/*
cx24110 - Single Chip Satellite Channel Receiver driver module
Copyright (C) 2002 Peter Hettkamp <peter.hettkamp@htp-tel.de> based on
work
Copyright (C) 1999 Convergence Integrated Media GmbH <ralph@convergence.de>
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.
*/
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include "dvb_frontend.h"
#include "cx24110.h"
struct cx24110_state {
struct i2c_adapter* i2c;
struct dvb_frontend_ops ops;
const struct cx24110_config* config;
struct dvb_frontend frontend;
u32 lastber;
u32 lastbler;
u32 lastesn0;
};
static int debug;
#define dprintk(args...) \
do { \
if (debug) printk(KERN_DEBUG "cx24110: " args); \
} while (0)
static struct {u8 reg; u8 data;} cx24110_regdata[]=
/* Comments beginning with @ denote this value should
be the default */
{{0x09,0x01}, /* SoftResetAll */
{0x09,0x00}, /* release reset */
{0x01,0xe8}, /* MSB of code rate 27.5MS/s */
{0x02,0x17}, /* middle byte " */
{0x03,0x29}, /* LSB " */
{0x05,0x03}, /* @ DVB mode, standard code rate 3/4 */
{0x06,0xa5}, /* @ PLL 60MHz */
{0x07,0x01}, /* @ Fclk, i.e. sampling clock, 60MHz */
{0x0a,0x00}, /* @ partial chip disables, do not set */
{0x0b,0x01}, /* set output clock in gapped mode, start signal low
active for first byte */
{0x0c,0x11}, /* no parity bytes, large hold time, serial data out */
{0x0d,0x6f}, /* @ RS Sync/Unsync thresholds */
{0x10,0x40}, /* chip doc is misleading here: write bit 6 as 1
to avoid starting the BER counter. Reset the
CRC test bit. Finite counting selected */
{0x15,0xff}, /* @ size of the limited time window for RS BER
estimation. It is <value>*256 RS blocks, this
gives approx. 2.6 sec at 27.5MS/s, rate 3/4 */
{0x16,0x00}, /* @ enable all RS output ports */
{0x17,0x04}, /* @ time window allowed for the RS to sync */
{0x18,0xae}, /* @ allow all standard DVB code rates to be scanned
for automatically */
/* leave the current code rate and normalization
registers as they are after reset... */
{0x21,0x10}, /* @ during AutoAcq, search each viterbi setting
only once */
{0x23,0x18}, /* @ size of the limited time window for Viterbi BER
estimation. It is <value>*65536 channel bits, i.e.
approx. 38ms at 27.5MS/s, rate 3/4 */
{0x24,0x24}, /* do not trigger Viterbi CRC test. Finite count window */
/* leave front-end AGC parameters at default values */
/* leave decimation AGC parameters at default values */
{0x35,0x40}, /* disable all interrupts. They are not connected anyway */
{0x36,0xff}, /* clear all interrupt pending flags */
{0x37,0x00}, /* @ fully enable AutoAcqq state machine */
{0x38,0x07}, /* @ enable fade recovery, but not autostart AutoAcq */
/* leave the equalizer parameters on their default values */
/* leave the final AGC parameters on their default values */
{0x41,0x00}, /* @ MSB of front-end derotator frequency */
{0x42,0x00}, /* @ middle bytes " */
{0x43,0x00}, /* @ LSB " */
/* leave the carrier tracking loop parameters on default */
/* leave the bit timing loop parameters at gefault */
{0x56,0x4d}, /* set the filtune voltage to 2.7V, as recommended by */
/* the cx24108 data sheet for symbol rates above 15MS/s */
{0x57,0x00}, /* @ Filter sigma delta enabled, positive */
{0x61,0x95}, /* GPIO pins 1-4 have special function */
{0x62,0x05}, /* GPIO pin 5 has special function, pin 6 is GPIO */
