Re: [PATCH v3 2/2] drm/bridge: This patch add new DRM bridge driver for LT9611C(EX/UXD) chip

Dmitry Baryshkov
2026-04-20T12:18:35Z

On Mon, Apr 20, 2026 at 02:16:44PM +0800, syyang@lontium.com wrote:
> From: Sunyun Yang <syyang@lontium.com>
>
> LT9611C(EX/UXD) is a high performance Single/Dual-Port MIPI to
> HDMI 1.4/2.0 converter:
>
> -Single/Dual-port MIPI DSI Receiver
> 1. Compliantwith D-PHY1.2&DSI-2 1.0
> 2. 1/2configurable ports
> 3. 1 clock lane and 1/2/3/4 configurable data lanes per port
> 4. 80Mbps~2.5Gbps per data lane
> 5. Support RGB666, loosely RGB666, RGB888, RGB565,16-bit YCbCr4:2:2
>
> -HDMI 1.4/2.0 Transmitter
> 1.Data rate up to 6Gbps
> 2.Support HDCP1.4/2.3
> 3.Support CEC,HDR10
> 4.Support lane swap
>
> -audio
> 1.sample rates of 32~192 KHz and sample sizes
> of 16~24 bits
> 2.SPDIF interface supports PCM, Dolbydigital, DTS digital audio
> at up to 192KHz frame rate
>
> -Miscellaneous
> 1.CSC:RGB<->YUV444<->YUV422
>
> Signed-off-by: Sunyun Yang <syyang@lontium.com>
> ---
> drivers/gpu/drm/bridge/Kconfig | 18 +
> drivers/gpu/drm/bridge/Makefile | 1 +
> drivers/gpu/drm/bridge/lontium-lt9611c.c | 1365 ++++++++++++++++++++++
> 3 files changed, 1384 insertions(+)
> create mode 100755 drivers/gpu/drm/bridge/lontium-lt9611c.c
>
> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> index c3209b0f4678..32b85a2a65d9 100644
> --- a/drivers/gpu/drm/bridge/Kconfig
> +++ b/drivers/gpu/drm/bridge/Kconfig
> @@ -177,6 +177,24 @@ config DRM_LONTIUM_LT9611
> HDMI signals
> Please say Y if you have such hardware.
>
> +config DRM_LONTIUM_LT9611C
> + tristate "Lontium LT9611C DSI/HDMI bridge"
> + select SND_SOC_HDMI_CODEC if SND_SOC
> + depends on OF
> + select CRC8
> + select FW_LOADER
> + select DRM_PANEL_BRIDGE
> + select DRM_KMS_HELPER
> + select DRM_MIPI_DSI
> + select DRM_DISPLAY_HELPER
> + select DRM_DISPLAY_HDMI_STATE_HELPER
> + select REGMAP_I2C
> + help
> + Driver for Lontium 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_LONTIUM_LT9611UXC
> tristate "Lontium LT9611UXC DSI/HDMI bridge"
> select SND_SOC_HDMI_CODEC if SND_SOC
> diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
> index beab5b695a6e..92688be9692f 100644
> --- a/drivers/gpu/drm/bridge/Makefile
> +++ b/drivers/gpu/drm/bridge/Makefile
> @@ -16,6 +16,7 @@ obj-$(CONFIG_DRM_ITE_IT6505) += ite-it6505.o
> obj-$(CONFIG_DRM_LONTIUM_LT8912B) += lontium-lt8912b.o
> obj-$(CONFIG_DRM_LONTIUM_LT9211) += lontium-lt9211.o
> obj-$(CONFIG_DRM_LONTIUM_LT9611) += lontium-lt9611.o
> +obj-$(CONFIG_DRM_LONTIUM_LT9611C) += lontium-lt9611c.o
> obj-$(CONFIG_DRM_LONTIUM_LT9611UXC) += lontium-lt9611uxc.o
> obj-$(CONFIG_DRM_LONTIUM_LT8713SX) += lontium-lt8713sx.o
> obj-$(CONFIG_DRM_LVDS_CODEC) += lvds-codec.o
> diff --git a/drivers/gpu/drm/bridge/lontium-lt9611c.c b/drivers/gpu/drm/bridge/lontium-lt9611c.c
> new file mode 100755
> index 000000000000..a6d11d0bddf5
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/lontium-lt9611c.c
> @@ -0,0 +1,1365 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2026 Lontium Semiconductor, Inc.
> + */
> +
> +#include <linux/crc8.h>
> +#include <linux/firmware.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/i2c.h>
> +#include <linux/interrupt.h>
> +#include <linux/media-bus-format.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/of_graph.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
> +
> +#include <drm/drm_atomic_helper.h>
> +#include <drm/drm_bridge.h>
> +#include <drm/drm_connector.h>
> +#include <drm/drm_drv.h>
> +#include <drm/drm_edid.h>
> +#include <drm/drm_mipi_dsi.h>
> +#include <drm/drm_modes.h>
> +#include <drm/drm_of.h>
> +#include <drm/drm_print.h>
> +#include <drm/drm_probe_helper.h>
> +
> +#include <drm/display/drm_hdmi_audio_helper.h>
> +#include <drm/display/drm_hdmi_state_helper.h>
> +#include <sound/hdmi-codec.h>
> +
> +#define FW_SIZE (64 * 1024)
> +#define LT_PAGE_SIZE 256
> +#define FW_FILE "LT9611C.bin"

lt9611c_fw.bin

> +#define LT9611C_CRC_POLYNOMIAL 0x31
> +#define LT9611C_PAGE_CONTROL 0xff
> +
> +struct lt9611c {
> + struct device *dev;
> + struct i2c_client *client;
> + struct drm_bridge bridge;
> + struct drm_bridge *next_bridge;

Use drm_bridge::next_bridge instead.

> + struct regmap *regmap;
> + /* Protects all accesses to registers by stopping the on-chip MCU */
> + struct mutex ocm_lock;
> + struct work_struct work;
> + struct device_node *dsi0_node;
> + struct device_node *dsi1_node;
> + struct mipi_dsi_device *dsi0;
> + struct mipi_dsi_device *dsi1;
> + struct gpio_desc *reset_gpio;
> + struct regulator_bulk_data supplies[2];
> + u32 chip_type;

Define a enum. Having if (chip_type == 2) doesn't help readability.

> + const struct firmware *fw;

Please drop it from the global struct. It is not necessary once the
bridge is up and running.

> + int fw_version;
> + u8 fw_crc;
> + bool hdmi_connected;

You've lost the imortant comment here.

