[media] mb86a20s: add block count measures (PER/UCB)

Add both per-layer and global block error count and block count,
for PER and UCB measurements.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 180 insertions, 10 deletions

diff --git a/drivers/media/dvb-frontends/mb86a20s.c b/drivers/media/dvb-frontends/mb86a20s.c
index 4f3e222a2bcf..c5c2c49ea99a 100644
--- a/drivers/media/dvb-frontends/mb86a20s.c
+++ b/drivers/media/dvb-frontends/mb86a20s.c
@@ -111,13 +111,21 @@ static struct regdata mb86a20s_init[] = {
         { 0x50, 0xdf }, { 0x51, 0xf4 },
         { 0x50, 0xe0 }, { 0x51, 0x01 },
         { 0x50, 0xe1 }, { 0x51, 0xf4 },
-        { 0x50, 0xb0 }, { 0x51, 0x07 },
-        { 0x50, 0xb2 }, { 0x51, 0xff },
-        { 0x50, 0xb3 }, { 0x51, 0xff },
-        { 0x50, 0xb4 }, { 0x51, 0xff },
-        { 0x50, 0xb5 }, { 0x51, 0xff },
-        { 0x50, 0xb6 }, { 0x51, 0xff },
-        { 0x50, 0xb7 }, { 0x51, 0xff },
+
+        /*
+         * On this demod, when the block count reaches the count below,
+         * it collects the block error count. The block counters are initialized
+         * to 127 here. This warrants that all of them will be quickly
+         * calculated when device gets locked. As TMCC is parsed, the values
+         * will be adjusted later in the driver's code.
+         */
+        { 0x50, 0xb0 }, { 0x51, 0x07 },         /* Enable PER */
+        { 0x50, 0xb2 }, { 0x51, 0x00 },
+        { 0x50, 0xb3 }, { 0x51, 0x7f },
+        { 0x50, 0xb4 }, { 0x51, 0x00 },
+        { 0x50, 0xb5 }, { 0x51, 0x7f },
+        { 0x50, 0xb6 }, { 0x51, 0x00 },
+        { 0x50, 0xb7 }, { 0x51, 0x7f },
 
         { 0x50, 0x50 }, { 0x51, 0x02 },         /* MER manual mode */
         { 0x50, 0x51 }, { 0x51, 0x04 },         /* MER symbol 4 */
@@ -893,6 +901,123 @@ static int mb86a20s_get_ber_before_vterbi(struct dvb_frontend *fe,
         return 0;
 }
 
+static int mb86a20s_get_blk_error(struct dvb_frontend *fe,
+                            unsigned layer,
+                            u32 *error, u32 *count)
+{
+        struct mb86a20s_state *state = fe->demodulator_priv;
+        int rc;
+        u32 collect_rate;
+        dev_dbg(&state->i2c->dev, "%s called.\n", __func__);
+
+        if (layer >= 3)
+                return -EINVAL;
+
+        /* Check if the PER measures are already available */
+        rc = mb86a20s_writereg(state, 0x50, 0xb8);
+        if (rc < 0)
+                return rc;
+        rc = mb86a20s_readreg(state, 0x51);
+        if (rc < 0)
+                return rc;
+
+        /* Check if data is available for that layer */
+
+        if (!(rc & (1 << layer))) {
+                dev_dbg(&state->i2c->dev,
+                        "%s: block counts for layer %c aren't available yet.\n",
+                        __func__, 'A' + layer);
+                return -EBUSY;
+        }
+
+        /* Read Packet error Count */
+        rc = mb86a20s_writereg(state, 0x50, 0xb9 + layer * 2);
+        if (rc < 0)
+                return rc;
+        rc = mb86a20s_readreg(state, 0x51);
+        if (rc < 0)
+                return rc;
+        *error = rc << 8;
+        rc = mb86a20s_writereg(state, 0x50, 0xba + layer * 2);
+        if (rc < 0)
+                return rc;
+        rc = mb86a20s_readreg(state, 0x51);
+        if (rc < 0)
+                return rc;
+        *error |= rc;
+        dev_err(&state->i2c->dev, "%s: block error for layer %c: %d.\n",
+                __func__, 'A' + layer, *error);
+
+        /* Read Bit Count */
+        rc = mb86a20s_writereg(state, 0x50, 0xb2 + layer * 2);
+        if (rc < 0)
+                return rc;
+        rc = mb86a20s_readreg(state, 0x51);
+        if (rc < 0)
+                return rc;
+        *count = rc << 8;
+        rc = mb86a20s_writereg(state, 0x50, 0xb3 + layer * 2);
+        if (rc < 0)
+                return rc;
+        rc = mb86a20s_readreg(state, 0x51);
+        if (rc < 0)
+                return rc;
+        *count |= rc;
+
+        dev_dbg(&state->i2c->dev,
+                "%s: block count for layer %c: %d.\n",
+                __func__, 'A' + layer, *count);
+
+        /*
+         * As we get TMCC data from the frontend, we can better estimate the
+         * BER bit counters, in order to do the BER measure during a longer
+         * time. Use those data, if available, to update the bit count
+         * measure.
+         */
+
+        if (!state->estimated_rate[layer])
+                goto reset_measurement;
+
+        collect_rate = state->estimated_rate[layer] / 204 / 8;
+
+        if (collect_rate < 32)
+                collect_rate = 32;
+        if (collect_rate > 65535)
+                collect_rate = 65535;
+
+        if (collect_rate != *count) {
+                dev_dbg(&state->i2c->dev,
+                        "%s: updating PER counter on layer %c to %d.\n",
+                        __func__, 'A' + layer, collect_rate);
+                rc = mb86a20s_writereg(state, 0x50, 0xb2 + layer * 2);
+                if (rc < 0)
+                        return rc;
+                rc = mb86a20s_writereg(state, 0x51, collect_rate >> 8);
+                if (rc < 0)
+                        return rc;
+                rc = mb86a20s_writereg(state, 0x50, 0xb3 + layer * 2);
+                if (rc < 0)
+                        return rc;
+                rc = mb86a20s_writereg(state, 0x51, collect_rate & 0xff);
+                if (rc < 0)
+                        return rc;
+        }
+
+reset_measurement:
+        /* Reset counter to collect new data */
+        rc = mb86a20s_writereg(state, 0x50, 0xb1);
+        if (rc < 0)
+                return rc;
+        rc = mb86a20s_writereg(state, 0x51, (1 << layer));
+        if (rc < 0)
+                return rc;
+        rc = mb86a20s_writereg(state, 0x51, 0x00);
+        if (rc < 0)
+                return rc;
+
+        return 0;
+}
+
 struct linear_segments {
         unsigned x, y;
 };
@@ -1115,7 +1240,7 @@ static int mb86a20s_get_main_CNR(struct dvb_frontend *fe)
         return rc;
 }
 