{0x63,0x00}, /* All GPIO pins use CMOS output characteristics */
{0x64,0x20}, /* GPIO 6 is input, all others are outputs */
{0x6d,0x30}, /* tuner auto mode clock freq 62kHz */
{0x70,0x15}, /* use auto mode, tuner word is 21 bits long */
{0x73,0x00}, /* @ disable several demod bypasses */
{0x74,0x00}, /* @ " */
{0x75,0x00} /* @ " */
/* the remaining registers are for SEC */
};
static int cx24110_writereg (struct cx24110_state* state, int reg, int data)
{
u8 buf [] = { reg, data };
struct i2c_msg msg = { .addr = state->config->demod_address, .flags = 0, .buf = buf, .len = 2 };
int err;
if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1) {
dprintk ("%s: writereg error (err == %i, reg == 0x%02x,"
" data == 0x%02x)\n", __FUNCTION__, err, reg, data);
return -EREMOTEIO;
}
return 0;
}
static int cx24110_readreg (struct cx24110_state* state, u8 reg)
{
int ret;
u8 b0 [] = { reg };
u8 b1 [] = { 0 };
struct i2c_msg msg [] = { { .addr = state->config->demod_address, .flags = 0, .buf = b0, .len = 1 },
{ .addr = state->config->demod_address, .flags = I2C_M_RD, .buf = b1, .len = 1 } };
ret = i2c_transfer(state->i2c, msg, 2);
if (ret != 2) return ret;
return b1[0];
}
static int cx24110_set_inversion (struct cx24110_state* state, fe_spectral_inversion_t inversion)
{
/* fixme (low): error handling */
switch (inversion) {
case INVERSION_OFF:
cx24110_writereg(state,0x37,cx24110_readreg(state,0x37)|0x1);
/* AcqSpectrInvDis on. No idea why someone should want this */
cx24110_writereg(state,0x5,cx24110_readreg(state,0x5)&0xf7);
/* Initial value 0 at start of acq */
cx24110_writereg(state,0x22,cx24110_readreg(state,0x22)&0xef);
/* current value 0 */
/* The cx24110 manual tells us this reg is read-only.
But what the heck... set it ayways */
break;
case INVERSION_ON:
cx24110_writereg(state,0x37,cx24110_readreg(state,0x37)|0x1);
/* AcqSpectrInvDis on. No idea why someone should want this */
cx24110_writereg(state,0x5,cx24110_readreg(state,0x5)|0x08);
/* Initial value 1 at start of acq */
cx24110_writereg(state,0x22,cx24110_readreg(state,0x22)|0x10);
/* current value 1 */
break;
case INVERSION_AUTO:
cx24110_writereg(state,0x37,cx24110_readreg(state,0x37)&0xfe);
/* AcqSpectrInvDis off. Leave initial & current states as is */
break;
default:
return -EINVAL;
}
return 0;
}
static int cx24110_set_fec (struct cx24110_state* state, fe_code_rate_t fec)
{
/* fixme (low): error handling */
static const int rate[]={-1,1,2,3,5,7,-1};
static const int g1[]={-1,0x01,0x02,0x05,0x15,0x45,-1};
static const int g2[]={-1,0x01,0x03,0x06,0x1a,0x7a,-1};
/* Well, the AutoAcq engine of the cx24106 and 24110 automatically
searches all enabled viterbi rates, and can handle non-standard
rates as well. */
if (fec>FEC_AUTO)
fec=FEC_AUTO;
if (fec==FEC_AUTO) { /* (re-)establish AutoAcq behaviour */
cx24110_writereg(state,0x37,cx24110_readreg(state,0x37)&0xdf);
/* clear AcqVitDis bit */
cx24110_writereg(state,0x18,0xae);
/* allow all DVB standard code rates */
cx24110_writereg(state,0x05,(cx24110_readreg(state,0x05)&0xf0)|0x3);
/* set nominal Viterbi rate 3/4 */
cx24110_writereg(state,0x22,(cx24110_readreg(state,0x22)&0xf0)|0x3);
/* set current Viterbi rate 3/4 */
cx24110_writereg(state,0x1a,0x05); cx24110_writereg(state,0x1b,0x06);
