[PATCH 3/3] drm/bridge: Introduce LT9611 DSI to HDMI bridge

[Vinod Koul <vkoul@xxxxxxxxxx>]

Lontium Lt9611 is a DSI to HDMI bridge which supports two DSI ports and
I2S port as an input and HDMI port as output

Co-developed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
---
 drivers/gpu/drm/bridge/Kconfig  |   13 +
 drivers/gpu/drm/bridge/Makefile |    1 +
 drivers/gpu/drm/bridge/lt9611.c | 1113 +++++++++++++++++++++++++++++++
 3 files changed, 1127 insertions(+)
 create mode 100644 drivers/gpu/drm/bridge/lt9611.c

diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index aaed2347ace9..5cac15ce2027 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -38,6 +38,19 @@ config DRM_DISPLAY_CONNECTOR
 	  on ARM-based platforms. Saying Y here when this driver is not needed
 	  will not cause any issue.
 
+config DRM_LONTIUM_LT9611
+	tristate "Lontium LT9611 DSI/HDMI bridge"
+	select SND_SOC_HDMI_CODEC if SND_SOC
+	depends on OF
+	select DRM_PANEL_BRIDGE
+	select DRM_KMS_HELPER
+	select REGMAP_I2C
+	help
+	  Driver for Lontium LT9611 DSI to HDMI bridge
+	  chip driver that converts dual DSI and I2S to
+	  HDMI signals
+	  Please say Y if you have such hardware.
+
 config DRM_LVDS_CODEC
 	tristate "Transparent LVDS encoders and decoders support"
 	depends on OF
diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
index 6fb062b5b0f0..d2a696e8ca5d 100644
--- a/drivers/gpu/drm/bridge/Makefile
+++ b/drivers/gpu/drm/bridge/Makefile
@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_DRM_CDNS_DSI) += cdns-dsi.o
 obj-$(CONFIG_DRM_DISPLAY_CONNECTOR) += display-connector.o
+obj-$(CONFIG_DRM_LONTIUM_LT9611) += lt9611.o
 obj-$(CONFIG_DRM_LVDS_CODEC) += lvds-codec.o
 obj-$(CONFIG_DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW) += megachips-stdpxxxx-ge-b850v3-fw.o
 obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o
diff --git a/drivers/gpu/drm/bridge/lt9611.c b/drivers/gpu/drm/bridge/lt9611.c
new file mode 100644
index 000000000000..e6e7ce43980d
--- /dev/null
+++ b/drivers/gpu/drm/bridge/lt9611.c
@@ -0,0 +1,1113 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2019-2020. Linaro Limited.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/interrupt.h>
+#include <linux/of_graph.h>
+#include <linux/regulator/consumer.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_bridge.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_print.h>
+
+#define EDID_SEG_SIZE 256
+
+#define LT9611_4LANES	0
+
+struct lt9611 {
+	struct device *dev;
+	struct drm_bridge bridge;
+	struct drm_connector connector;
+
+	struct regmap *regmap;
+
+	struct device_node *dsi0_node;
+	struct device_node *dsi1_node;
+	struct mipi_dsi_device *dsi0;
+	struct mipi_dsi_device *dsi1;
+
+	bool ac_mode;
+
+	struct gpio_desc *reset_gpio;
+	struct gpio_desc *enable_gpio;
+
+	bool power_on;
+	bool sleep;
+
+	struct regulator_bulk_data supplies[2];
+
+	struct i2c_client *client;
+
+	enum drm_connector_status status;
+
+	u8 edid_buf[EDID_SEG_SIZE];
+	u32 vic;
+};
+
+#define LT9611_PAGE_CONTROL	0xff
+
+static const struct regmap_range_cfg lt9611_ranges[] = {
+	{
+		.name = "register_range",
+		.range_min =  0,
+		.range_max = 0x85ff,
+		.selector_reg = LT9611_PAGE_CONTROL,
+		.selector_mask = 0xff,
+		.selector_shift = 0,
+		.window_start = 0,
+		.window_len = 0x100,
+	},
+};
+
+static const struct regmap_config lt9611_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = 0xffff,
+	.ranges = lt9611_ranges,
+	.num_ranges = ARRAY_SIZE(lt9611_ranges),
+};
+
+struct lt9611_mode {
+	u16 hdisplay;
+	u16 vdisplay;
+	u8 fps;
+	u8 lanes;
+	u8 intfs;
+};
+
+static struct lt9611_mode lt9611_modes[] = {
+	{ 3840, 2160, 30, 4, 2 }, /* 3840x2160 24bit 30Hz 4Lane 2ports */
