dts: arm: xmc4xxx: Add extra pinctrl nodes for i2c

The existing i2c sda/slc pinctrl nodes serve as an input and output
for the USIC. This limits the number of pins that can be used for i2c
since the pin must be internally connected to both DOUT0 and DX0 signals
on the USIC (for the sda signal for example).

It is also possible to use separate pins to DOUT0 and DX0, but connect
the pins externally. Add these extra pinctrl nodes and document their
use in infineon,xmc4xxx-i2c.yaml.

Signed-off-by: Andriy Gelman <andriy.gelman@gmail.com>
This commit is contained in:
Andriy Gelman 2023-07-19 10:22:27 -04:00 committed by Carles Cufí
parent f345698108
commit 0913d092c9
3 changed files with 180 additions and 1 deletions

View file

@ -388,4 +388,41 @@
/omit-if-no-ref/ i2c_scl_p0_8_u0c0: i2c_scl_p0_8_u0c0 {
pinmux = <XMC4XXX_PINMUX_SET(0, 8, 2)>; /* USIC scl-src = DX1B */
};
/omit-if-no-ref/ i2c_sda_dx0_p0_4_u1c0: i2c_sda_dx0_p0_4_u1c0 {
pinmux = <XMC4XXX_PINMUX_SET(0, 4, 0)>; /* USIC sda-src = DX0A */
};
/omit-if-no-ref/ i2c_sda_dx0_p3_4_u2c1: i2c_sda_dx0_p3_4_u2c1 {
pinmux = <XMC4XXX_PINMUX_SET(3, 4, 0)>; /* USIC sda-src = DX0B */
};
/omit-if-no-ref/ i2c_sda_dx0_p0_0_u1c1: i2c_sda_dx0_p0_0_u1c1 {
pinmux = <XMC4XXX_PINMUX_SET(0, 0, 0)>; /* USIC sda-src = DX0D */
};
/omit-if-no-ref/ i2c_sda_dx0_p4_0_u2c1: i2c_sda_dx0_p4_0_u2c1 {
pinmux = <XMC4XXX_PINMUX_SET(4, 0, 0)>; /* USIC sda-src = DX0C */
};
/omit-if-no-ref/ i2c_sda_dx0_p2_15_u1c0: i2c_sda_dx0_p2_15_u1c0 {
pinmux = <XMC4XXX_PINMUX_SET(2, 15, 0)>; /* USIC sda-src = DX0C */
};
/omit-if-no-ref/ i2c_sda_dx0_p1_4_u0c0: i2c_sda_dx0_p1_4_u0c0 {
pinmux = <XMC4XXX_PINMUX_SET(1, 4, 0)>; /* USIC sda-src = DX0B */
};
/omit-if-no-ref/ i2c_sda_dx0_p2_2_u0c1: i2c_sda_dx0_p2_2_u0c1 {
pinmux = <XMC4XXX_PINMUX_SET(2, 2, 0)>; /* USIC sda-src = DX0A */
};
/omit-if-no-ref/ i2c_sda_dout0_p0_1_u1c1: i2c_sda_dout0_p0_1_u1c1 {
pinmux = <XMC4XXX_PINMUX_SET(0, 1, 2)>;
};
/omit-if-no-ref/ i2c_sda_dout0_p1_7_u0c0: i2c_sda_dout0_p1_7_u0c0 {
pinmux = <XMC4XXX_PINMUX_SET(1, 7, 2)>;
};
/omit-if-no-ref/ i2c_scl_dx1_p4_0_u1c1: i2c_scl_dx1_p4_0_u1c1 {
pinmux = <XMC4XXX_PINMUX_SET(4, 0, 0)>; /* USIC scl-src = DX1C */
};
/omit-if-no-ref/ i2c_scl_dout1_p1_6_u0c0: i2c_scl_dout1_p1_6_u0c0 {
pinmux = <XMC4XXX_PINMUX_SET(1, 6, 2)>;
};
/omit-if-no-ref/ i2c_scl_dout1_p1_10_u0c0: i2c_scl_dout1_p1_10_u0c0 {
pinmux = <XMC4XXX_PINMUX_SET(1, 10, 2)>;
};
};

