Hi all: This patch series adds support for the I2C module found on various Loongson systems with the Loongson-2K SoC or the Loongson LS7A bridge chip. For now, the I2C driver is suitable for DT-based or ACPI-based systems. I have tested on Loongson-3A5000LA+LS7A1000/LS7A2000, Loongson-2K1000LA and Loongson-2K0500. Thanks. Changes since V4: - patch (1/4) - Drop unneeded headers: of.h; - xxx_props -> xxx_properties. - patch (2/4) - Add interrupt headers to fix syntax error found by Rob. - patch (3/4) - Drop atmoic loop in ls2x_i2c_master_xfer(), The continuous I2C read/write test passes on the corresponding machine; - Define the corresponding bits in I2C_LS2X_CTR to avoid magic numbers; - dev_get_drvdata() is used to get ls2x_i2c_priv() in ls2x_i2c_suspend(); - i2c_add_adapter() -> devm_i2c_add_adapter(); - SET_SYSTEM_SLEEP_PM_OPS() -> DEFINE_RUNTIME_DEV_PM_OPS(); - Code formatting, such as alignment. Details: https://lore.kernel.org/all/Y4e%2F6KewuHjAluSZ@xxxxxxxxxxxxxxxxxx/ Changes since V3: - Addressed all review comments from v3 - Change the changelog text to make it clearer (1/5); - Fix some minor bugs, such as formatting issues (2/5); - Fix some formatting issues (3/5); - Deep refactoring of code for clarity (4/5). Details: https://lore.kernel.org/all/Y4S2cnlAm3YYvZ8E@xxxxxxxxxxxxxxxxxx/ Thanks to all for their suggestions. Changes since V2: - Addressed all review comments from v2 - Drop of_match_ptr() in i2c-gpio to avoid potential unused warnings (1/5); - Introduce i2c_gpio_get_props() function as the generic interface to get i2c-gpio props from DT or ACPI table (2/5); - Refact ls2x i2c code, similar to removing excessive goto tags (4/5). Thanks to Andy and Mika for their suggestions. Changes since V1: - Remove the function of getting the static i2c bus number from ACPI "_UID"; - Fix build warning from kernel test robot. Binbin Zhou (4): i2c: gpio: Add support on ACPI-based system dt-bindings: i2c: add Loongson LS2X I2C controller i2c: ls2x: Add driver for Loongson-2K/LS7A I2C controller LoongArch: Enable LS2X I2C in loongson3_defconfig .../bindings/i2c/loongson,ls2x-i2c.yaml | 51 +++ arch/loongarch/configs/loongson3_defconfig | 1 + drivers/i2c/busses/Kconfig | 11 + drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-gpio.c | 27 +- drivers/i2c/busses/i2c-ls2x.c | 379 ++++++++++++++++++ 6 files changed, 460 insertions(+), 10 deletions(-) create mode 100644 Documentation/devicetree/bindings/i2c/loongson,ls2x-i2c.yaml create mode 100644 drivers/i2c/busses/i2c-ls2x.c -- 2.31.1