Hi Mark, >> >>> On Fri, Sep 27, 2013 at 05:06:38PM +0100, Kumar Gala wrote: >>>> >>>> On Sep 17, 2013, at 2:30 PM, Suman Anna wrote: >>>> >>>>> HwSpinlock IP is present only on OMAP4 and other newer SoCs, >>>>> which are all device-tree boot only. This patch adds the >>>>> base support for parsing the DT nodes, and removes the code >>>>> dealing with the traditional platform device instantiation. >>>>> >>>>> Signed-off-by: Suman Anna <s-anna@xxxxxx> >>>>> --- >>>>> .../devicetree/bindings/hwlock/omap-hwspinlock.txt | 31 +++++++++++ >>>>> arch/arm/mach-omap2/Makefile | 3 -- >>>>> arch/arm/mach-omap2/hwspinlock.c | 60 ---------------------- >>>>> drivers/hwspinlock/omap_hwspinlock.c | 23 +++++++-- >>>>> 4 files changed, 50 insertions(+), 67 deletions(-) >>>>> create mode 100644 Documentation/devicetree/bindings/hwlock/omap-hwspinlock.txt >>>>> delete mode 100644 arch/arm/mach-omap2/hwspinlock.c >>>>> >>>>> diff --git a/Documentation/devicetree/bindings/hwlock/omap-hwspinlock.txt b/Documentation/devicetree/bindings/hwlock/omap-hwspinlock.txt >>>>> new file mode 100644 >>>>> index 0000000..235b7c5 >>>>> --- /dev/null >>>>> +++ b/Documentation/devicetree/bindings/hwlock/omap-hwspinlock.txt >>>>> @@ -0,0 +1,31 @@ >>>>> +OMAP4+ HwSpinlock Driver >>>>> +======================== >>>>> + >>>>> +Required properties: >>>>> +- compatible: Currently supports only "ti,omap4-hwspinlock" for >>>>> + OMAP44xx, OMAP54xx, AM33xx, AM43xx, DRA7xx SoCs >>> >>> "Currently supports" is not something I expect to see in a binding >>> document. That sounds like a description of the driver rather than the >>> binding. >>> >>> How similar are these hardware modules? What are the differences? >> >> The IP is almost the same, they all have the same revision id. The >> number of locks (each represented by a register) though vary from one >> SoC to another (OMAP4, OMAP5, DRA7 have same number of locks, and >> AM33xx/AM43xx have a different number). The number of locks is directly >> read by the driver from a module register. There is no separate .data >> associated with the of_device_id table, so I used a single compatible >> property for all the SoCs. > > Ok. Probeability is good, it keeps these simpler :) > > I think This can be reworded to say "should contain" rather than "currently > supports only": > > - compatible: Should contain "ti,omap4-hwspinlock" for > OMAP44xx, OMAP54xx, AM33xx, AM43xx, or DRA7xx SoCs > > That way the binding allows for a future backwards-compatible variant, and > doesn't mention the current level of support in Linux. Yes, that is the change I have made in my current working set as well. > >> >>> >>>>> +- reg: Contains the hwspinlock register address range (base >>>>> + address and length) >>> >>> Is there only one register bank for the hwlock module? >> >> The lock registers start at a certain offset (0x800) within the module >> register space, and the offsets for various registers are identical >> between all SoCs. > > What are the other registers within the module? Are they shared with other > devices, or are they simply unused by the hwspinlock driver? No, they are not shared with other devices. These are like revision register, and a SYSCONFIG register which is used by the OMAP hwmod layer. This register definition is in line with other modules on OMAP. > >> >>> >>>>> +- ti,hwmods: Name of the hwmod associated with the hwspinlock device >>>>> + >>>>> +Common hwlock properties: >>>>> +The following describes the usage of the common hwlock properties (defined in >>>>> +Documentation/devicetree/bindings/hwlock/hwlock.txt) on OMAP. >>>>> + >>>>> +- hwlock-base-id: There are currently no OMAP SoCs with multiple >>>>> + hwspinlock devices. The OMAP driver uses a default >>>>> + base id value of 0 for the locks present within the >>>>> + single hwspinlock device on all SoCs. >>> >>> >>> Driver details should not leak into bindngs... >> >> OK, will remove the info on driver details. >> >>> >>> As mentioned in the other patch, I don't think this is the way to handle >>> this. I think we need a phandle + args representation. >> >> This is an optional parameter for now and I was going to revise the >> description based on comments from Kumar Gala on this thread, but I will >> wait and adjust this based on the outcome on the first patch. > > Ok. I have removed this property altogether in my current working set. Will post the v3 of the series soon. regards Suman -- 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
