linux/Documentation/devicetree/bindings/sound/davinci-mcasp-audio.txt

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Texas Instruments McASP controller
Required properties:
- compatible :
"ti,dm646x-mcasp-audio" : for DM646x platforms
"ti,da830-mcasp-audio" : for both DA830 & DA850 platforms
"ti,am33xx-mcasp-audio" : for AM33xx platforms (AM33xx, AM43xx, TI81xx)
"ti,dra7-mcasp-audio" : for DRA7xx platforms
- reg : Should contain reg specifiers for the entries in the reg-names property.
- reg-names : Should contain:
* "mpu" for the main registers (required). For compatibility with
existing software, it is recommended this is the first entry.
* "dat" for separate data port register access (optional).
- op-mode : I2S/DIT ops mode. 0 for I2S mode. 1 for DIT mode used for S/PDIF,
IEC60958-1, and AES-3 formats.
- tdm-slots : Slots for TDM operation. Indicates number of channels transmitted
or received over one serializer.
- serial-dir : A list of serializer configuration. Each entry is a number
indication for serializer pin direction.
(0 - INACTIVE, 1 - TX, 2 - RX)
- dmas: two element list of DMA controller phandles and DMA request line
ordered pairs.
- dma-names: identifier string for each DMA request line in the dmas property.
These strings correspond 1:1 with the ordered pairs in dmas. The dma
identifiers must be "rx" and "tx".
Optional properties:
- ti,hwmods : Must be "mcasp<n>", n is controller instance starting 0
- tx-num-evt : FIFO levels.
- rx-num-evt : FIFO levels.
- dismod : Specify the drive on TX pin during inactive slots
0 : 3-state
2 : logic low
3 : logic high
Defaults to 'logic low' when the property is not present
- sram-size-playback : size of sram to be allocated during playback
- sram-size-capture : size of sram to be allocated during capture
- interrupts : Interrupt numbers for McASP
- interrupt-names : Known interrupt names are "tx" and "rx"
- pinctrl-0: Should specify pin control group used for this controller.
- pinctrl-names: Should contain only one value - "default", for more details
please refer to pinctrl-bindings.txt
- fck_parent : Should contain a valid clock name which will be used as parent
for the McASP fck
- auxclk-fs-ratio: When McASP is bus master indicates the ratio between AUCLK
and FS rate if applicable:
AUCLK rate = auxclk-fs-ratio * FS rate
Optional GPIO support:
If any McASP pin need to be used as GPIO then the McASP node must have:
...
gpio-controller
#gpio-cells = <2>;
...
When requesting a GPIO, the first parameter is the PIN index in McASP_P*
registers.
For example to request the AXR2 pin of mcasp8:
function-gpios = <&mcasp8 2 0>;
Or to request the ACLKR pin of mcasp8:
function-gpios = <&mcasp8 29 0>;
For generic gpio information, please refer to bindings/gpio/gpio.txt
Example:
mcasp0: mcasp0@1d00000 {
compatible = "ti,da830-mcasp-audio";
reg = <0x100000 0x3000>;
reg-names "mpu";
interrupts = <82>, <83>;
interrupt-names = "tx", "rx";
op-mode = <0>; /* MCASP_IIS_MODE */
tdm-slots = <2>;
serial-dir = <
0 0 0 0 /* 0: INACTIVE, 1: TX, 2: RX */
0 0 0 0
0 0 0 1
2 0 0 0 >;
tx-num-evt = <1>;
rx-num-evt = <1>;
};