diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/devicetree/bindings/i2c/i2c-qcom-cci.txt | 92 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/i2c/i2c.txt | 69 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/i2c/st,stm32-i2c.yaml | 8 |
3 files changed, 138 insertions, 31 deletions
diff --git a/Documentation/devicetree/bindings/i2c/i2c-qcom-cci.txt b/Documentation/devicetree/bindings/i2c/i2c-qcom-cci.txt new file mode 100644 index 000000000000..c6668b7c66e6 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/i2c-qcom-cci.txt @@ -0,0 +1,92 @@ +Qualcomm Camera Control Interface (CCI) I2C controller + +PROPERTIES: + +- compatible: + Usage: required + Value type: <string> + Definition: must be one of: + "qcom,msm8916-cci" + "qcom,msm8996-cci" + "qcom,sdm845-cci" + +- reg + Usage: required + Value type: <prop-encoded-array> + Definition: base address CCI I2C controller and length of memory + mapped region. + +- interrupts: + Usage: required + Value type: <prop-encoded-array> + Definition: specifies the CCI I2C interrupt. The format of the + specifier is defined by the binding document describing + the node's interrupt parent. + +- clocks: + Usage: required + Value type: <prop-encoded-array> + Definition: a list of phandle, should contain an entry for each + entries in clock-names. + +- clock-names + Usage: required + Value type: <string> + Definition: a list of clock names, must include "cci" clock. + +- power-domains + Usage: required for "qcom,msm8996-cci" + Value type: <prop-encoded-array> + Definition: + +SUBNODES: + +The CCI provides I2C masters for one (msm8916) or two i2c busses (msm8996 and +sdm845), described as subdevices named "i2c-bus@0" and "i2c-bus@1". + +PROPERTIES: + +- reg: + Usage: required + Value type: <u32> + Definition: Index of the CCI bus/master + +- clock-frequency: + Usage: optional + Value type: <u32> + Definition: Desired I2C bus clock frequency in Hz, defaults to 100 + kHz if omitted. + +Example: + + cci@a0c000 { + compatible = "qcom,msm8996-cci"; + #address-cells = <1>; + #size-cells = <0>; + reg = <0xa0c000 0x1000>; + interrupts = <GIC_SPI 295 IRQ_TYPE_EDGE_RISING>; + clocks = <&mmcc MMSS_MMAGIC_AHB_CLK>, + <&mmcc CAMSS_TOP_AHB_CLK>, + <&mmcc CAMSS_CCI_AHB_CLK>, + <&mmcc CAMSS_CCI_CLK>, + <&mmcc CAMSS_AHB_CLK>; + clock-names = "mmss_mmagic_ahb", + "camss_top_ahb", + "cci_ahb", + "cci", + "camss_ahb"; + + i2c-bus@0 { + reg = <0>; + clock-frequency = <400000>; + #address-cells = <1>; + #size-cells = <0>; + }; + + i2c-bus@1 { + reg = <1>; + clock-frequency = <400000>; + #address-cells = <1>; + #size-cells = <0>; + }; + }; diff --git a/Documentation/devicetree/bindings/i2c/i2c.txt b/Documentation/devicetree/bindings/i2c/i2c.txt index 9a53df4243c6..7aff425c099b 100644 --- a/Documentation/devicetree/bindings/i2c/i2c.txt +++ b/Documentation/devicetree/bindings/i2c/i2c.txt @@ -2,32 +2,29 @@ Generic device tree bindings for I2C busses =========================================== This document describes generic bindings which can be used to describe I2C -busses in a device tree. +busses and their child devices in a device tree. -Required properties -------------------- +Required properties (per bus) +----------------------------- - #address-cells - should be <1>. Read more about addresses below. - #size-cells - should be <0>. -- compatible - name of I2C bus controller following generic names - recommended practice. +- compatible - name of I2C bus controller For other required properties e.g. to describe register sets, clocks, etc. check the binding documentation of the specific driver. The cells properties above define that an address of children of an I2C bus -are described by a single value. This is usually a 7 bit address. However, -flags can be attached to the address. I2C_TEN_BIT_ADDRESS is used to mark a 10 -bit address. It is needed to avoid the ambiguity between e.g. a 7 bit address -of 0x50 and a 10 bit address of 0x050 which, in theory, can be on the same bus. -Another flag is I2C_OWN_SLAVE_ADDRESS to mark addresses on which we listen to -be devices ourselves. +are described by a single value. -Optional properties -------------------- +Optional properties (per bus) +----------------------------- These properties may not be supported by all drivers. However, if a driver -wants to support one of the below features, it should adapt the bindings below. +wants to support one of the below features, it should adapt these bindings. + +- bus-supply + phandle to the regulator that provides power to SCL/SDA. - clock-frequency frequency of bus clock in Hz. @@ -73,31 +70,49 @@ wants to support one of the below features, it should adapt the bindings below. i2c bus clock frequency (clock-frequency). Specified in Hz. -- interrupts - interrupts used by the device. - -- interrupt-names - "irq", "wakeup" and "smbus_alert" names are recognized by I2C core, - other names are left to individual drivers. - -- host-notify - device uses SMBus host notify protocol instead of interrupt line. - - multi-master states that there is another master active on this bus. The OS can use this information to adapt power management to keep the arbitration awake all the time, for example. -- wakeup-source - device can be used as a wakeup source. +Required properties (per child device) +-------------------------------------- + +- compatible + name of I2C slave device - reg - I2C slave addresses + One or many I2C slave addresses. These are usually a 7 bit addresses. + However, flags can be attached to an address. I2C_TEN_BIT_ADDRESS is + used to mark a 10 bit address. It is needed to avoid the ambiguity + between e.g. a 7 bit address of 0x50 and a 10 bit address of 0x050 + which, in theory, can be on the same bus. + Another flag is I2C_OWN_SLAVE_ADDRESS to mark addresses on which we + listen to be devices ourselves. + +Optional properties (per child device) +-------------------------------------- + +These properties may not be supported by all drivers. However, if a driver +wants to support one of the below features, it should adapt these bindings. + +- host-notify + device uses SMBus host notify protocol instead of interrupt line. + +- interrupts + interrupts used by the device. + +- interrupt-names + "irq", "wakeup" and "smbus_alert" names are recognized by I2C core, + other names are left to individual drivers. - reg-names Names of map programmable addresses. It can contain any map needing another address than default one. +- wakeup-source + device can be used as a wakeup source. + Binding may contain optional "interrupts" property, describing interrupts used by the device. I2C core will assign "irq" interrupt (or the very first interrupt if not using interrupt names) as primary interrupt for the slave. diff --git a/Documentation/devicetree/bindings/i2c/st,stm32-i2c.yaml b/Documentation/devicetree/bindings/i2c/st,stm32-i2c.yaml index 900ec1ab6a47..b50a2f420b36 100644 --- a/Documentation/devicetree/bindings/i2c/st,stm32-i2c.yaml +++ b/Documentation/devicetree/bindings/i2c/st,stm32-i2c.yaml @@ -80,11 +80,11 @@ properties: clock-frequency: description: Desired I2C bus clock frequency in Hz. If not specified, the default 100 kHz frequency will be used. - For STM32F7, STM32H7 and STM32MP1 SoCs, Standard-mode, - Fast-mode and Fast-mode Plus are supported, possible - values are 100000, 400000 and 1000000. + For STM32F7, STM32H7 and STM32MP1 SoCs, if timing parameters + match, the bus clock frequency can be from 1Hz to 1MHz. default: 100000 - enum: [100000, 400000, 1000000] + minimum: 1 + maximum: 1000000 required: - compatible |