+	{ 1920, 1080, 60, 4, 1 }, /* 1080P 24bit 60Hz 4lane 1port */
+	{ 1920, 1080, 30, 3, 1 }, /* 1080P 24bit 30Hz 3lane 1port */
+	{ 1920, 1080, 24, 3, 1 },
+	{ 720, 480, 60, 4, 1 },
+	{ 720, 576, 50, 2, 1 },
+	{ 640, 480, 60, 2, 1 },
+};
+
+static struct lt9611 *bridge_to_lt9611(struct drm_bridge *bridge)
+{
+	return container_of(bridge, struct lt9611, bridge);
+}
+
+static struct lt9611 *connector_to_lt9611(struct drm_connector *connector)
+{
+	return container_of(connector, struct lt9611, connector);
+}
+
+static int lt9611_mipi_input_analog(struct lt9611 *lt9611)
+{
+	struct reg_sequence reg_cfg[] = {
+		{ 0x8106, 0x40 }, /*port A rx current*/
+		{ 0x810a, 0xfe }, /*port A ldo voltage set*/
+		{ 0x810b, 0xbf }, /*enable port A lprx*/
+		{ 0x8111, 0x40 }, /*port B rx current*/
+		{ 0x8115, 0xfe }, /*port B ldo voltage set*/
+		{ 0x8116, 0xbf }, /*enable port B lprx*/
+
+		{ 0x811c, 0x03 }, /*PortA clk lane no-LP mode*/
+		{ 0x8120, 0x03 }, /*PortB clk lane with-LP mode*/
+	};
+
+	regmap_multi_reg_write(lt9611->regmap, reg_cfg, ARRAY_SIZE(reg_cfg));
+
+	return 0;
+}
+
+static int lt9611_mipi_input_digital(struct lt9611 *lt9611,
+				     const struct drm_display_mode *mode)
+{
+	regmap_write(lt9611->regmap, 0x8300, LT9611_4LANES);
+
+	if (mode->hdisplay == 3840)
+		regmap_write(lt9611->regmap, 0x830a, 0x03);
+	else
+		regmap_write(lt9611->regmap, 0x830a, 0x00);
+
+	regmap_write(lt9611->regmap, 0x824f, 0x80);
+	regmap_write(lt9611->regmap, 0x8250, 0x10);
+	regmap_write(lt9611->regmap, 0x8302, 0x0a);
+	regmap_write(lt9611->regmap, 0x8306, 0x0a);
+
+	return 0;
+}
+
+static void lt9611_mipi_video_setup(struct lt9611 *lt9611,
+				    const struct drm_display_mode *mode)
+{
+	u32 h_total, h_act, hpw, hfp, hss;
+	u32 v_total, v_act, vpw, vfp, vss;
+
+	h_total = mode->htotal;
+	v_total = mode->vtotal;
+
+	h_act = mode->hdisplay;
+	hpw = mode->hsync_end - mode->hsync_start;
+	hfp = mode->hsync_start - mode->hdisplay;
+	hss = (mode->hsync_end - mode->hsync_start) +
+	      (mode->htotal - mode->hsync_end);
+
+	v_act = mode->vdisplay;
+	vpw = mode->vsync_end - mode->vsync_start;
+	vfp = mode->vsync_start - mode->vdisplay;
+	vss = (mode->vsync_end - mode->vsync_start) +
+	      (mode->vtotal - mode->vsync_end);
+
+	regmap_write(lt9611->regmap, 0x830d, (u8)(v_total / 256));
+	regmap_write(lt9611->regmap, 0x830e, (u8)(v_total % 256));
+
+	regmap_write(lt9611->regmap, 0x830f, (u8)(v_act / 256));
+	regmap_write(lt9611->regmap, 0x8310, (u8)(v_act % 256));
+
+	regmap_write(lt9611->regmap, 0x8311, (u8)(h_total / 256));
+	regmap_write(lt9611->regmap, 0x8312, (u8)(h_total % 256));
+
+	regmap_write(lt9611->regmap, 0x8313, (u8)(h_act / 256));
+	regmap_write(lt9611->regmap, 0x8314, (u8)(h_act % 256));
+
+	regmap_write(lt9611->regmap, 0x8315, (u8)(vpw % 256));
+	regmap_write(lt9611->regmap, 0x8316, (u8)(hpw % 256));
+
+	regmap_write(lt9611->regmap, 0x8317, (u8)(vfp % 256));
+
+	regmap_write(lt9611->regmap, 0x8318, (u8)(vss % 256));
+
+	regmap_write(lt9611->regmap, 0x8319, (u8)(hfp % 256));
+
+	regmap_write(lt9611->regmap, 0x831a, (u8)(hss / 256));
+	regmap_write(lt9611->regmap, 0x831b, (u8)(hss % 256));
+}
+
+static int lt9611_pcr_setup(struct lt9611 *lt9611,
+			    const struct drm_display_mode *mode)
+{
+	struct reg_sequence reg_cfg[] = {
+		{ 0x830b, 0x01 },
+		{ 0x830c, 0x10 },
+		{ 0x8348, 0x00 },
+		{ 0x8349, 0x81 },
+
+		/* stage 1 */
+		{ 0x8321, 0x4a },
+		{ 0x8324, 0x71 },
+		{ 0x8325, 0x30 },
+		{ 0x832a, 0x01 },
+
+		/* stage 2 */
+		{ 0x834a, 0x40 },
+		{ 0x831d, 0x10 },
+
+		/* MK limit */
+		{ 0x832d, 0x38 },
+		{ 0x8331, 0x08 },
+	};
+
+	regmap_multi_reg_write(lt9611->regmap, reg_cfg, ARRAY_SIZE(reg_cfg));
+
+	switch (mode->hdisplay) {
+	case 640:
+		regmap_write(lt9611->regmap, 0x8326, 0x14);
