[PATCH v2 4/6] drm/rockchip: inno-hdmi: Fix video timing HSYNC/VSYNC polarity setting for rk3036

From: Andy Yan
Date: Tue Mar 25 2025 - 09:43:14 EST


From: Andy Yan <andy.yan@xxxxxxxxxxxxxx>

The HSYNC/VSYNC polarity of rk3036 HDMI are controlled by GRF.
Without the polarity configuration in GRF, it can be observed
from the HDMI protocol analyzer that the H/V front/back timing
output by RK3036 HDMI are currently not in line with the specifications.

Signed-off-by: Andy Yan <andy.yan@xxxxxxxxxxxxxx>

---

Changes in v2:
- First included in this series

drivers/gpu/drm/rockchip/inno_hdmi.c | 36 +++++++++++++++++++++++++++-
1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/rockchip/inno_hdmi.c b/drivers/gpu/drm/rockchip/inno_hdmi.c
index e891d42dd08a4..db4b4038e51d5 100644
--- a/drivers/gpu/drm/rockchip/inno_hdmi.c
+++ b/drivers/gpu/drm/rockchip/inno_hdmi.c
@@ -10,10 +10,12 @@
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/hdmi.h>
+#include <linux/mfd/syscon.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
+#include <linux/regmap.h>

#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
@@ -29,8 +31,19 @@

#include "inno_hdmi.h"

+#define HIWORD_UPDATE(val, mask) ((val) | (mask) << 16)
+
#define INNO_HDMI_MIN_TMDS_CLOCK 25000000U

+#define RK3036_GRF_SOC_CON2 0x148
+#define RK3036_HDMI_PHSYNC BIT(4)
+#define RK3036_HDMI_PVSYNC BIT(5)
+
+enum inno_hdmi_dev_type {
+ RK3036_HDMI,
+ RK3128_HDMI,
+};
+
struct inno_hdmi_phy_config {
unsigned long pixelclock;
u8 pre_emphasis;
@@ -38,6 +51,7 @@ struct inno_hdmi_phy_config {
};

struct inno_hdmi_variant {
+ enum inno_hdmi_dev_type dev_type;
struct inno_hdmi_phy_config *phy_configs;
struct inno_hdmi_phy_config *default_phy_config;
};
@@ -58,6 +72,7 @@ struct inno_hdmi {
struct clk *pclk;
struct clk *refclk;
void __iomem *regs;
+ struct regmap *grf;

struct drm_connector connector;
struct rockchip_encoder encoder;
@@ -374,7 +389,15 @@ static int inno_hdmi_config_video_csc(struct inno_hdmi *hdmi)
static int inno_hdmi_config_video_timing(struct inno_hdmi *hdmi,
struct drm_display_mode *mode)
{
- int value;
+ int value, psync;
+
+ if (hdmi->variant->dev_type == RK3036_HDMI) {
+ psync = mode->flags & DRM_MODE_FLAG_PHSYNC ? RK3036_HDMI_PHSYNC : 0;
+ value = HIWORD_UPDATE(psync, RK3036_HDMI_PHSYNC);
+ psync = mode->flags & DRM_MODE_FLAG_PVSYNC ? RK3036_HDMI_PVSYNC : 0;
+ value |= HIWORD_UPDATE(psync, RK3036_HDMI_PVSYNC);
+ regmap_write(hdmi->grf, RK3036_GRF_SOC_CON2, value);
+ }

/* Set detail external video timing polarity and interlace mode */
value = v_EXTERANL_VIDEO(1);
@@ -904,6 +927,15 @@ static int inno_hdmi_bind(struct device *dev, struct device *master,
goto err_disable_pclk;
}

+ if (hdmi->variant->dev_type == RK3036_HDMI) {
+ hdmi->grf = syscon_regmap_lookup_by_phandle(dev->of_node, "rockchip,grf");
+ if (IS_ERR(hdmi->grf)) {
+ ret = dev_err_probe(dev, PTR_ERR(hdmi->grf),
+ "Unable to get rockchip,grf\n");
+ goto err_disable_clk;
+ }
+ }
+
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
ret = irq;
@@ -988,11 +1020,13 @@ static void inno_hdmi_remove(struct platform_device *pdev)
}

static const struct inno_hdmi_variant rk3036_inno_hdmi_variant = {
+ .dev_type = RK3036_HDMI,
.phy_configs = rk3036_hdmi_phy_configs,
.default_phy_config = &rk3036_hdmi_phy_configs[1],
};

static const struct inno_hdmi_variant rk3128_inno_hdmi_variant = {
+ .dev_type = RK3128_HDMI,
.phy_configs = rk3128_hdmi_phy_configs,
.default_phy_config = &rk3128_hdmi_phy_configs[1],
};
--
2.43.0