> +};
> +
> +DECLARE_CRC8_TABLE(lt9611c_crc8_table);
> +
> +static const struct regmap_range_cfg lt9611c_ranges[] = {
> + {
> + .name = "register_range",
> + .range_min = 0,
> + .range_max = 0xffff,
> + .selector_reg = LT9611C_PAGE_CONTROL,
> + .selector_mask = 0xff,
> + .selector_shift = 0,
> + .window_start = 0,
> + .window_len = 0x100,
> + },
> +};
> +
> +static const struct regmap_config lt9611c_regmap_config = {
> + .reg_bits = 8,
> + .val_bits = 8,
> + .max_register = 0xffff,
> + .ranges = lt9611c_ranges,
> + .num_ranges = ARRAY_SIZE(lt9611c_ranges),
> +};
> +
> +static int lt9611c_read_write_flow(struct lt9611c *lt9611c, u8 *params,
> + unsigned int param_count, u8 *return_buffer,
> + unsigned int return_count)
> +{
> + int count, i;
> + unsigned int temp;
> +
> + regmap_write(lt9611c->regmap, 0xe0de, 0x01);
> +
> + count = 0;
> + do {
> + regmap_read(lt9611c->regmap, 0xe0ae, &temp);
> + usleep_range(1000, 2000);
> + count++;
> + } while (count < 100 && temp != 0x01);

read_poll_timeout()

> +
> + if (temp != 0x01)
> + return -1;

-ETIMEDOUT

> +
> + for (i = 0; i < param_count; i++) {
> + if (i > 0xdd - 0xb0)

0xe0dd - 0xe0b0 at least.

> + break;
> +
> + regmap_write(lt9611c->regmap, 0xe0b0 + i, params[i]);
> + }
> +
> + regmap_write(lt9611c->regmap, 0xe0de, 0x02);
> +
> + count = 0;
> + do {
> + regmap_read(lt9611c->regmap, 0xe0ae, &temp);
> + usleep_range(1000, 2000);
> + count++;
> + } while (count < 100 && temp != 0x02);

Again, read_poll_timeout().

> +
> + if (temp != 0x02)
> + return -2;