+		break;
+	case 1920:
+		regmap_write(lt9611->regmap, 0x8326, 0x37);
+		break;
+	case 3840:
+		regmap_write(lt9611->regmap, 0x830b, 0x03);
+		regmap_write(lt9611->regmap, 0x830c, 0xd0);
+		regmap_write(lt9611->regmap, 0x8348, 0x03);
+		regmap_write(lt9611->regmap, 0x8349, 0xe0);
+		regmap_write(lt9611->regmap, 0x8324, 0x72);
+		regmap_write(lt9611->regmap, 0x8325, 0x00);
+		regmap_write(lt9611->regmap, 0x832a, 0x01);
+		regmap_write(lt9611->regmap, 0x834a, 0x10);
+		regmap_write(lt9611->regmap, 0x831d, 0x10);
+		regmap_write(lt9611->regmap, 0x8326, 0x37);
+		break;
+	}
+
+	/* pcr rst */
+	regmap_write(lt9611->regmap, 0x8011, 0x5a);
+	regmap_write(lt9611->regmap, 0x8011, 0xfa);
+
+	return 0;
+}
+
+static int lt9611_pll_setup(struct lt9611 *lt9611,
+			    const struct drm_display_mode *mode)
+{
+	unsigned int pclk = mode->clock;
+	struct reg_sequence reg_cfg[] = {
+		/* txpll init */
+		{ 0x8123, 0x40 },
+		{ 0x8124, 0x64 },
+		{ 0x8125, 0x80 },
+		{ 0x8126, 0x55 },
+		{ 0x812c, 0x37 },
+		{ 0x812f, 0x01 },
+		{ 0x8126, 0x55 },
+		{ 0x8127, 0x66 },
+		{ 0x8128, 0x88 },
+	};
+
+	regmap_multi_reg_write(lt9611->regmap, reg_cfg, ARRAY_SIZE(reg_cfg));
+
+	if (pclk > 150000)
+		regmap_write(lt9611->regmap, 0x812d, 0x88);
+	else if (pclk > 70000)
+		regmap_write(lt9611->regmap, 0x812d, 0x99);
+	else
+		regmap_write(lt9611->regmap, 0x812d, 0xaa);
+
+	regmap_write(lt9611->regmap, 0x82e3, pclk >> 17); /* pclk[19:16] */
+	regmap_write(lt9611->regmap, 0x82e4, pclk >> 9);  /* pclk[15:8]  */
+	regmap_write(lt9611->regmap, 0x82e5, pclk >> 1);  /* pclk[7:0]   */
+
+	regmap_write(lt9611->regmap, 0x82de, 0x20);
+	regmap_write(lt9611->regmap, 0x82de, 0xe0);
+
+	regmap_write(lt9611->regmap, 0x8016, 0xf1);
+	regmap_write(lt9611->regmap, 0x8016, 0xf3);
+
+	return 0;
+}
+
+static int lt9611_video_check(struct lt9611 *lt9611)
+{
+	u32 v_total, v_act, h_act_a, h_act_b, h_total_sysclk;
+	unsigned int temp;
+	int ret;
+
+	/* top module video check */
+
+	/* v_act */
+	ret = regmap_read(lt9611->regmap, 0x8282, &temp);
+	if (ret)
+		goto end;
+
+	v_act = temp << 8;
+	ret = regmap_read(lt9611->regmap, 0x8283, &temp);
+	if (ret)
+		goto end;
+	v_act = v_act + temp;
+
+	/* v_total */
+	ret = regmap_read(lt9611->regmap, 0x826c, &temp);
+	if (ret)
+		goto end;
+	v_total = temp << 8;
+	ret = regmap_read(lt9611->regmap, 0x826d, &temp);
+	if (ret)
+		goto end;
+	v_total = v_total + temp;
+
+	/* h_total_sysclk */
+	ret = regmap_read(lt9611->regmap, 0x8286, &temp);
+	if (ret)
+		goto end;
+	h_total_sysclk = temp << 8;
+	ret = regmap_read(lt9611->regmap, 0x8287, &temp);
+	if (ret)
+		goto end;
+	h_total_sysclk = h_total_sysclk + temp;
+
+	/* h_act_a */
+	ret = regmap_read(lt9611->regmap, 0x8382, &temp);
+	if (ret)
+		goto end;
+	h_act_a = temp << 8;
+	ret = regmap_read(lt9611->regmap, 0x8383, &temp);
+	if (ret)
+		goto end;
+	h_act_a = (h_act_a + temp) / 3;
+
+	/* h_act_b */
+	ret = regmap_read(lt9611->regmap, 0x8386, &temp);
+	if (ret)
+		goto end;
+	h_act_b = temp << 8;
+	ret = regmap_read(lt9611->regmap, 0x8387, &temp);
+	if (ret)
+		goto end;
+	h_act_b = (h_act_b + temp) / 3;
+
+	dev_info(lt9611->dev,
+		 "video check: h_act_a=%d, h_act_b=%d, v_act=%d, v_total=%d, h_total_sysclk=%d\n",
+		 h_act_a, h_act_b, v_act, v_total, h_total_sysclk);
+
+	return 0;
+
+end:
+	dev_err(lt9611->dev, "read video check error\n");
+	return ret;
+}
+
+static void lt9611_hdmi_tx_digital(struct lt9611 *lt9611)
+{
+	regmap_write(lt9611->regmap, 0x8443, 0x46 - lt9611->vic);
+	regmap_write(lt9611->regmap, 0x8447, lt9611->vic);
+	regmap_write(lt9611->regmap, 0x843d, 0x0a); /* UD1 infoframe */
+
+	regmap_write(lt9611->regmap, 0x82d6, 0x8c);
+	regmap_write(lt9611->regmap, 0x82d7, 0x04);
+}
+