-static int mb86a20s_get_per_layer_CNR(struct dvb_frontend *fe)
+static int mb86a20s_get_blk_error_layer_CNR(struct dvb_frontend *fe)
 {
         struct mb86a20s_state *state = fe->demodulator_priv;
         struct dtv_frontend_properties *c = &fe->dtv_property_cache;
@@ -1258,14 +1383,16 @@ static int mb86a20s_get_stats(struct dvb_frontend *fe)
         int rc = 0, i;
         u32 bit_error = 0, bit_count = 0;
         u32 t_pre_bit_error = 0, t_pre_bit_count = 0;
-        int active_layers = 0, ber_layers = 0;
+        u32 block_error = 0, block_count = 0;
+        u32 t_block_error = 0, t_block_count = 0;
+        int active_layers = 0, ber_layers = 0, per_layers = 0;
 
         dev_dbg(&state->i2c->dev, "%s called.\n", __func__);
 
         mb86a20s_get_main_CNR(fe);
 
         /* Get per-layer stats */
-        mb86a20s_get_per_layer_CNR(fe);
+        mb86a20s_get_blk_error_layer_CNR(fe);
 
         for (i = 0; i < 3; i++) {
                 if (c->isdbt_layer_enabled & (1 << i)) {
@@ -1297,9 +1424,38 @@ static int mb86a20s_get_stats(struct dvb_frontend *fe)
                         if (c->block_error.stat[1 + i].scale != FE_SCALE_NOT_AVAILABLE)
                                 ber_layers++;
 
+                        /* Handle Block errors for PER/UCB reports */
+                        rc = mb86a20s_get_blk_error(fe, i,
+                                                &block_error,
+                                                &block_count);
+                        if (rc >= 0) {
+                                c->block_error.stat[1 + i].scale = FE_SCALE_COUNTER;
+                                c->block_error.stat[1 + i].uvalue += block_error;
+                                c->block_count.stat[1 + i].scale = FE_SCALE_COUNTER;
+                                c->block_count.stat[1 + i].uvalue += block_count;
+                        } else if (rc != -EBUSY) {
+                                /*
+                                        * If an I/O error happened,
+                                        * measures are now unavailable
+                                        */
+                                c->block_error.stat[1 + i].scale = FE_SCALE_NOT_AVAILABLE;
+                                c->block_count.stat[1 + i].scale = FE_SCALE_NOT_AVAILABLE;
+                                dev_err(&state->i2c->dev,
+                                        "%s: Can't get PER for layer %c (error %d).\n",
+                                        __func__, 'A' + i, rc);
+
+                        }
+
+                        if (c->block_error.stat[1 + i].scale != FE_SCALE_NOT_AVAILABLE)
+                                per_layers++;
+
                         /* Update total BER */
                         t_pre_bit_error += c->pre_bit_error.stat[1 + i].uvalue;
                         t_pre_bit_count += c->pre_bit_count.stat[1 + i].uvalue;
+
+                        /* Update total PER */
+                        t_block_error += c->block_error.stat[1 + i].uvalue;
+                        t_block_count += c->block_count.stat[1 + i].uvalue;
                 }
         }
 
@@ -1321,6 +1477,20 @@ static int mb86a20s_get_stats(struct dvb_frontend *fe)
                 c->pre_bit_count.stat[0].uvalue = t_pre_bit_count;
         }
 
+        if (per_layers) {
+                /*
+                 * At least one per-layer UCB measure was read. We can now
+                 * calculate the total UCB
+                 *
+                 * Total block Error/Count is calculated as the sum of the
+                 * block errors on all active layers.
+                 */
+                c->block_error.stat[0].scale = FE_SCALE_COUNTER;
+                c->block_error.stat[0].uvalue = t_block_error;
+                c->block_count.stat[0].scale = FE_SCALE_COUNTER;
+                c->block_count.stat[0].uvalue = t_block_count;
+        }
+
         return rc;
 }