/* set the puncture registers for code rate 3/4 */
return 0;
} else {
cx24110_writereg(state,0x37,cx24110_readreg(state,0x37)|0x20);
/* set AcqVitDis bit */
if(rate[fec]>0) {
cx24110_writereg(state,0x05,(cx24110_readreg(state,0x05)&0xf0)|rate[fec]);
/* set nominal Viterbi rate */
cx24110_writereg(state,0x22,(cx24110_readreg(state,0x22)&0xf0)|rate[fec]);
/* set current Viterbi rate */
cx24110_writereg(state,0x1a,g1[fec]);
cx24110_writereg(state,0x1b,g2[fec]);
/* not sure if this is the right way: I always used AutoAcq mode */
} else
return -EOPNOTSUPP;
/* fixme (low): which is the correct return code? */
};
return 0;
}
static fe_code_rate_t cx24110_get_fec (struct cx24110_state* state)
{
int i;
i=cx24110_readreg(state,0x22)&0x0f;
if(!(i&0x08)) {
return FEC_1_2 + i - 1;
} else {
/* fixme (low): a special code rate has been selected. In theory, we need to
return a denominator value, a numerator value, and a pair of puncture
maps to correctly describe this mode. But this should never happen in
practice, because it cannot be set by cx24110_get_fec. */
return FEC_NONE;
}
}
static int cx24110_set_symbolrate (struct cx24110_state* state, u32 srate)
{
/* fixme (low): add error handling */
u32 ratio;
u32 tmp, fclk, BDRI;
static const u32 bands[]={5000000UL,15000000UL,90999000UL/2};
int i;
dprintk("cx24110 debug: entering %s(%d)\n",__FUNCTION__,srate);
if (srate>90999000UL/2)
srate=90999000UL/2;
if (srate<500000)
srate=500000;
for(i=0;(i<sizeof(bands)/sizeof(bands[0]))&&(srate>bands[i]);i++)
;
/* first, check which sample rate is appropriate: 45, 60 80 or 90 MHz,
and set the PLL accordingly (R07[1:0] Fclk, R06[7:4] PLLmult,
R06[3:0] PLLphaseDetGain */
tmp=cx24110_readreg(state,0x07)&0xfc;
if(srate<90999000UL/4) { /* sample rate 45MHz*/
cx24110_writereg(state,0x07,tmp);
cx24110_writereg(state,0x06,0x78);
fclk=90999000UL/2;
} else if(srate<60666000UL/2) { /* sample rate 60MHz */
cx24110_writereg(state,0x07,tmp|0x1);
cx24110_writereg(state,0x06,0xa5);
fclk=60666000UL;
} else if(srate<80888000UL/2) { /* sample rate 80MHz */
cx24110_writereg(state,0x07,tmp|0x2);
cx24110_writereg(state,0x06,0x87);
fclk=80888000UL;
} else { /* sample rate 90MHz */
cx24110_writereg(state,0x07,tmp|0x3);
cx24110_writereg(state,0x06,0x78);
fclk=90999000UL;
};
dprintk("cx24110 debug: fclk %d Hz\n",fclk);
/* we need to divide two integers with approx. 27 bits in 32 bit
arithmetic giving a 25 bit result */
/* the maximum dividend is 90999000/2, 0x02b6446c, this number is
also the most complex divisor. Hence, the dividend has,
assuming 32bit unsigned arithmetic, 6 clear bits on top, the
divisor 2 unused bits at the bottom. Also, the quotient is
always less than 1/2. Borrowed from VES1893.c, of course */
tmp=srate<<6;
BDRI=fclk>>2;
ratio=(tmp/BDRI);
tmp=(tmp%BDRI)<<8;
ratio=(ratio<<8)+(tmp/BDRI);
tmp=(tmp%BDRI)<<8;
ratio=(ratio<<8)+(tmp/BDRI);
tmp=(tmp%BDRI)<<1;
ratio=(ratio<<1)+(tmp/BDRI);
dprintk("srate= %d (range %d, up to %d)\n", srate,i,bands[i]);
dprintk("fclk = %d\n", fclk);
dprintk("ratio= %08x\n", ratio);
cx24110_writereg(state, 0x1, (ratio>>16)&0xff);
cx24110_writereg(state, 0x2, (ratio>>8)&0xff);
cx24110_writereg(state, 0x3, (ratio)&0xff);
return 0;
}
int cx24110_pll_write (struct dvb_frontend* fe, u32 data)
{
struct cx24110_state *state = fe->demodulator_priv;
/* tuner data is 21 bits long, must be left-aligned in data */
/* tuner cx24108 is written through a dedicated 3wire interface on the demod chip */
/* FIXME (low): add error handling, avoid infinite loops if HW fails... */
dprintk("cx24110 debug: cx24108_write(%8.8x)\n",data);
cx24110_writereg(state,0x6d,0x30); /* auto mode at 62kHz */
cx24110_writereg(state,0x70,0x15); /* auto mode 21 bits */
/* if the auto tuner writer is still busy, clear it out */
while (cx24110_readreg(state,0x6d)&0x80)
cx24110_writereg(state,0x72,0);
/* write the topmost 8 bits */
cx24110_writereg(state,0x72,(data>>24)&0xff);
/* wait for the send to be completed */
while ((cx24110_readreg(state,0x6d)&0xc0)==0x80)
;
/* send another 8 bytes */
cx24110_writereg(state,0x72,(data>>16)&0xff);
while ((cx24110_readreg(state,0x6d)&0xc0)==0x80)
;
/* and the topmost 5 bits of this byte */
cx24110_writereg(state,0x72,(data>>8)&0xff);
while ((cx24110_readreg(state,0x6d)&0xc0)==0x80)
;
/* now strobe the enable line once */
cx24110_writereg(state,0x6d,0x32);
cx24110_writereg(state,0x6d,0x30);
return 0;
}
static int cx24110_initfe(struct dvb_frontend* fe)
{
struct cx24110_state *state = fe->demodulator_priv;
/* fixme (low): error handling */
int i;
dprintk("%s: init chip\n", __FUNCTION__);
for(i=0;i<sizeof(cx24110_regdata)/sizeof(cx24110_regdata[0]);i++) {
cx24110_writereg(state, cx24110_regdata[i].reg, cx24110_regdata[i].data);
};
if (state->config->pll_init) state->config->pll_init(fe);
return 0;
}
static int cx24110_set_voltage (struct dvb_frontend* fe, fe_sec_voltage_t voltage)
{
struct cx24110_state *state = fe->demodulator_priv;
switch (voltage) {
case SEC_VOLTAGE_13:
return cx24110_writereg(state,0x76,(cx24110_readreg(state,0x76)&0x3b)|0xc0);
case SEC_VOLTAGE_18:
return cx24110_writereg(state,0x76,(cx24110_readreg(state,0x76)&0x3b)|0x40);
default:
return -EINVAL;
};
}
static int cx24110_diseqc_send_burst(struct dvb_frontend* fe, fe_sec_mini_cmd_t burst)
{
int rv, bit;
struct cx24110_state *state = fe->demodulator_priv;
unsigned long timeout;
if (burst == SEC_MINI_A)
bit = 0x00;
else if (burst == SEC_MINI_B)
bit = 0x08;
else
return -EINVAL;
rv = cx24110_readreg(state, 0x77);
if (!(rv & 0x04))
cx24110_writereg(state, 0x77, rv | 0x04);
rv = cx24110_readreg(state, 0x76);
cx24110_writereg(state, 0x76, ((rv & 0x90) | 0x40 | bit));
timeout = jiffies + msecs_to_jiffies(100);
while (!time_after(jiffies, timeout) && !(cx24110_readreg(state, 0x76) & 0x40))
; /* wait for LNB ready */
return 0;
}
static int cx24110_send_diseqc_msg(struct dvb_frontend* fe,
struct dvb_diseqc_master_cmd *cmd)
{
int i, rv;
struct cx24110_state *state = fe->demodulator_priv;
unsigned long timeout;
for (i = 0; i < cmd->msg_len; i++)
cx24110_writereg(state, 0x79 + i, cmd->msg[i]);
rv = cx24110_readreg(state, 0x77);
if (rv & 0x04) {
cx24110_writereg(state, 0x77, rv & ~0x04);
msleep(30); /* reportedly fixes switching problems */
}
rv = cx24110_readreg(state, 0x76);
cx24110_writereg(state, 0x76, ((rv & 0x90) | 0x40) | ((cmd->msg_len-3) & 3));
timeout = jiffies + msecs_to_jiffies(100);
while (!time_after(jiffies, timeout) && !(cx24110_readreg(state, 0x76) & 0x40))
; /* wait for LNB ready */
return 0;
}
static int cx24110_read_status(struct dvb_frontend* fe, fe_status_t* status)