+static void lt9611_hdmi_tx_phy(struct lt9611 *lt9611)
+{
+	struct reg_sequence reg_cfg[] = {
+		{ 0x8130, 0x6a },
+		{ 0x8131, 0x44 }, /* HDMI DC mode */
+		{ 0x8132, 0x4a },
+		{ 0x8133, 0x0b },
+		{ 0x8134, 0x00 },
+		{ 0x8135, 0x00 },
+		{ 0x8136, 0x00 },
+		{ 0x8137, 0x44 },
+		{ 0x813f, 0x0f },
+		{ 0x8140, 0xa0 },
+		{ 0x8141, 0xa0 },
+		{ 0x8142, 0xa0 },
+		{ 0x8143, 0xa0 },
+		{ 0x8144, 0x0a },
+	};
+
+	/* HDMI AC mode */
+	if (lt9611->ac_mode)
+		reg_cfg[2].def = 0x73;
+
+	regmap_multi_reg_write(lt9611->regmap, reg_cfg, ARRAY_SIZE(reg_cfg));
+}
+
+static irqreturn_t lt9611_irq_thread_handler(int irq, void *dev_id)
+{
+	struct lt9611 *lt9611 = dev_id;
+	unsigned int irq_flag0 = 0;
+	unsigned int irq_flag3 = 0;
+
+	regmap_read(lt9611->regmap, 0x820f, &irq_flag3);
+	regmap_read(lt9611->regmap, 0x820c, &irq_flag0);
+
+	pr_debug("%s() irq_flag0: %#x irq_flag3: %#x\n",
+		 __func__, irq_flag0, irq_flag3);
+
+	 /* hpd changed low */
+	if (irq_flag3 & 0x80) {
+		dev_info(lt9611->dev, "hdmi cable disconnected\n");
+
+		regmap_write(lt9611->regmap, 0x8207, 0xbf);
+		regmap_write(lt9611->regmap, 0x8207, 0x3f);
+	}
+	 /* hpd changed high */
+	if (irq_flag3 & 0x40) {
+		dev_info(lt9611->dev, "hdmi cable connected\n");
+
+		regmap_write(lt9611->regmap, 0x8207, 0x7f);
+		regmap_write(lt9611->regmap, 0x8207, 0x3f);
+	}
+
+	if (irq_flag3 & 0xc0)
+		drm_kms_helper_hotplug_event(lt9611->bridge.dev);
+
+	/* video input changed */
+	if (irq_flag0 & 0x01) {
+		dev_info(lt9611->dev, "video input changed\n");
+		regmap_write(lt9611->regmap, 0x829e, 0xff);
+		regmap_write(lt9611->regmap, 0x829e, 0xf7);
+		regmap_write(lt9611->regmap, 0x8204, 0xff);
+		regmap_write(lt9611->regmap, 0x8204, 0xfe);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static void lt9611_enable_hpd_interrupts(struct lt9611 *lt9611)
+{
+	unsigned int val;
+
+	dev_dbg(lt9611->dev, "enabling hpd interrupts\n");
+
+	regmap_read(lt9611->regmap, 0x8203, &val);
+
+	val &= ~0xc0;
+	regmap_write(lt9611->regmap, 0x8203, val);
+	regmap_write(lt9611->regmap, 0x8207, 0xff); //clear
+	regmap_write(lt9611->regmap, 0x8207, 0x3f);
+}
+
+static void lt9611_sleep_setup(struct lt9611 *lt9611)
+{
+	struct reg_sequence sleep_setup[] = {
+		{ 0x8024, 0x76 },
+		{ 0x8023, 0x01 },
+		{ 0x8157, 0x03 }, //set addr pin as output
+		{ 0x8149, 0x0b },
+		{ 0x8151, 0x30 }, //disable IRQ
+		{ 0x8102, 0x48 }, //MIPI Rx power down
+		{ 0x8123, 0x80 },
+		{ 0x8130, 0x00 },
+		{ 0x8100, 0x01 }, //bandgap power down
+		{ 0x8101, 0x00 }, //system clk power down
+	};
+
+	dev_dbg(lt9611->dev, "sleep\n");
+
+	regmap_multi_reg_write(lt9611->regmap,
+			       sleep_setup, ARRAY_SIZE(sleep_setup));
+	lt9611->sleep = true;
+}
+
+static int lt9611_power_on(struct lt9611 *lt9611)
+{
+	int ret;
+	const struct reg_sequence seq[] = {
+		/* LT9611_System_Init */
+		{ 0x8101, 0x18 }, /* sel xtal clock */
+
+		/* timer for frequency meter */
+		{ 0x821b, 0x69 }, /*timer 2*/
+		{ 0x821c, 0x78 },
+		{ 0x82cb, 0x69 }, /*timer 1 */
+		{ 0x82cc, 0x78 },
+
+		/* irq init */
+		{ 0x8251, 0x01 },
+		{ 0x8258, 0x0a }, /* hpd irq */
+		{ 0x8259, 0x80 }, /* hpd debounce width */
+		{ 0x829e, 0xf7 }, /* video check irq */
+
+		/* power consumption for work */
+		{ 0x8004, 0xf0 },
+		{ 0x8006, 0xf0 },
+		{ 0x800a, 0x80 },
+		{ 0x800b, 0x40 },
+		{ 0x800d, 0xef },
+		{ 0x8011, 0xfa },
+	};
+
+	if (lt9611->power_on)
+		return 0;
+
+	dev_dbg(lt9611->dev, "power on\n");
+
+	ret = regmap_multi_reg_write(lt9611->regmap, seq, ARRAY_SIZE(seq));
+	if (!ret)
+		lt9611->power_on = true;
+
+	return ret;
+}
+
+static int lt9611_power_off(struct lt9611 *lt9611)
+{
+	int ret;
+
+	dev_dbg(lt9611->dev, "power off\n");
+
+	ret = regmap_write(lt9611->regmap, 0x8130, 0x6a);
+	if (!ret)
