[media] stb6100: Improve tuner performance
- Reduce the amount of white noise present, which causes the
demodulator a significant time to acquire a frontend lock
on a whole. Frontend shows a large significant improvement in
performance.
Thanks to Peter Nayler for helping to identify the potential
hotspots and fixing them.
Signed-off-by: Manu Abraham <manu@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/dvb/frontends/stb6100.c b/drivers/media/dvb/frontends/stb6100.c
index 80a9e4c..db66248 100644
--- a/drivers/media/dvb/frontends/stb6100.c
+++ b/drivers/media/dvb/frontends/stb6100.c
@@ -51,7 +51,7 @@
if (x > y) \
printk(format, ##arg); \
} \
-} while(0)
+} while (0)
struct stb6100_lkup {
u32 val_low;
@@ -157,13 +157,25 @@
u8 regs[STB6100_NUMREGS];
int rc;
+ struct i2c_msg msg = {
+ .addr = state->config->tuner_address + reg,
+ .flags = I2C_M_RD,
+ .buf = regs,
+ .len = 1
+ };
+
+ rc = i2c_transfer(state->i2c, &msg, 1);
+
if (unlikely(reg >= STB6100_NUMREGS)) {
dprintk(verbose, FE_ERROR, 1, "Invalid register offset 0x%x", reg);
return -EINVAL;
}
- if ((rc = stb6100_read_regs(state, regs)) < 0)
- return rc;
- return (unsigned int)regs[reg];
+ if (unlikely(verbose > FE_DEBUG)) {
+ dprintk(verbose, FE_DEBUG, 1, " Read from 0x%02x", state->config->tuner_address);
+ dprintk(verbose, FE_DEBUG, 1, " %s: 0x%02x", stb6100_regnames[reg], regs[0]);
+ }
+
+ return (unsigned int)regs[0];
}
static int stb6100_write_reg_range(struct stb6100_state *state, u8 buf[], int start, int len)
@@ -211,20 +223,17 @@
return stb6100_write_reg_range(state, &data, reg, 1);
}
-static int stb6100_write_regs(struct stb6100_state *state, u8 regs[])
-{
- stb6100_normalise_regs(regs);
- return stb6100_write_reg_range(state, ®s[1], 1, STB6100_NUMREGS - 1);
-}
static int stb6100_get_status(struct dvb_frontend *fe, u32 *status)
{
int rc;
struct stb6100_state *state = fe->tuner_priv;
- if ((rc = stb6100_read_reg(state, STB6100_LD)) < 0)
+ rc = stb6100_read_reg(state, STB6100_LD);
+ if (rc < 0) {
+ dprintk(verbose, FE_ERROR, 1, "%s failed", __func__);
return rc;
-
+ }
return (rc & STB6100_LD_LOCK) ? TUNER_STATUS_LOCKED : 0;
}
@@ -234,7 +243,8 @@
u8 f;
struct stb6100_state *state = fe->tuner_priv;
- if ((rc = stb6100_read_reg(state, STB6100_F)) < 0)
+ rc = stb6100_read_reg(state, STB6100_F);
+ if (rc < 0)
return rc;
f = rc & STB6100_F_F;
@@ -265,14 +275,21 @@
/* Turn on LPF bandwidth setting clock control,
* set bandwidth, wait 10ms, turn off.
*/
- if ((rc = stb6100_write_reg(state, STB6100_FCCK, 0x0d | STB6100_FCCK_FCCK)) < 0)
+ rc = stb6100_write_reg(state, STB6100_FCCK, 0x0d | STB6100_FCCK_FCCK);
+ if (rc < 0)
return rc;
- if ((rc = stb6100_write_reg(state, STB6100_F, 0xc0 | tmp)) < 0)
+ rc = stb6100_write_reg(state, STB6100_F, 0xc0 | tmp);
+ if (rc < 0)
return rc;
- msleep(1);
- if ((rc = stb6100_write_reg(state, STB6100_FCCK, 0x0d)) < 0)
+
+ msleep(5); /* This is dangerous as another (related) thread may start */
+
+ rc = stb6100_write_reg(state, STB6100_FCCK, 0x0d);
+ if (rc < 0)
return rc;
+ msleep(10); /* This is dangerous as another (related) thread may start */
+
return 0;
}
@@ -284,7 +301,8 @@
struct stb6100_state *state = fe->tuner_priv;
u8 regs[STB6100_NUMREGS];
- if ((rc = stb6100_read_regs(state, regs)) < 0)
+ rc = stb6100_read_regs(state, regs);
+ if (rc < 0)
return rc;
odiv = (regs[STB6100_VCO] & STB6100_VCO_ODIV) >> STB6100_VCO_ODIV_SHIFT;
@@ -312,8 +330,7 @@
