On 03/17/2016 10:01 AM, Rob Herring wrote:
> On Mon, Mar 07, 2016 at 01:51:57PM -0600, Franklin S Cooper Jr wrote:
>> Since the PWMSS and its subdevices (eCAP and ePWM) use the same address
>> space then the range property should be empty. Update the documentation
>> to show the correct usage.
> Why does it matter? An empty ranges is generally not preferred.
Someone pointed out that ranges should probably be empty. I
double checked it with what is in the ePAPR doc and based on
the definition it should be set to empty. I also checked
against the am33xx.dtsi and saw that both USB and ethernet
uses an empty value for ranges.
Can you elaborate on why this isn't preferable?
>
>> Signed-off-by: Franklin S Cooper Jr <fcoo...@ti.com>
>> ---
>> Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt | 12 ++++--------
>> 1 file changed, 4 insertions(+), 8 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt
>> b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt
>> index f7eae77..672fa71 100644
>> --- a/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt
>> +++ b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt
>> @@ -7,11 +7,9 @@ Required properties:
>> Should set to 1.
>> - size-cells: specify number of u32 entries needed to specify child nodes
>> size
>> in reg property. Should set to 1.
>> -- ranges: describes the address mapping of a memory-mapped bus. Should set
>> to
>> - physical address map of child's base address, physical address within
>> - parent's address space and length of the address map. For am33xx,
>> - 3 set of child register maps present, ECAP register space, EQEP
>> - register space, EHRPWM register space.
>> +- ranges: describes the address mapping of a memory-mapped bus. Its value
>> + should be empty since no address translation is needed between the
>> + parent and the child.
>>
>> Also child nodes should also populated under PWMSS DT node.
>>
>> @@ -23,9 +21,7 @@ pwmss0: pwmss@48300000 {
>> #address-cells = <1>;
>> #size-cells = <1>;
>> status = "disabled";
>> - ranges = <0x48300100 0x48300100 0x80 /* ECAP */
>> - 0x48300180 0x48300180 0x80 /* EQEP */
>> - 0x48300200 0x48300200 0x80>; /* EHRPWM */
>> + ranges;
>>
>> /* child nodes go here */
>> };
>> --
>> 2.7.0
>>
