/*
    bt869.c - Part of lm_sensors, Linux kernel modules for hardware
             monitoring
    Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    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.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/


#define DEBUG 1

#include <linux/version.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/sensors.h>
#define LM_DATE "20011118"
#define LM_VERSION "2.6.2"
#include <linux/init.h>

#ifdef MODULE_LICENSE
MODULE_LICENSE("GPL");
#endif

#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,2,18)) || \
    (LINUX_VERSION_CODE == KERNEL_VERSION(2,3,0))
#define init_MUTEX(s) do { *(s) = MUTEX; } while(0)
#endif

#if LINUX_VERSION_CODE < KERNEL_VERSION(2,3,13)
#define THIS_MODULE NULL
#endif


/* Addresses to scan */
static unsigned short normal_i2c[] = { SENSORS_I2C_END };

/* found only at 0x44 or 0x45 */
static unsigned short normal_i2c_range[] = { 0x44, 0x45, SENSORS_I2C_END };
static unsigned int normal_isa[] = { SENSORS_ISA_END };
static unsigned int normal_isa_range[] = { SENSORS_ISA_END };

/* Insmod parameters */
SENSORS_INSMOD_1(bt869);

/* Many bt869 constants specified below */

/* The bt869 registers */
/* Coming soon: Many, many registers */

/* Conversions. Rounding and limit checking is only done on the TO_REG
   variants. Note that you should be a bit careful with which arguments
   these macros are called: arguments may be evaluated more than once.
   Fixing this is just not worth it. */

   /*none */

/* Initial values */
/*none*/

/* Each client has this additional data */
struct bt869_data {
	int sysctl_id;

	struct semaphore update_lock;
	char valid;		/* !=0 if following fields are valid */
	unsigned long last_updated;	/* In jiffies */

	u8 status[3];		/* Register values */
	u16 res[2];		/* Resolution XxY */
	u8 ntsc;		/* 1=NTSC, 0=PAL */
	u8 half;		/* go half res */
	u8 depth;		/* screen depth */
	u8 colorbars;		/* turn on/off colorbar calibration screen */
};

#ifdef MODULE
extern int init_module(void);
extern int cleanup_module(void);
#endif				/* MODULE */

#ifdef MODULE
static
#else
extern
#endif
int __init sensors_bt869_init(void);
static int __init bt869_cleanup(void);
static int bt869_attach_adapter(struct i2c_adapter *adapter);
static int bt869_detect(struct i2c_adapter *adapter, int address,
			unsigned short flags, int kind);
static void bt869_init_client(struct i2c_client *client);
static int bt869_detach_client(struct i2c_client *client);
static int bt869_command(struct i2c_client *client, unsigned int cmd,
			 void *arg);
static void bt869_inc_use(struct i2c_client *client);
static void bt869_dec_use(struct i2c_client *client);
static int bt869_read_value(struct i2c_client *client, u8 reg);
static int bt869_write_value(struct i2c_client *client, u8 reg, u16 value);
static void bt869_status(struct i2c_client *client, int operation,
			 int ctl_name, int *nrels_mag, long *results);
static void bt869_ntsc(struct i2c_client *client, int operation,
		       int ctl_name, int *nrels_mag, long *results);
static void bt869_res(struct i2c_client *client, int operation,
		      int ctl_name, int *nrels_mag, long *results);
static void bt869_half(struct i2c_client *client, int operation,
		       int ctl_name, int *nrels_mag, long *results);
static void bt869_colorbars(struct i2c_client *client, int operation,
			    int ctl_name, int *nrels_mag, long *results);
static void bt869_depth(struct i2c_client *client, int operation,
			int ctl_name, int *nrels_mag, long *results);
static void bt869_update_client(struct i2c_client *client);


/* This is the driver that will be inserted */
static struct i2c_driver bt869_driver = {
	/* name */ "BT869 video-output chip driver",
	/* id */ I2C_DRIVERID_BT869,
	/* flags */ I2C_DF_NOTIFY,
	/* attach_adapter */ &bt869_attach_adapter,
	/* detach_client */ &bt869_detach_client,
	/* command */ &bt869_command,
	/* inc_use */ &bt869_inc_use,
	/* dec_use */ &bt869_dec_use
};

/* These files are created for each detected bt869. This is just a template;
   though at first sight, you might think we could use a statically
   allocated list, we need some way to get back to the parent - which
   is done through one of the 'extra' fields which are initialized
   when a new copy is allocated. */
static ctl_table bt869_dir_table_template[] = {
	{BT869_SYSCTL_STATUS, "status", NULL, 0, 0444, NULL, &i2c_proc_real,
	 &i2c_sysctl_real, NULL, &bt869_status},
	{BT869_SYSCTL_NTSC, "ntsc", NULL, 0, 0644, NULL, &i2c_proc_real,
	 &i2c_sysctl_real, NULL, &bt869_ntsc},
	{BT869_SYSCTL_RES, "res", NULL, 0, 0644, NULL, &i2c_proc_real,
	 &i2c_sysctl_real, NULL, &bt869_res},
	{BT869_SYSCTL_HALF, "half", NULL, 0, 0644, NULL, &i2c_proc_real,
	 &i2c_sysctl_real, NULL, &bt869_half},
	{BT869_SYSCTL_COLORBARS, "colorbars", NULL, 0, 0644, NULL, &i2c_proc_real,
	 &i2c_sysctl_real, NULL, &bt869_colorbars},
	{BT869_SYSCTL_DEPTH, "depth", NULL, 0, 0644, NULL, &i2c_proc_real,
	 &i2c_sysctl_real, NULL, &bt869_depth},
	{0}
};

/* Used by init/cleanup */
static int __initdata bt869_initialized = 0;

int bt869_id = 0;

int bt869_attach_adapter(struct i2c_adapter *adapter)
{
	return i2c_detect(adapter, &addr_data, bt869_detect);
}

/* This function is called by i2c_detect */
int bt869_detect(struct i2c_adapter *adapter, int address,
		 unsigned short flags, int kind)
{
	int i, cur;
	struct i2c_client *new_client;
	struct bt869_data *data;
	int err = 0;
	const char *type_name, *client_name;


	printk("bt869.o:  probing address %d .\n", address);
	/* Make sure we aren't probing the ISA bus!! This is just a safety check
	   at this moment; i2c_detect really won't call us. */
#ifdef DEBUG
	if (i2c_is_isa_adapter(adapter)) {
		printk
		    ("bt869.o: bt869_detect called for an ISA bus adapter?!?\n");
		return 0;
	}
#endif

	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE |
				     I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
		    goto ERROR0;

	/* OK. For now, we presume we have a valid client. We now create the
	   client structure, even though we cannot fill it completely yet.
	   But it allows us to access bt869_{read,write}_value. */
	if (!(new_client = kmalloc(sizeof(struct i2c_client) +
				   sizeof(struct bt869_data),
				   GFP_KERNEL))) {
		err = -ENOMEM;
		goto ERROR0;
	}

	data =
	    (struct bt869_data *) (((struct i2c_client *) new_client) + 1);
	new_client->addr = address;
	new_client->data = data;
	new_client->adapter = adapter;
	new_client->driver = &bt869_driver;
	new_client->flags = 0;

	/* Now, we do the remaining detection. It is lousy. */
	i2c_smbus_write_byte_data(new_client, 0xC4, 0);	/* set status bank 0 */
	cur = i2c_smbus_read_byte(new_client);
	printk("bt869.o: address 0x%X testing-->0x%X\n", address, cur);
	if ((cur & 0xE0) != 0x20)
		goto ERROR1;

	/* Determine the chip type */
	kind = ((cur & 0x20) >> 5);

	if (kind) {
		type_name = "bt869";
		client_name = "bt869 chip";
		printk("bt869.o: BT869 detected\n");
	} else {
		type_name = "bt868";
		client_name = "bt868 chip";
		printk("bt869.o: BT868 detected\n");
	}

	/* Fill in the remaining client fields and put it into the global list */
	strcpy(new_client->name, client_name);

	new_client->id = bt869_id++;
	data->valid = 0;
	init_MUTEX(&data->update_lock);

	/* Tell the I2C layer a new client has arrived */
	if ((err = i2c_attach_client(new_client)))
		goto ERROR3;

	/* Register a new directory entry with module sensors */
	if ((i = i2c_register_entry(new_client, type_name,
					bt869_dir_table_template,
					THIS_MODULE)) < 0) {
		err = i;
		goto ERROR4;
	}
	data->sysctl_id = i;

	bt869_init_client((struct i2c_client *) new_client);
	return 0;

/* OK, this is not exactly good programming practice, usually. But it is
   very code-efficient in this case. */

      ERROR4:
	i2c_detach_client(new_client);
      ERROR3:
      ERROR1:
	kfree(new_client);
      ERROR0:
	return err;
}

int bt869_detach_client(struct i2c_client *client)
{
	int err;

	i2c_deregister_entry(((struct bt869_data *) (client->data))->
				 sysctl_id);

	if ((err = i2c_detach_client(client))) {
		printk
		    ("bt869.o: Client deregistration failed, client not detached.\n");
		return err;
	}

	kfree(client);

	return 0;
}


/* No commands defined yet */
int bt869_command(struct i2c_client *client, unsigned int cmd, void *arg)
{
	return 0;
}

/* Nothing here yet */
void bt869_inc_use(struct i2c_client *client)
{
#ifdef MODULE
	MOD_INC_USE_COUNT;
#endif
}

/* Nothing here yet */
void bt869_dec_use(struct i2c_client *client)
{
#ifdef MODULE
	MOD_DEC_USE_COUNT;
#endif
}

/* All registers are byte-sized.
   bt869 uses a high-byte first convention, which is exactly opposite to
   the usual practice. */
int bt869_read_value(struct i2c_client *client, u8 reg)
{
	return i2c_smbus_read_byte(client);
}

/* All registers are byte-sized.
   bt869 uses a high-byte first convention, which is exactly opposite to
   the usual practice. */
int bt869_write_value(struct i2c_client *client, u8 reg, u16 value)
{
	return i2c_smbus_write_byte_data(client, reg, value);
}

void bt869_init_client(struct i2c_client *client)
{
	struct bt869_data *data = client->data;

	/* Initialize the bt869 chip */
	bt869_write_value(client, 0x0ba, 0x80);
	//   bt869_write_value(client,0x0D6, 0x00);
	/* Be a slave to the clock on the Voodoo3 */
	bt869_write_value(client, 0xa0, 0x80);
	bt869_write_value(client, 0xba, 0x20);
	/* depth =16bpp */
	bt869_write_value(client, 0x0C6, 0x001);
	bt869_write_value(client, 0xC4, 1);
	/* Flicker free enable and config */
	bt869_write_value(client, 0xC8, 0);
	data->res[0] = 640;
	data->res[1] = 480;
	data->ntsc = 1;
	data->half = 0;
	data->colorbars = 0;
	data->depth = 16;

}

void bt869_update_client(struct i2c_client *client)
{
	struct bt869_data *data = client->data;

	down(&data->update_lock);

	if ((jiffies - data->last_updated > HZ + HZ / 2) ||
	    (jiffies < data->last_updated) || !data->valid) {
#ifdef DEBUG
		printk("Starting bt869 update\n");
#endif
/* Set values of device */
		if ((data->res[0] == 640) && (data->res[1] == 480)) {
			bt869_write_value(client, 0xB8, (!data->ntsc));
			bt869_write_value(client, 0xa0, 0x80 + 0x0C);
			printk("bt869.o: writing into config -->0x%X\n",
			       (0 + (!data->ntsc)));
		} else if ((data->res[0] == 800) && (data->res[1] == 600)) {
			bt869_write_value(client, 0xB8,
					  (2 + (!data->ntsc)));
			bt869_write_value(client, 0xa0, 0x80 + 0x11);
			printk("bt869.o: writing into config -->0x%X\n",
			       (2 + (!data->ntsc)));
		} else {
			bt869_write_value(client, 0xB8, (!data->ntsc));
			bt869_write_value(client, 0xa0, 0x80 + 0x0C);
			printk("bt869.o: writing into config -->0x%X\n",
			       (0 + (!data->ntsc)));
			printk
			    ("bt869.o:  Warning: arbitrary resolutions not supported yet.  Using 640x480.\n");
			data->res[0] = 640;
			data->res[1] = 480;
		}
		if ((data->depth != 24) && (data->depth != 16))
			data->depth = 16;
		if (data->depth == 16)
			bt869_write_value(client, 0x0C6, 0x001);
		if (data->depth == 24)
			bt869_write_value(client, 0x0C6, 0x000);
		bt869_write_value(client, 0xD4, data->half << 6);
		/* Be a slave to the clock on the Voodoo3 */
		bt869_write_value(client, 0xba, 0x20);
		/* depth =16bpp */
		bt869_write_value(client, 0x0C6, 0x001);
		bt869_write_value(client, 0xC4, 1);

/* Get status */
		bt869_write_value(client, 0xC4,
				  1 | (data->colorbars << 2));
		data->status[0] = bt869_read_value(client, 1);
		bt869_write_value(client, 0xC4,
				  0x41 | (data->colorbars << 2));
		data->status[1] = bt869_read_value(client, 1);
		bt869_write_value(client, 0xC4,
				  0x81 | (data->colorbars << 2));
		data->status[2] = bt869_read_value(client, 1);
		bt869_write_value(client, 0xC4,
				  0x0C1 | (data->colorbars << 2));
		data->last_updated = jiffies;
		data->valid = 1;
	}
	up(&data->update_lock);
}


void bt869_status(struct i2c_client *client, int operation, int ctl_name,
		  int *nrels_mag, long *results)
{
	struct bt869_data *data = client->data;
	if (operation == SENSORS_PROC_REAL_INFO)
		*nrels_mag = 0;
	else if (operation == SENSORS_PROC_REAL_READ) {
		bt869_update_client(client);
		results[0] = data->status[0];
		results[1] = data->status[1];
		results[2] = data->status[2];
		*nrels_mag = 3;
	} else if (operation == SENSORS_PROC_REAL_WRITE) {
		printk
		    ("bt869.o: Warning: write was requested on read-only proc file: status\n");
	}
}


