Neels Hofmeyr has uploaded this change for review. (
https://gerrit.osmocom.org/10701
Change subject: lchan: pick proper power and ta values
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lchan: pick proper power and ta values
When activating an lchan, the power levels should be maximum and TA zero. Only
if a new lchan is assigned within the same cell does it make sense to take over
the previous power and TA levels.
In LCHAN_EV_ACTIVATE:
- Separate the code that copies previous encryption data. This should happen
regardless of whether we're staying in the same cell or not.
- For the power,TA levels, take over an old lchan's values only when it is
assigning a new lchan in the same cell.
Change-Id: I360b003398487fa6f934296ff03643c33ec61a35
---
M src/osmo-bsc/lchan_fsm.c
1 file changed, 15 insertions(+), 6 deletions(-)
git pull ssh://gerrit.osmocom.org:29418/osmo-bsc refs/changes/01/10701/1
diff --git a/src/osmo-bsc/lchan_fsm.c b/src/osmo-bsc/lchan_fsm.c
index 3352da5..7d47380 100644
--- a/src/osmo-bsc/lchan_fsm.c
+++ b/src/osmo-bsc/lchan_fsm.c
@@ -429,6 +429,8 @@
{
struct lchan_activate_info *info = data;
struct gsm_lchan *lchan = lchan_fi_lchan(fi);
+ struct gsm_bts *bts = lchan->ts->trx->bts;
+
switch (event) {
case LCHAN_EV_ACTIVATE:
@@ -446,18 +448,25 @@
lchan->activate.concluded = false;
lchan->activate.re_use_mgw_endpoint_from_lchan =
info->old_lchan;
- if (info->old_lchan) {
+ if (info->old_lchan)
lchan->encr = info->old_lchan->encr;
+ else {
+ lchan->encr = (struct gsm_encr){
+ .alg_id = RSL_ENC_ALG_A5(0), /* no
encryption */
+ };
+ }
+
+ /* If there is a previous lchan, and the new lchan is on the
same cell as previous one,
+ * take over power and TA values. Otherwise, use max power and
zero TA. */
+ if (info->old_lchan && info->old_lchan->ts->trx->bts == bts) {
lchan->ms_power = info->old_lchan->ms_power;
lchan->bs_power = info->old_lchan->bs_power;
lchan->rqd_ta = info->old_lchan->rqd_ta;
} else {
- struct gsm_bts *bts = lchan->ts->trx->bts;
- lchan->encr = (struct gsm_encr){
- .alg_id = RSL_ENC_ALG_A5(0), /* no
encryption */
- };
lchan->ms_power = ms_pwr_ctl_lvl(bts->band,
bts->ms_max_power);
- lchan->bs_power = 0; /* 0dB reduction, output power =
Pn */
+ /* From lchan_reset():
+ * - bs_power is still zero, 0dB reduction, output
power = Pn.
+ * - TA is still zero, to be determined by RACH. */
}
if (info->chan_mode == GSM48_CMODE_SPEECH_AMR)
--
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Gerrit-Project: osmo-bsc
Gerrit-Branch: master
Gerrit-MessageType: newchange
Gerrit-Change-Id: I360b003398487fa6f934296ff03643c33ec61a35
Gerrit-Change-Number: 10701
Gerrit-PatchSet: 1
Gerrit-Owner: Neels Hofmeyr <[email protected]>
