Copyright (C) 2002 Peter Hettkamp <peter.hettkamp@htp-tel.de> based on work Copyright (C) 1999 Convergence Integrated Media GmbH <ralph@convergence.de>
staticint debug; #define dprintk(args...) \ do { \ if (debug) printk(KERN_DEBUG "cx24110: " args); \
} while (0)
staticstruct {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 default */
{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 */
};
staticint 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;
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;
}
/* 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) return -EINVAL;
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 */
} return 0;
}
staticenum fe_code_rate 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;
}
}
staticconst u32 bands[] = {5000000UL, 15000000UL, 90999000UL/2}; int i;
dprintk("cx24110 debug: entering %s(%d)\n",__func__,srate); if (srate>90999000UL/2)
srate=90999000UL/2; if (srate<500000)
srate=500000;
for(i = 0; (i < ARRAY_SIZE(bands)) && (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;
} elseif(srate<60666000UL/2) { /* sample rate 60MHz */
cx24110_writereg(state,0x07,tmp|0x1);
cx24110_writereg(state,0x06,0xa5);
fclk=60666000UL;
} elseif(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);
/* 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... */
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,buf[0]);
/* wait for the send to be completed */ while ((cx24110_readreg(state,0x6d)&0xc0)==0x80)
;
/* send another 8 bytes */
cx24110_writereg(state,0x72,buf[1]); while ((cx24110_readreg(state,0x6d)&0xc0)==0x80)
;
/* and the topmost 5 bits of this byte */
cx24110_writereg(state,0x72,buf[2]); while ((cx24110_readreg(state,0x6d)&0xc0)==0x80)
;
/* now strobe the enable line once */
cx24110_writereg(state,0x6d,0x32);
cx24110_writereg(state,0x6d,0x30);
/* 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;
/* 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;
/* 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;
/* 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; elseif (sclk==1) sclk=60666000L; elseif (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);
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