infineon,xmc4xxx-i2c

Vendor: Infineon Technologies

Note

An implementation of a driver matching this compatible is available in drivers/i2c/i2c_ifx_xmc4.c.

Description

These nodes are “i2c” bus nodes.

Infineon XMC4XXX I2C

This driver configures the USIC as an I2C device.

Example devicetree configuration with an adt7420 temperature sensor
connected on the bus:

&usic1ch1 {
    compatible = "infineon,xmc4xxx-i2c";
    status = "okay";

    pinctrl-0 = <&i2c_scl_p0_13_u1c1 &i2c_sda_p3_15_u1c1>;
    pinctrl-names = "default";
    scl-src = "DX1B";
    sda-src = "DX0A";
    interrupts = <94 1>;

    #address-cells = <1>;
    #size-cells = <0>;

    clock-frequency = <I2C_BITRATE_STANDARD>;
    adt7420@48 {
        compatible = "adi,adt7420";
        reg = <0x48>;
    };
};

The pinctrl nodes need to be configured as open-drain and
hwctrl should be disabled:

&i2c_scl_p0_13_u1c1 {
    drive-strength = "strong-sharp-edge";
    drive-open-drain;
    hwctrl = "disabled";
};

&i2c_sda_p3_15_u1c1 {
    drive-strength = "strong-soft-edge";
    drive-open-drain;
    hwctrl = "disabled";
};

Properties

Node specific properties

Properties not inherited from the base binding file.

Name

Type

Details

scl-src

string

 
Connects the I2C clock line (USIC DX1 input) to a specific GPIO pin.
The USIC DX1 input is a multiplexer which connects to different GPIO pins.
Refer to the XMC4XXX reference manual for the GPIO pin/mux mappings.

This property is required.

Legal values: 'DX1A', 'DX1B', 'DX1C', 'DX1D', 'DX1E', 'DX1F', 'DX1G'

sda-src

string

 
Connects the I2C data line (USIC DX0 input) to a specific GPIO pin.
The USIC DX0 input is a multiplexer which connects to different GPIO pins.
Refer to the XMC4XXX reference manual for the GPIO pin/mux mappings.

This property is required.

Legal values: 'DX0A', 'DX0B', 'DX0C', 'DX0D', 'DX0E', 'DX0F', 'DX0G'

pinctrl-0

phandles

 
PORT pin configuration for SCL, SDA signals.
We expect that the phandles will reference pinctrl nodes. These
nodes will have a nodelabel that matches the Infineon SoC Pinctrl
defines and have following
format: i2c_<signal>_p<port>_<pin>_<peripheral inst>

Examples:
  pinctrl-0 = <&i2c_scl_p5_2_u2c0 &i2c_sda_p5_0_u2c0>;

The pins should set to open-drain and hwctrl should be disabled.

&i2c_scl_p5_2_u2c0 {
    drive-strength = "strong-sharp-edge";
    drive-open-drain;
    hwctrl = "disabled";
};

In the above example, the pin is both an input and output (as is
required for I2C setup). It is internally connected to both DX0
and DOUT0 of USIC2 channel 0. (See XMC4700/4800 reference manual
page 18-110, Figure 18-50 for more details).
This limits the number of pins that can be used for the I2C module.

To get around this pin limitation, it is possible to use pins
that do not have this internal connection, and instead connect the
pins externally on the board.
For example, for the SDA line on USIC2 channel 0, P3.8 may be used
for DOUT0 and P6.5 for DX0. These type of pinctrl nodes will have
labels:
i2c_sda_dout0_p3_8_u2c0 and i2c_sda_dx0_p6_5_u2c0.
The generalized format is: i2c_<signal>_<type>_p<port>_<pin>_<peripheral inst>

An example for SCL and SDA signals on the xmc4700:
pinctrl-0 = <&i2c_sda_dout0_p3_8_u2c0 &i2c_sda_dx0_p6_5_u2c0
            &i2c_scl_dout1_p3_9_u2c0 &i2c_scl_p5_2_u2c0>;

Externally P3.8 should be connected to P6.5; P3.9 should be connected
to P5.2.