u8 regs[STB6100_NUMREGS];
u8 g, psd2, odiv;
- if ((rc = stb6100_read_regs(state, regs)) < 0)
- return rc;
+ dprintk(verbose, FE_DEBUG, 1, "Version 2010-8-14 13:51");
if (fe->ops.get_frontend) {
dprintk(verbose, FE_DEBUG, 1, "Get frontend parameters");
@@ -321,96 +338,140 @@
}
srate = p.u.qpsk.symbol_rate;
- regs[STB6100_DLB] = 0xdc;
- /* Disable LPEN */
- regs[STB6100_LPEN] &= ~STB6100_LPEN_LPEN; /* PLL Loop disabled */
+ /* Set up tuner cleanly, LPF calibration on */
+ rc = stb6100_write_reg(state, STB6100_FCCK, 0x4d | STB6100_FCCK_FCCK);
+ if (rc < 0)
+ return rc; /* allow LPF calibration */
- if ((rc = stb6100_write_regs(state, regs)) < 0)
+ /* PLL Loop disabled, bias on, VCO on, synth on */
+ regs[STB6100_LPEN] = 0xeb;
+ rc = stb6100_write_reg(state, STB6100_LPEN, regs[STB6100_LPEN]);
+ if (rc < 0)
return rc;
- /* Baseband gain. */
- if (srate >= 15000000)
- g = 9; // +4 dB
- else if (srate >= 5000000)
- g = 11; // +8 dB
- else
- g = 14; // +14 dB
-
- regs[STB6100_G] = (regs[STB6100_G] & ~STB6100_G_G) | g;
- regs[STB6100_G] &= ~STB6100_G_GCT; /* mask GCT */
- regs[STB6100_G] |= (1 << 5); /* 2Vp-p Mode */
+ /* Program the registers with their data values */
/* VCO divide ratio (LO divide ratio, VCO prescaler enable). */
if (frequency <= 1075000)
odiv = 1;
else
odiv = 0;
- regs[STB6100_VCO] = (regs[STB6100_VCO] & ~STB6100_VCO_ODIV) | (odiv << STB6100_VCO_ODIV_SHIFT);
- if ((frequency > 1075000) && (frequency <= 1325000))
- psd2 = 0;
- else
- psd2 = 1;
- regs[STB6100_K] = (regs[STB6100_K] & ~STB6100_K_PSD2) | (psd2 << STB6100_K_PSD2_SHIFT);
+ /* VCO enabled, seach clock off as per LL3.7, 3.4.1 */
+ regs[STB6100_VCO] = 0xe0 | (odiv << STB6100_VCO_ODIV_SHIFT);
/* OSM */
for (ptr = lkup;
(ptr->val_high != 0) && !CHKRANGE(frequency, ptr->val_low, ptr->val_high);
ptr++);
+
if (ptr->val_high == 0) {
printk(KERN_ERR "%s: frequency out of range: %u kHz\n", __func__, frequency);
return -EINVAL;
}
regs[STB6100_VCO] = (regs[STB6100_VCO] & ~STB6100_VCO_OSM) | ptr->reg;
+ rc = stb6100_write_reg(state, STB6100_VCO, regs[STB6100_VCO]);
+ if (rc < 0)
+ return rc;
+ if ((frequency > 1075000) && (frequency <= 1325000))
+ psd2 = 0;
+ else
+ psd2 = 1;
/* F(VCO) = F(LO) * (ODIV == 0 ? 2 : 4) */
fvco = frequency << (1 + odiv);
/* N(I) = floor(f(VCO) / (f(XTAL) * (PSD2 ? 2 : 1))) */
nint = fvco / (state->reference << psd2);
/* N(F) = round(f(VCO) / f(XTAL) * (PSD2 ? 2 : 1) - N(I)) * 2 ^ 9 */
nfrac = DIV_ROUND_CLOSEST((fvco - (nint * state->reference << psd2))
- << (9 - psd2),
- state->reference);
+ << (9 - psd2), state->reference);
+
+ /* NI */
+ regs[STB6100_NI] = nint;
+ rc = stb6100_write_reg(state, STB6100_NI, regs[STB6100_NI]);
+ if (rc < 0)
+ return rc;
+
+ /* NF */
+ regs[STB6100_NF_LSB] = nfrac;
+ rc = stb6100_write_reg(state, STB6100_NF_LSB, regs[STB6100_NF_LSB]);
+ if (rc < 0)
+ return rc;
+
+ /* K */
+ regs[STB6100_K] = (0x38 & ~STB6100_K_PSD2) | (psd2 << STB6100_K_PSD2_SHIFT);
+ regs[STB6100_K] = (regs[STB6100_K] & ~STB6100_K_NF_MSB) | ((nfrac >> 8) & STB6100_K_NF_MSB);
+ rc = stb6100_write_reg(state, STB6100_K, regs[STB6100_K]);
+ if (rc < 0)
+ return rc;
+
+ /* G Baseband gain. */
+ if (srate >= 15000000)
+ g = 9; /* +4 dB */
+ else if (srate >= 5000000)
+ g = 11; /* +8 dB */
+ else
+ g = 14; /* +14 dB */
+
+ regs[STB6100_G] = (0x10 & ~STB6100_G_G) | g;
+ regs[STB6100_G] &= ~STB6100_G_GCT; /* mask GCT */
+ regs[STB6100_G] |= (1 << 5); /* 2Vp-p Mode */
+ rc = stb6100_write_reg(state, STB6100_G, regs[STB6100_G]);
+ if (rc < 0)
+ return rc;
+
+ /* F we don't write as it is set up in BW set */
+
+ /* DLB set DC servo loop BW to 160Hz (LLA 3.8 / 2.1) */
+ regs[STB6100_DLB] = 0xcc;
+ rc = stb6100_write_reg(state, STB6100_DLB, regs[STB6100_DLB]);
+ if (rc < 0)
+ return rc;
+
dprintk(verbose, FE_DEBUG, 1,
"frequency = %u, srate = %u, g = %u, odiv = %u, psd2 = %u, fxtal = %u, osm = %u, fvco = %u, N(I) = %u, N(F) = %u",
frequency, srate, (unsigned int)g, (unsigned int)odiv,
(unsigned int)psd2, state->reference,
ptr->reg, fvco, nint, nfrac);
- regs[STB6100_NI] = nint;
- regs[STB6100_NF_LSB] = nfrac;
- regs[STB6100_K] = (regs[STB6100_K] & ~STB6100_K_NF_MSB) | ((nfrac >> 8) & STB6100_K_NF_MSB);
- regs[STB6100_VCO] |= STB6100_VCO_OSCH; /* VCO search enabled */
- regs[STB6100_VCO] |= STB6100_VCO_OCK; /* VCO search clock off */
- regs[STB6100_FCCK] |= STB6100_FCCK_FCCK; /* LPF BW setting clock enabled */
- regs[STB6100_LPEN] &= ~STB6100_LPEN_LPEN; /* PLL loop disabled */
- /* Power up. */
- regs[STB6100_LPEN] |= STB6100_LPEN_SYNP | STB6100_LPEN_OSCP | STB6100_LPEN_BEN;
- msleep(2);
- if ((rc = stb6100_write_regs(state, regs)) < 0)
+ /* Set up the test registers */
+ regs[STB6100_TEST1] = 0x8f;
+ rc = stb6100_write_reg(state, STB6100_TEST1, regs[STB6100_TEST1]);
+ if (rc < 0)
+ return rc;
+ regs[STB6100_TEST3] = 0xde;
+ rc = stb6100_write_reg(state, STB6100_TEST3, regs[STB6100_TEST3]);
+ if (rc < 0)
+ return rc;
+
+ /* Bring up tuner according to LLA 3.7 3.4.1, step 2 */
+ regs[STB6100_LPEN] = 0xfb; /* PLL Loop enabled, bias on, VCO on, synth on */
+ rc = stb6100_write_reg(state, STB6100_LPEN, regs[STB6100_LPEN]);
+ if (rc < 0)
return rc;
msleep(2);
- regs[STB6100_LPEN] |= STB6100_LPEN_LPEN; /* PLL loop enabled */
- if ((rc = stb6100_write_reg(state, STB6100_LPEN, regs[STB6100_LPEN])) < 0)
- return rc;
+ /* Bring up tuner according to LLA 3.7 3.4.1, step 3 */
regs[STB6100_VCO] &= ~STB6100_VCO_OCK; /* VCO fast search */
- if ((rc = stb6100_write_reg(state, STB6100_VCO, regs[STB6100_VCO])) < 0)
+ rc = stb6100_write_reg(state, STB6100_VCO, regs[STB6100_VCO]);
+ if (rc < 0)
return rc;
- msleep(10); /* wait for LO to lock */
+ msleep(10); /* This is dangerous as another (related) thread may start */ /* wait for LO to lock */
+
regs[STB6100_VCO] &= ~STB6100_VCO_OSCH; /* vco search disabled */
regs[STB6100_VCO] |= STB6100_VCO_OCK; /* search clock off */
- if ((rc = stb6100_write_reg(state, STB6100_VCO, regs[STB6100_VCO])) < 0)
- return rc;
- regs[STB6100_FCCK] &= ~STB6100_FCCK_FCCK; /* LPF BW clock disabled */
- stb6100_normalise_regs(regs);
- if ((rc = stb6100_write_reg_range(state, ®s[1], 1, STB6100_NUMREGS - 3)) < 0)
+ rc = stb6100_write_reg(state, STB6100_VCO, regs[STB6100_VCO]);
+ if (rc < 0)
return rc;
- msleep(100);
+ rc = stb6100_write_reg(state, STB6100_FCCK, 0x0d);
+ if (rc < 0)
+ return rc; /* Stop LPF calibration */
+ msleep(10); /* This is dangerous as another (related) thread may start */
+ /* wait for stabilisation, (should not be necessary) */
return 0;
}
@@ -433,8 +494,8 @@
state->bandwidth = status->bandwidth * 1000; /* Hz */
state->reference = status->refclock / 1000; /* kHz */
- /* Set default bandwidth. */
- return stb6100_set_bandwidth(fe, state->bandwidth);
+ /* Set default bandwidth. Modified, PN 13-May-10 */
+ return 0;
}
static int stb6100_get_state(struct dvb_frontend *fe,