video: tegra: dc: fix soft clipping correction

- Change "k" to be fractional part of HW_K, matching
what the algorithm assumes
- Fix reading of bin_width
- Enable soft clipping correction only if
soft clipping is enabled

Bug 1430681

Change-Id: I0c4872d7c009429d7c3c2abbac3658b5713e14c9
Signed-off-by: Daniel Solomon <daniels@nvidia.com>
Reviewed-on: http://git-master/r/361751
Reviewed-by: Jon Mayo <jmayo@nvidia.com>
Tested-by: Jon Mayo <jmayo@nvidia.com>

diff --git a/drivers/video/tegra/dc/dc_reg.h b/drivers/video/tegra/dc/dc_reg.h
index 8586d32a37ec77d0861a4caa47a5d51809696107..6309a599437a6391abdf7fc90201b32677339a74 100644 (file)
--- a/drivers/video/tegra/dc/dc_reg.h
+++ b/drivers/video/tegra/dc/dc_reg.h
@@ -4,7 +4,7 @@
  * Copyright (C) 2010 Google, Inc.
  * Author: Erik Gilling <konkers@android.com>
  *
- * Copyright (c) 2010-2012, NVIDIA CORPORATION, All rights reserved.
+ * Copyright (c) 2010-2014, NVIDIA CORPORATION, All rights reserved.
  *
  * This software is licensed under the terms of the GNU General Public
  * License version 2, as published by the Free Software Foundation, and
@@ -760,6 +760,7 @@
 #define  SD_ENABLE_ONESHOT             (2 << 0)
 #define  SD_USE_VID_LUMA               (1 << 2)
 #define  SD_BIN_WIDTH(x)               (((x) & 0x3) << 3)
+#define  SD_BIN_WIDTH_VAL(val)         (((val) & (0x3 << 3)) >> 3)
 #define  SD_BIN_WIDTH_ONE              (0 << 3)
 #define  SD_BIN_WIDTH_TWO              (1 << 3)
 #define  SD_BIN_WIDTH_FOUR             (2 << 3)

diff --git a/drivers/video/tegra/dc/nvsd.c b/drivers/video/tegra/dc/nvsd.c
index ddd5e6f86f798ffdcf8d59f8c44af7addc81f7fc..4ed4d637a2c118c393422f38e0beece28b653c12 100644 (file)
--- a/drivers/video/tegra/dc/nvsd.c
+++ b/drivers/video/tegra/dc/nvsd.c
@@ -62,6 +62,7 @@ NVSD_ATTR(sd_window_enable);
 NVSD_ATTR(sd_window);
 NVSD_ATTR(soft_clipping_enable);
 NVSD_ATTR(soft_clipping_threshold);
+NVSD_ATTR(soft_clipping_correction);
 NVSD_ATTR(smooth_k_enable);
 NVSD_ATTR(smooth_k_incr);
 NVSD_ATTR(use_vpulse2);
@@ -92,6 +93,7 @@ static struct attribute *nvsd_attrs[] = {
        NVSD_ATTRS_ENTRY(sd_window),
        NVSD_ATTRS_ENTRY(soft_clipping_enable),
        NVSD_ATTRS_ENTRY(soft_clipping_threshold),
+       NVSD_ATTRS_ENTRY(soft_clipping_correction),
        NVSD_ATTRS_ENTRY(smooth_k_enable),
        NVSD_ATTRS_ENTRY(smooth_k_incr),
        NVSD_ATTRS_ENTRY(use_vpulse2),
@@ -646,7 +648,7 @@ static int nvsd_set_brightness(struct tegra_dc *dc)
        fixed20_12 nonhisto_gain;       /* gain of pixels not in histogram */
        fixed20_12 est_achieved_gain;   /* final gain of pixels */
        fixed20_12 histo_gain = dfixed_init(0); /* gain of pixels */
-       fixed20_12 k, threshold;
+       fixed20_12 k, threshold;        /* k is the fractional part of HW_K */
        fixed20_12 den, num, out;
        fixed20_12 pix_avg, pix_avg_softclip;
 
@@ -658,13 +660,15 @@ static int nvsd_set_brightness(struct tegra_dc *dc)
        }
 
        val = tegra_dc_readl(dc, DC_DISP_SD_HW_K_VALUES);
-       k.full = SD_HW_K_R(val) << 2;
+       k.full = dfixed_const(SD_HW_K_R(val));
+       den.full = dfixed_const(1024);
+       k.full = dfixed_div(k, den);
 
        val = tegra_dc_readl(dc, DC_DISP_SD_SOFT_CLIPPING);
        threshold.full = dfixed_const(SD_SOFT_CLIPPING_THRESHOLD(val));
 
        val = tegra_dc_readl(dc, DC_DISP_SD_CONTROL);
-       bin_width = SD_BIN_WIDTH(val)>>3;
+       bin_width = SD_BIN_WIDTH_VAL(val);
        incr = 1 << bin_width;
        base = 256 - 32 * incr;
 
@@ -734,7 +738,8 @@ bool nvsd_update_brightness(struct tegra_dc *dc)
                 * if hw output is used to update brightness. */
                if (settings->phase_in_adjustments) {
                        return nvsd_phase_in_adjustments(dc, settings);
-               } else if (settings->soft_clipping_correction) {
+               } else if (settings->soft_clipping_enable &&
+                       settings->soft_clipping_correction) {
                        sw_sd_brightness = nvsd_set_brightness(dc);
                        if (sw_sd_brightness != cur_sd_brightness) {
                                atomic_set(_sd_brightness, sw_sd_brightness);
@@ -872,6 +877,9 @@ static ssize_t nvsd_settings_show(struct kobject *kobj,
                else if (IS_NVSD_ATTR(soft_clipping_threshold))
                        res = snprintf(buf, PAGE_SIZE, "%d\n",
                                sd_settings->soft_clipping_threshold);
+               else if (IS_NVSD_ATTR(soft_clipping_correction))
+                       res = snprintf(buf, PAGE_SIZE, "%d\n",
+                               sd_settings->soft_clipping_correction);
                else if (IS_NVSD_ATTR(smooth_k_enable))
                        res = snprintf(buf, PAGE_SIZE, "%d\n",
                                sd_settings->smooth_k_enable);
@@ -1060,6 +1068,8 @@ static ssize_t nvsd_settings_store(struct kobject *kobj,
                        nvsd_check_and_update(0, 1, soft_clipping_enable);
                } else if (IS_NVSD_ATTR(soft_clipping_threshold)) {
                        nvsd_check_and_update(0, 255, soft_clipping_threshold);
+               } else if (IS_NVSD_ATTR(soft_clipping_correction)) {
+                       nvsd_check_and_update(0, 1, soft_clipping_correction);
                } else if (IS_NVSD_ATTR(smooth_k_enable)) {
                        nvsd_check_and_update(0, 1, smooth_k_enable);
                } else if (IS_NVSD_ATTR(smooth_k_incr)) {