+		lt9611->power_on = false;
+
+	return ret;
+}
+
+static void lt9611_reset(struct lt9611 *lt9611)
+{
+	gpiod_set_value_cansleep(lt9611->reset_gpio, 1);
+	msleep(20);
+	gpiod_set_value_cansleep(lt9611->reset_gpio, 0);
+	msleep(20);
+	gpiod_set_value_cansleep(lt9611->reset_gpio, 1);
+	msleep(100);
+}
+
+static void lt9611_assert_5v(struct lt9611 *lt9611)
+{
+	if (!lt9611->enable_gpio)
+		return;
+
+	gpiod_set_value_cansleep(lt9611->enable_gpio, 1);
+	msleep(20);
+}
+
+static int lt9611_regulator_init(struct lt9611 *lt9611)
+{
+	int ret;
+
+	lt9611->supplies[0].supply = "vdd";
+	lt9611->supplies[1].supply = "vcc";
+	ret = devm_regulator_bulk_get(lt9611->dev, 2, lt9611->supplies);
+	if (ret < 0)
+		return ret;
+
+	return regulator_set_load(lt9611->supplies[0].consumer, 300000);
+}
+
+static int lt9611_regulator_enable(struct lt9611 *lt9611)
+{
+	int ret;
+
+	ret = regulator_enable(lt9611->supplies[0].consumer);
+	if (ret < 0)
+		return ret;
+
+	usleep_range(1000, 10000);
+
+	ret = regulator_enable(lt9611->supplies[1].consumer);
+	if (ret < 0) {
+		regulator_disable(lt9611->supplies[0].consumer);
+		return ret;
+	}
+
+	return 0;
+}
+
+static struct lt9611_mode *lt9611_find_mode(const struct drm_display_mode *mode)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(lt9611_modes); i++) {
+		if (lt9611_modes[i].hdisplay == mode->hdisplay &&
+		    lt9611_modes[i].vdisplay == mode->vdisplay &&
+		    lt9611_modes[i].fps == drm_mode_vrefresh(mode)) {
+			return &lt9611_modes[i];
+		}
+	}
+
+	return NULL;
+}
+
+/* connector funcs */
+static enum drm_connector_status
+lt9611_connector_detect(struct drm_connector *connector, bool force)
+{
+	struct lt9611 *lt9611 = connector_to_lt9611(connector);
+	unsigned int reg_val = 0;
+	int connected = 0;
+
+	regmap_read(lt9611->regmap, 0x825e, &reg_val);
+	connected  = (reg_val & BIT(2));
+	dev_dbg(lt9611->dev, "connected = %x\n", connected);
+
+	lt9611->status = connected ?  connector_status_connected :
+				connector_status_disconnected;
+
+	return lt9611->status;
+}
+
+static int lt9611_read_edid(struct lt9611 *lt9611)
+{
+	unsigned int temp;
+	int ret = 0;
+	int i, j;
+
+	memset(lt9611->edid_buf, 0, EDID_SEG_SIZE);
+
+	regmap_write(lt9611->regmap, 0x8503, 0xc9);
+
+	/* 0xA0 is EDID device address */
+	regmap_write(lt9611->regmap, 0x8504, 0xa0);
+	/* 0x00 is EDID offset address */
+	regmap_write(lt9611->regmap, 0x8505, 0x00);
+	/* length for read */
+	regmap_write(lt9611->regmap, 0x8506, 0x20);
+	regmap_write(lt9611->regmap, 0x8514, 0x7f);
+
+	for (i = 0 ; i < 8 ; i++) {
+		/* offset address */
+		regmap_write(lt9611->regmap, 0x8505, i * 32);
+		regmap_write(lt9611->regmap, 0x8507, 0x36);
+		regmap_write(lt9611->regmap, 0x8507, 0x31);
+		regmap_write(lt9611->regmap, 0x8507, 0x37);
+		usleep_range(5000, 10000);
+
+		regmap_read(lt9611->regmap, 0x8540, &temp);
+
+		if (temp & 0x02) {  /*KEY_DDC_ACCS_DONE=1*/
+			for (j = 0; j < 32; j++) {
+				regmap_read(lt9611->regmap, 0x8583, &temp);
+				lt9611->edid_buf[i * 32 + j] = temp;
+			}
+		} else if (temp & 0x50) { /* DDC No Ack or Abitration lost */
+			dev_err(lt9611->dev, "read edid failed: no ack\n");
+			ret = -EIO;
+			goto end;
+		} else {
+			dev_err(lt9611->dev,
+				"read edid failed: access not done\n");
+			ret = -EIO;
+			goto end;
+		}
+	}
+
+	dev_dbg(lt9611->dev, "read edid succeeded, checksum = 0x%x\n",
+		lt9611->edid_buf[255]);
+
+end:
+	regmap_write(lt9611->regmap, 0x8507, 0x1f);
+	return ret;
+}
+
+/* TODO: add support for more extension blocks */
+static int
+lt9611_get_edid_block(void *data, u8 *buf, unsigned int block, size_t len)
+{
+	struct lt9611 *lt9611 = data;
+	int ret;
+
+	dev_dbg(lt9611->dev, "get edid block: block=%d, len=%d\n",
+		block, (int)len);
+
+	if (len > 128)
+		return -EINVAL;
+
+	/* support up to 1 extension block */
+	if (block > 1)
+		return -EINVAL;
+
+	if (block == 0) {
+		/* always read 2 edid blocks once */
+		ret = lt9611_read_edid(lt9611);
+		if (ret) {
+			dev_err(lt9611->dev, "edid read failed\n");
+			return ret;
+		}
+	}
+
+	if (block % 2 == 0)
+		memcpy(buf, lt9611->edid_buf, len);
+	else
+		memcpy(buf, lt9611->edid_buf + 128, len);
+
+	return 0;
+}
+
+static int lt9611_connector_get_modes(struct drm_connector *connector)
+{
+	struct lt9611 *lt9611 = connector_to_lt9611(connector);
+	unsigned int count;
+	struct edid *edid;
+
+	dev_dbg(lt9611->dev, "get modes\n");
+
+	lt9611_power_on(lt9611);
+	edid = drm_do_get_edid(connector, lt9611_get_edid_block, lt9611);
+	drm_connector_update_edid_property(connector, edid);
+	count = drm_add_edid_modes(connector, edid);
+	kfree(edid);
+
+	return count;
+}
+
+static enum drm_mode_status
+lt9611_connector_mode_valid(struct drm_connector *connector,
+			    struct drm_display_mode *mode)
+{
+	struct lt9611_mode *lt9611_mode = lt9611_find_mode(mode);
+
+	return lt9611_mode ? MODE_OK : MODE_BAD;
+}
+
+/* bridge funcs */
+static void lt9611_bridge_enable(struct drm_bridge *bridge)
+{
+	struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
+
+	dev_dbg(lt9611->dev, "bridge enable\n");
+
+	if (lt9611_power_on(lt9611)) {
+		dev_err(lt9611->dev, "power on failed\n");
+		return;
+	}
+
+	dev_dbg(lt9611->dev, "video on\n");
+
+	lt9611_mipi_input_analog(lt9611);
+	lt9611_hdmi_tx_digital(lt9611);
+	lt9611_hdmi_tx_phy(lt9611);
+
+	msleep(500);
+
+	lt9611_video_check(lt9611);
+
+	/* Enable HDMI output */
+	regmap_write(lt9611->regmap, 0x8130, 0xea);
+}
+
+static void lt9611_bridge_disable(struct drm_bridge *bridge)
+{
+	struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
+	int ret;
+
+	dev_dbg(lt9611->dev, "bridge disable\n");
+
+	/* Disable HDMI output */
+	ret = regmap_write(lt9611->regmap, 0x8130, 0x6a);
+	if (ret) {
+		dev_err(lt9611->dev, "video on failed\n");
+		return;
+	}
+
+	if (lt9611_power_off(lt9611)) {
+		dev_err(lt9611->dev, "power on failed\n");
+		return;
+	}
+}
+
+static struct
+drm_connector_helper_funcs lt9611_bridge_connector_helper_funcs = {
+	.get_modes = lt9611_connector_get_modes,
+	.mode_valid = lt9611_connector_mode_valid,
+};
+
+static const struct drm_connector_funcs lt9611_bridge_connector_funcs = {
+	.fill_modes = drm_helper_probe_single_connector_modes,
+	.detect = lt9611_connector_detect,
+	.destroy = drm_connector_cleanup,
+	.reset = drm_atomic_helper_connector_reset,
+	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
+	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static struct mipi_dsi_device *lt9611_attach_dsi(struct lt9611 *lt9611,
+						 struct device_node *dsi_node)
+{
+	const struct mipi_dsi_device_info info = { "lt9611", 0, NULL };
+	struct mipi_dsi_device *dsi;
+	struct mipi_dsi_host *host;
+	int ret;
+
+	host = of_find_mipi_dsi_host_by_node(dsi_node);
+	if (!host) {
+		dev_err(lt9611->dev, "failed to find dsi host\n");
+		return ERR_PTR(-EPROBE_DEFER);
+	}
+
+	dsi = mipi_dsi_device_register_full(host, &info);
+	if (IS_ERR(dsi)) {
+		dev_err(lt9611->dev, "failed to create dsi device\n");
+		return dsi;
+	}
+
+	dsi->lanes = 4;
+	dsi->format = MIPI_DSI_FMT_RGB888;
+	dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_SYNC_PULSE |
+			  MIPI_DSI_MODE_VIDEO_HSE;
+
+	ret = mipi_dsi_attach(dsi);
+	if (ret < 0) {
+		dev_err(lt9611->dev, "failed to attach dsi to host\n");
+		mipi_dsi_device_unregister(dsi);
+		return ERR_PTR(ret);
+	}
+
+	return dsi;
+}
+
+static int lt9611_bridge_attach(struct drm_bridge *bridge,
+				enum drm_bridge_attach_flags flags)
+{
+	struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
