linux_dsm_epyc7002/Documentation/devicetree/bindings/mfd/stm32-timers.txt
Fabrice Gasnier acc8e22f5d dt-bindings: mfd: stm32-timers: Add support for dmas
Add support for DMAs to STM32 timers. STM32 Timers can support up to 7
dma requests: up to 4 channels, update, compare and trigger.
DMAs may be used to transfer data from pwm capture for instance.
DMA support is made optional, PWM capture support is also an option.
This is much more wise system-wide to avoid shortage on DMA request
lines as there's significant amount of timer instances that can
request up to 7 channels.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2018-05-16 11:13:13 +01:00

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STM32 Timers driver bindings
This IP provides 3 types of timer along with PWM functionality:
- advanced-control timers consist of a 16-bit auto-reload counter driven by a programmable
prescaler, break input feature, PWM outputs and complementary PWM ouputs channels.
- general-purpose timers consist of a 16-bit or 32-bit auto-reload counter driven by a
programmable prescaler and PWM outputs.
- basic timers consist of a 16-bit auto-reload counter driven by a programmable prescaler.
Required parameters:
- compatible: must be "st,stm32-timers"
- reg: Physical base address and length of the controller's
registers.
- clock-names: Set to "int".
- clocks: Phandle to the clock used by the timer module.
For Clk properties, please refer to ../clock/clock-bindings.txt
Optional parameters:
- resets: Phandle to the parent reset controller.
See ../reset/st,stm32-rcc.txt
- dmas: List of phandle to dma channels that can be used for
this timer instance. There may be up to 7 dma channels.
- dma-names: List of dma names. Must match 'dmas' property. Valid
names are: "ch1", "ch2", "ch3", "ch4", "up", "trig",
"com".
Optional subnodes:
- pwm: See ../pwm/pwm-stm32.txt
- timer: See ../iio/timer/stm32-timer-trigger.txt
Example:
timers@40010000 {
#address-cells = <1>;
#size-cells = <0>;
compatible = "st,stm32-timers";
reg = <0x40010000 0x400>;
clocks = <&rcc 0 160>;
clock-names = "int";
pwm {
compatible = "st,stm32-pwm";
pinctrl-0 = <&pwm1_pins>;
pinctrl-names = "default";
};
timer@0 {
compatible = "st,stm32-timer-trigger";
reg = <0>;
};
};
Example with all dmas:
timer@40010000 {
...
dmas = <&dmamux1 11 0x400 0x0>,
<&dmamux1 12 0x400 0x0>,
<&dmamux1 13 0x400 0x0>,
<&dmamux1 14 0x400 0x0>,
<&dmamux1 15 0x400 0x0>,
<&dmamux1 16 0x400 0x0>,
<&dmamux1 17 0x400 0x0>;
dma-names = "ch1", "ch2", "ch3", "ch4", "up", "trig", "com";
...
child nodes...
};