{
struct cx24110_state *state = fe->demodulator_priv;
int sync = cx24110_readreg (state, 0x55);
*status = 0;
if (sync & 0x10)
*status |= FE_HAS_SIGNAL;
if (sync & 0x08)
*status |= FE_HAS_CARRIER;
sync = cx24110_readreg (state, 0x08);
if (sync & 0x40)
*status |= FE_HAS_VITERBI;
if (sync & 0x20)
*status |= FE_HAS_SYNC;
if ((sync & 0x60) == 0x60)
*status |= FE_HAS_LOCK;
return 0;
}
static int cx24110_read_ber(struct dvb_frontend* fe, u32* ber)
{
struct cx24110_state *state = fe->demodulator_priv;
/* fixme (maybe): value range is 16 bit. Scale? */
if(cx24110_readreg(state,0x24)&0x10) {
/* the Viterbi error counter has finished one counting window */
cx24110_writereg(state,0x24,0x04); /* select the ber reg */
state->lastber=cx24110_readreg(state,0x25)|
(cx24110_readreg(state,0x26)<<8);
cx24110_writereg(state,0x24,0x04); /* start new count window */
cx24110_writereg(state,0x24,0x14);
}
*ber = state->lastber;
return 0;
}
static int cx24110_read_signal_strength(struct dvb_frontend* fe, u16* signal_strength)
{
struct cx24110_state *state = fe->demodulator_priv;
/* no provision in hardware. Read the frontend AGC accumulator. No idea how to scale this, but I know it is 2s complement */
u8 signal = cx24110_readreg (state, 0x27)+128;
*signal_strength = (signal << 8) | signal;
return 0;
}
static int cx24110_read_snr(struct dvb_frontend* fe, u16* snr)
{
struct cx24110_state *state = fe->demodulator_priv;
/* no provision in hardware. Can be computed from the Es/N0 estimator, but I don't know how. */
if(cx24110_readreg(state,0x6a)&0x80) {
/* the Es/N0 error counter has finished one counting window */
state->lastesn0=cx24110_readreg(state,0x69)|
(cx24110_readreg(state,0x68)<<8);
cx24110_writereg(state,0x6a,0x84); /* start new count window */
}
*snr = state->lastesn0;
return 0;
}
static int cx24110_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
{
struct cx24110_state *state = fe->demodulator_priv;
u32 lastbyer;
if(cx24110_readreg(state,0x10)&0x40) {
/* the RS error counter has finished one counting window */
cx24110_writereg(state,0x10,0x60); /* select the byer reg */
lastbyer=cx24110_readreg(state,0x12)|
(cx24110_readreg(state,0x13)<<8)|
(cx24110_readreg(state,0x14)<<16);
cx24110_writereg(state,0x10,0x70); /* select the bler reg */
state->lastbler=cx24110_readreg(state,0x12)|
(cx24110_readreg(state,0x13)<<8)|
(cx24110_readreg(state,0x14)<<16);
cx24110_writereg(state,0x10,0x20); /* start new count window */
}
*ucblocks = state->lastbler;
return 0;
}
static int cx24110_set_frontend(struct dvb_frontend* fe, struct dvb_frontend_parameters *p)
{
struct cx24110_state *state = fe->demodulator_priv;
state->config->pll_set(fe, p);
cx24110_set_inversion (state, p->inversion);
cx24110_set_fec (state, p->u.qpsk.fec_inner);
cx24110_set_symbolrate (state, p->u.qpsk.symbol_rate);
cx24110_writereg(state,0x04,0x05); /* start aquisition */
return 0;
}
static int cx24110_get_frontend(struct dvb_frontend* fe, struct dvb_frontend_parameters *p)
{
struct cx24110_state *state = fe->demodulator_priv;
s32 afc; unsigned sclk;
/* cannot read back tuner settings (freq). Need to have some private storage */
sclk = cx24110_readreg (state, 0x07) & 0x03;
/* ok, real AFC (FEDR) freq. is afc/2^24*fsamp, fsamp=45/60/80/90MHz.
