or51211.c

linux内核源码

/*
 *    Support for OR51211 (pcHDTV HD-2000) - VSB
 *
 *    Copyright (C) 2005 Kirk Lapray <[e-mail]>
 *
 *    Based on code from Jack Kelliher ([e-mail])
 *                           Copyright (C) 2002 & pcHDTV, inc.
 *
 *    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 or51211" to
 * download/extract it, and then copy it to /usr/lib/hotplug/firmware
 * or /lib/firmware (depending on configuration of firmware hotplug).
 */
#define OR51211_DEFAULT_FIRMWARE "dvb-fe-or51211.fw"

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/firmware.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <asm/byteorder.h>

#include "dvb_math.h"
#include "dvb_frontend.h"
#include "or51211.h"

static int debug;
#define dprintk(args...) \
	do { \
		if (debug) printk(KERN_DEBUG "or51211: " args); \
	} while (0)

static u8 run_buf[] = {0x7f,0x01};
static u8 cmd_buf[] = {0x04,0x01,0x50,0x80,0x06}; // ATSC

struct or51211_state {

	struct i2c_adapter* i2c;

	/* Configuration settings */
	const struct or51211_config* config;

	struct dvb_frontend frontend;
	struct bt878* bt;

	/* Demodulator private data */
	u8 initialized:1;
	u32 snr; /* Result of last SNR claculation */

	/* Tuner private data */
	u32 current_frequency;
};

static int i2c_writebytes (struct or51211_state* state, u8 reg, u8 *buf,
			   int len)
{
	int err;
	struct i2c_msg msg;
	msg.addr	= reg;
	msg.flags	= 0;
	msg.len		= len;
	msg.buf		= buf;

	if ((err = i2c_transfer (state->i2c, &msg, 1)) != 1) {
		printk(KERN_WARNING "or51211: i2c_writebytes error "
		       "(addr %02x, err == %i)\n", reg, err);
		return -EREMOTEIO;
	}

	return 0;
}

static u8 i2c_readbytes (struct or51211_state* state, u8 reg, u8* buf, int len)
{
	int err;
	struct i2c_msg msg;
	msg.addr	= reg;
	msg.flags	= I2C_M_RD;
	msg.len		= len;
	msg.buf		= buf;

	if ((err = i2c_transfer (state->i2c, &msg, 1)) != 1) {
		printk(KERN_WARNING "or51211: i2c_readbytes error "
		       "(addr %02x, err == %i)\n", reg, err);
		return -EREMOTEIO;
	}

	return 0;
}

static int or51211_load_firmware (struct dvb_frontend* fe,
				  const struct firmware *fw)
{
	struct or51211_state* state = fe->demodulator_priv;
	u8 tudata[585];
	int i;

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

	/* Get eprom data */
	tudata[0] = 17;
	if (i2c_writebytes(state,0x50,tudata,1)) {
		printk(KERN_WARNING "or51211:load_firmware error eprom addr\n");
		return -1;
	}
	if (i2c_readbytes(state,0x50,&tudata[145],192)) {
		printk(KERN_WARNING "or51211: load_firmware error eprom\n");
		return -1;
	}

	/* Create firmware buffer */
	for (i = 0; i < 145; i++)
		tudata[i] = fw->data[i];

	for (i = 0; i < 248; i++)
		tudata[i+337] = fw->data[145+i];

	state->config->reset(fe);

	if (i2c_writebytes(state,state->config->demod_address,tudata,585)) {
		printk(KERN_WARNING "or51211: load_firmware error 1\n");
		return -1;
	}
	msleep(1);

	if (i2c_writebytes(state,state->config->demod_address,
			   &fw->data[393],8125)) {
		printk(KERN_WARNING "or51211: load_firmware error 2\n");
		return -1;
	}
	msleep(1);

	if (i2c_writebytes(state,state->config->demod_address,run_buf,2)) {
		printk(KERN_WARNING "or51211: load_firmware error 3\n");
		return -1;
	}