-ETIMEDOUT

> +
> + regmap_bulk_read(lt9611c->regmap, 0xe085, return_buffer, return_count);
> +
> + return 0;
> +}
> +
> +static int lt9611c_prepare_firmware_data(struct lt9611c *lt9611c)
> +{
> + struct device *dev = lt9611c->dev;
> + int ret;
> + u8 *buffer;
> + size_t total_size = FW_SIZE - 1;
> +
> + ret = request_firmware(&lt9611c->fw, FW_FILE, dev);
> + if (ret) {
> + dev_err(dev, "failed load file '%s', error type %d\n", FW_FILE, ret);
> + return -EPROBE_DEFER;
> + }
> +
> + if (lt9611c->fw->size > total_size) {
> + dev_err(dev, "firmware too large (%zu > %zu)\n", lt9611c->fw->size, total_size);
> + release_firmware(lt9611c->fw);
> + lt9611c->fw = NULL;
> + return -EINVAL;
> + }
> +
> + dev_dbg(dev, "firmware size: %zu bytes\n", lt9611c->fw->size);
> +
> + buffer = kzalloc(total_size, GFP_KERNEL);
> + if (!buffer) {
> + release_firmware(lt9611c->fw);
> + lt9611c->fw = NULL;
> + return -ENOMEM;
> + }
> +
> + memset(buffer, 0xff, total_size);
> + memcpy(buffer, lt9611c->fw->data, lt9611c->fw->size);
> +
> + lt9611c->fw_crc = crc8(lt9611c_crc8_table, buffer, total_size, 0);
> +
> + dev_dbg(dev, "firmware crc: 0x%02x\n", lt9611c->fw_crc);
> +
> + kfree(buffer);
> + return 0;
> +}
> +
> +static void lt9611c_config_parameters(struct lt9611c *lt9611c)
> +{
> + const struct reg_sequence seq_write_paras[] = {
> + REG_SEQ0(0xe0ee, 0x01),
> + REG_SEQ0(0xe103, 0x3f), //fifo rst
> + REG_SEQ0(0xe103, 0xff),
> + REG_SEQ0(0xe05e, 0xc1),
> + REG_SEQ0(0xe058, 0x00),
> + REG_SEQ0(0xe059, 0x50),
> + REG_SEQ0(0xe05a, 0x10),
> + REG_SEQ0(0xe05a, 0x00),
> + REG_SEQ0(0xe058, 0x21),
> + };
> +
> + regmap_multi_reg_write(lt9611c->regmap, seq_write_paras, ARRAY_SIZE(seq_write_paras));
> +}
> +
> +static void lt9611c_wren(struct lt9611c *lt9611c)
> +{
> + regmap_write(lt9611c->regmap, 0xe05a, 0x04);
> + regmap_write(lt9611c->regmap, 0xe05a, 0x00);
> +}
> +
> +static void lt9611c_wrdi(struct lt9611c *lt9611c)
> +{
> + regmap_write(lt9611c->regmap, 0xe05a, 0x08);
> + regmap_write(lt9611c->regmap, 0xe05a, 0x00);
> +}
> +
> +static void lt9611c_erase_op(struct lt9611c *lt9611c, u32 addr)
> +{
> + const struct reg_sequence seq_write[] = {
> + REG_SEQ0(0xe0ee, 0x01),
> + REG_SEQ0(0xe05a, 0x04),
> + REG_SEQ0(0xe05a, 0x00),
> + REG_SEQ0(0xe05b, (addr >> 16) & 0xff),
> + REG_SEQ0(0xe05c, (addr >> 8) & 0xff),
> + REG_SEQ0(0xe05d, addr & 0xff),
> + REG_SEQ0(0xe05a, 0x01),
> + REG_SEQ0(0xe05a, 0x00),
> + };
> +
> + regmap_multi_reg_write(lt9611c->regmap, seq_write, ARRAY_SIZE(seq_write));
> +}
> +
> +static void read_flash_reg_status(struct lt9611c *lt9611c, unsigned int *status)
> +{
> + const struct reg_sequence seq_write[] = {
> + REG_SEQ0(0xe103, 0x3f),
> + REG_SEQ0(0xe103, 0xff),
> + REG_SEQ0(0xe05e, 0x40),
> + REG_SEQ0(0xe056, 0x05),
> + REG_SEQ0(0xe055, 0x25),
> + REG_SEQ0(0xe055, 0x01),
> + REG_SEQ0(0xe058, 0x21),
> + };
> +
> + regmap_multi_reg_write(lt9611c->regmap, seq_write, ARRAY_SIZE(seq_write));
> +
> + regmap_read(lt9611c->regmap, 0xe05f, status);
> +}
> +
> +static void lt9611c_crc_to_sram(struct lt9611c *lt9611c)
> +{
> + const struct reg_sequence seq_write[] = {
> + REG_SEQ0(0xe051, 0x00),
> + REG_SEQ0(0xe055, 0xc0),
> + REG_SEQ0(0xe055, 0x80),
> + REG_SEQ0(0xe05e, 0xc0),
> + REG_SEQ0(0xe058, 0x21),
> + };
> +
> + regmap_multi_reg_write(lt9611c->regmap, seq_write, ARRAY_SIZE(seq_write));
> +}
> +
> +static void lt9611c_data_to_sram(struct lt9611c *lt9611c)
> +{
> + const struct reg_sequence seq_write[] = {
> + REG_SEQ0(0xe051, 0xff),
> + REG_SEQ0(0xe055, 0x80),
> + REG_SEQ0(0xe05e, 0xc0),
> + REG_SEQ0(0xe058, 0x21),
> + };
> +
> + regmap_multi_reg_write(lt9611c->regmap, seq_write, ARRAY_SIZE(seq_write));
> +}
> +
> +static void lt9611c_sram_to_flash(struct lt9611c *lt9611c, size_t addr)
> +{
> + const struct reg_sequence seq_write[] = {
> + REG_SEQ0(0xe05b, (addr >> 16) & 0xff),
> + REG_SEQ0(0xe05c, (addr >> 8) & 0xff),
> + REG_SEQ0(0xe05d, addr & 0xff),
> + REG_SEQ0(0xe05a, 0x30),
> + REG_SEQ0(0xe05a, 0x00),
> + };
> +
> + regmap_multi_reg_write(lt9611c->regmap, seq_write, ARRAY_SIZE(seq_write));
> +}
> +
> +static void lt9611c_block_erase(struct lt9611c *lt9611c)
> +{
> + struct device *dev = lt9611c->dev;
> + int i;
> + unsigned int block_num;
> + unsigned int flash_status = 0;
> + u32 flash_addr = 0;
> +
> + for (block_num = 0; block_num < 2; block_num++) {
> + flash_addr = (block_num * 0x008000);
> + lt9611c_erase_op(lt9611c, flash_addr);
> + msleep(100);
> + i = 0;
> + while (1) {
> + read_flash_reg_status(lt9611c, &flash_status);
> + if ((flash_status & 0x01) == 0)
> + break;
> +
> + if (i > 50)
> + break;
> +
> + i++;
> + msleep(50);
> + }
> + }
> +
> + dev_dbg(dev, "erase flash done.\n");
> +}
> +
> +static int lt9611c_write_data(struct lt9611c *lt9611c, size_t addr)
> +{
> + struct device *dev = lt9611c->dev;
> + int ret;
> + unsigned int page = 0, num = 0, i = 0;
> + size_t size, index;
> + const u8 *data;
> + u8 value;
> +
> + data = lt9611c->fw->data;
> + size = lt9611c->fw->size;
> + page = (size + LT_PAGE_SIZE - 1) / LT_PAGE_SIZE;
> + if (page * LT_PAGE_SIZE > FW_SIZE) {
> + dev_err(dev, "firmware size out of range\n");
> + return -EINVAL;
> + }
> +
> + dev_dbg(dev, "%u pages, total size %zu byte\n", page, size);
> +
> + for (num = 0; num < page; num++) {
> + lt9611c_data_to_sram(lt9611c);
> +
> + for (i = 0; i < LT_PAGE_SIZE; i++) {
> + index = num * LT_PAGE_SIZE + i;
> + value = (index < size) ? data[index] : 0xff;
> +
> + ret = regmap_write(lt9611c->regmap, 0xe059, value);
> + if (ret < 0) {
> + dev_err(dev, "write error at page %u, index %u\n", num, i);
> + return ret;
> + }
> + }
> +
> + lt9611c_wren(lt9611c);
> + lt9611c_sram_to_flash(lt9611c, addr);
> +
> + addr += LT_PAGE_SIZE;
> + }
> +
> + lt9611c_wrdi(lt9611c);
> +
> + return 0;
> +}
> +
> +static int lt9611c_write_crc(struct lt9611c *lt9611c, size_t addr)
> +{
> + struct device *dev = lt9611c->dev;
> + int ret;
> + u8 crc;
> +
> + crc = lt9611c->fw_crc;
> + lt9611c_crc_to_sram(lt9611c);
> + ret = regmap_write(lt9611c->regmap, 0xe059, crc);
> + if (ret < 0) {
> + dev_err(dev, "failed to write crc\n");
> + return ret;
> + }
> +
> + lt9611c_wren(lt9611c);
> + lt9611c_sram_to_flash(lt9611c, addr);
> + lt9611c_wrdi(lt9611c);
> +
> + dev_dbg(dev, "crc 0x%02x written to flash at addr 0x%zx\n", crc, addr);
> +
> + return 0;
> +}
> +
> +static int lt9611c_firmware_upgrade(struct lt9611c *lt9611c)
> +{
> + struct device *dev = lt9611c->dev;
> + int ret;
> +
> + ret = lt9611c_prepare_firmware_data(lt9611c);
> + if (ret < 0)
> + return ret;
> +
> + dev_dbg(dev, "starting firmware upgrade, size: %zu bytes\n", lt9611c->fw->size);
> +
> + lt9611c_config_parameters(lt9611c);
> + lt9611c_block_erase(lt9611c);
> +
> + ret = lt9611c_write_data(lt9611c, 0);
> + if (ret < 0) {
> + dev_err(dev, "failed to write firmware data\n");
> + return ret;
> + }
> +
> + release_firmware(lt9611c->fw);
> + lt9611c->fw = NULL;
> +
> + ret = lt9611c_write_crc(lt9611c, FW_SIZE - 1);
> + if (ret < 0) {
> + dev_err(dev, "failed to write firmware crc\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int lt9611c_upgrade_result(struct lt9611c *lt9611c)
> +{
> + struct device *dev = lt9611c->dev;
> + unsigned int crc_result;
> +
> + regmap_write(lt9611c->regmap, 0xe0ee, 0x01);
> + regmap_read(lt9611c->regmap, 0xe021, &crc_result);
> +
> + if (crc_result != lt9611c->fw_crc) {
> + dev_err(dev, "lt9611c fw upgrade failed, expected crc=0x%02x, read crc=0x%02x\n",
> + lt9611c->fw_crc, crc_result);
> + return -1;
> + }
> +
> + dev_dbg(dev, "lt9611c firmware upgrade success, crc=0x%02x\n", crc_result);
> + return 0;
> +}
> +
> +static struct lt9611c *bridge_to_lt9611c(struct drm_bridge *bridge)
> +{
> + return container_of(bridge, struct lt9611c, bridge);
> +}
> +
> +/*read only*/
> +static const struct lt9611c *bridge_to_lt9611c_const(const struct drm_bridge *bridge)
> +{
> + return container_of(bridge, const struct lt9611c, bridge);
> +}
> +
> +static void lt9611c_lock(struct lt9611c *lt9611c)
> +{
> + mutex_lock(&lt9611c->ocm_lock);
> + regmap_write(lt9611c->regmap, 0xe0ee, 0x01);
> +}
> +
> +static void lt9611c_unlock(struct lt9611c *lt9611c)
> +{
> + regmap_write(lt9611c->regmap, 0xe0ee, 0x00);
> + mutex_unlock(&lt9611c->ocm_lock);
> +}
> +
> +static irqreturn_t lt9611c_irq_thread_handler(int irq, void *dev_id)
> +{
> + struct lt9611c *lt9611c = dev_id;
> + struct device *dev = lt9611c->dev;
> + int ret;
> + unsigned int irq_status;
> + u8 cmd[5] = {0x52, 0x48, 0x31, 0x3a, 0x00};
> + u8 data[5];
> +
> + mutex_lock(&lt9611c->ocm_lock);

Where applicable (like here) please switch to
guard(mutex)(&lt9611c->ocm_lock);

> +
> + regmap_read(lt9611c->regmap, 0xe084, &irq_status);
> + if (!(irq_status & BIT(0))) {
> + mutex_unlock(&lt9611c->ocm_lock);
> + return IRQ_HANDLED;
> + }
> +
> + ret = lt9611c_read_write_flow(lt9611c, cmd, 5, data, 5);

Here and in all other places. Switch to ARRAY_SIZE instead of specifying
lengths directly.

