[PATCH 05/11] drm/rockchip: inno_hdmi: Add variant support

[Alex Bee <knaerzche@gmail.com>]

In preparation to support RK3128's integration of the controller, this
patch adds a simple variant implementation. They mainly differ in the
phy configuration required, so those are part of the match_data.
The values have been taken from downstream. The pixelclocks in there are
meant to be max-inclusive.

Signed-off-by: Alex Bee <knaerzche@gmail.com>
---
 drivers/gpu/drm/rockchip/inno_hdmi.c | 68 +++++++++++++++++++++++++++-
 1 file changed, 66 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/inno_hdmi.c b/drivers/gpu/drm/rockchip/inno_hdmi.c
index 32626a75723c..593b184bd0ad 100644
--- a/drivers/gpu/drm/rockchip/inno_hdmi.c
+++ b/drivers/gpu/drm/rockchip/inno_hdmi.c
@@ -27,6 +27,17 @@
 
 #include "inno_hdmi.h"
 
+struct inno_hdmi_phy_config {
+	unsigned int pixelclock;
+	u8 pre_emphasis;
+	u8 voltage_level_control;
+};
+
+struct inno_hdmi_variant {
+	struct inno_hdmi_phy_config *phy_configs;
+	struct inno_hdmi_phy_config *default_phy_config;
+};
+
 struct hdmi_data_info {
 	int vic;
 	bool sink_has_audio;
@@ -64,6 +75,14 @@ struct inno_hdmi {
 
 	struct hdmi_data_info	hdmi_data;
 	struct drm_display_mode previous_mode;
+
+	const struct inno_hdmi_variant *variant;
+};
+
+static struct inno_hdmi_phy_config rk3036_hdmi_phy_configs[] = {
+	{ 74250000,  0x3f, 0xbb },
+	{ 165000000, 0x6f, 0xbb },
+	{ ~0UL,	     0x00, 0x00 }
 };
 
 static struct inno_hdmi *encoder_to_inno_hdmi(struct drm_encoder *encoder)
@@ -176,6 +195,24 @@ static inline void hdmi_modb(struct inno_hdmi *hdmi, u16 offset,
 	hdmi_writeb(hdmi, offset, temp);
 }
 
+static int inno_hdmi_find_phy_config(struct inno_hdmi *hdmi,
+				     unsigned int pixelclk)
+{
+	const struct inno_hdmi_phy_config *phy_configs =
+						hdmi->variant->phy_configs;
+	int i;
+
+	for (i = 0; phy_configs[i].pixelclock != ~0UL; i++) {
+		if (pixelclk <= phy_configs[i].pixelclock)
+			return i;
+	}
+
+	DRM_DEV_DEBUG(hdmi->dev, "No phy configuration for pixelclock %u\n",
+		      pixelclk);
+
+	return -EINVAL;
+}
+
 static void inno_hdmi_i2c_init(struct inno_hdmi *hdmi)
 {
 	int ddc_bus_freq;
@@ -200,12 +237,25 @@ static void inno_hdmi_sys_power(struct inno_hdmi *hdmi, bool enable)
 
 static void inno_hdmi_set_pwr_mode(struct inno_hdmi *hdmi, int mode)
 {
+	int ret;
+	struct inno_hdmi_phy_config *phy_config;
+
 	switch (mode) {
 	case NORMAL:
 		inno_hdmi_sys_power(hdmi, false);
 
-		hdmi_writeb(hdmi, HDMI_PHY_PRE_EMPHASIS, 0x6f);
-		hdmi_writeb(hdmi, HDMI_PHY_DRIVER, 0xbb);
+		ret = inno_hdmi_find_phy_config(hdmi, hdmi->tmds_rate);
+		if (ret < 0) {
+			phy_config = hdmi->variant->default_phy_config;
+			DRM_DEV_ERROR(hdmi->dev,
+				      "Using default phy configuration for TMDS rate %u",
+				      hdmi->tmds_rate);
+		} else {
+			phy_config = &hdmi->variant->phy_configs[ret];
+		}
+
+		hdmi_writeb(hdmi, HDMI_PHY_PRE_EMPHASIS, phy_config->pre_emphasis);
+		hdmi_writeb(hdmi, HDMI_PHY_DRIVER, phy_config->voltage_level_control);
 
 		hdmi_writeb(hdmi, HDMI_PHY_SYS_CTL, 0x15);
 		hdmi_writeb(hdmi, HDMI_PHY_SYS_CTL, 0x14);
@@ -845,6 +895,8 @@ static int inno_hdmi_bind(struct device *dev, struct device *master,
 	struct platform_device *pdev = to_platform_device(dev);
 	struct drm_device *drm = data;
 	struct inno_hdmi *hdmi;
+	const struct inno_hdmi_variant *variant;
+
 	int irq;
 	int ret;
 
@@ -853,6 +905,12 @@ static int inno_hdmi_bind(struct device *dev, struct device *master,
 		return -ENOMEM;
 
 	hdmi->dev = dev;
+
+	variant = of_device_get_match_data(hdmi->dev);
+	if (!variant)
+		return -EINVAL;
+
+	hdmi->variant = variant;
 	hdmi->drm_dev = drm;
 
 	hdmi->regs = devm_platform_ioremap_resource(pdev, 0);
@@ -949,8 +1007,14 @@ static void inno_hdmi_remove(struct platform_device *pdev)
 	component_del(&pdev->dev, &inno_hdmi_ops);
 }
 
+static const struct inno_hdmi_variant rk3036_inno_hdmi_variant = {
+	.phy_configs = rk3036_hdmi_phy_configs,
+	.default_phy_config = &rk3036_hdmi_phy_configs[1],
+};
+
 static const struct of_device_id inno_hdmi_dt_ids[] = {
 	{ .compatible = "rockchip,rk3036-inno-hdmi",
+	  .data = &rk3036_inno_hdmi_variant,
 	},
 	{},
 };
-- 
2.43.0