	/* Wait at least 5 msec */
	msleep(10);
	if (i2c_writebytes(state,state->config->demod_address,run_buf,2)) {
		printk(KERN_WARNING "or51211: load_firmware error 4\n");
		return -1;
	}
	msleep(10);

	printk("or51211: Done.\n");
	return 0;
};

static int or51211_setmode(struct dvb_frontend* fe, int mode)
{
	struct or51211_state* state = fe->demodulator_priv;
	u8 rec_buf[14];

	state->config->setmode(fe, mode);

	if (i2c_writebytes(state,state->config->demod_address,run_buf,2)) {
		printk(KERN_WARNING "or51211: setmode error 1\n");
		return -1;
	}

	/* Wait at least 5 msec */
	msleep(10);
	if (i2c_writebytes(state,state->config->demod_address,run_buf,2)) {
		printk(KERN_WARNING "or51211: setmode error 2\n");
		return -1;
	}

	msleep(10);

	/* Set operation mode in Receiver 1 register;
	 * type 1:
	 * data 0x50h  Automatic sets receiver channel conditions
	 *             Automatic NTSC rejection filter
	 *             Enable  MPEG serial data output
	 *             MPEG2tr
	 *             High tuner phase noise
	 *             normal +/-150kHz Carrier acquisition range
	 */
	if (i2c_writebytes(state,state->config->demod_address,cmd_buf,3)) {
		printk(KERN_WARNING "or51211: setmode error 3\n");
		return -1;
	}

	rec_buf[0] = 0x04;
	rec_buf[1] = 0x00;
	rec_buf[2] = 0x03;
	rec_buf[3] = 0x00;
	msleep(20);
	if (i2c_writebytes(state,state->config->demod_address,rec_buf,3)) {
		printk(KERN_WARNING "or51211: setmode error 5\n");
	}
	msleep(3);
	if (i2c_readbytes(state,state->config->demod_address,&rec_buf[10],2)) {
		printk(KERN_WARNING "or51211: setmode error 6");
		return -1;
	}
	dprintk("setmode rec status %02x %02x\n",rec_buf[10],rec_buf[11]);

	return 0;
}

static int or51211_set_parameters(struct dvb_frontend* fe,
				  struct dvb_frontend_parameters *param)
{
	struct or51211_state* state = fe->demodulator_priv;

	/* Change only if we are actually changing the channel */
	if (state->current_frequency != param->frequency) {
		if (fe->ops.tuner_ops.set_params) {
			fe->ops.tuner_ops.set_params(fe, param);
			if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
		}

		/* Set to ATSC mode */
		or51211_setmode(fe,0);

		/* Update current frequency */
		state->current_frequency = param->frequency;
	}
	return 0;
}

static int or51211_read_status(struct dvb_frontend* fe, fe_status_t* status)
{
	struct or51211_state* state = fe->demodulator_priv;
	unsigned char rec_buf[2];
	unsigned char snd_buf[] = {0x04,0x00,0x03,0x00};
	*status = 0;

	/* Receiver Status */
	if (i2c_writebytes(state,state->config->demod_address,snd_buf,3)) {
		printk(KERN_WARNING "or51132: read_status write error\n");
		return -1;
	}
	msleep(3);
	if (i2c_readbytes(state,state->config->demod_address,rec_buf,2)) {
		printk(KERN_WARNING "or51132: read_status read error\n");
		return -1;
	}
	dprintk("read_status %x %x\n",rec_buf[0],rec_buf[1]);

	if (rec_buf[0] &  0x01) { /* Receiver Lock */
		*status |= FE_HAS_SIGNAL;
		*status |= FE_HAS_CARRIER;
		*status |= FE_HAS_VITERBI;
		*status |= FE_HAS_SYNC;
		*status |= FE_HAS_LOCK;
	}
	return 0;
}

/* Calculate SNR estimation (scaled by 2^24)

   8-VSB SNR equation from Oren datasheets

   For 8-VSB:
     SNR[dB] = 10 * log10(219037.9454 / MSE^2 )

   We re-write the snr equation as:
     SNR * 2^24 = 10*(c - 2*intlog10(MSE))
   Where for 8-VSB, c = log10(219037.9454) * 2^24 */

static u32 calculate_snr(u32 mse, u32 c)
{
	if (mse == 0) /* No signal */
		return 0;

	mse = 2*intlog10(mse);
	if (mse > c) {
		/* Negative SNR, which is possible, but realisticly the
		demod will lose lock before the signal gets this bad.  The
		API only allows for unsigned values, so just return 0 */
		return 0;
	}
	return 10*(c - mse);