[PATCH v10 0/2] Subject: Add Lontium LT9611C(EX/UXD) MIPI DSI to HDMI driver

[mohit.dsor@oss.qualcomm.com]

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 v10:
- Fix lt9611c_block_erase: check return value of read_poll_timeout to avoid writing to un-erased flash
- Fix NULL dereference: check i2c_get_match_data() return value before dereferencing
- Fix irq handler: return IRQ_NONE when BIT(0) is not set
- Fix devm_drm_bridge_add: check and propagate error return
- Fix use-after-free in remove: call disable_irq() before cancel_work_sync()
- Fix bridge/regulator ordering in remove: use drm_bridge_add/drm_bridge_remove explicitly so bridge is unregistered before regulators are disabled
- Promote firmware upgrade success log from dev_dbg to dev_info
- Link to v9: https://lore.kernel.org/lkml/20260804-lt9611c-v7-v9-0-3423a76856d3@oss.qualcomm.com/

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@oss.qualcomm.com/

  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@oss.qualcomm.com/

  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@lontium.com/

  Changes in v6:
  - dt-binding:
   1. sorted the compatible list alphabetically.                     [Dmitry]
  - Link to v5: https://lore.kernel.org/lkml/20260507024214.97708-1-syyang@lontium.com/

  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@lontium.com/

  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@lontium.com/

  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@lontium.com/

  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 <mohit.dsor@oss.qualcomm.com>
---
To: Andrzej Hajda <andrzej.hajda@intel.com>
To: Neil Armstrong <neil.armstrong@linaro.org>
To: Robert Foss <rfoss@kernel.org>
To: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
To: Jonas Karlman <jonas@kwiboo.se>
To: Jernej Skrabec <jernej.skrabec@gmail.com>
To: Luca Ceresoli <luca.ceresoli@bootlin.com>
To: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
To: Maxime Ripard <mripard@kernel.org>
To: Thomas Zimmermann <tzimmermann@suse.de>
To: David Airlie <airlied@gmail.com>
To: Simona Vetter <simona@ffwll.ch>
To: Rob Herring <robh@kernel.org>
To: Krzysztof Kozlowski <krzk+dt@kernel.org>
To: Conor Dooley <conor+dt@kernel.org>
To: Vinod Koul <vkoul@kernel.org>
Cc: dri-devel@lists.freedesktop.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org

---
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           | 1283 ++++++++++++++++++++
 5 files changed, 1328 insertions(+), 2 deletions(-)
---
base-commit: 34e27b90552acf21bd73aac395667c8aae6da480
change-id: 20260708-lt9611c-v7-ff76b2d1bf5f

Best regards,
--  
Mohit Dsor <mohit.dsor@oss.qualcomm.com>