* Need 64 bit arithmetic. Is thiss possible in the kernel? */
if (sclk==0) sclk=90999000L/2L;
else if (sclk==1) sclk=60666000L;
else if (sclk==2) sclk=80888000L;
else sclk=90999000L;
sclk>>=8;
afc = sclk*(cx24110_readreg (state, 0x44)&0x1f)+
((sclk*cx24110_readreg (state, 0x45))>>8)+
((sclk*cx24110_readreg (state, 0x46))>>16);
p->frequency += afc;
p->inversion = (cx24110_readreg (state, 0x22) & 0x10) ?
INVERSION_ON : INVERSION_OFF;
p->u.qpsk.fec_inner = cx24110_get_fec (state);
return 0;
}
static int cx24110_set_tone(struct dvb_frontend* fe, fe_sec_tone_mode_t tone)
{
struct cx24110_state *state = fe->demodulator_priv;
return cx24110_writereg(state,0x76,(cx24110_readreg(state,0x76)&~0x10)|(((tone==SEC_TONE_ON))?0x10:0));
}
static void cx24110_release(struct dvb_frontend* fe)
{
struct cx24110_state* state = fe->demodulator_priv;
kfree(state);
}
static struct dvb_frontend_ops cx24110_ops;
struct dvb_frontend* cx24110_attach(const struct cx24110_config* config,
struct i2c_adapter* i2c)
{
struct cx24110_state* state = NULL;
int ret;
/* allocate memory for the internal state */
state = kmalloc(sizeof(struct cx24110_state), GFP_KERNEL);
if (state == NULL) goto error;
/* setup the state */
state->config = config;
state->i2c = i2c;
memcpy(&state->ops, &cx24110_ops, sizeof(struct dvb_frontend_ops));
state->lastber = 0;
state->lastbler = 0;
state->lastesn0 = 0;
/* check if the demod is there */
ret = cx24110_readreg(state, 0x00);
if ((ret != 0x5a) && (ret != 0x69)) goto error;
/* create dvb_frontend */
state->frontend.ops = &state->ops;
state->frontend.demodulator_priv = state;
return &state->frontend;
error:
kfree(state);
return NULL;
}
static struct dvb_frontend_ops cx24110_ops = {
.info = {
.name = "Conexant CX24110 DVB-S",
.type = FE_QPSK,
.frequency_min = 950000,
.frequency_max = 2150000,
.frequency_stepsize = 1011, /* kHz for QPSK frontends */
.frequency_tolerance = 29500,
.symbol_rate_min = 1000000,
.symbol_rate_max = 45000000,
.caps = FE_CAN_INVERSION_AUTO |
FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
FE_CAN_QPSK | FE_CAN_RECOVER
},
.release = cx24110_release,
.init = cx24110_initfe,
.set_frontend = cx24110_set_frontend,
.get_frontend = cx24110_get_frontend,
.read_status = cx24110_read_status,
.read_ber = cx24110_read_ber,
.read_signal_strength = cx24110_read_signal_strength,
.read_snr = cx24110_read_snr,
.read_ucblocks = cx24110_read_ucblocks,
.diseqc_send_master_cmd = cx24110_send_diseqc_msg,
.set_tone = cx24110_set_tone,
.set_voltage = cx24110_set_voltage,
.diseqc_send_burst = cx24110_diseqc_send_burst,
};
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
MODULE_DESCRIPTION("Conexant CX24110 DVB-S Demodulator driver");
MODULE_AUTHOR("Peter Hettkamp");
MODULE_LICENSE("GPL");
EXPORT_SYMBOL(cx24110_attach);
EXPORT_SYMBOL(cx24110_pll_write);
