Re: [PATCH] ide: fix drive side 80c cable check, take 2

[Sergei Shtylyov <sshtylyov@ru.mvista.com>]

Hello, I wrote:

>> eighty_ninty_three() had word 93 validitity check but not the 80c bit
>> test itself (bit 12).  This increases the chance of incorrect wire
>> detection especially because host side cable detection is often
>> unreliable and we sometimes soley depend on drive side cable
>> detection.  Fix it.

>> Signed-off-by: Tejun Heo <htejun@gmail.com>

>> diff --git a/drivers/ide/ide-iops.c b/drivers/ide/ide-iops.c
>> index badde63..6558055 100644
>> --- a/drivers/ide/ide-iops.c
>> +++ b/drivers/ide/ide-iops.c
>> @@ -607,6 +607,8 @@ u8 eighty_ninty_three (ide_drive_t *drive)
>>      if(!(drive->id->hw_config & 0x4000))
>>          return 0;
>>  #endif /* CONFIG_IDEDMA_IVB */
>> +    if (!(drive->id->hw_config & 0x2000))
>> +        return 0;

>    Haha, you know just *why* this was wrong? Bit 13 of the word 93 when 
> *set* means 40c cable, not 80c!  Look at the table 9 in ATA/PI-6, for 
> example, and then into the bit description in the table 27.

    Oops, that's a host side detection, the device side CBLID- seems to have 
the opposite levels. Should have really be looking at the table 8. :-<

>>      return 1;
>>  }

    Actually, trying to find out why 'hdparm -i' clips the modes to udma2 
sometimes...

MBR, Sergei