Support for LTE bands > 64

[Reinhard Speyerer]

On Thu, Nov 09, 2017 at 04:10:06PM +0100, Carlo Lobrano wrote:
> Hey Aleksander,
> 
> On 9 November 2017 at 15:56, Dan Williams <dcbw at redhat.com> wrote:
> 
> > On Thu, 2017-11-09 at 08:32 +0100, Aleksander Morgado wrote:
> > > Hey,
> > >
> > > Most TLVs in the QMI protocol used a 64bit mask to flag the list of
> > > LTE bands, and therefore there was no way to reference bands greater
> > > than 64. These patches include support for additional TLVs that allow
> > > managing those bands.
> > >
> > > In particular, these patches include support for managing band 66 in
> > > QMI devices that support it, like the Telit LM940.
> > >
> > >   [PATCH 1/3] nas: define additional LTE bands
> > >   [PATCH 2/3] dms: new 'Extended LTE Band Capability' TLV in "Get
> > > Band...
> > >   [PATCH 3/3] nas: new 'Extended LTE Band Preference' TLV in
> > > "Set/Get...
> > >
> > > Comments?
> 
> 
> ???I tested the patch on a LM940 and looks good to me as well. Only two
> observation:
> 
> 1. LM940 with *nas-get-system-selection-preference* returns an unexpected
> pair of bands 252 and 255. Not sure if it is a modem error or some kind of
> valid information, do you have any idea?
> 
> <<<<<< TLV:
> <<<<<<   type       = "Extended LTE Band Preference" (0x23)
> <<<<<<   length     = 32
> <<<<<<   value      =
> DF:18:09:3B:A0:01:00:00:02:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:48
> <<<<<<   translated = [ mask_low = '1787696847071' mask_mid_low = '2'
> mask_mid_high = '0' mask_high = '5188146770730811392' ]
> 
> [/dev/cdc-wdm1] Successfully got system selection preference
>     Emergency mode: 'no'
>     Mode preference: 'umts'
>     Band preference: 'wcdma-2100, wcdma-pcs-1900, wcdma-1700-us,
> wcdma-850-us, wcdma-900'
>     LTE band preference: '1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 20, 25, 26, 28,
> 29, 30, 38, 40, 41'
>     LTE band preference (extended): '1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 20,
> 25, 26, 28, 29, 30, 38, 40, 41, 66, 252, 255'
>     TD-SCDMA band preference: 'a, b, c, d, e, f'
>     Roaming preference: 'any'
>     Network selection preference: 'automatic'
>     Service domain preference: 'cs-ps'
>     Service selection preference: 'automatic'

Hi Carlo,

LTE bands 252 and 255 are used for supplemental downlink carriers in
the unlicensed 5 GHz band. If the LM940 supports LTE-U (didn't see it
mentioned in the data sheet) both values would be valid band values.

In addition to the Extended LTE Band Preference support Get LTE Cphy
CA Info might also have to be extended for the LM940 to return
additional SCell information for 3CA.

Regards,
Reinhard