> + if (ret) {
> + dev_err(dev, "failed to read HPD status\n");
> + } else {
> + lt9611c->hdmi_connected = (data[4] == 0x02);
> + dev_dbg(dev, "HDMI %s\n", lt9611c->hdmi_connected ? "connected" : "disconnected");
> + }
> +
> + schedule_work(&lt9611c->work);
> +
> + /*clear interrupt*/
> + regmap_write(lt9611c->regmap, 0xe0df, irq_status & BIT(0));
> + //hardware need delay
> + usleep_range(10000, 12000);
> + regmap_write(lt9611c->regmap, 0xe0df, irq_status & (~BIT(0)));
> +
> + mutex_unlock(&lt9611c->ocm_lock);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static void lt9611c_hpd_work(struct work_struct *work)
> +{
> + struct lt9611c *lt9611c = container_of(work, struct lt9611c, work);
> + bool connected;
> +
> + mutex_lock(&lt9611c->ocm_lock);
> + connected = lt9611c->hdmi_connected;
> + mutex_unlock(&lt9611c->ocm_lock);
> +
> + drm_bridge_hpd_notify(&lt9611c->bridge,
> + connected ? connector_status_connected :
> + connector_status_disconnected);
> +}
> +
> +static void lt9611c_reset(struct lt9611c *lt9611c)
> +{
> + gpiod_set_value_cansleep(lt9611c->reset_gpio, 1);
> + msleep(20);
> +
> + gpiod_set_value_cansleep(lt9611c->reset_gpio, 0);
> + msleep(20);
> +
> + gpiod_set_value_cansleep(lt9611c->reset_gpio, 1);
> + msleep(400);
> +
> + dev_dbg(lt9611c->dev, "lt9611c reset");
> +}
> +
> +static int lt9611c_regulator_init(struct lt9611c *lt9611c)
> +{
> + struct device *dev = lt9611c->dev;
> + int ret;
> +
> + lt9611c->supplies[0].supply = "vcc";
> + lt9611c->supplies[1].supply = "vdd";
> +
> + ret = devm_regulator_bulk_get(dev, 2, lt9611c->supplies);
> +
> + return ret;
> +}
> +
> +static int lt9611c_regulator_enable(struct lt9611c *lt9611c)
> +{
> + int ret;
> +
> + ret = regulator_enable(lt9611c->supplies[0].consumer);
> + if (ret < 0)
> + return ret;
> +
> + usleep_range(5000, 10000);
> +
> + ret = regulator_enable(lt9611c->supplies[1].consumer);
> + if (ret < 0) {
> + regulator_disable(lt9611c->supplies[0].consumer);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int lt9611c_regulator_disable(struct lt9611c *lt9611c)
> +{
> + int ret;
> +
> + ret = regulator_disable(lt9611c->supplies[0].consumer);
> + if (ret < 0)
> + return ret;
> +
> + ret = regulator_disable(lt9611c->supplies[1].consumer);
> + if (ret < 0)
> + return ret;
> +
> + return 0;
> +}
> +
> +static struct mipi_dsi_device *lt9611c_attach_dsi(struct lt9611c *lt9611c,
> + struct device_node *dsi_node)
> +{
> + const struct mipi_dsi_device_info info = { "lt9611c", 0, NULL };
> + struct mipi_dsi_device *dsi;
> + struct mipi_dsi_host *host;
> + struct device *dev = lt9611c->dev;
> + int ret;
> +
> + host = of_find_mipi_dsi_host_by_node(dsi_node);
> + if (!host) {
> + dev_err(dev, "failed to find dsi host\n");
> + return ERR_PTR(-EPROBE_DEFER);

here and futher, in the probe path use `return dev_err_probe()`.

