ti,cc13xx-cc26xx-timer-pwm

Description

TI SimpleLink CC13xx/CC26xx GPT timer PWM Controller Node

To configure a PWM node, you first need to define a board overlay with a
pinctrl configuration for the pin on which the PWM signal should be present:

  &pinctrl {
    gpt0_pwm: gpt0_pwm {
      pinmux = <25 IOC_PORT_MCU_PORT_EVENT1>;
      bias-disable;
      drive-strength = <8>; /* in mA, can be 2, 4 or 8 */
    };
  };

Please be aware that the port event depends on the GPT instance chosen. The
following port events must be used for PWM:
  - GPT0: IOC_PORT_MCU_PORT_EVENT1
  - GPT1: IOC_PORT_MCU_PORT_EVENT3
  - GPT2: IOC_PORT_MCU_PORT_EVENT5
  - GPT3: IOC_PORT_MCU_PORT_EVENT7

Be careful not to choose a pin that is already in use on your board, this
might irreversible damage to your board as the given pin will be configured as
output and actively driven by the PWM driver.

Then enable the corresponding timer and PWM nodes and add a reference to the
pinctrl entry:

  &gpt0 {
    status = "okay";
  };

  &pwm0 {
    status = "okay";
    pinctrl-0 = <&gpt0_pwm>;
    pinctrl-names = "default";
  };

Now you can programmatically enable the PWM signal in your code:

  static const struct device *pwm = DEVICE_DT_GET(DT_NODELABEL(pwm0));

  int init_pwm(void)
  {
    uint32_t pwm_period_ns, pwm_pulse_ns;
    uint32_t pwm_duty_percent = 50U;
    uint32_t pwm_frequency = 1000U; /* 1kHz */

    if (!device_is_ready(pwm)) {
      LOG_ERR("Error: PWM device %s is not ready\n", pwm->name);
      return -ENODEV;
    }

    pwm_period_ns = NSEC_PER_SEC / pwm_frequency;
    pwm_pulse_ns = (pwm_duty_percent * pwm_period_ns) / 100;

    return pwm_set(pwm, 0, pwm_period_ns, pwm_pulse_ns, 0);
  }

Properties

Properties not inherited from the base binding file.

Name	Type	Details
`#pwm-cells`	`int`	Number of items to expect in a pwm specifier This property is required.
`pinctrl-0`	`phandles`	Pin configuration/s for the first state. Content is specific to the selected pin controller driver implementation. This property is required.
`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.
`pinctrl-names`	`string-array`	Names for the provided states. The number of names needs to match the number of states.

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 “ti,cc13xx-cc26xx-timer-pwm” compatible.

Name	Type	Details
`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.
`power-domain`	`phandle`	Power domain the device belongs to. The device will be notified when the power domain it belongs to is either suspended or resumed.
`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.
`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`	`array`	register space See Important properties for more information.
`reg-names`	`string-array`	name of each register space
`interrupts`	`array`	interrupts for device See Important properties for more information.
`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
`#address-cells`	`int`	number of address cells in reg property
`#size-cells`	`int`	number of size cells in reg property
`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
`zephyr,deferred-init`	`boolean`	Do not initialize device automatically on boot. Device should be manually initialized using device_init().

Specifier cell names

pwm cells: channel, period, flags