kernel NULL pointer dereference in samcop_sdi.c

Hello,

I've been playing with the 2.6 kernel lately and I'm experiencing the 
following problem which I can't solve. I compile everything into the kernel 
(no modules). When booting I always get:

Unable to handle kernel NULL pointer dereference at virtual address 00000000    
pgd = c0004000                                                                  
[00000000] *pgd=00000000                                                        
Internal error: Oops: f5 [#1]                                                   
Modules linked in:                                                              
CPU: 0                                                                          
PC is at samcop_sdi_probe+0xb0/0x244                                            
LR is at setup_irq+0x124/0x148                                                  
pc : [<c0124788>]    lr : [<c001d4c0>]    Not tainted                           
sp : c02c5f2c  ip : c02c5ee0  fp : c02c5f54                                     
r10: 00000000  r9 : 00000000  r8 : 00000000                                     
r7 : c02fb208  r6 : c03a73a0  r5 : c03a742c  r4 : 00000000
r3 : 00000000  r2 : c02c4000  r1 : 00000003  r0 : 00000000                      
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  Segment kernel                      
Control: 397F  Table: A0004000  DAC: 00000017                                   
Process swapper (pid: 1, stack limit = 0xc02c4194)                              
Stack: (0xc02c5f2c to 0xc02c6000)                                               
5f20:                            c03a742c c02fb208 00000000 c01bd748 c01bd748   
5f40: 00000000 00000000 c02c5f70 c02c5f58 c0102b60 c01246e4 c02fb2b0 c02c5f88   
5f60: c0102c58 c02c5f84 c02c5f74 c0102ca4 c0102b10 00000000 c02c5fb0 c02c5f88   
5f80: c0102448 c0102c64 c01bc31c c01bc31c c02fb248 c01bd75c c01bd748 00000001   
5fa0: c01bc234 c02c5fd8 c02c5fb4 c0102720 c0102404 c02c4000 c0019744 00000001   
5fc0: 00000000 00000000 00000000 c02c5ff4 c02c5fdc c001b0e4 c01026c0 00000000   
5fe0: 00000000 00000000 00000000 c02c5ff8 c0038688 c001b06c c00e5b14 c00e5b28   
Backtrace:                                                                      
[<c01246d8>] (samcop_sdi_probe+0x0/0x244) from [<c0102b60>] 
(driver_probe_device
+0x5c/0xa8)
[<c0102b04>] (driver_probe_device+0x0/0xa8) from [<c0102ca4>] 
(__driver_attach+0
x4c/0x78)                                                                       
 r6 = C0102C58  r5 = C02C5F88  r4 = C02FB2B0                                    
[<c0102c58>] (__driver_attach+0x0/0x78) from [<c0102448>] 
(bus_for_each_dev+0x50
/0x8c)                                                                          
 r4 = 00000000                                                                  
[<c01023f8>] (bus_for_each_dev+0x0/0x8c) from [<c0102720>] 
(bus_add_driver+0x6c/
0x114)                                                                          
 r7 = C01BC234  r6 = 00000001  r5 = C01BD748  r4 = C01BD75C                     
[<c01026b4>] (bus_add_driver+0x0/0x114) from [<c001b0e4>] (init+0x84/0x1cc)     
[<c001b060>] (init+0x0/0x1cc) from [<c0038688>] (do_exit+0x0/0xba4)             
 r6 = 00000000  r5 = 00000000  r4 = 00000000                                    
Code: e3e04001 ea000054 e5953010 e3a01003 (e5930000)                            
 <0>Kernel panic - not syncing: Attempted to kill init!

I've found the problem is that in samcop_sdi.c in function samcop_sdi_probe(), 
there is plat variable which gets value from dev->platform_data. The problem 
is this value is NULL and it's not verified anywhere. Later on, it's 
dereferenced which takes the kernel down.

I can't continue in looking further because I don't know where the 
platform_data var is being filled in. Can you please give me some hints or 
take a look at it yourselves?

Thanks...
Radek Podgorny

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