xref: /OK3568_Linux_fs/kernel/Documentation/devicetree/bindings/pwm/pwm-fsl-ftm.txt (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunFreescale FlexTimer Module (FTM) PWM controller
2*4882a593Smuzhiyun
3*4882a593SmuzhiyunThe same FTM PWM device can have a different endianness on different SoCs. The
4*4882a593Smuzhiyundevice tree provides a property to describing this so that an operating system
5*4882a593Smuzhiyundevice driver can handle all variants of the device. Refer to the table below
6*4882a593Smuzhiyunfor the endianness of the FTM PWM block as integrated into the existing SoCs:
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun	SoC     | FTM-PWM endianness
9*4882a593Smuzhiyun	--------+-------------------
10*4882a593Smuzhiyun	Vybrid  | LE
11*4882a593Smuzhiyun	LS1     | BE
12*4882a593Smuzhiyun	LS2     | LE
13*4882a593Smuzhiyun
14*4882a593SmuzhiyunPlease see ../regmap/regmap.txt for more detail about how to specify endian
15*4882a593Smuzhiyunmodes in device tree.
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun
18*4882a593SmuzhiyunRequired properties:
19*4882a593Smuzhiyun- compatible : should be "fsl,<soc>-ftm-pwm" and one of the following
20*4882a593Smuzhiyun   compatible strings:
21*4882a593Smuzhiyun  - "fsl,vf610-ftm-pwm" for PWM compatible with the one integrated on VF610
22*4882a593Smuzhiyun  - "fsl,imx8qm-ftm-pwm" for PWM compatible with the one integrated on i.MX8QM
23*4882a593Smuzhiyun- reg: Physical base address and length of the controller's registers
24*4882a593Smuzhiyun- #pwm-cells: Should be 3. See pwm.yaml in this directory for a description of
25*4882a593Smuzhiyun  the cells format.
26*4882a593Smuzhiyun- clock-names: Should include the following module clock source entries:
27*4882a593Smuzhiyun    "ftm_sys" (module clock, also can be used as counter clock),
28*4882a593Smuzhiyun    "ftm_ext" (external counter clock),
29*4882a593Smuzhiyun    "ftm_fix" (fixed counter clock),
30*4882a593Smuzhiyun    "ftm_cnt_clk_en" (external and fixed counter clock enable/disable).
31*4882a593Smuzhiyun- clocks: Must contain a phandle and clock specifier for each entry in
32*4882a593Smuzhiyun  clock-names, please see clock/clock-bindings.txt for details of the property
33*4882a593Smuzhiyun  values.
34*4882a593Smuzhiyun- pinctrl-names: Must contain a "default" entry.
35*4882a593Smuzhiyun- pinctrl-NNN: One property must exist for each entry in pinctrl-names.
36*4882a593Smuzhiyun  See pinctrl/pinctrl-bindings.txt for details of the property values.
37*4882a593Smuzhiyun- big-endian: Boolean property, required if the FTM PWM registers use a big-
38*4882a593Smuzhiyun  endian rather than little-endian layout.
39*4882a593Smuzhiyun
40*4882a593SmuzhiyunExample:
41*4882a593Smuzhiyun
42*4882a593Smuzhiyunpwm0: pwm@40038000 {
43*4882a593Smuzhiyun		compatible = "fsl,vf610-ftm-pwm";
44*4882a593Smuzhiyun		reg = <0x40038000 0x1000>;
45*4882a593Smuzhiyun		#pwm-cells = <3>;
46*4882a593Smuzhiyun		clock-names = "ftm_sys", "ftm_ext",
47*4882a593Smuzhiyun				"ftm_fix", "ftm_cnt_clk_en";
48*4882a593Smuzhiyun		clocks = <&clks VF610_CLK_FTM0>,
49*4882a593Smuzhiyun			<&clks VF610_CLK_FTM0_EXT_SEL>,
50*4882a593Smuzhiyun			<&clks VF610_CLK_FTM0_FIX_SEL>,
51*4882a593Smuzhiyun			<&clks VF610_CLK_FTM0_EXT_FIX_EN>;
52*4882a593Smuzhiyun		pinctrl-names = "default";
53*4882a593Smuzhiyun		pinctrl-0 = <&pinctrl_pwm0_1>;
54*4882a593Smuzhiyun		big-endian;
55*4882a593Smuzhiyun};
56