[PATCH v9 0/2] Subject: Add Lontium LT9611C(EX/UXD) MIPI DSI to HDMI driver
[email protected] Tue, 04 Aug 2026 18:10:13 +0530
| Newsgroups | gmane.linux.drivers.devicetree,gmane.comp.video.dri.devel,gmane.linux.kernel |
|---|---|
| Message-ID | <[email protected]> |
This series introduces:
- A device tree binding YAML file describing the hardware
- A new DRM bridge driver implementing the basic functionality
LT9611C(EX/UXD) is an I2C-controlled chip that Receiver signal/dual port
mipi dsi and output hdmi, differences in hardware features:
- LT9611C: supports 1-port mipi dsi to hdmi 1.4
- LT9611EX: supports 2-port mipi dsi to hdmi 1.4
- LT9611UXD: supports 2-port mipi dsi to hdmi 1.4/2.0
Changes in v9:
- Use regmap_bulk_write for 4-byte header write in read_write_flow
- Replace while(1) loop with read_poll_timeout in lt9611c_block_erase; read_flash_reg_status now returns unsigned int
- Fix unchecked regmap_read in lt9611c_upgrade_result; return -EIO on CRC mismatch
- Add struct lt9611c_chip_data with chip_type and max_tmds_rate; fix i2c_device_id table driver_data to use chip data pointers
- Use put_unaligned_be16() to replace manual high/low byte splits in lt9611c_video_setup
- Extract lt9611c_write_infoframe() and lt9611c_clear_infoframe() helpers; consolidate 6 infoframe functions into 2 helpers
- Remove lt9611c_hdmi_audio_startup and its bridge_funcs entry
- Remove hpd_enable callback from bridge_funcs
- Fix scoped_guard(mutex) deadlock in audio_prepare: release lock before calling drm_atomic_helper_connector_hdmi_update_audio_infoframe()
- Fix probe order: lt9611c_reset() before enable_irq()
- Fix remove(): remove disable_irq() (IRQ is devm_request_threaded_irq-managed)
- Fix bridge_suspend() unwind: on regulator_bulk_disable failure, de-assert reset and re-enable IRQ
- Move devm_drm_bridge_add to after both DSI attaches; remove cancel_work_sync from err_remove_bridge label
- Move request_firmware outside mcu_lock in lt9611c_firmware_upgrade; lock only wraps hardware access
- Re-read lt9611c->fw_version after successful firmware_store upgrade
- Rename ocm_lock to mcu_lock throughout
- Use goto err_put_dsi1 to eliminate duplicate DSI cleanup in probe error path
- Fix mcu_lock comment to correctly describe what it protects
- dt-binding: add if:then: block to disallow port@1 when compatible is lontium,lt9611c
- Rename sysfs ABI doc to sysfs-driver-lontium; rename sysfs attribute from lt9611c_firmware to firmware
- Kconfig: add I2C to depends on to satisfy REGMAP_I2C dependency
- Link to v8: https://lore.kernel.org/lkml/20260728-lt9611c-v7-v8-0-bda216bfaf37-5oFBVzJwu8Ry9aJCnZT0Uw@public.gmane.org/
Changes in v8:
- Refactor lt9611c_read_write_flow() to take a struct lt9611c_cmd parameter with an embedded struct lt9611c_cmd_hdr (func,
type, seq, sep) and optional data payload, eliminating raw byte arrays at call sites
- Add LT9611C_CMD_HDR_SIZE, LT9611C_EDID_BUF_SIZE constants to replace magic numbers
- Use container_of_const() in bridge_to_lt9611c_const()
- Remove obvious /*read only*/ comment
- Use unsigned long cast instead of uintptr_t for chip type initialization
- Replace memset + memcpy with memcpy + memset for CRC buffer preparation
- Add ABI documentation for lt9611c_firmware sysfs attribute
- Fix Kconfig help text to proper prose within line limits
- Add disable_irq() before cancel_work_sync() in lt9611c_remove()
- Add cancel_work_sync() in lt9611c_bridge_suspend()
- Inline lt9611c_gpio_init() into probe
- Use of_drm_get_bridge_by_endpoint() instead of drm_of_find_panel_or_bridge() + drm_bridge_get()
- Return error if LT9611C (single DSI only) is configured with dual DSI in device tree
- Move HPD status read_write_flow call from IRQ handler to lt9611c_hpd_work workqueue
- Removed second lt9611_reset call from probe as not needed
- Add struct lt9611c_rsp symmetric to struct lt9611c_cmd — both embed struct lt9611c_cmd_hdr
- Link to v7: https://lore.kernel.org/lkml/20260716-lt9611c-v7-v7-0-7553a14735fc-5oFBVzJwu8Ry9aJCnZT0Uw@public.gmane.org/
Changes in v7:
- Use i2c_get_match_data() for chip type initialization
- Implement hdmi_write_hdmi_infoframe/hdmi_clear_hdmi_infoframe
- Use drm_atomic_commit in bridge callbacks
- Removing redundant lt9611c_reset() call and cleanup in probe error
path
- Populate bridge.vendor and bridge.product
- implement hpd_enable callback
- fix DT parsing and bridge refcount
- Removed pre_enable and post_disable callbacks, it was affecting hpd
as regulator was disabled
- Changed reset gpio enablement and lt9611c_reset api.
