[PATCH v3 1/2] drivers/watchdog: Add optional ASPEED device tree properties

[Christopher Bostic <cbostic@linux.vnet.ibm.com>]

Describe device tree optional properties:

  * aspeed,arm-reet - ARM CPU reset on signal
  * aspeed,no-soc-reset - SOC reset on signal
  * aspeed,no-sys-reset - System reset on signal
  * aspeed,interrupt - Interrupt CPU on signal
  * aspeed,external-signal - Generate external signal (WDT1 and WDT2 only)
  * aspeed,alt-boot - Boot from alternate block on signal

Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com>
---
v3 - Invert soc and sys reset to 'no' to preserve backwards
     compatibility.  SOC and SYS reset will be set by default
     without any optional parameters set
v2 - Add 'aspeed,' prefix to all optional properties
   - Add arm-reset, soc-reset, interrupt, alt-boot properties
---
 .../devicetree/bindings/watchdog/aspeed-wdt.txt    | 24 ++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt b/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt
index c5e74d7..6f18005 100644
--- a/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt
+++ b/Documentation/devicetree/bindings/watchdog/aspeed-wdt.txt
@@ -8,9 +8,33 @@ Required properties:
  - reg: physical base address of the controller and length of memory mapped
    region
 
+Optional properties:
+   Signal behavior - Whenever a timeout occurs the watchdog can be programmed
+   to generate/not generate 6 types of signals:
+
+ - aspeed,arm-reset:	If property is present then reset ARM CPU only.
+			If not specified no ARM CPU reset is done.
+
+ - aspeed,no-soc-reset: If property is present then do not reset SOC.
+			If not specified then SOC reset is done.
+
+ - aspeed,no-sys-reset: If property is present then do not reset system.
+			Typcally used in tandem with 'aspeed-external-signal'
+			If not specified then system reset is done.
+
+ - aspeed,interrupt:	If property is present then interrupt CPU.
+			If not specified then don't interrupt CPU.
+
+ - aspeed,external-signal: If property is present then signal is sent to
+			external reset counter (only WDT1 and WDT2). If not
+			specified no external signal is sent.
+ - aspeed,alt-boot:    If property is present then boot from alternate block.
+
 Example:
 
 	wdt1: watchdog@1e785000 {
 		compatible = "aspeed,ast2400-wdt";
 		reg = <0x1e785000 0x1c>;
+		aspeed,no-sys-reset;
+		aspeed,external-signal;
 	};
-- 
1.8.2.2