upstream: [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 <pboettcher@kernellabs.com>
Backports http://git.linuxtv.org/cgit.cgi/media_tree.git/commit/?id=4607bb7a4724
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

diff --git a/drivers/media/dvb-frontends/dib8000.c b/drivers/media/dvb-frontends/dib8000.c
index 5d1e141..91bdecc 100644 (file)
--- 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) {