> + }
> +
> + dsi = devm_mipi_dsi_device_register_full(dev, host, &info);
> + if (IS_ERR(dsi)) {
> + dev_err(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 = devm_mipi_dsi_attach(dev, dsi);
> + if (ret < 0) {
> + dev_err(dev, "failed to attach dsi to host\n");
> + return ERR_PTR(ret);
> + }
> +
> + return dsi;
> +}
> +
> +static int lt9611c_bridge_attach(struct drm_bridge *bridge,
> + struct drm_encoder *encoder,
> + enum drm_bridge_attach_flags flags)
> +{
> + struct lt9611c *lt9611c = bridge_to_lt9611c(bridge);
> +
> + return drm_bridge_attach(encoder, lt9611c->next_bridge, bridge, flags);
> +}
> +
> +static enum drm_mode_status
> +lt9611c_hdmi_tmds_char_rate_valid(const struct drm_bridge *bridge,
> + const struct drm_display_mode *mode,
> + unsigned long long tmds_rate)
> +{
> + const struct lt9611c *lt9611c = bridge_to_lt9611c_const(bridge);
> +
> + if (lt9611c->chip_type == 2) {
> + /*lt9611uxd use*/
> + if (tmds_rate > 600000000)
> + return MODE_CLOCK_HIGH;
> +
> + } else {
> + if (tmds_rate > 340000000)
> + return MODE_CLOCK_HIGH;
> + }
> +
> + if (tmds_rate < 25000000)
> + return MODE_CLOCK_LOW;
> +
> + return MODE_OK;
> +}
> +
> +static void lt9611c_video_setup(struct lt9611c *lt9611c,
> + const struct drm_display_mode *mode)
> +{
> + struct device *dev = lt9611c->dev;
> + int ret;
> + u32 h_total, hactive, hsync_len, hfront_porch, hback_porch;
> + u32 v_total, vactive, vsync_len, vfront_porch, vback_porch;
> + u8 video_timing_set_cmd[26] = {0x57, 0x4d, 0x33, 0x3a};
> + u8 return_timing_set_param[3];
> + u8 framerate;
> + u8 vic = 0x00;
> +
> + mutex_lock(&lt9611c->ocm_lock);
> +
> + h_total = mode->htotal;
> + hactive = mode->hdisplay;
> + hsync_len = mode->hsync_end - mode->hsync_start;
> + hfront_porch = mode->hsync_start - mode->hdisplay;
> + hback_porch = mode->htotal - mode->hsync_end;
> +
> + v_total = mode->vtotal;
> + vactive = mode->vdisplay;
> + vsync_len = mode->vsync_end - mode->vsync_start;
> + vfront_porch = mode->vsync_start - mode->vdisplay;
> + vback_porch = mode->vtotal - mode->vsync_end;
> + framerate = drm_mode_vrefresh(mode);
> + vic = drm_match_cea_mode(mode);
> +
> + dev_dbg(dev, "hactive=%d, vactive=%d\n", hactive, vactive);
> + dev_dbg(dev, "framerate=%d\n", framerate);
> + dev_dbg(dev, "vic = 0x%02x\n", vic);
> +
> + video_timing_set_cmd[4] = (h_total >> 8) & 0xff;
> + video_timing_set_cmd[5] = h_total & 0xff;
> + video_timing_set_cmd[6] = (hactive >> 8) & 0xff;
> + video_timing_set_cmd[7] = hactive & 0xff;
> + video_timing_set_cmd[8] = (hfront_porch >> 8) & 0xff;
> + video_timing_set_cmd[9] = hfront_porch & 0xff;
> + video_timing_set_cmd[10] = (hsync_len >> 8) & 0xff;
> + video_timing_set_cmd[11] = hsync_len & 0xff;
> + video_timing_set_cmd[12] = (hback_porch >> 8) & 0xff;
> + video_timing_set_cmd[13] = hback_porch & 0xff;
> + video_timing_set_cmd[14] = (v_total >> 8) & 0xff;
> + video_timing_set_cmd[15] = v_total & 0xff;
> + video_timing_set_cmd[16] = (vactive >> 8) & 0xff;
> + video_timing_set_cmd[17] = vactive & 0xFF;
> + video_timing_set_cmd[18] = (vfront_porch >> 8) & 0xff;
> + video_timing_set_cmd[19] = vfront_porch & 0xff;
> + video_timing_set_cmd[20] = (vsync_len >> 8) & 0xff;
> + video_timing_set_cmd[21] = vsync_len & 0xff;
> + video_timing_set_cmd[22] = (vback_porch >> 8) & 0xff;
> + video_timing_set_cmd[23] = vback_porch & 0xff;
> + video_timing_set_cmd[24] = framerate;
> + video_timing_set_cmd[25] = vic;
> +
> + ret = lt9611c_read_write_flow(lt9611c,
> + video_timing_set_cmd, 26,
> + return_timing_set_param, 3);
> + if (ret)
> + dev_err(dev, "video set failed\n");
> + mutex_unlock(&lt9611c->ocm_lock);
> +}
> +
> +static void lt9611c_bridge_atomic_enable(struct drm_bridge *bridge,
> + struct drm_atomic_state *state)
> +{
> + struct lt9611c *lt9611c = bridge_to_lt9611c(bridge);
> + struct drm_connector *connector;
> + struct drm_connector_state *conn_state;
> + struct drm_crtc_state *crtc_state;
> + struct drm_display_mode *mode;
> +
> + connector = drm_atomic_get_new_connector_for_encoder(state, bridge->encoder);
> + if (WARN_ON(!connector))
> + return;
> +
> + conn_state = drm_atomic_get_new_connector_state(state, connector);
> + if (WARN_ON(!conn_state))
> + return;
> +
> + crtc_state = drm_atomic_get_new_crtc_state(state, conn_state->crtc);
> + if (WARN_ON(!crtc_state))
> + return;
> +
> + mode = &crtc_state->adjusted_mode;
> +
> + lt9611c_video_setup(lt9611c, mode);
> +}
> +
> +static enum drm_connector_status
> +lt9611c_bridge_detect(struct drm_bridge *bridge, struct drm_connector *connector)
> +{
> + struct lt9611c *lt9611c = bridge_to_lt9611c(bridge);
> + struct device *dev = lt9611c->dev;
> + int ret;
> + bool connected = false;
> + u8 cmd[5] = {0x52, 0x48, 0x31, 0x3a, 0x00};
> + u8 data[5];
> +
> + mutex_lock(&lt9611c->ocm_lock);
> +
> + ret = lt9611c_read_write_flow(lt9611c, cmd, 5, data, 5);
> + if (ret)
> + dev_err(dev, "failed to read HPD status (err=%d)\n", ret);
> + else
> + connected = (data[4] == 0x02);
> +
> + lt9611c->hdmi_connected = connected;
> +
> + mutex_unlock(&lt9611c->ocm_lock);
> +
> + return connected ? connector_status_connected :
> + connector_status_disconnected;
> +}
> +
> +static int lt9611c_get_edid_block(void *data, u8 *buf,
> + unsigned int block, size_t len)
> +{
> + struct lt9611c *lt9611c = data;
> + struct device *dev = lt9611c->dev;
> + u8 cmd[5] = {0x52, 0x48, 0x33, 0x3a, 0x00};
> + u8 packet[37];
> + int ret, i, offset = 0;
> +
> + if (len != 128)
> + return -EINVAL;
> + mutex_lock(&lt9611c->ocm_lock);
> +
> + for (i = 0; i < 4; i++) {
> + cmd[4] = block * 4 + i;
> + ret = lt9611c_read_write_flow(lt9611c, cmd, sizeof(cmd),
> + packet, sizeof(packet));
> + if (ret) {
> + dev_err(dev, "Failed to read EDID block %u packet %d\n",
> + block, i);
> + mutex_unlock(&lt9611c->ocm_lock);
> + return ret;
> + }
> +
> + memcpy(buf + offset, &packet[5], 32);
> + offset += 32;
> + }
> +
> + mutex_unlock(&lt9611c->ocm_lock);
> +
> + return 0;
> +}
> +
> +static const struct drm_edid *lt9611c_bridge_edid_read(struct drm_bridge *bridge,
> + struct drm_connector *connector)
> +{
> + struct lt9611c *lt9611c = bridge_to_lt9611c(bridge);
> +
> + return drm_edid_read_custom(connector, lt9611c_get_edid_block, lt9611c);
> +}
> +
> +static void lt9611c_bridge_hpd_notify(struct drm_bridge *bridge,
> + struct drm_connector *connector,
> + enum drm_connector_status status)
> +{
> + const struct drm_edid *drm_edid;
> +
> + if (status == connector_status_disconnected) {
> + drm_connector_hdmi_audio_plugged_notify(connector, false);
> + drm_edid_connector_update(connector, NULL);
> + return;
> + }
> +
> + drm_edid = lt9611c_bridge_edid_read(bridge, connector);
> + drm_edid_connector_update(connector, drm_edid);
> + drm_edid_free(drm_edid);
> +
> + if (status == connector_status_connected)
> + drm_connector_hdmi_audio_plugged_notify(connector, true);
> +}
> +
> +static int lt9611c_hdmi_write_audio_infoframe(struct drm_bridge *bridge,
> + const u8 *buffer, size_t len)
> +{
> + struct lt9611c *lt9611c = bridge_to_lt9611c(bridge);
> + u8 audio_infoframe_cmd[16] = {0x57, 0x48, 0x35, 0x3a, 0x02};
> + u8 data[5];
> + int i, ret;
> +
> + for (i = 0; i < len; i++)
> + audio_infoframe_cmd[i + 5] = buffer[i];
> +
> + mutex_lock(&lt9611c->ocm_lock);
> +
> + ret = lt9611c_read_write_flow(lt9611c, audio_infoframe_cmd, sizeof(audio_infoframe_cmd),
> + data, sizeof(data));
> + mutex_unlock(&lt9611c->ocm_lock);
> +
> + if (ret < 0) {
> + dev_err(lt9611c->dev, "write audio infoframe failed!\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int lt9611c_hdmi_clear_audio_infoframe(struct drm_bridge *bridge)
> +{
> + return 0;

Hmm? What if we need to clear the infoframe?

