drm/radeon: fix dual-head on rv250

Plugged in FireMV with the rv250 on it, and the second crtc/dac didn't work,
we were reading/writing different registers than we were modifying in the code.
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/radeon_legacy_encoders.c

@@ -928,16 +928,14 @@ static void radeon_legacy_tv_dac_mode_set(struct drm_encoder *encoder,
 	if (ASIC_IS_R300(rdev)) {
 		gpiopad_a = RREG32(RADEON_GPIOPAD_A) | 1;
 		disp_output_cntl = RREG32(RADEON_DISP_OUTPUT_CNTL);
-	}
-
-	if (rdev->family == CHIP_R200 || ASIC_IS_R300(rdev))
-		disp_tv_out_cntl = RREG32(RADEON_DISP_TV_OUT_CNTL);
-	else
+	} else if (rdev->family != CHIP_R200)
 		disp_hw_debug = RREG32(RADEON_DISP_HW_DEBUG);
-
-	if (rdev->family == CHIP_R200)
+	else if (rdev->family == CHIP_R200)
 		fp2_gen_cntl = RREG32(RADEON_FP2_GEN_CNTL);
 
+	if (rdev->family >= CHIP_R200)
+		disp_tv_out_cntl = RREG32(RADEON_DISP_TV_OUT_CNTL);
+
 	if (is_tv) {
 		uint32_t dac_cntl;
 
@@ -1002,15 +1000,13 @@ static void radeon_legacy_tv_dac_mode_set(struct drm_encoder *encoder,
 	if (ASIC_IS_R300(rdev)) {
 		WREG32_P(RADEON_GPIOPAD_A, gpiopad_a, ~1);
 		WREG32(RADEON_DISP_OUTPUT_CNTL, disp_output_cntl);
-	}
+	} else if (rdev->family != CHIP_R200)
+		WREG32(RADEON_DISP_HW_DEBUG, disp_hw_debug);
+	else if (rdev->family == CHIP_R200)
+		WREG32(RADEON_FP2_GEN_CNTL, fp2_gen_cntl);
 
 	if (rdev->family >= CHIP_R200)
 		WREG32(RADEON_DISP_TV_OUT_CNTL, disp_tv_out_cntl);
-	else
-		WREG32(RADEON_DISP_HW_DEBUG, disp_hw_debug);
-
-	if (rdev->family == CHIP_R200)
-		WREG32(RADEON_FP2_GEN_CNTL, fp2_gen_cntl);
 
 	if (is_tv)
 		radeon_legacy_tv_mode_set(encoder, mode, adjusted_mode);