void bt869_ntsc(struct i2c_client *client, int operation, int ctl_name,
		int *nrels_mag, long *results)
{
	struct bt869_data *data = client->data;
	if (operation == SENSORS_PROC_REAL_INFO)
		*nrels_mag = 0;
	else if (operation == SENSORS_PROC_REAL_READ) {
		bt869_update_client(client);
		results[0] = data->ntsc;
		*nrels_mag = 1;
	} else if (operation == SENSORS_PROC_REAL_WRITE) {
		if (*nrels_mag >= 1) {
			data->ntsc = (results[0] > 0);
		}
		bt869_update_client(client);
	}
}


void bt869_res(struct i2c_client *client, int operation, int ctl_name,
	       int *nrels_mag, long *results)
{
	struct bt869_data *data = client->data;
	if (operation == SENSORS_PROC_REAL_INFO)
		*nrels_mag = 0;
	else if (operation == SENSORS_PROC_REAL_READ) {
		bt869_update_client(client);
		results[0] = data->res[0];
		results[1] = data->res[1];
		*nrels_mag = 2;
	} else if (operation == SENSORS_PROC_REAL_WRITE) {
		if (*nrels_mag >= 1) {
			data->res[0] = results[0];
		}
		if (*nrels_mag >= 2) {
			data->res[1] = results[1];
		}
		bt869_update_client(client);
	}
}


void bt869_half(struct i2c_client *client, int operation, int ctl_name,
		int *nrels_mag, long *results)
{
	struct bt869_data *data = client->data;
	if (operation == SENSORS_PROC_REAL_INFO)
		*nrels_mag = 0;
	else if (operation == SENSORS_PROC_REAL_READ) {
		bt869_update_client(client);
		results[0] = data->half;
		*nrels_mag = 1;
	} else if (operation == SENSORS_PROC_REAL_WRITE) {
		if (*nrels_mag >= 1) {
			data->half = (results[0] > 0);
			bt869_update_client(client);
		}
	}
}

void bt869_colorbars(struct i2c_client *client, int operation,
		     int ctl_name, int *nrels_mag, long *results)
{
	struct bt869_data *data = client->data;
	if (operation == SENSORS_PROC_REAL_INFO)
		*nrels_mag = 0;
	else if (operation == SENSORS_PROC_REAL_READ) {
		bt869_update_client(client);
		results[0] = data->colorbars;
		*nrels_mag = 1;
	} else if (operation == SENSORS_PROC_REAL_WRITE) {
		if (*nrels_mag >= 1) {
			data->colorbars = (results[0] > 0);
			bt869_update_client(client);
		}
	}
}

void bt869_depth(struct i2c_client *client, int operation, int ctl_name,
		 int *nrels_mag, long *results)
{
	struct bt869_data *data = client->data;
	if (operation == SENSORS_PROC_REAL_INFO)
		*nrels_mag = 0;
	else if (operation == SENSORS_PROC_REAL_READ) {
		bt869_update_client(client);
		results[0] = data->depth;
		*nrels_mag = 1;
	} else if (operation == SENSORS_PROC_REAL_WRITE) {
		if (*nrels_mag >= 1) {
			data->depth = results[0];
			bt869_update_client(client);
		}
	}
}

int __init sensors_bt869_init(void)
{
	int res;

	printk("bt869.o version %s (%s)\n", LM_VERSION, LM_DATE);
	bt869_initialized = 0;
	if ((res = i2c_add_driver(&bt869_driver))) {
		printk
		    ("bt869.o: Driver registration failed, module not inserted.\n");
		bt869_cleanup();
		return res;
	}
	bt869_initialized++;
	return 0;
}

int __init bt869_cleanup(void)
{
	int res;

	if (bt869_initialized >= 1) {
		if ((res = i2c_del_driver(&bt869_driver))) {
			printk
			    ("bt869.o: Driver deregistration failed, module not removed.\n");
			return res;
		}
		bt869_initialized--;
	}

	return 0;
}

EXPORT_NO_SYMBOLS;

#ifdef MODULE

MODULE_AUTHOR
    ("Frodo Looijaard <frodol@dds.nl> and Philip Edelbrock <phil@netroedge.com>");
MODULE_DESCRIPTION("bt869 driver");

int init_module(void)
{
	return sensors_bt869_init();
}

int cleanup_module(void)
{
	return bt869_cleanup();
}

#endif				/* MODULE */