nxt2002.c

linux-2.6.15.6

/*
    Support for B2C2/BBTI Technisat Air2PC - ATSC

    Copyright (C) 2004 Taylor Jacob <[e-mail]>

    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.

*/

/*
 * This driver needs external firmware. Please use the command
 * "<kerneldir>/Documentation/dvb/get_dvb_firmware nxt2002" to
 * download/extract it, and then copy it to /usr/lib/hotplug/firmware.
 */
#define NXT2002_DEFAULT_FIRMWARE "dvb-fe-nxt2002.fw"
#define CRC_CCIT_MASK 0x1021

#include <linux/init.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/device.h>
#include <linux/firmware.h>
#include <linux/string.h>
#include <linux/slab.h>

#include "dvb_frontend.h"
#include "nxt2002.h"

struct nxt2002_state {

	struct i2c_adapter* i2c;
	struct dvb_frontend_ops ops;
	const struct nxt2002_config* config;
	struct dvb_frontend frontend;

	/* demodulator private data */
	u8 initialised:1;
};

static int debug;
#define dprintk(args...) \
	do { \
		if (debug) printk(KERN_DEBUG "nxt2002: " args); \
	} while (0)

static int i2c_writebytes (struct nxt2002_state* state, u8 reg, u8 *buf, u8 len)
{
	/* probbably a much better way or doing this */
	u8 buf2 [256],x;
	int err;
	struct i2c_msg msg = { .addr = state->config->demod_address, .flags = 0, .buf = buf2, .len = len + 1 };

	buf2[0] = reg;
	for (x = 0 ; x < len ; x++)
		buf2[x+1] = buf[x];

	if ((err = i2c_transfer (state->i2c, &msg, 1)) != 1) {
		printk ("%s: i2c write error (addr %02x, err == %i)\n",
			__FUNCTION__, state->config->demod_address, err);
		return -EREMOTEIO;
	}

	return 0;
}

static u8 i2c_readbytes (struct nxt2002_state* state, u8 reg, u8* buf, u8 len)
{
	u8 reg2 [] = { reg };

	struct i2c_msg msg [] = { { .addr = state->config->demod_address, .flags = 0, .buf = reg2, .len = 1 },
			{ .addr = state->config->demod_address, .flags = I2C_M_RD, .buf = buf, .len = len } };

	int err;

	if ((err = i2c_transfer (state->i2c, msg, 2)) != 2) {
		printk ("%s: i2c read error (addr %02x, err == %i)\n",
			__FUNCTION__, state->config->demod_address, err);
		return -EREMOTEIO;
	}

	return 0;
}

static u16 nxt2002_crc(u16 crc, u8 c)
{

	u8 i;
	u16 input = (u16) c & 0xFF;

	input<<=8;
	for(i=0 ;i<8 ;i++) {
		if((crc ^ input) & 0x8000)
			crc=(crc<<1)^CRC_CCIT_MASK;
		else
			crc<<=1;
	input<<=1;
	}
	return crc;
}

static int nxt2002_writereg_multibyte (struct nxt2002_state* state, u8 reg, u8* data, u8 len)
{
	u8 buf;
	dprintk("%s\n", __FUNCTION__);

	/* set multi register length */
	i2c_writebytes(state,0x34,&len,1);

	/* set mutli register register */
	i2c_writebytes(state,0x35,&reg,1);

	/* send the actual data */
	i2c_writebytes(state,0x36,data,len);

	/* toggle the multireg write bit*/
	buf = 0x02;
	i2c_writebytes(state,0x21,&buf,1);

	i2c_readbytes(state,0x21,&buf,1);

	if ((buf & 0x02) == 0)
		return 0;

	dprintk("Error writing multireg register %02X\n",reg);

	return 0;
}

static int nxt2002_readreg_multibyte (struct nxt2002_state* state, u8 reg, u8* data, u8 len)
{
	u8 len2;
	dprintk("%s\n", __FUNCTION__);

	/* set multi register length */
	len2 = len & 0x80;
	i2c_writebytes(state,0x34,&len2,1);

	/* set mutli register register */
	i2c_writebytes(state,0x35,&reg,1);

	/* send the actual data */
	i2c_readbytes(state,reg,data,len);

	return 0;
}

static void nxt2002_microcontroller_stop (struct nxt2002_state* state)
{
	u8 buf[2],counter = 0;
	dprintk("%s\n", __FUNCTION__);

	buf[0] = 0x80;
	i2c_writebytes(state,0x22,buf,1);

	while (counter < 20) {
		i2c_readbytes(state,0x31,buf,1);
		if (buf[0] & 0x40)
			return;
		msleep(10);
		counter++;
	}

	dprintk("Timeout waiting for micro to stop.. This is ok after firmware upload\n");
	return;
}

static void nxt2002_microcontroller_start (struct nxt2002_state* state)
{
	u8 buf;
	dprintk("%s\n", __FUNCTION__);

	buf = 0x00;
	i2c_writebytes(state,0x22,&buf,1);
}

static int nxt2002_writetuner (struct nxt2002_state* state, u8* data)
{
	u8 buf,count = 0;

	dprintk("Tuner Bytes: %02X %02X %02X %02X\n",data[0],data[1],data[2],data[3]);

	dprintk("%s\n", __FUNCTION__);
	/* stop the micro first */
	nxt2002_microcontroller_stop(state);

