Add documentation for the DMA properties required when using the
PWM controller of the bcm2835 for analog audio output.
Signed-off-by: Michael Zoran <mzoran@xxxxxxxxxxxx>
---
Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt b/Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt
index cf573e85b11d..08fc06fc083a 100644
--- a/Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt
+++ b/Documentation/devicetree/bindings/pwm/pwm-bcm2835.txt
@@ -1,14 +1,21 @@
BCM2835 PWM controller (Raspberry Pi controller)
Required properties:
-- compatible: should be "brcm,bcm2835-pwm"
+- compatible: should be "brcm,bcm2835-pwm" or "brcm,bcm2835-analog-audio"
- reg: physical base address and length of the controller's registers
- clocks: This clock defines the base clock frequency of the PWM hardware
system, the period and the duty_cycle of the PWM signal is a multiple of
the base period.
+
+Required properties(PWM Output):
- #pwm-cells: Should be 2. See pwm.txt in this directory for a description of
the cells format.
+Required properties(Audio Output):
+- dmas: Should contain one entry pointing to the DMA channel used to
+ transfer audio data
+- dma-names: Should contain "tx"
+
Examples:
pwm@2020c000 {
--
2.11.0
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