View file

@ -900,4 +900,89 @@
/omit-if-no-ref/ pwm_out_p6_1_ccu81_ch6_high: pwm_out_p6_1_ccu81_ch6_high {
pinmux = <XMC4XXX_PINMUX_SET(6, 1, 3)>;
};
/omit-if-no-ref/ i2c_sda_dx0_p3_12_u2c1: i2c_sda_dx0_p3_12_u2c1 {
pinmux = <XMC4XXX_PINMUX_SET(3, 12, 0)>; /* USIC sda-src = DX0D */
};
/omit-if-no-ref/ i2c_sda_dx0_p4_0_u2c1: i2c_sda_dx0_p4_0_u2c1 {
pinmux = <XMC4XXX_PINMUX_SET(4, 0, 0)>; /* USIC sda-src = DX0C */
};
/omit-if-no-ref/ i2c_sda_dx0_p0_0_u1c1: i2c_sda_dx0_p0_0_u1c1 {
pinmux = <XMC4XXX_PINMUX_SET(0, 0, 0)>; /* USIC sda-src = DX0D */
};
/omit-if-no-ref/ i2c_sda_dx0_p4_6_u2c1: i2c_sda_dx0_p4_6_u2c1 {
pinmux = <XMC4XXX_PINMUX_SET(4, 6, 0)>; /* USIC sda-src = DX0E */
};
/omit-if-no-ref/ i2c_sda_dx0_p2_2_u0c1: i2c_sda_dx0_p2_2_u0c1 {
pinmux = <XMC4XXX_PINMUX_SET(2, 2, 0)>; /* USIC sda-src = DX0A */
};
/omit-if-no-ref/ i2c_sda_dx0_p6_3_u0c1: i2c_sda_dx0_p6_3_u0c1 {
pinmux = <XMC4XXX_PINMUX_SET(6, 3, 0)>; /* USIC sda-src = DX0C */
};
/omit-if-no-ref/ i2c_sda_dx0_p3_7_u2c0: i2c_sda_dx0_p3_7_u2c0 {
pinmux = <XMC4XXX_PINMUX_SET(3, 7, 0)>; /* USIC sda-src = DX0C */
};
/omit-if-no-ref/ i2c_sda_dx0_p3_14_u1c1: i2c_sda_dx0_p3_14_u1c1 {
pinmux = <XMC4XXX_PINMUX_SET(3, 14, 0)>; /* USIC sda-src = DX0B */
};
/omit-if-no-ref/ i2c_sda_dx0_p2_15_u1c0: i2c_sda_dx0_p2_15_u1c0 {
pinmux = <XMC4XXX_PINMUX_SET(2, 15, 0)>; /* USIC sda-src = DX0C */
};
/omit-if-no-ref/ i2c_sda_dx0_p0_4_u1c0: i2c_sda_dx0_p0_4_u1c0 {
pinmux = <XMC4XXX_PINMUX_SET(0, 4, 0)>; /* USIC sda-src = DX0A */
};
/omit-if-no-ref/ i2c_sda_dx0_p6_5_u2c0: i2c_sda_dx0_p6_5_u2c0 {
pinmux = <XMC4XXX_PINMUX_SET(6, 5, 0)>; /* USIC sda-src = DX0D */
};
/omit-if-no-ref/ i2c_sda_dx0_p1_14_u1c0: i2c_sda_dx0_p1_14_u1c0 {
pinmux = <XMC4XXX_PINMUX_SET(1, 14, 0)>; /* USIC sda-src = DX0E */
};
/omit-if-no-ref/ i2c_sda_dx0_p3_4_u2c1: i2c_sda_dx0_p3_4_u2c1 {
pinmux = <XMC4XXX_PINMUX_SET(3, 4, 0)>; /* USIC sda-src = DX0B */
};
