ZTE MC315 CDMA wireless PCMCIA data card on Linux

[Prof. Prabhat Ranjan]

I have been trying to get a ZTE MC315 wireless PCMCIA data card working on 
Linux. The technical details are given at the following link:

http://www.ecplaza.net/tradeleads/seller/3538126/cdma20001x_wireless_data_card_mc315_series.html

If one inserts this card, it gets recognized and attached to ttyS3 port as 
shown in the kernel message below:
===========
Nov  1 14:25:55 localhost kernel: pccard: PCMCIA card inserted into slot 0
Nov  1 14:25:55 localhost kernel: pcmcia: registering new device pcmcia0.0
Nov  1 14:25:56 localhost kernel: ttyS3: detected caps 00000700 should be 
00000100
Nov  1 14:25:56 localhost kernel: 0.0: ttyS3 at I/O 0x2e8 (irq = 3) is a 
16C950/954
===========

However, after this it does not respond to any AT commands etc. I have tried 
this on Fedora Core 5 with Kernel 2.6.17 /2.6.18 and both show the same 
behaviour. (I must add that card is working in windows). This behaviour has 
been reported on the net also for this card so it is not an isolated case.


Basically it is based on Qualcomm 5105/6025 platform and seems to use Oxford 
Semiconductors OXCF950 Rev B. Here are the output from pccardctl :

$MANFID - 0279,950b
$FUNCID - 2
$PRODID_1 - CDMA1X
$PRODID_2 - CARD

In the file  "linux-2.6.18.1/drivers/serial/serial_cs.c" a number of 
workaround for OXCF950 Rev B have been added. In addition, I have also noted 
that in file 8250.c, 8250_pci.c and sunsu.c workarounds for this paricular 
chip. One of this seems to be related to Baudrate miscalculation. However, 
this workaround has not been done in serial_cs.c.

I am wondering whether the card is not responding due to one of these 
workarounds not being applied in serial_cs.c or any other pointers one may 
have.


Thanks,
- Prabhat Ranjan