;
	}
	ret = saa7191_write_reg(sd, SAA7191_REG_LUMA, reg);
	break;
	case SAA7191_CONTROL_FORCE_COLOUR:
	case SAA7191_CONTROL_CHROMA_GAIN:
	reg = saa7191_read_reg(sd, SAA7191_REG_GAIN);
	if (ctrl->id == SAA7191_CONTROL_FORCE_COLOUR) {
	if (ctrl->value)
	reg \|= SAA7191_GAIN_COLO;
	else
	reg &= ~SAA7191_GAIN_COLO;
	} else {
	reg &= ~SAA7191_GAIN_LFIS_MASK;
	reg \|= (ctrl->value << SAA7191_GAIN_LFIS_SHIFT)
	& SAA7191_GAIN_LFIS_MASK;
	}
	ret = saa7191_write_reg(sd, SAA7191_REG_GAIN, reg);
	break;
	case V4L2_CID_HUE:
	reg = ctrl->value & 0xff;
	if (reg < 0x80)
	reg += 0x80;
	else
	reg -= 0x80;
	ret = saa7191_write_reg(sd, SAA7191_REG_HUEC, reg);
	break;
	case SAA7191_CONTROL_VTRC:
	reg = saa7191_read_reg(sd, SAA7191_REG_STDC);
	if (ctrl->value)
	reg \|= SAA7191_STDC_VTRC;
	else
	reg &= ~SAA7191_STDC_VTRC;
	ret = saa7191_write_reg(sd, SAA7191_REG_STDC, reg);
	break;
	case SAA7191_CONTROL_LUMA_DELAY: {
	s32 value = ctrl->value;
	if (value < 0)
	value += 8;
	reg = saa7191_read_reg(sd, SAA7191_REG_CTL3);
	reg &= ~SAA7191_CTL3_YDEL_MASK;
	reg \|= (value << SAA7191_CTL3_YDEL_SHIFT)
	& SAA7191_CTL3_YDEL_MASK;
	ret = saa7191_write_reg(sd, SAA7191_REG_CTL3, reg);
	break;
	}
	case SAA7191_CONTROL_VNR:
	reg = saa7191_read_reg(sd, SAA7191_REG_CTL4);
	reg &= ~SAA7191_CTL4_VNOI_MASK;
	reg \|= (ctrl->value << SAA7191_CTL4_VNOI_SHIFT)
	& SAA7191_CTL4_VNOI_MASK;
	ret = saa7191_write_reg(sd, SAA7191_REG_CTL4, reg);
	break;
	default:
	ret = -EINVAL;
	}

	return ret;
	}

	/* I2C-interface */

	static int saa7191_g_input_status(struct v4l2_subdev sd, u32 status)
	{
	u8 status_reg;
	int res = V4L2_IN_ST_NO_SIGNAL;

	if (saa7191_read_status(sd, &status_reg))
	return -EIO;
	if ((status_reg & SAA7191_STATUS_HLCK) == 0)
	res = 0;
	if (!(status_reg & SAA7191_STATUS_CODE))
	res \|= V4L2_IN_ST_NO_COLOR;
	*status = res;
	return 0;
	}


	/* ----------------------------------------------------------------------- */

	static const struct v4l2_subdev_core_ops saa7191_core_ops = {
	.g_ctrl = saa7191_g_ctrl,
	.s_ctrl = saa7191_s_ctrl,
	.s_std = saa7191_s_std,
	};

	static const struct v4l2_subdev_video_ops saa7191_video_ops = {
	.s_routing = saa7191_s_routing,
	.querystd = saa7191_querystd,
	.g_input_status = saa7191_g_input_status,
	};

	static const struct v4l2_subdev_ops saa7191_ops = {
	.core = &saa7191_core_ops,
	.video = &saa7191_video_ops,
	};

	static int saa7191_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
	{
	int err = 0;
	struct saa7191 *decoder;
	struct v4l2_subdev *sd;

	v4l_info(client, "chip found @ 0x%x (%s)\n",
	client->addr << 1, client->adapter->name);

	decoder = devm_kzalloc(&client->dev, sizeof(*decoder), GFP_KERNEL);
	if (!decoder)
	return -ENOMEM;

	sd = &decoder->sd;
	v4l2_i2c_subdev_init(sd, client, &saa7191_ops);

	err = saa7191_write_block(sd, sizeof(initseq), initseq);
	if (err) {
	printk(KERN_ERR "SAA7191 initialization failed\n");
	return err;
	}

	printk(KERN_INFO "SAA7191 initialized\n");

	decoder->input = SAA7191_INPUT_COMPOSITE;
	decoder->norm = V4L2_STD_PAL;

	err = saa7191_autodetect_norm(sd);
	if (err && (err != -EBUSY))
	printk(KERN_ERR "SAA7191: Signal auto-detection failed\n");

	return 0;
	}

	static int saa7191_remove(struct i2c_client *client)
	{
	struct v4l2_subdev *sd = i2c_get_clientdata(client);

	v4l2_device_unregister_subdev(sd);
	return 0;
	}

	static const struct i2c_device_id saa7191_id[] = {
	{ "saa7191", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, saa7191_id);

	static struct i2c_driver saa7191_driver = {
	.driver = {
	.owner = THIS_MODULE,
	.name = "saa7191",
	},
	.probe = saa7191_probe,
	.remove = saa7191_remove,
	.id_table = saa7191_id,
	};

	module_i2c_driver(saa7191_driver);