> +}
> +
> +static int lt9611c_hdmi_write_avi_infoframe(struct drm_bridge *bridge,
> + const u8 *buffer, size_t len)
> +{
> + struct lt9611c *lt9611c = bridge_to_lt9611c(bridge);
> + u8 avi_infoframe_cmd[16] = {0x57, 0x48, 0x35, 0x3a, 0x01};
> + u8 data[5];
> + int i, ret;
> +
> + for (i = 0; i < len; i++)
> + avi_infoframe_cmd[i + 5] = buffer[i];
> +
> + mutex_lock(&lt9611c->ocm_lock);
> +
> + ret = lt9611c_read_write_flow(lt9611c, avi_infoframe_cmd, sizeof(avi_infoframe_cmd),
> + data, sizeof(data));
> + mutex_unlock(&lt9611c->ocm_lock);
> +
> + if (ret < 0) {
> + dev_err(lt9611c->dev, "write avi infoframe failed!\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int lt9611c_hdmi_clear_avi_infoframe(struct drm_bridge *bridge)
> +{

The same question.

> + return 0;
> +}
> +
> +static int lt9611c_hdmi_write_spd_infoframe(struct drm_bridge *bridge,
> + const u8 *buffer, size_t len)
> +{
> + struct lt9611c *lt9611c = bridge_to_lt9611c(bridge);
> + u8 spd_infoframe_cmd[16] = {0x57, 0x48, 0x35, 0x3a, 0x04};
> + u8 data[5];
> + int i, ret;
> +
> + for (i = 0; i < len; i++)
> + spd_infoframe_cmd[i + 5] = buffer[i];
> +
> + mutex_lock(&lt9611c->ocm_lock);
> +
> + ret = lt9611c_read_write_flow(lt9611c, spd_infoframe_cmd, sizeof(spd_infoframe_cmd),
> + data, sizeof(data));
> + mutex_unlock(&lt9611c->ocm_lock);
> +
> + if (ret < 0) {
> + dev_err(lt9611c->dev, "write spd infoframe failed!\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int lt9611c_hdmi_clear_spd_infoframe(struct drm_bridge *bridge)
> +{
> + return 0;
> +}
> +
> +static int lt9611c_hdmi_write_hdmi_infoframe(struct drm_bridge *bridge,
> + const u8 *buffer, size_t len)
> +{
> + struct lt9611c *lt9611c = bridge_to_lt9611c(bridge);
> + u8 spd_infoframe_cmd[16] = {0x57, 0x48, 0x35, 0x3a, 0x05};
> + u8 data[5];
> + int i, ret;
> +
> + for (i = 0; i < len; i++)
> + spd_infoframe_cmd[i + 5] = buffer[i];
> +
> + mutex_lock(&lt9611c->ocm_lock);
> +
> + ret = lt9611c_read_write_flow(lt9611c, spd_infoframe_cmd, sizeof(spd_infoframe_cmd),
> + data, sizeof(data));
> + mutex_unlock(&lt9611c->ocm_lock);
> + if (ret < 0) {
> + dev_err(lt9611c->dev, "write hdmi infoframe failed!\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int lt9611c_hdmi_clear_hdmi_infoframe(struct drm_bridge *bridge)
> +{
> + return 0;
> +}
> +
> +static int lt9611c_hdmi_audio_prepare(struct drm_bridge *bridge,
> + struct drm_connector *connector,
> + struct hdmi_codec_daifmt *fmt,
> + struct hdmi_codec_params *hparms)
> +{
> + struct lt9611c *lt9611c = bridge_to_lt9611c(bridge);
> + u8 audio_cmd[6] = {0x57, 0x48, 0x36, 0x3a};
> + u8 data[5];
> + int ret;
> +
> + /* Validate sample rate and width (LT9611C auto-detects but we still check) */

What for? You don't trust ASoC / ALSA core that the rates would match
HDMI_RATES?

> + switch (hparms->sample_rate) {
> + case 32000:
> + case 44100:
> + case 48000:
> + case 88200:
> + case 96000:
> + case 176400:
> + case 192000:
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + switch (hparms->sample_width) {
> + case 16:
> + case 18:
> + case 20:
> + case 24:

and no support for 32?

> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + switch (fmt->fmt) {
> + case HDMI_I2S:
> + audio_cmd[4] = 0x01;
> + break;
> + case HDMI_SPDIF:
> + audio_cmd[4] = 0x02;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + audio_cmd[5] = hparms->channels;
> +
> + mutex_lock(&lt9611c->ocm_lock);
> + ret = lt9611c_read_write_flow(lt9611c, audio_cmd, sizeof(audio_cmd),
> + data, sizeof(data));
> + mutex_unlock(&lt9611c->ocm_lock);
> +
> + if (ret < 0) {
> + dev_err(lt9611c->dev, "set audio info failed!\n");
> + return ret;
> + }
> +
> + return drm_atomic_helper_connector_hdmi_update_audio_infoframe(connector,
> + &hparms->cea);

Please check the indentation.

> +}
> +
> +static void lt9611c_hdmi_audio_shutdown(struct drm_bridge *bridge,
> + struct drm_connector *connector)
> +{
> + drm_atomic_helper_connector_hdmi_clear_audio_infoframe(connector);
> +}
> +
> +static int lt9611c_hdmi_audio_startup(struct drm_bridge *bridge,
> + struct drm_connector *connector)
> +{
> + return 0;
> +}
> +
> +static const struct drm_bridge_funcs lt9611c_bridge_funcs = {
> + .attach = lt9611c_bridge_attach,
> + .detect = lt9611c_bridge_detect,
> + .edid_read = lt9611c_bridge_edid_read,
> + .hpd_notify = lt9611c_bridge_hpd_notify,
> + .atomic_enable = lt9611c_bridge_atomic_enable,
> +
> + .hdmi_tmds_char_rate_valid = lt9611c_hdmi_tmds_char_rate_valid,
> + .hdmi_write_audio_infoframe = lt9611c_hdmi_write_audio_infoframe,
> + .hdmi_clear_audio_infoframe = lt9611c_hdmi_clear_audio_infoframe,
> + .hdmi_write_avi_infoframe = lt9611c_hdmi_write_avi_infoframe,
> + .hdmi_clear_avi_infoframe = lt9611c_hdmi_clear_avi_infoframe,
> + .hdmi_write_spd_infoframe = lt9611c_hdmi_write_spd_infoframe,
> + .hdmi_clear_spd_infoframe = lt9611c_hdmi_clear_spd_infoframe,
> + .hdmi_write_hdmi_infoframe = lt9611c_hdmi_write_hdmi_infoframe,
> + .hdmi_clear_hdmi_infoframe = lt9611c_hdmi_clear_hdmi_infoframe,

You implemented all these callbacks, but you haven't tested them. They
won't be called as is. You would need to set one more DRM bridge OP. And
once set, you can drop the .hpd_notify, it will be handled by the
generic code.

> + .hdmi_audio_startup = lt9611c_hdmi_audio_startup,
> + .hdmi_audio_prepare = lt9611c_hdmi_audio_prepare,
> + .hdmi_audio_shutdown = lt9611c_hdmi_audio_shutdown,
> +};
> +
> +static int lt9611c_parse_dt(struct device *dev,
> + struct lt9611c *lt9611c)
> +{
> + lt9611c->dsi0_node = of_graph_get_remote_node(dev->of_node, 0, -1);
> + if (!lt9611c->dsi0_node) {
> + dev_err(dev, "failed to get remote node for primary dsi\n");
> + return -ENODEV;
> + }
> +
> + lt9611c->dsi1_node = of_graph_get_remote_node(dev->of_node, 1, -1);
> +
> + return drm_of_find_panel_or_bridge(dev->of_node, 2, -1, NULL, &lt9611c->next_bridge);
> +}
> +
> +static int lt9611c_gpio_init(struct lt9611c *lt9611c)
> +{
> + struct device *dev = lt9611c->dev;
> +
> + lt9611c->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
> + if (IS_ERR(lt9611c->reset_gpio)) {
> + dev_err(dev, "failed to acquire reset gpio\n");
> + return PTR_ERR(lt9611c->reset_gpio);
> + }
> +
> + return 0;
> +}
> +
> +static int lt9611c_read_version(struct lt9611c *lt9611c)
> +{
> + u8 buf[2];
> + int ret;
> +
> + ret = regmap_write(lt9611c->regmap, 0xe0ee, 0x01);
> + if (ret)
> + return ret;
> +
> + ret = regmap_bulk_read(lt9611c->regmap, 0xe080, buf, 2);
> + if (ret)
> + return ret;
> +
> + return (buf[0] << 8) | buf[1];
> +}
> +
> +static int lt9611c_read_chipid(struct lt9611c *lt9611c)
> +{
> + struct device *dev = lt9611c->dev;
> + u8 chipid[2];
> + int ret;
> +
> + ret = regmap_write(lt9611c->regmap, 0xe0ee, 0x01);
> + if (ret)
> + return ret;
> +
> + ret = regmap_bulk_read(lt9611c->regmap, 0xe100, chipid, 2);
> + if (ret)
> + return ret;
> +
> + if (chipid[0] != 0x23 || chipid[1] != 0x06) {
> + dev_err(dev, "ChipID: 0x%02x 0x%02x\n", chipid[0], chipid[1]);
> + return -ENODEV;
> + }
> +
> + return 0;
> +}
> +
> +static ssize_t lt9611c_firmware_store(struct device *dev, struct device_attribute *attr,
> + const char *buf, size_t len)
> +{
> + struct lt9611c *lt9611c = dev_get_drvdata(dev);
> + int ret;
> +
> + lt9611c_lock(lt9611c);
> +
> + ret = lt9611c_firmware_upgrade(lt9611c);
> + if (ret < 0) {
> + dev_err(dev, "upgrade failure\n");
> + goto out;
> + }
> + lt9611c_reset(lt9611c);
> + ret = lt9611c_upgrade_result(lt9611c);
> + if (ret < 0)
> + goto out;
> +
> +out:
> + lt9611c_unlock(lt9611c);
> + lt9611c_reset(lt9611c);
> + if (lt9611c->fw) {
> + release_firmware(lt9611c->fw);
> + lt9611c->fw = NULL;
> + }
> +
> + return ret < 0 ? ret : len;
> +}
> +
> +static ssize_t lt9611c_firmware_show(struct device *dev, struct device_attribute *attr, char *buf)
> +{
> + struct lt9611c *lt9611c = dev_get_drvdata(dev);
> +
> + return sysfs_emit(buf, "0x%04x\n", lt9611c->fw_version);
> +}
> +
> +static DEVICE_ATTR_RW(lt9611c_firmware);
> +
> +static struct attribute *lt9611c_attrs[] = {
> + &dev_attr_lt9611c_firmware.attr,
> + NULL,
> +};
> +
> +static const struct attribute_group lt9611c_attr_group = {
> + .attrs = lt9611c_attrs,
> +};
> +
> +static const struct attribute_group *lt9611c_attr_groups[] = {
> + &lt9611c_attr_group,
> + NULL,
> +};
> +
> +static int lt9611c_probe(struct i2c_client *client)
> +{
> + const struct i2c_device_id *id = i2c_client_get_device_id(client);
> + struct lt9611c *lt9611c;
> + struct device *dev = &client->dev;
> + bool fw_updated = false;
> + int ret;
> +
> + crc8_populate_msb(lt9611c_crc8_table, LT9611C_CRC_POLYNOMIAL);
> +
> + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
> + dev_err(dev, "device doesn't support I2C\n");
> + return -ENODEV;
> + }
> +
> + lt9611c = devm_drm_bridge_alloc(dev, struct lt9611c, bridge, &lt9611c_bridge_funcs);
> + if (IS_ERR(lt9611c))
> + return PTR_ERR(lt9611c);
> +
> + lt9611c->dev = dev;
> + lt9611c->client = client;
> + lt9611c->chip_type = id->driver_data;
> + mutex_init(&lt9611c->ocm_lock);
> +
> + lt9611c->regmap = devm_regmap_init_i2c(client, &lt9611c_regmap_config);
> + if (IS_ERR(lt9611c->regmap)) {
> + dev_err(dev, "regmap i2c init failed\n");
> + return PTR_ERR(lt9611c->regmap);
> + }
> +
> + ret = lt9611c_parse_dt(dev, lt9611c);
> + if (ret) {
> + dev_err(dev, "failed to parse device tree\n");
> + return ret;
> + }
> +
> + ret = lt9611c_gpio_init(lt9611c);
> + if (ret < 0)
> + goto err_of_put;
> +
> + ret = lt9611c_regulator_init(lt9611c);
> + if (ret < 0)
> + goto err_of_put;
> +
> + ret = lt9611c_regulator_enable(lt9611c);
> + if (ret)
> + goto err_of_put;
> +
> + lt9611c_reset(lt9611c);
> +
> + lt9611c_lock(lt9611c);
> +
> + ret = lt9611c_read_chipid(lt9611c);
> + if (ret < 0) {
> + dev_err(dev, "failed to read chip id.\n");
> + lt9611c_unlock(lt9611c);
> + goto err_disable_regulators;
> + }
> +
> +retry:
> + ret = lt9611c_read_version(lt9611c);
> + if (ret < 0) {
> + dev_err(dev, "failed to read fw version\n");
> + lt9611c_unlock(lt9611c);
> + goto err_disable_regulators;
> +
> + } else if (ret == 0) {
