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authorMauro Carvalho Chehab <mchehab@redhat.com>2013-03-20 08:21:52 -0300
committerMauro Carvalho Chehab <mchehab@redhat.com>2013-03-21 10:27:05 -0300
commit59a7a23c4755f12757fe17234c693188a9e6bcf5 (patch)
treee202191ff14e7876c0548d6e6397354a592c49de /drivers/media/dvb-frontends
parent8f3741e02831d1181be9ca0ea711dd0c8d7f8a7b (diff)
downloadvexpress-lsk-59a7a23c4755f12757fe17234c693188a9e6bcf5.tar.gz
[media] drxk: use a better calculus for RF strength
The AZ6007 driver released by Terratec has a better way to estimate the signal strength, at CtrlSigStrength(). Port it to the driver. It should be noticed that there are two parameters there that are tuner-specific. Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'drivers/media/dvb-frontends')
-rw-r--r--drivers/media/dvb-frontends/drxk_hard.c126
1 files changed, 109 insertions, 17 deletions
diff --git a/drivers/media/dvb-frontends/drxk_hard.c b/drivers/media/dvb-frontends/drxk_hard.c
index 8c4de7cc450..6e250533b62 100644
--- a/drivers/media/dvb-frontends/drxk_hard.c
+++ b/drivers/media/dvb-frontends/drxk_hard.c
@@ -6390,6 +6390,107 @@ static int drxk_set_parameters(struct dvb_frontend *fe)
return 0;
}
+static int get_strength(struct drxk_state *state, u64 *strength)
+{
+ int status;
+ struct SCfgAgc rfAgc, ifAgc;
+ u32 totalGain = 0;
+ u32 atten = 0;
+ u32 agcRange = 0;
+ u16 scu_lvl = 0;
+ u16 scu_coc = 0;
+ /* FIXME: those are part of the tuner presets */
+ u16 tunerRfGain = 50; /* Default value on az6007 driver */
+ u16 tunerIfGain = 40; /* Default value on az6007 driver */
+
+ *strength = 0;
+
+ if (IsDVBT(state)) {
+ rfAgc = state->m_dvbtRfAgcCfg;
+ ifAgc = state->m_dvbtIfAgcCfg;
+ } else if (IsQAM(state)) {
+ rfAgc = state->m_qamRfAgcCfg;
+ ifAgc = state->m_qamIfAgcCfg;
+ } else {
+ rfAgc = state->m_atvRfAgcCfg;
+ ifAgc = state->m_atvIfAgcCfg;
+ }
+
+ if (rfAgc.ctrlMode == DRXK_AGC_CTRL_AUTO) {
+ /* SCU outputLevel */
+ status = read16(state, SCU_RAM_AGC_RF_IACCU_HI__A, &scu_lvl);
+ if (status < 0)
+ return status;
+
+ /* SCU c.o.c. */
+ read16(state, SCU_RAM_AGC_RF_IACCU_HI_CO__A, &scu_coc);
+ if (status < 0)
+ return status;
+
+ if (((u32) scu_lvl + (u32) scu_coc) < 0xffff)
+ rfAgc.outputLevel = scu_lvl + scu_coc;
+ else
+ rfAgc.outputLevel = 0xffff;
+
+ /* Take RF gain into account */
+ totalGain += tunerRfGain;
+
+ /* clip output value */
+ if (rfAgc.outputLevel < rfAgc.minOutputLevel)
+ rfAgc.outputLevel = rfAgc.minOutputLevel;
+ if (rfAgc.outputLevel > rfAgc.maxOutputLevel)
+ rfAgc.outputLevel = rfAgc.maxOutputLevel;
+
+ agcRange = (u32) (rfAgc.maxOutputLevel - rfAgc.minOutputLevel);
+ if (agcRange > 0) {
+ atten += 100UL *
+ ((u32)(tunerRfGain)) *
+ ((u32)(rfAgc.outputLevel - rfAgc.minOutputLevel))
+ / agcRange;
+ }
+ }
+
+ if (ifAgc.ctrlMode == DRXK_AGC_CTRL_AUTO) {
+ status = read16(state, SCU_RAM_AGC_IF_IACCU_HI__A,
+ &ifAgc.outputLevel);
+ if (status < 0)
+ return status;
+
+ status = read16(state, SCU_RAM_AGC_INGAIN_TGT_MIN__A,
+ &ifAgc.top);
+ if (status < 0)
+ return status;
+
+ /* Take IF gain into account */
+ totalGain += (u32) tunerIfGain;
+
+ /* clip output value */
+ if (ifAgc.outputLevel < ifAgc.minOutputLevel)
+ ifAgc.outputLevel = ifAgc.minOutputLevel;
+ if (ifAgc.outputLevel > ifAgc.maxOutputLevel)
+ ifAgc.outputLevel = ifAgc.maxOutputLevel;
+
+ agcRange = (u32) (ifAgc.maxOutputLevel - ifAgc.minOutputLevel);
+ if (agcRange > 0) {
+ atten += 100UL *
+ ((u32)(tunerIfGain)) *
+ ((u32)(ifAgc.outputLevel - ifAgc.minOutputLevel))
+ / agcRange;
+ }
+ }
+
+ /*
+ * Convert to 0..65535 scale.
+ * If it can't be measured (AGC is disabled), just show 100%.
+ */
+ if (totalGain > 0)
+ *strength = (65535UL * atten / totalGain);
+ else
+ *strength = 65535;
+
+ return 0;
+}
+
static int drxk_get_stats(struct dvb_frontend *fe)
{
struct dtv_frontend_properties *c = &fe->dtv_property_cache;
@@ -6404,7 +6505,7 @@ static int drxk_get_stats(struct dvb_frontend *fe)
u32 pre_bit_count;
u32 pkt_count;
u32 pkt_error_count;
- s32 cnr, gain;
+ s32 cnr;
if (state->m_DrxkState == DRXK_NO_DEV)
return -ENODEV;
@@ -6421,6 +6522,13 @@ static int drxk_get_stats(struct dvb_frontend *fe)
if (stat == DEMOD_LOCK)
state->fe_status |= 0x07;
+ /*
+ * Estimate signal strength from AGC
+ */
+ get_strength(state, &c->strength.stat[0].uvalue);
+ c->strength.stat[0].scale = FE_SCALE_RELATIVE;
+
+
if (stat >= DEMOD_LOCK) {
GetSignalToNoise(state, &cnr);
c->cnr.stat[0].svalue = cnr * 100;
@@ -6500,22 +6608,6 @@ static int drxk_get_stats(struct dvb_frontend *fe)
c->post_bit_count.stat[0].scale = FE_SCALE_COUNTER;
c->post_bit_count.stat[0].uvalue += post_bit_count;
- /*
- * Read AGC gain
- *
- * IFgain = (IQM_AF_AGC_IF__A * 26.75) (nA)
- */
- status = read16(state, IQM_AF_AGC_IF__A, &reg16);
- if (status < 0) {
- printk(KERN_ERR "drxk: Error %d on %s\n", status, __func__);
- return status;
- }
- gain = 2675 * (reg16 - DRXK_AGC_DAC_OFFSET) / 100;
-
- /* FIXME: it makes sense to fix the scale here to dBm */
- c->strength.stat[0].scale = FE_SCALE_RELATIVE;
- c->strength.stat[0].uvalue = gain;
-
error:
return status;
}