- Link to v6: https://lore.kernel.org/all/20260508134009.4582-1-syyang-Sflc69xqkl5BDgjK7y7TUQ@public.gmane.org/
Changes in v6:
- dt-binding:
1. sorted the compatible list alphabetically. [Dmitry]
- Link to v5: https://lore.kernel.org/lkml/20260507024214.97708-1-syyang-Sflc69xqkl5BDgjK7y7TUQ@public.gmane.org/
Changes in v5:
- drm/bridge:
1. use #define FW_FILE "Lontium/lt9611c_fw.bin" to match linux-firmware [Dmitry]
2. add atomic state management
- Link to v4: https://lore.kernel.org/lkml/20260506095100.78998-1-syyang-Sflc69xqkl5BDgjK7y7TUQ@public.gmane.org/
Changes in v4:
- dt-binding:
1. fix commit message [Krzysztof]
- drm/bridge:
1. use lt9611c_fw.bin [Dmitry]
3. use enum lt9611_chip_type
4. remove *fw from the lt9611c struct
5. use read_poll_timeout and -ETIMEDOUT
6. replace mutex_lock with guard(mutex) in some places
7. switch to ARRAY_SIZE instead of specifying lengths directly
8. use dev_err_probe
9. add clear functions for AVI and audio infoframes
10. add DRM_BRIDGE_OP_HDMI and remove .hpd_notify
11. replace "GPL v2" with "GPL"
- Link to v3: https://lore.kernel.org/lkml/20260420061644.1251070-1-syyang-Sflc69xqkl5BDgjK7y7TUQ@public.gmane.org/
Changes in v3:
- dt-binding:
1. lt9611c(ex/uxd) content merged into lontium,lt9611.yaml
- drm/bridge:
1. Drop the licence text, only use SPDX header
2. Sort the headers
3. Use library functions for crc8
4. Use paged writes as implemented for LT9611C(EX/UXD)
5. Use HDMI audio helpers
6. Replace devm_kzalloc with devm_drm_bridge_alloc
7. Remove extra kthread
- Link to v1: https://lore.kernel.org/lkml/20250903123825.1721443-1-syyang-Sflc69xqkl5BDgjK7y7TUQ@public.gmane.org/
Changes in v2:
1. Forget modify code, operation error, Please disregard this submit.
Changes in v1:
- dt-binding:
1. Submit the first version of the code.
- drm/bridge:
1. Submit the first version of the code.
Signed-off-by: Mohit Dsor <[email protected]>
---
---
Sunyun Yang (2):
dt-bindings: bridge: Add Lontium LT9611C(EX/UXD) MIPI DSI to HDMI driver
drm/bridge: Add Lontium LT9611C(EX/UXD) MIPI DSI to HDMI driver
Documentation/ABI/testing/sysfs-lontium-firmware | 10 +
.../bindings/display/bridge/lontium,lt9611.yaml | 18 +-
drivers/gpu/drm/bridge/Kconfig | 18 +
drivers/gpu/drm/bridge/Makefile | 1 +
drivers/gpu/drm/bridge/lontium-lt9611c.c | 1263 ++++++++++++++++++++
5 files changed, 1308 insertions(+), 2 deletions(-)
---
base-commit: 34e27b90552acf21bd73aac395667c8aae6da480
change-id: 20260708-lt9611c-v7-ff76b2d1bf5f
Best regards,
--
Mohit Dsor <[email protected]>