/omit-if-no-ref/ i2c_sda_dx0_p1_4_u0c0: i2c_sda_dx0_p1_4_u0c0 {
pinmux = <XMC4XXX_PINMUX_SET(1, 4, 0)>; /* USIC sda-src = DX0B */
};
/omit-if-no-ref/ i2c_sda_dout0_p3_8_u2c0: i2c_sda_dout0_p3_8_u2c0 {
pinmux = <XMC4XXX_PINMUX_SET(3, 8, 1)>;
};
/omit-if-no-ref/ i2c_sda_dout0_p1_9_u1c1: i2c_sda_dout0_p1_9_u1c1 {
pinmux = <XMC4XXX_PINMUX_SET(1, 9, 4)>;
};
/omit-if-no-ref/ i2c_sda_dout0_p6_4_u0c1: i2c_sda_dout0_p6_4_u0c1 {
pinmux = <XMC4XXX_PINMUX_SET(6, 4, 2)>;
};
/omit-if-no-ref/ i2c_sda_dout0_p1_15_u1c0: i2c_sda_dout0_p1_15_u1c0 {
pinmux = <XMC4XXX_PINMUX_SET(1, 15, 4)>;
};
/omit-if-no-ref/ i2c_sda_dout0_p3_11_u2c1: i2c_sda_dout0_p3_11_u2c1 {
pinmux = <XMC4XXX_PINMUX_SET(3, 11, 1)>;
};
/omit-if-no-ref/ i2c_sda_dout0_p0_1_u1c1: i2c_sda_dout0_p0_1_u1c1 {
pinmux = <XMC4XXX_PINMUX_SET(0, 1, 2)>;
};
/omit-if-no-ref/ i2c_sda_dout0_p1_7_u0c0: i2c_sda_dout0_p1_7_u0c0 {
pinmux = <XMC4XXX_PINMUX_SET(1, 7, 2)>;
};
/omit-if-no-ref/ i2c_sda_dout0_p6_6_u2c0: i2c_sda_dout0_p6_6_u2c0 {
pinmux = <XMC4XXX_PINMUX_SET(6, 6, 1)>;
};
/omit-if-no-ref/ i2c_scl_dout1_p1_8_u1c1: i2c_scl_dout1_p1_8_u1c1 {
pinmux = <XMC4XXX_PINMUX_SET(1, 8, 4)>;
};
/omit-if-no-ref/ i2c_scl_dout1_p3_13_u2c1: i2c_scl_dout1_p3_13_u2c1 {
pinmux = <XMC4XXX_PINMUX_SET(3, 13, 1)>;
};
/omit-if-no-ref/ i2c_scl_dout1_p1_6_u0c0: i2c_scl_dout1_p1_6_u0c0 {
pinmux = <XMC4XXX_PINMUX_SET(1, 6, 2)>;
};
/omit-if-no-ref/ i2c_scl_dout1_p1_9_u0c0: i2c_scl_dout1_p1_9_u0c0 {
pinmux = <XMC4XXX_PINMUX_SET(1, 9, 1)>;
};
/omit-if-no-ref/ i2c_scl_dout1_p1_10_u0c0: i2c_scl_dout1_p1_10_u0c0 {
pinmux = <XMC4XXX_PINMUX_SET(1, 10, 2)>;
};
/omit-if-no-ref/ i2c_scl_dout1_p3_9_u2c0: i2c_scl_dout1_p3_9_u2c0 {
pinmux = <XMC4XXX_PINMUX_SET(3, 9, 1)>;
};
};

View file

@ -103,10 +103,67 @@ properties:
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: <signal>_p<port>_<pin>_<peripheral inst>
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";
};
required: true
pinctrl-names: