ath5k: fix interpolation with equal power levels

When the EEPROM contains weird values for the power levels we have to
fix the interpolation process.

Signed-off-by: Fabio Rossi <rossi.f@inwind.it>
Acked-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/ath/ath5k/phy.c b/drivers/net/wireless/ath/ath5k/phy.c
index 9e2faae5ae942c81d5a857d2b9c528138370cbfa..b48b29dca3d2a6b70ad1e08479d12dea51f5a69d 100644 (file)
--- a/drivers/net/wireless/ath/ath5k/phy.c
+++ b/drivers/net/wireless/ath/ath5k/phy.c
@@ -1487,28 +1487,35 @@ ath5k_get_linear_pcdac_min(const u8 *stepL, const u8 *stepR,
 {
        s8 tmp;
        s16 min_pwrL, min_pwrR;
-       s16 pwr_i = pwrL[0];
-
-       do {
-               pwr_i--;
-               tmp = (s8) ath5k_get_interpolated_value(pwr_i,
-                                               pwrL[0], pwrL[1],
-                                               stepL[0], stepL[1]);
-
-       } while (tmp > 1);
-
-       min_pwrL = pwr_i;
-
-       pwr_i = pwrR[0];
-       do {
-               pwr_i--;
-               tmp = (s8) ath5k_get_interpolated_value(pwr_i,
-                                               pwrR[0], pwrR[1],
-                                               stepR[0], stepR[1]);
-
-       } while (tmp > 1);
+       s16 pwr_i;
+
+       if (pwrL[0] == pwrL[1])
+               min_pwrL = pwrL[0];
+       else {
+               pwr_i = pwrL[0];
+               do {
+                       pwr_i--;
+                       tmp = (s8) ath5k_get_interpolated_value(pwr_i,
+                                                       pwrL[0], pwrL[1],
+                                                       stepL[0], stepL[1]);
+               } while (tmp > 1);
+
+               min_pwrL = pwr_i;
+       }
 
-       min_pwrR = pwr_i;
+       if (pwrR[0] == pwrR[1])
+               min_pwrR = pwrR[0];
+       else {
+               pwr_i = pwrR[0];
+               do {
+                       pwr_i--;
+                       tmp = (s8) ath5k_get_interpolated_value(pwr_i,
+                                                       pwrR[0], pwrR[1],
+                                                       stepR[0], stepR[1]);
+               } while (tmp > 1);
+
+               min_pwrR = pwr_i;
+       }
 
        /* Keep the right boundary so that it works for both curves */
        return max(min_pwrL, min_pwrR);