+	int ret;
+
+	dev_dbg(lt9611->dev, "bridge attach\n");
+
+	ret = drm_connector_init(bridge->dev, &lt9611->connector,
+				 &lt9611_bridge_connector_funcs,
+				 DRM_MODE_CONNECTOR_HDMIA);
+	if (ret) {
+		DRM_ERROR("Failed to initialize connector with drm\n");
+		return ret;
+	}
+
+	drm_connector_helper_add(&lt9611->connector,
+				 &lt9611_bridge_connector_helper_funcs);
+	drm_connector_attach_encoder(&lt9611->connector, bridge->encoder);
+
+	if (!bridge->encoder) {
+		DRM_ERROR("Parent encoder object not found");
+		return -ENODEV;
+	}
+
+	/* Attach primary DSI */
+	lt9611->dsi0 = lt9611_attach_dsi(lt9611, lt9611->dsi0_node);
+	if (IS_ERR(lt9611->dsi0))
+		return PTR_ERR(lt9611->dsi0);
+
+	/* Attach secondary DSI, if specified */
+	if (lt9611->dsi1_node) {
+		lt9611->dsi1 = lt9611_attach_dsi(lt9611, lt9611->dsi1_node);
+		if (IS_ERR(lt9611->dsi1)) {
+			ret = PTR_ERR(lt9611->dsi1);
+			goto err_unregister_dsi0;
+		}
+	}
+
+	return 0;
+
+err_unregister_dsi0:
+	mipi_dsi_device_unregister(lt9611->dsi0);
+
+	return ret;
+}
+
+static void lt9611_bridge_detach(struct drm_bridge *bridge)
+{
+	struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
+
+	if (lt9611->dsi1) {
+		mipi_dsi_detach(lt9611->dsi1);
+		mipi_dsi_device_unregister(lt9611->dsi1);
+	}
+
+	mipi_dsi_detach(lt9611->dsi0);
+	mipi_dsi_device_unregister(lt9611->dsi0);
+}
+
+static enum drm_mode_status
+lt9611_bridge_mode_valid(struct drm_bridge *bridge,
+			 const struct drm_display_mode *mode)
+{
+	struct lt9611_mode *lt9611_mode = lt9611_find_mode(mode);
+	struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
+
+	if (lt9611_mode->intfs > 1 && !lt9611->dsi1)
+		return MODE_PANEL;
+	else
+		return MODE_OK;
+}
+
+static void lt9611_bridge_pre_enable(struct drm_bridge *bridge)
+{
+	struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
+
+	dev_dbg(lt9611->dev, "bridge pre_enable\n");
+
+	if (!lt9611->sleep)
+		return;
+
+	lt9611_reset(lt9611);
+	regmap_write(lt9611->regmap, 0x80ee, 0x01);
+
+	lt9611->sleep = false;
+}
+
+static void lt9611_bridge_post_disable(struct drm_bridge *bridge)
+{
+	struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
+
+	dev_dbg(lt9611->dev, "bridge post_disable\n");
+
+	lt9611_sleep_setup(lt9611);
+}
+
+static void lt9611_bridge_mode_set(struct drm_bridge *bridge,
+				   const struct drm_display_mode *mode,
+				   const struct drm_display_mode *adj_mode)
+{
+	struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
+	struct hdmi_avi_infoframe avi_frame;
+	int ret;
+
+	dev_dbg(lt9611->dev, "bridge mode_set: hdisplay=%d, vdisplay=%d, vrefresh=%d, clock=%d\n",
+		adj_mode->hdisplay, adj_mode->vdisplay,
+		adj_mode->vrefresh, adj_mode->clock);
+
+	lt9611_bridge_pre_enable(bridge);
+
+	lt9611_mipi_input_digital(lt9611, mode);
+	lt9611_pll_setup(lt9611, mode);
+	lt9611_mipi_video_setup(lt9611, mode);
+	lt9611_pcr_setup(lt9611, mode);
+
+	ret = drm_hdmi_avi_infoframe_from_display_mode(&avi_frame,
+						       &lt9611->connector,
+						       mode);
+	if (!ret)
+		lt9611->vic = avi_frame.video_code;
+}
+
+static const struct drm_bridge_funcs lt9611_bridge_funcs = {
+	.attach = lt9611_bridge_attach,
+	.detach = lt9611_bridge_detach,
+	.mode_valid = lt9611_bridge_mode_valid,
+	.enable = lt9611_bridge_enable,
+	.disable = lt9611_bridge_disable,
+	.post_disable = lt9611_bridge_post_disable,
+	.mode_set = lt9611_bridge_mode_set,
+};
+
+static int lt9611_parse_dt(struct device *dev,
+			   struct lt9611 *lt9611)
+{
+	lt9611->dsi0_node = of_graph_get_remote_node(dev->of_node, 1, -1);
+	if (!lt9611->dsi0_node) {
+		DRM_DEV_ERROR(dev, "failed to get remote node for primary dsi\n");
+		return -ENODEV;
+	}
+
+	lt9611->dsi1_node = of_graph_get_remote_node(dev->of_node, 2, -1);
