[media] tda18271: prog_cal and prog_tab variables should be s32, not u8

Fix type of prog_cal and prog_tab variables to avoid any possible
calculation errors.

Signed-off-by: Michael Krufky <mkrufky@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/common/tuners/tda18271-fe.c b/drivers/media/common/tuners/tda18271-fe.c
index 42105d1..d884f5e 100644
--- a/drivers/media/common/tuners/tda18271-fe.c
+++ b/drivers/media/common/tuners/tda18271-fe.c
@@ -579,8 +579,8 @@
 #define RF3 2
 	u32 rf_default[3];
 	u32 rf_freq[3];
-	u8 prog_cal[3];
-	u8 prog_tab[3];
+	s32 prog_cal[3];
+	s32 prog_tab[3];
 
 	i = tda18271_lookup_rf_band(fe, &freq, NULL);
 
@@ -602,32 +602,33 @@
 			return bcal;
 
 		tda18271_calc_rf_cal(fe, &rf_freq[rf]);
-		prog_tab[rf] = regs[R_EB14];
+		prog_tab[rf] = (s32)regs[R_EB14];
 
 		if (1 == bcal)
-			prog_cal[rf] = tda18271_calibrate_rf(fe, rf_freq[rf]);
+			prog_cal[rf] =
+				(s32)tda18271_calibrate_rf(fe, rf_freq[rf]);
 		else
 			prog_cal[rf] = prog_tab[rf];
 
 		switch (rf) {
 		case RF1:
 			map[i].rf_a1 = 0;
-			map[i].rf_b1 = (s32)(prog_cal[RF1] - prog_tab[RF1]);
+			map[i].rf_b1 = (prog_cal[RF1] - prog_tab[RF1]);
 			map[i].rf1   = rf_freq[RF1] / 1000;
 			break;
 		case RF2:
-			dividend = (s32)(prog_cal[RF2] - prog_tab[RF2] -
-					 prog_cal[RF1] + prog_tab[RF1]);
+			dividend = (prog_cal[RF2] - prog_tab[RF2] -
+				    prog_cal[RF1] + prog_tab[RF1]);
 			divisor = (s32)(rf_freq[RF2] - rf_freq[RF1]) / 1000;
 			map[i].rf_a1 = (dividend / divisor);
 			map[i].rf2   = rf_freq[RF2] / 1000;
 			break;
 		case RF3:
-			dividend = (s32)(prog_cal[RF3] - prog_tab[RF3] -
-					 prog_cal[RF2] + prog_tab[RF2]);
+			dividend = (prog_cal[RF3] - prog_tab[RF3] -
+				    prog_cal[RF2] + prog_tab[RF2]);
 			divisor = (s32)(rf_freq[RF3] - rf_freq[RF2]) / 1000;
 			map[i].rf_a2 = (dividend / divisor);
-			map[i].rf_b2 = (s32)(prog_cal[RF2] - prog_tab[RF2]);
+			map[i].rf_b2 = (prog_cal[RF2] - prog_tab[RF2]);
 			map[i].rf3   = rf_freq[RF3] / 1000;
 			break;
 		default: