[media] drxd: fix divide error

Fix division by zero in drxd triggered by running "femon" before any DVB
tuning has been done (by "scandvb" or anything else).

Signed-off-by: Edward Sheldrake <ejsheldrake@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Edward Sheldrake 2011-08-26 12:59:30 -03:00 committed by Mauro Carvalho Chehab
parent 133a9fe949
commit f8a26f052a
1 changed files with 9 additions and 4 deletions

View File

@ -889,10 +889,15 @@ static int ReadIFAgc(struct drxd_state *state, u32 * pValue)
u32 R2 = state->if_agc_cfg.R2;
u32 R3 = state->if_agc_cfg.R3;
u32 Vmax = (3300 * R2) / (R1 + R2);
u32 Rpar = (R2 * R3) / (R3 + R2);
u32 Vmin = (3300 * Rpar) / (R1 + Rpar);
u32 Vout = Vmin + ((Vmax - Vmin) * Value) / 1024;
u32 Vmax, Rpar, Vmin, Vout;
if (R2 == 0 && (R1 == 0 || R3 == 0))
return 0;
Vmax = (3300 * R2) / (R1 + R2);
Rpar = (R2 * R3) / (R3 + R2);
Vmin = (3300 * Rpar) / (R1 + Rpar);
Vout = Vmin + ((Vmax - Vmin) * Value) / 1024;
*pValue = Vout;
}