pwm: fsl-ftm: Document 'big-endian' property

The same FTM PWM device can have a different endianness on different
SoCs. The device tree provides a property to describing this so that an
operating system device driver can handle all variants of the device.
Refer to the table below for the endianness of the FTM PWM block as
integrated into the existing SoCs:

	SoC     | FTM-PWM endianness
	--------+-------------------
	Vybrid  | LE
	LS1     | BE
	LS2     | LE

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This commit is contained in:
Xiubo Li 2014-08-19 12:38:03 +08:00 committed by Thierry Reding
parent 42fa98a9c3
commit a535e2e0de
1 changed files with 18 additions and 1 deletions

View File

@ -1,5 +1,20 @@
Freescale FlexTimer Module (FTM) PWM controller
The same FTM PWM device can have a different endianness on different SoCs. The
device tree provides a property to describing this so that an operating system
device driver can handle all variants of the device. Refer to the table below
for the endianness of the FTM PWM block as integrated into the existing SoCs:
SoC | FTM-PWM endianness
--------+-------------------
Vybrid | LE
LS1 | BE
LS2 | LE
Please see ../regmap/regmap.txt for more detail about how to specify endian
modes in device tree.
Required properties:
- compatible: Should be "fsl,vf610-ftm-pwm".
- reg: Physical base address and length of the controller's registers
@ -16,7 +31,8 @@ Required properties:
- pinctrl-names: Must contain a "default" entry.
- pinctrl-NNN: One property must exist for each entry in pinctrl-names.
See pinctrl/pinctrl-bindings.txt for details of the property values.
- big-endian: Boolean property, required if the FTM PWM registers use a big-
endian rather than little-endian layout.
Example:
@ -32,4 +48,5 @@ pwm0: pwm@40038000 {
<&clks VF610_CLK_FTM0_EXT_FIX_EN>;
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_pwm0_1>;
big-endian;
};