[PATCH v4.5 3/4] drm/mediatek: Add gamma correction.
Philipp Zabel
p.zabel at pengutronix.de
Thu Aug 11 09:11:25 UTC 2016
>From 2f3f4dda747c0619594d13996e65598ab675c60c Mon Sep 17 00:00:00 2001
From: Bibby Hsieh <bibby.hsieh at mediatek.com>
Date: Thu, 28 Jul 2016 10:22:54 +0800
Subject: [PATCH] drm/mediatek: Add gamma correction.
Add gamma set function to correct brightness values.
It applies arbitrary mapping curve to compensate the
incorrect transfer function of the panel.
Signed-off-by: Bibby Hsieh <bibby.hsieh at mediatek.com>
Signed-off-by: Philipp Zabel <p.zabel at pengutronix.de>
---
I have applied this patch with one change from v4:
- Use drm_crtc_enable_color_mgmt instead of drm_crtc_helper_enable_color_mgmt
---
drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 7 ++++++-
drivers/gpu/drm/mediatek/mtk_drm_crtc.h | 1 +
drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c | 31 +++++++++++++++++++++++++++++
drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h | 10 ++++++++++
4 files changed, 48 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index 24aa3ba..e3ac280 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -409,6 +409,9 @@ static void mtk_drm_crtc_atomic_flush(struct drm_crtc *crtc,
}
if (pending_planes)
mtk_crtc->pending_planes = true;
+ if (crtc->state->color_mgmt_changed)
+ for (i = 0; i < mtk_crtc->ddp_comp_nr; i++)
+ mtk_ddp_gamma_set(mtk_crtc->ddp_comp[i], crtc->state);
}
static const struct drm_crtc_funcs mtk_crtc_funcs = {
@@ -418,6 +421,7 @@ static const struct drm_crtc_funcs mtk_crtc_funcs = {
.reset = mtk_drm_crtc_reset,
.atomic_duplicate_state = mtk_drm_crtc_duplicate_state,
.atomic_destroy_state = mtk_drm_crtc_destroy_state,
+ .gamma_set = drm_atomic_helper_legacy_gamma_set,
};
static const struct drm_crtc_helper_funcs mtk_crtc_helper_funcs = {
@@ -568,7 +572,8 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
&mtk_crtc->planes[1].base, pipe);
if (ret < 0)
goto unprepare;
-
+ drm_mode_crtc_set_gamma_size(&mtk_crtc->base, MTK_LUT_SIZE);
+ drm_crtc_enable_color_mgmt(&mtk_crtc->base, 0, false, MTK_LUT_SIZE);
priv->crtc[pipe] = &mtk_crtc->base;
priv->num_pipes++;
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
index 81e5566..d332564 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.h
@@ -19,6 +19,7 @@
#include "mtk_drm_plane.h"
#define OVL_LAYER_NR 4
+#define MTK_LUT_SIZE 512
int mtk_drm_crtc_enable_vblank(struct drm_device *drm, unsigned int pipe);
void mtk_drm_crtc_disable_vblank(struct drm_device *drm, unsigned int pipe);
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
index ba895c8..42cd587 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
@@ -24,6 +24,7 @@
#include "mtk_drm_drv.h"
#include "mtk_drm_plane.h"
#include "mtk_drm_ddp_comp.h"
+#include "mtk_drm_crtc.h"
#define DISP_OD_EN 0x0000
#define DISP_OD_INTEN 0x0008
@@ -42,7 +43,11 @@
#define DISP_AAL_SIZE 0x0030
#define DISP_GAMMA_EN 0x0000
+#define DISP_GAMMA_CFG 0x0020
#define DISP_GAMMA_SIZE 0x0030
+#define DISP_GAMMA_LUT 0x0700
+
+#define LUT_10BIT_MASK 0x03ff
#define OD_RELAY_MODE BIT(0)
@@ -54,6 +59,7 @@
#define AAL_EN BIT(0)
#define GAMMA_EN BIT(0)
+#define GAMMA_LUT_EN BIT(1)
static void mtk_color_config(struct mtk_ddp_comp *comp, unsigned int w,
unsigned int h, unsigned int vrefresh)
@@ -118,13 +124,38 @@ static void mtk_gamma_stop(struct mtk_ddp_comp *comp)
writel_relaxed(0x0, comp->regs + DISP_GAMMA_EN);
}
+static void mtk_gamma_set(struct mtk_ddp_comp *comp,
+ struct drm_crtc_state *state)
+{
+ unsigned int i, reg;
+ struct drm_color_lut *lut;
+ void __iomem *lut_base;
+ u32 word;
+
+ if (state->gamma_lut) {
+ reg = readl(comp->regs + DISP_GAMMA_CFG);
+ reg = reg | GAMMA_LUT_EN;
+ writel(reg, comp->regs + DISP_GAMMA_CFG);
+ lut_base = comp->regs + DISP_GAMMA_LUT;
+ lut = (struct drm_color_lut *)state->gamma_lut->data;
+ for (i = 0; i < MTK_LUT_SIZE; i++) {
+ word = (((lut[i].red >> 6) & LUT_10BIT_MASK) << 20) +
+ (((lut[i].green >> 6) & LUT_10BIT_MASK) << 10) +
+ ((lut[i].blue >> 6) & LUT_10BIT_MASK);
+ writel(word, (lut_base + i * 4));
+ }
+ }
+}
+
static const struct mtk_ddp_comp_funcs ddp_aal = {
+ .gamma_set = mtk_gamma_set,
.config = mtk_aal_config,
.start = mtk_aal_start,
.stop = mtk_aal_stop,
};
static const struct mtk_ddp_comp_funcs ddp_gamma = {
+ .gamma_set = mtk_gamma_set,
.config = mtk_gamma_config,
.start = mtk_gamma_start,
.stop = mtk_gamma_stop,
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
index 6b13ba9..f4b7e0a 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
+++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
@@ -21,6 +21,7 @@ struct device_node;
struct drm_crtc;
struct drm_device;
struct mtk_plane_state;
+struct drm_crtc_state;
enum mtk_ddp_comp_type {
MTK_DISP_OVL,
@@ -73,6 +74,8 @@ struct mtk_ddp_comp_funcs {
void (*layer_off)(struct mtk_ddp_comp *comp, unsigned int idx);
void (*layer_config)(struct mtk_ddp_comp *comp, unsigned int idx,
struct mtk_plane_state *state);
+ void (*gamma_set)(struct mtk_ddp_comp *comp,
+ struct drm_crtc_state *state);
};
struct mtk_ddp_comp {
@@ -139,6 +142,13 @@ static inline void mtk_ddp_comp_layer_config(struct mtk_ddp_comp *comp,
comp->funcs->layer_config(comp, idx, state);
}
+static inline void mtk_ddp_gamma_set(struct mtk_ddp_comp *comp,
+ struct drm_crtc_state *state)
+{
+ if (comp->funcs && comp->funcs->gamma_set)
+ comp->funcs->gamma_set(comp, state);
+}
+
int mtk_ddp_comp_get_id(struct device_node *node,
enum mtk_ddp_comp_type comp_type);
int mtk_ddp_comp_init(struct device *dev, struct device_node *comp_node,
--
2.8.1
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