Note that any pins that do not have dout0/dx0 or dout1/dx1 can have either
function. Thus node i2c_scl_p5_0_u2c0 can be both dout1 and dx1.

For the pin configurations, the output pins (dout0 and dout1) should be set
to open-drain while the input pins (dx0 and dx1) should not include this setting.

&i2c_sda_dout0_p3_8_u2c0 {
    drive-strength = "strong-sharp-edge";
    drive-open-drain;
    hwctrl = "disabled";
};

&i2c_scl_dout1_p3_9_u2c0 {
    drive-strength = "strong-sharp-edge";
    drive-open-drain;
    hwctrl = "disabled";
};

&i2c_sda_dx0_p6_5_u2c0 {   /* will require USIC setting sda-src = DX0D */
    hwctrl = "disabled";
};

&i2c_scl_p5_2_u2c0 {  /* will require USIC scl-src = DX1A */
    hwctrl = "disabled";
};

This property is required.

pinctrl-names

string-array

 
Names for the provided states. The number of names needs to match the
number of states.

This property is required.

clock-frequency

int

 
Initial clock frequency in Hz

sq-size

int

 
Size of the submission queue for blocking requests

Default value: 4

cq-size

int

 
Size of the completion queue for blocking requests

Default value: 4

pinctrl-1

phandles

 
Pin configuration/s for the second state. See pinctrl-0.

pinctrl-2

phandles

 
Pin configuration/s for the third state. See pinctrl-0.

pinctrl-3

phandles

 
Pin configuration/s for the fourth state. See pinctrl-0.

pinctrl-4

phandles

 
Pin configuration/s for the fifth state. See pinctrl-0.

Deprecated node specific properties

Deprecated properties not inherited from the base binding file.

(None)

Base properties

Properties inherited from the base binding file, which defines common properties that may be set on many nodes. Not all of these may apply to the “infineon,xmc4xxx-i2c” compatible.

Name

Type

Details

reg

array

 
register space

This property is required.

See Important properties for more information.

interrupts

array

 
IRQ number and priority to use for interrupt driven by I2C.
Each USIC must use a certain interrupt range:
USIC0 = [84, 89]
USIC1 = [90, 95]
USIC2 = [96, 101]

This property is required.

See Important properties for more information.

#address-cells

int

 
number of address cells in reg property

This property is required.

Constant value: 1

#size-cells

int

 
number of size cells in reg property

This property is required.

status

string

 
indicates the operational status of a device

Legal values: 'ok', 'okay', 'disabled', 'reserved', 'fail', 'fail-sss'

See Important properties for more information.

compatible

string-array

 
compatible strings

This property is required.

See Important properties for more information.

reg-names

string-array

 
name of each register space

interrupts-extended

compound

 
extended interrupt specifier for device

interrupt-names

string-array

 
name of each interrupt

interrupt-parent

phandle

 
phandle to interrupt controller node

label

string

 
Human readable string describing the device (used as device_get_binding() argument)

See Important properties for more information.

This property is deprecated.

clocks

phandle-array

 
Clock gate information

clock-names

string-array

 
name of each clock

dmas

phandle-array

 
DMA channels specifiers

dma-names

string-array

 
Provided names of DMA channel specifiers

io-channels

phandle-array

 
IO channels specifiers

io-channel-names

string-array

 
Provided names of IO channel specifiers

mboxes

phandle-array

 
mailbox / IPM channels specifiers

mbox-names

string-array

 
Provided names of mailbox / IPM channel specifiers

power-domains

phandle-array

 
Power domain specifiers

power-domain-names

string-array

 
Provided names of power domain specifiers

#power-domain-cells

int

 
Number of cells in power-domains property

zephyr,deferred-init

boolean

 
Do not initialize device automatically on boot. Device should be manually
initialized using device_init().

wakeup-source

boolean

 
Property to identify that a device can be used as wake up source.

When this property is provided a specific flag is set into the
device that tells the system that the device is capable of
wake up the system.

Wake up capable devices are disabled (interruptions will not wake up
the system) by default but they can be enabled at runtime if necessary.

zephyr,pm-device-runtime-auto

boolean

 
Automatically configure the device for runtime power management after the
init function runs.

zephyr,disabling-power-states

phandles

 
List of power states that will disable this device power.