[PATCH 1/2] Documentation: DT: Add entry for ARM SP805-WDT

Bhupesh SHARMA
2015-11-18T14:03:15Z

Hi Rob,

Thanks for the review.

On Tue, Nov 17, 2015 at 5:44 AM, Rob Herring <robh@kernel.org> wrote:
> On Mon, Nov 16, 2015 at 02:45:25PM +0000, Mark Rutland wrote:
>> On Mon, Nov 16, 2015 at 07:54:42PM +0530, Bhupesh Sharma wrote:
>> > This patch adds a devicetree binding documentation for ARM's
>> > SP805 WatchDog Timer.
>> >
>> > Signed-off-by: Bhupesh Sharma <bhupesh.sharma@freescale.com>
>> > ---
>> > .../devicetree/bindings/watchdog/sp805-wdt.txt | 33 ++++++++++++++++++++
>> > 1 file changed, 33 insertions(+)
>> > create mode 100644 Documentation/devicetree/bindings/watchdog/sp805-wdt.txt
>> >
>> > diff --git a/Documentation/devicetree/bindings/watchdog/sp805-wdt.txt b/Documentation/devicetree/bindings/watchdog/sp805-wdt.txt
>> > new file mode 100644
>> > index 0000000..ec70fe9
>> > --- /dev/null
>> > +++ b/Documentation/devicetree/bindings/watchdog/sp805-wdt.txt
>> > @@ -0,0 +1,33 @@
>> > +* ARM SP805 Watchdog Timer (WDT) Controller
>> > +
>> > +SP805 WDT is a ARM Primecell Peripheral and has a standard-id register that
>> > +can be used to identify the peripheral type, vendor, and revision.
>> > +This value can be used for driver matching.
>> > +

[snip..]

>> > +As SP805 WDT is a primecell IP, it follows the base bindings specified in
>> > +'arm/primecell.txt'
>> > +
>> > +Required properties:
>> > +- compatible : Should be "arm,sp805-wdt", "arm,primecell"
>> > +- reg : Base address and size of the watchdog timer registers.
>> > +- interrupts : Should specify WDT interrupt number.
>> > +
>> > +Optional properties:
>> > +- clocks : From common clock binding. First clock is phandle to clock for apb
>> > + pclk. Additional clocks are optional.
>> > +- clock-names : From common clock binding. Shall be "apb_pclk" for first clock.
>>
>> The hardware has "WDOGCLK", which is what the driver appears to expect
>> first implicitly.
>
> The h/w has 2 clocks, PCLK and WDOGCLK, so both should be described and
> neither should be optional.

As per the SP805 WDT TRM I have with me (see [1], Figure 1-1), this
h/w has only only input
clock WDOGCLK.

[1] http://infocenter.arm.com/help/topic/com.arm.doc.ddi0270b/DDI0270.pdf

Regards,
Bhupesh

> Rob
>