mt76: mt7603: add additional EEPROM chip ID

[PsychoGame]

Some newer MT7628 based routers (notably the TP-Link Archer C50 v4) are
shipped with a chip-id of 0x7600 in the on-flash EEPROM. Add this as a
possible valid ID.

Ref: https://bugs.openwrt.org/index.php?do=details&task_id=2781

Suggested-by: Ron Asimi ron.asimi@gmail.com
Signed-off-by: David Bauer mail@david-bauer.net

[PsychoGame]

Hello @blocktrron
I've backported this patch from master to openwrt-19.07.
This patch is neccasary for Archer C50v4 devices which carry the chip-id 0x7600.
Without this patch the firmware is not correctly initialized at boot, which results in very bad 2.4GHz performance on these devices.
I added you to this patch, as you also approved the initialen patch in the master branch.

[blocktrron]

Thanks, I've applied the patch and updated the Package in OpenWrt.

[sanitariu]

Do you have similar patch for: TP-Link Archer C20 v5 which fixes 5ghz performance and tx-power ?

[PsychoGame]

Hello @sanitariu
I don't know if that chipset suffers exactly the same problem.
Is it the same chipset? Are you able to check the chip-id in your firmware.
If the problem is exactly the same, and the chipset id is same as the one added with this patch, then this should solve your problem as well.
This patch is no certainly device specific.

[kousu]

There's one weird glitch with this patch. Two reports show the 2.4GHz radio still showing up as "Generic". The signal problems are fixed so this seems to be just cosmetic. Shouldn't this have made it show up as "MediaTek MT76x2E"?