On 2018-10-30 21:02, Rob Herring wrote:
On Tue, Oct 30, 2018 at 3:41 AM <bperumal@xxxxxxxxxxxxxx> wrote:
On 2018-10-16 00:54, Rob Herring wrote:
> On Thu, Oct 04, 2018 at 05:12:43PM +0530, Bhagavathi Perumal S wrote:
>> This adds new dt entry ext-fem-name, it is used by ath10k driver
>> to select correct timing parameters and configure it in target wifi
>> hardware.
>> The Front End Module(FEM) normally includes tx power amplifier(PA) and
>> rx low noise amplifier(LNA). The default timing parameters like tx end
>> to
>> PA off timing values were fine tuned for internal FEM used in
>> reference
>> design. And these timing values can not be same if ODM modifies
>> hardware
>> design with different external FEM. This DT entry helps to choose
>> correct
>> timing values in driver if different external FEM hardware used.
>
> 'dt-bindings: net: ath10k: ...' for the subject please.
Sure, I will change and send v2 patch.
>
>>
>> Signed-off-by: Bhagavathi Perumal S <bperumal@xxxxxxxxxxxxxx>
>> ---
>> .../bindings/net/wireless/qcom,ath10k.txt | 22
>> ++++++++++++++++++++++
>> 1 file changed, 22 insertions(+)
>>
>> diff --git
>> a/Documentation/devicetree/bindings/net/wireless/qcom,ath10k.txt
>> b/Documentation/devicetree/bindings/net/wireless/qcom,ath10k.txt
>> index 7fd4e8c..fbaf309 100644
>> --- a/Documentation/devicetree/bindings/net/wireless/qcom,ath10k.txt
>> +++ b/Documentation/devicetree/bindings/net/wireless/qcom,ath10k.txt
>> @@ -56,6 +56,7 @@ Optional properties:
>> the length can vary between hw versions.
>> - <supply-name>-supply: handle to the regulator device tree node
>> optional "supply-name" is "vdd-0.8-cx-mx".
>> +- ext-fem-name: name of external front end module used.
>
> What are valid names? What if the OS doesn't recognize the name?
> Perhaps
Some valid FEM devices are "microsemi-lx5586", "sky85703-11" and
"sky85803" etc.
Currently driver accepts only "microsemi-lx5586", Since this FEM
requires different timing settings,
Assuming you keep this, then you need to enumerate what are valid
values in the binding. Otherwise, 'ext-fem-name = "rob"' is valid.
Sure, Will enumerate valid values in v2 patch.
And it can be extended for other FEM devices in future.
If OS doesn't recognize the name, it uses predefined default timing
settings.
> this should be a compatible string for the particular module instead?
> Then it could cover any differences, not just the FEM.
>
No, it is specific to FEM device.
You will be better off having either a specific compatible string or
using VID/PID as this is a PCI device. Then you can handle other
differences you may find between h/w versions without a DT change.
FEM is a part of wifi device, and not a separate PCI device. Different
external
FEM can be used in a same wifi device, so it might not be feasible to
define
a compatible string to cover any other differences. IMO we can go with
the property name instead of defining compatible string specific to
every FEM device.
>>
>> Example (to supply the calibration data alone):
>>
>> @@ -150,3 +151,24 @@ wifi@18000000 {
>> <0 141 0 /* CE11 */ >;
>> vdd-0.8-cx-mx-supply = <&pm8998_l5>;
>> };
>> +
>> +Example (to supply the external front end module name):
>> +
>> +In this example, the front end module is defined as a property of the
>> ath10k
>> +device node.
>
> Really need a whole new example for 1 property?
Will add this property in existing example.
>
>> +
>> +pci {
>> + pcie@0 {
>> + reg = <0 0 0 0 0>;
>> + #interrupt-cells = <1>;
>> + #size-cells = <2>;
>> + #address-cells = <3>;
>> + device_type = "pci";
>> +
>> + ath10k@0,0 {
>
> wifi@0,0
Added in ath10k@0,0 to make consistent with existing property
"qcom,ath10k-calibration-data" below,
"
I don't see how that matters.
pci {
pcie@0 {
reg = <0 0 0 0 0>;
#interrupt-cells = <1>;
#size-cells = <2>;
#address-cells = <3>;
device_type = "pci";
ath10k@0,0 {
reg = <0 0 0 0 0>;
device_type = "pci";
qcom,ath10k-calibration-data = [ 01 02 03 ...
];
};
};
};
"
If wifi@0,0 is preferable, then I will add new entry "wifi@0,0" and
add
ext-fem-name into it.
Node names are supposed to reflect the class of device, not the model.
See the DT spec for a list.
Will change accordingly.
>
>> + reg = <0 0 0 0 0>;
>> + device_type = "pci";
Also, this is wrong. Only PCI bridges should have this property. dtc
will give you a warning on this.
Will remove it in v2 patch.
>> + ext-fem-name = "microsemi-lx5586";
>> + };
>> + };
>> +};
>> --
>> 1.9.1
>>
Thanks, Sorry for the delayed response,
Bhagavathi Perumal S.
