On Wed, Nov 18, 2015 at 8:03 AM, Bhupesh SHARMA <bhupesh.linux@xxxxxxxxx> wrote: > Hi Rob, > > Thanks for the review. > > On Tue, Nov 17, 2015 at 5:44 AM, Rob Herring <robh@xxxxxxxxxx> 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@xxxxxxxxxxxxx> >>> > --- >>> > .../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 Look closer, PCLK is in the AMBA bus signals. The version online has some timing diagrams also which I didn't find here. Rob -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
