This patchset adds support for the I2C controller embedded in STM32F4xx SoC. It enables I2C transfer in interrupt mode with Standard-mode and Fast-mode bus speed. Changes since v9: - Fix minor typo in some comments - Add some comments to explain how the driver check TRISE and CCR value have no chance of overflow Changes since v8: - Rework I2C Clock Control Register computation (Uwe) - Save register accesses as often as possible (Uwe) - Don't use mask before saving rx buffer (Uwe) - Add more comments to explain hardware way of working (Uwe) - Rename stm32f4_i2c_handle_rx_btf function by stm32f4_i2c_handle_rx_done (Uwe) - Set/Clear Ack position bit during address match phase Changes since v7: - Remove unneeded parenthesis in some macro definitions (Uwe) - Fix some typo (s/KhzkHZ, s/PEC/POC) (Uwe) - Fix alignment issues in some structures declaration (Uwe) - Clarify comments to argue i2c_timing values chosen (Uwe) - Raise an error if parent clk rate is out of scope during I2C hw config (Uwe) - Use dev_dbg instead of dev_err message when I2C bus is busy (Uwe) - Add more comments about stuff done by stm32f4_i2c_handle_rx_btf() (Uwe) - Simplify stm32f4_i2c_isr_error() routine implementation by removing possible status checking (Uwe) - Rework stm32f4_i2c_isr_error() routine by removing the loop to check which status occured (Uwe) - Add open-drain property for SCL pins (Uwe) - Rework unneeded mul_ccr field from i2c_timing structure - Remove min_ccr field from i2c_timing structure as default scl_period is chosen to have a correct minimal ccr value - Execute hw_config once during probe - Remove soft_reset after an I2C error as all errors are now handled and hw_config is done once during probe - Generate STOP by software when Acknowledge failure occurs - Set the max speed mode for I2C pins - Add bias-disable property for I2C pins - Use intrinsic limitation of APB bus to set I2C max input clk Changes since v6: - Add commit message for the patches in defconfig, .dtsi and .dts files (Alex) - Order I2C instance base address in .dtsi file (Alex) - Add commit message for the patch in stm32429i-eval.dts (Alex) - Add link to the STM32F4 Soc ref manual where I2C device is described (Uwe) - Use more usal way to define constants with several lines (Uwe) - Remove rate variable from stm32f4_i2c_timings as it is not used (Uwe) - Remove irq variable from stm32f4_i2c_dev struct are they are only needed during probe (Uwe) - Add comment from datasheet to explain stm32f4_i2c_timings values (Uwe) - Rework i2c soft_reset implementation (Uwe) - Replace "it" by "irq" as it is a more usual abbreviation for interrupt (Uwe) - Add comment from datasheet to explain periph clk freq calculation (Uwe) - Use DIV_ROUND_UP instead of plain division when required (Uwe) - Add comment from datasheet to explain timing rise calculation (Uwe) - Rework timing rise calculation by using shorter computation (Uwe) - Remove (u8) cast when reading I2C data register (Uwe) - Rework isr_event routine to handle several events during one call of the routine (Uwe) - Precise which type of irq is failed when a irq request error occurs (Uwe) - Use devm_request_irq() instead of devm_request_threaded_irq() to avoid spurious evt irq when clearing status registers in threaded context Changes since v5: - Change commit header from "ARM: dts:" to "ARM: dts: stm32:" (Alex) - Change commit header from "ARM: configs:" to "ARM: configs: stm32:" (Alex) - Fix warnings due to variable set but unused (Wolfram) - Remove double space in Kconfig (Wolfram) - Fix warning due to bad type parameter when using clamp() function (build-bot) Changes since v4: - Use clamp() function to use a value in a given range as it was missed in V4 Changes since v3 after Wolfram's review: - Add COMPILE_TEST flag in Kconfig - Use correct driver name in Kconfig i.e i2c-stm32f4 instead of i2c-st - Use more comprehensible name stm32f4_i2c_msg for client specific data - Don't store reset control node as just needed in probe - Use clamp() function to test value between 2 ranges - Use new "i2c_8bit_addr_from_msg() function to build I2C address - Don't write error messages for timeout - Remove error message when i2c_add_adapter() fails as it is already handled by the i2c core driver Changes since v2: - remove interrupt configuration management from DT - remove FIFO configuration management from DT except threshold as it is very hard to handle it in the driver due to many possible combinations according to burst and bus width - update DMA client message in DT documentation file - specify the order to be used to set per-channel DMA interrupts in the DT - remove unused enumerations for channel and request ids - keep as soon as possible 80 lines char for more readability - replace unsigned int by u32 - return error if burst is not supported in stm32_dma_get_burst() - return error if bus_width is not supported in stm32_dma_get_width() - add FIFO configuration management inside the driver except for threshold - add interrupt configuration management inside the driver - rework stm32_dma_chan_irq() to handle error interrupt in one way - rework stm32_dma_set_xfer_param() to be easier to read - update stm32_dma_tx_status() to always return status from dma_cookie_status() - disable clk if we don't manage to stop the DMA channel during channel resources allocation - set driver as built-in as DMA will be required by other built-in driver Changes since v1: - use compatible st,stm32f4-i2c instead of st,i2c-stm32f4 (Rob) - fix typo s/enmpty/empty (Maxime) - use one function to handle TX fifo empty and byte xfer finished IT (Maxime) - set duty cycle in timing struct in Fast mode - Rework clock management (call prepare/unprepare at probe and remove, call clk_enable/clk_disable for each I2C transfer) M'boumba Cedric Madianga (5): dt-bindings: Document the STM32 I2C bindings i2c: Add STM32F4 I2C driver ARM: dts: stm32: Add I2C1 support for STM32F429 SoC ARM: dts: stm32: Add I2C1 support for STM32429 eval board ARM: configs: stm32: Add I2C support for STM32 defconfig .../devicetree/bindings/i2c/i2c-stm32.txt | 33 + arch/arm/boot/dts/stm32429i-eval.dts | 6 + arch/arm/boot/dts/stm32f429.dtsi | 23 + arch/arm/configs/stm32_defconfig | 3 + drivers/i2c/busses/Kconfig | 10 + drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-stm32f4.c | 897 +++++++++++++++++++++ 7 files changed, 973 insertions(+) create mode 100644 Documentation/devicetree/bindings/i2c/i2c-stm32.txt create mode 100644 drivers/i2c/busses/i2c-stm32f4.c -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