> + if (!fw_updated) {
> + fw_updated = true;
> + ret = lt9611c_firmware_upgrade(lt9611c);
> + if (ret < 0) {
> + lt9611c_unlock(lt9611c);
> + goto err_disable_regulators;
> + }
> +
> + lt9611c_reset(lt9611c);
> +
> + ret = lt9611c_upgrade_result(lt9611c);
> + if (ret < 0) {
> + lt9611c_unlock(lt9611c);
> + goto err_disable_regulators;
> + }
> +
> + goto retry;
> +
> + } else {
> + dev_err(dev, "fw version 0x%04x, update failed\n", ret);
> + ret = -EOPNOTSUPP;
> + lt9611c_unlock(lt9611c);
> + goto err_disable_regulators;
> + }
> + }
> +
> + lt9611c_unlock(lt9611c);
> + lt9611c->fw_version = ret;
> +
> + dev_dbg(dev, "current version:0x%04x", lt9611c->fw_version);
> +
> + INIT_WORK(&lt9611c->work, lt9611c_hpd_work);
> +
> + ret = devm_request_threaded_irq(&client->dev, client->irq, NULL,
> + lt9611c_irq_thread_handler,
> + IRQF_TRIGGER_FALLING |
> + IRQF_ONESHOT |
> + IRQF_NO_AUTOEN,
> + "lt9611c", lt9611c);
> + if (ret) {
> + dev_err(dev, "failed to request irq\n");
> + goto err_disable_regulators;
> + }
> +
> + lt9611c->bridge.of_node = client->dev.of_node;
> + lt9611c->bridge.ops = DRM_BRIDGE_OP_DETECT |
> + DRM_BRIDGE_OP_EDID |
> + DRM_BRIDGE_OP_HPD |
> + DRM_BRIDGE_OP_HDMI_AUDIO;
> + lt9611c->bridge.type = DRM_MODE_CONNECTOR_HDMIA;
> +
> + lt9611c->bridge.hdmi_audio_dev = dev;
> + lt9611c->bridge.hdmi_audio_max_i2s_playback_channels = 8;
> + lt9611c->bridge.hdmi_audio_dai_port = 2;
> +
> + drm_bridge_add(&lt9611c->bridge);
> +
> + /* Attach primary DSI */
> + lt9611c->dsi0 = lt9611c_attach_dsi(lt9611c, lt9611c->dsi0_node);
> + if (IS_ERR(lt9611c->dsi0)) {
> + ret = PTR_ERR(lt9611c->dsi0);
> + goto err_remove_bridge;
> + }
> +
> + /* Attach secondary DSI, if specified */
> + if (lt9611c->dsi1_node) {
> + lt9611c->dsi1 = lt9611c_attach_dsi(lt9611c, lt9611c->dsi1_node);
> + if (IS_ERR(lt9611c->dsi1)) {
> + ret = PTR_ERR(lt9611c->dsi1);
> + goto err_remove_bridge;
> + }
> + }
> +
> + lt9611c->hdmi_connected = false;
> + i2c_set_clientdata(client, lt9611c);
> + enable_irq(client->irq);
> + lt9611c_reset(lt9611c);
> +
> + return 0;
> +
> +err_remove_bridge:
> + free_irq(client->irq, lt9611c);
> + cancel_work_sync(&lt9611c->work);
> + drm_bridge_remove(&lt9611c->bridge);
> +
> +err_disable_regulators:
> + regulator_bulk_disable(ARRAY_SIZE(lt9611c->supplies), lt9611c->supplies);
> +
> +err_of_put:
> + of_node_put(lt9611c->dsi1_node);
> + of_node_put(lt9611c->dsi0_node);
> + if (lt9611c->fw) {
> + release_firmware(lt9611c->fw);
> + lt9611c->fw = NULL;
> + }
> +
> + return ret;
> +}
> +
> +static void lt9611c_remove(struct i2c_client *client)
> +{
> + struct lt9611c *lt9611c = i2c_get_clientdata(client);
> +
> + free_irq(client->irq, lt9611c);
> + cancel_work_sync(&lt9611c->work);
> + drm_bridge_remove(&lt9611c->bridge);
> + mutex_destroy(&lt9611c->ocm_lock);
> + regulator_bulk_disable(ARRAY_SIZE(lt9611c->supplies), lt9611c->supplies);
> + of_node_put(lt9611c->dsi1_node);
> + of_node_put(lt9611c->dsi0_node);
> +}
> +
> +static int lt9611c_bridge_suspend(struct device *dev)
> +{
> + struct lt9611c *lt9611c = dev_get_drvdata(dev);
> + int ret;
> +
> + dev_dbg(lt9611c->dev, "suspend\n");
> + disable_irq(lt9611c->client->irq);
> + ret = lt9611c_regulator_disable(lt9611c);
> + gpiod_set_value_cansleep(lt9611c->reset_gpio, 0);
> +
> + return ret;
> +}
> +
> +static int lt9611c_bridge_resume(struct device *dev)
> +{
> + struct lt9611c *lt9611c = dev_get_drvdata(dev);
> + int ret;
> +
> + ret = lt9611c_regulator_enable(lt9611c);
> + enable_irq(lt9611c->client->irq);
> + lt9611c_reset(lt9611c);
> + dev_dbg(lt9611c->dev, "resume\n");
> +
> + return ret;
> +}
> +
> +static const struct dev_pm_ops lt9611c_bridge_pm_ops = {
> + SET_SYSTEM_SLEEP_PM_OPS(lt9611c_bridge_suspend,
> + lt9611c_bridge_resume)
> +};
> +
> +static struct i2c_device_id lt9611c_id[] = {
> + /* chip_type */
> + { "lontium,lt9611c", 0 },
> + { "lontium,lt9611ex", 1 },
> + { "lontium,lt9611uxd", 2 },
> + { /* sentinel */ }
> +};
> +
> +static const struct of_device_id lt9611c_match_table[] = {
> + { .compatible = "lontium,lt9611c" },
> + { .compatible = "lontium,lt9611ex" },
> + { .compatible = "lontium,lt9611uxd" },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, lt9611c_match_table);
> +
> +static struct i2c_driver lt9611c_driver = {
> + .driver = {
> + .name = "lt9611c",
> + .of_match_table = lt9611c_match_table,
> + .pm = &lt9611c_bridge_pm_ops,
> + .dev_groups = lt9611c_attr_groups,
> + },
> + .probe = lt9611c_probe,
> + .remove = lt9611c_remove,
> + .id_table = lt9611c_id,
> +};
> +module_i2c_driver(lt9611c_driver);
> +
> +MODULE_AUTHOR("SunYun Yang <syyang@lontium.com>");
> +MODULE_DESCRIPTION("Lontium lt9611c mipi-dsi to hdmi driver");

MIPI, DSI, HDMI

> +MODULE_LICENSE("GPL v2");

I think, checkpatch.pl should have flagged this.

> +
> --
> 2.34.1
>

--
With best wishes
Dmitry