EM7565 / carrier aggregation info

[Bjørn Mork]

Sebastian Sjoholm <sebastian.sjoholm at gmail.com> writes:

BTW, this was noted before.  But just to document that it is a firmware
bug and not a problem in libqmi. Compare these two TLVs from the LM940:

> <<<<<< TLV:
> <<<<<<   type       = "Phy CA Agg SCell Info" (0x12)
> <<<<<<   length     = 14
> <<<<<<   value      = 04:00:86:0B:05:00:00:00:7E:00:02:00:00:00
> <<<<<<   translated = [ physical_cell_id = '4' rx_channel = '2950' dl_bandwidth = '20' lte_band = 'eutran-7' state = 'activated' ]
> <<<<<< TLV:
> <<<<<<   type       = "Phy CA Agg PCell Info" (0x13)
> <<<<<<   length     = 10
> <<<<<<   value      = 05:00:4C:0C:05:00:00:00:7E:00
> <<<<<<   translated = [ physical_cell_id = '5' rx_channel = '3148' dl_bandwidth = '20' lte_band = 'eutran-7' ]

and the EM7565:

> <<<<<< TLV:
> <<<<<<   type       = "Phy CA Agg SCell Info" (0x12)
> <<<<<<   length     = 14
> <<<<<<   value      = 04:00:86:0B:05:00:00:00:7F:00:02:00:00:00
> <<<<<<   translated = [ physical_cell_id = '4' rx_channel = '2950' dl_bandwidth = '20' lte_band = 'eutran-8' state = 'activated' ]
> <<<<<< TLV:
> <<<<<<   type       = "Phy CA Agg PCell Info" (0x13)
> <<<<<<   length     = 10
> <<<<<<   value      = 05:00:4C:0C:05:00:00:00:7F:00
> <<<<<<   translated = [ physical_cell_id = '5' rx_channel = '3148' dl_bandwidth = '20' lte_band = 'eutran-8' ]


These should obviously be identical.  But they are not. The band index
is off by one in the EM7565 output.  And as you can see from the raw
value: It *is* actually off by one (0x007F instead of 0x007E).  Weird.
I hope they are going to fix that.  We can always fix it up here since
we also get the channel number, but it is so messy I don't think it is
worth it.  If Qualcomm can't be bothered to get something like this
correct, then I don't think it is our job to paint over it.


Bjørn