From 4607bb7a472482ed985bf0a8d5a288ecd3a04ec8 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Fri, 4 Jul 2014 14:15:35 -0300 Subject: [PATCH] [media] dib8000: Fix the sleep time at the state machine msleep() is not too precise: its precision depends on the HZ config. As the driver selects precise timings for the state machine, change it to usleep_range(). Acked-By: Patrick Boettcher Signed-off-by: Mauro Carvalho Chehab --- drivers/media/dvb-frontends/dib8000.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/media/dvb-frontends/dib8000.c b/drivers/media/dvb-frontends/dib8000.c index 5d1e141d3109..91bdecc751d6 100644 --- a/drivers/media/dvb-frontends/dib8000.c +++ b/drivers/media/dvb-frontends/dib8000.c @@ -3606,10 +3606,19 @@ static int dib8000_set_frontend(struct dvb_frontend *fe) else if ((time_slave != FE_CALLBACK_TIME_NEVER) && (time_slave > time)) time = time_slave; } - if (time != FE_CALLBACK_TIME_NEVER) - msleep(time / 10); - else + if (time == FE_CALLBACK_TIME_NEVER) break; + + /* + * Despite dib8000_agc_startup returns time at a 0.1 ms range, + * the actual sleep time depends on CONFIG_HZ. The worse case + * is when CONFIG_HZ=100. In such case, the minimum granularity + * is 10ms. On some real field tests, the tuner sometimes don't + * lock when this timer is lower than 10ms. So, enforce a 10ms + * granularity. + */ + time = 10 * (time + 99)/100; + usleep_range(time * 1000, (time + 1) * 1000); exit_condition = 1; for (index_frontend = 0; (index_frontend < MAX_NUMBER_OF_FRONTENDS) && (state->fe[index_frontend] != NULL); index_frontend++) { if (dib8000_get_tune_state(state->fe[index_frontend]) != CT_AGC_STOP) { -- 2.20.1