+
+	lt9611->ac_mode = of_property_read_bool(dev->of_node, "lt,ac-mode");
+	dev_dbg(lt9611->dev, "ac_mode=%d\n", lt9611->ac_mode);
+
+	return 0;
+}
+
+static int lt9611_gpio_init(struct lt9611 *lt9611)
+{
+	struct device *dev = lt9611->dev;
+
+	lt9611->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(lt9611->reset_gpio)) {
+		dev_err(dev, "failed to acquire reset gpio\n");
+		return PTR_ERR(lt9611->reset_gpio);
+	}
+
+	lt9611->enable_gpio = devm_gpiod_get_optional(dev, "enable",
+						      GPIOD_OUT_LOW);
+	if (IS_ERR(lt9611->enable_gpio)) {
+		dev_err(dev, "failed to acquire enable gpio\n");
+		return PTR_ERR(lt9611->enable_gpio);
+	}
+
+	return 0;
+}
+
+static int lt9611_read_device_rev(struct lt9611 *lt9611)
+{
+	unsigned int rev;
+	int ret;
+
+	regmap_write(lt9611->regmap, 0x80ee, 0x01);
+	ret = regmap_read(lt9611->regmap, 0x8002, &rev);
+	if (ret)
+		dev_err(lt9611->dev, "failed to read revision: %d\n", ret);
+
+	dev_info(lt9611->dev, "LT9611 revision: 0x%x\n", rev);
+
+	return ret;
+}
+
+static int lt9611_probe(struct i2c_client *client,
+			const struct i2c_device_id *id)
+{
+	struct lt9611 *lt9611;
+	struct device *dev = &client->dev;
+	int ret;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+		dev_err(dev, "device doesn't support I2C\n");
+		return -ENODEV;
+	}
+
+	lt9611 = devm_kzalloc(dev, sizeof(*lt9611), GFP_KERNEL);
+	if (!lt9611)
+		return -ENOMEM;
+
+	lt9611->dev = &client->dev;
+	lt9611->client = client;
+	lt9611->sleep = false;
+
+	lt9611->regmap = devm_regmap_init_i2c(client, &lt9611_regmap_config);
+	if (IS_ERR(lt9611->regmap)) {
+		DRM_ERROR("regmap i2c init failed\n");
+		return PTR_ERR(lt9611->regmap);
+	}
+
+	ret = lt9611_parse_dt(&client->dev, lt9611);
+	if (ret) {
+		dev_err(dev, "failed to parse device tree\n");
+		return ret;
+	}
+
+	ret = lt9611_gpio_init(lt9611);
+	if (ret < 0)
+		return ret;
+
+	ret = lt9611_regulator_init(lt9611);
+	if (ret < 0)
+		return ret;
+
+	lt9611_assert_5v(lt9611);
+
+	ret = lt9611_regulator_enable(lt9611);
+	if (ret)
+		return ret;
+
+	lt9611_reset(lt9611);
+
+	ret = lt9611_read_device_rev(lt9611);
+	if (ret) {
+		dev_err(dev, "failed to read chip rev\n");
+		goto err_disable_regulators;
+	}
+
+	ret = devm_request_threaded_irq(dev, client->irq, NULL,
+					lt9611_irq_thread_handler,
+					IRQF_ONESHOT, "lt9611", lt9611);
+	if (ret) {
+		dev_err(dev, "failed to request irq\n");
+		goto err_disable_regulators;
+	}
+
+	i2c_set_clientdata(client, lt9611);
+
+	lt9611->bridge.funcs = &lt9611_bridge_funcs;
+	lt9611->bridge.of_node = client->dev.of_node;
+
+	drm_bridge_add(&lt9611->bridge);
+
+	lt9611_enable_hpd_interrupts(lt9611);
+
+	return 0;
+
+err_disable_regulators:
+	regulator_bulk_disable(ARRAY_SIZE(lt9611->supplies), lt9611->supplies);
+
+	of_node_put(lt9611->dsi0_node);
+	of_node_put(lt9611->dsi1_node);
+
+	return ret;
+}
+
+static int lt9611_remove(struct i2c_client *client)
+{
+	struct lt9611 *lt9611 = i2c_get_clientdata(client);
+
+	disable_irq(client->irq);
+	drm_bridge_remove(&lt9611->bridge);
+
+	regulator_bulk_disable(ARRAY_SIZE(lt9611->supplies), lt9611->supplies);
+
+	of_node_put(lt9611->dsi0_node);
+	of_node_put(lt9611->dsi1_node);
+
+	return 0;
+}
+
+static struct i2c_device_id lt9611_id[] = {
+	{ "lontium,lt9611", 0},
+	{}
+};
+
+static const struct of_device_id lt9611_match_table[] = {
+	{.compatible = "lontium,lt9611"},
+	{}
+};
+MODULE_DEVICE_TABLE(of, lt9611_match_table);
+
+static struct i2c_driver lt9611_driver = {
+	.driver = {
+		.name = "lt9611",
+		.of_match_table = lt9611_match_table,
+	},
+	.probe = lt9611_probe,
+	.remove = lt9611_remove,
+	.id_table = lt9611_id,
+};
+module_i2c_driver(lt9611_driver);
+
+MODULE_LICENSE("GPL v2");
-- 
2.25.4