	/* set the i2c transfer speed to the tuner */
	buf = 0x03;
	i2c_writebytes(state,0x20,&buf,1);

	/* setup to transfer 4 bytes via i2c */
	buf = 0x04;
	i2c_writebytes(state,0x34,&buf,1);

	/* write actual tuner bytes */
	i2c_writebytes(state,0x36,data,4);

	/* set tuner i2c address */
	buf = 0xC2;
	i2c_writebytes(state,0x35,&buf,1);

	/* write UC Opmode to begin transfer */
	buf = 0x80;
	i2c_writebytes(state,0x21,&buf,1);

	while (count < 20) {
		i2c_readbytes(state,0x21,&buf,1);
		if ((buf & 0x80)== 0x00)
			return 0;
		msleep(100);
		count++;
	}

	printk("nxt2002: timeout error writing tuner\n");
	return 0;
}

static void nxt2002_agc_reset(struct nxt2002_state* state)
{
	u8 buf;
	dprintk("%s\n", __FUNCTION__);

	buf = 0x08;
	i2c_writebytes(state,0x08,&buf,1);

	buf = 0x00;
	i2c_writebytes(state,0x08,&buf,1);

	return;
}

static int nxt2002_load_firmware (struct dvb_frontend* fe, const struct firmware *fw)
{

	struct nxt2002_state* state = fe->demodulator_priv;
	u8 buf[256],written = 0,chunkpos = 0;
	u16 rambase,position,crc = 0;

	dprintk("%s\n", __FUNCTION__);
	dprintk("Firmware is %zu bytes\n",fw->size);

	/* Get the RAM base for this nxt2002 */
	i2c_readbytes(state,0x10,buf,1);

	if (buf[0] & 0x10)
		rambase = 0x1000;
	else
		rambase = 0x0000;

	dprintk("rambase on this nxt2002 is %04X\n",rambase);

	/* Hold the micro in reset while loading firmware */
	buf[0] = 0x80;
	i2c_writebytes(state,0x2B,buf,1);

	for (position = 0; position < fw->size ; position++) {
		if (written == 0) {
			crc = 0;
			chunkpos = 0x28;
			buf[0] = ((rambase + position) >> 8);
			buf[1] = (rambase + position) & 0xFF;
			buf[2] = 0x81;
			/* write starting address */
			i2c_writebytes(state,0x29,buf,3);
		}
		written++;
		chunkpos++;

		if ((written % 4) == 0)
			i2c_writebytes(state,chunkpos,&fw->data[position-3],4);

		crc = nxt2002_crc(crc,fw->data[position]);

		if ((written == 255) || (position+1 == fw->size)) {
			/* write remaining bytes of firmware */
			i2c_writebytes(state, chunkpos+4-(written %4),
				&fw->data[position-(written %4) + 1],
				written %4);
			buf[0] = crc << 8;
			buf[1] = crc & 0xFF;

			/* write crc */
			i2c_writebytes(state,0x2C,buf,2);

			/* do a read to stop things */
			i2c_readbytes(state,0x2A,buf,1);

			/* set transfer mode to complete */
			buf[0] = 0x80;
			i2c_writebytes(state,0x2B,buf,1);

			written = 0;
		}
	}

	printk ("done.\n");
	return 0;
};

static int nxt2002_setup_frontend_parameters (struct dvb_frontend* fe,
					     struct dvb_frontend_parameters *p)
{
	struct nxt2002_state* state = fe->demodulator_priv;
	u32 freq = 0;
	u16 tunerfreq = 0;
	u8 buf[4];

	freq = 44000 + ( p->frequency / 1000 );

	dprintk("freq = %d      p->frequency = %d\n",freq,p->frequency);

	tunerfreq = freq * 24/4000;

	buf[0] = (tunerfreq >> 8) & 0x7F;
	buf[1] = (tunerfreq & 0xFF);

	if (p->frequency <= 214000000) {
		buf[2] = 0x84 + (0x06 << 3);
		buf[3] = (p->frequency <= 172000000) ? 0x01 : 0x02;
	} else if (p->frequency <= 721000000) {
		buf[2] = 0x84 + (0x07 << 3);
		buf[3] = (p->frequency <= 467000000) ? 0x02 : 0x08;
	} else if (p->frequency <= 841000000) {
		buf[2] = 0x84 + (0x0E << 3);
		buf[3] = 0x08;
	} else {
		buf[2] = 0x84 + (0x0F << 3);
		buf[3] = 0x02;
	}

	/* write frequency information */
	nxt2002_writetuner(state,buf);

	/* reset the agc now that tuning has been completed */
	nxt2002_agc_reset(state);

	/* set target power level */
	switch (p->u.vsb.modulation) {
		case QAM_64:
		case QAM_256:
				buf[0] = 0x74;
				break;