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    SubjectRe: [PATCH] wireless-2.6 zd1211rw check against regulatory domain rather than hardcoded value of 11
    Date
    On Monday 30 October 2006 23:59, Uli Kunitz wrote:
    > Johannes Berg wrote:
    > >> I'm not so sure about this. This patching might be US-specific and we
    > >> cannot simply apply the setting for top channel of another domain
    > >> instead of channel 11. One option would be to set the value only under
    > >> the US regulatory domain.
    > >
    > > ??
    > > What the patch does is replace the top channel which is hardcoded to 11
    > > by the top channel given by the current regulatory domain. How can that
    > > be wrong? Except that you may want to init the regulatory domain from
    > > the EEPROM but I'm not sure how the ieee80211 code works wrt. that.
    > >
    > > johannes
    >
    > The problem is not so much that I don't trust the geo code, but whether
    > setting the register to that band-edge value for a higher channel is
    > the right thing to do. It looks like that this is a hack for FFC
    > compliance. Therefore I suggest to patch CR128 only
    > for the US regulatory domain.
    >
    > Here is the code from the GPL vendor driver (zdhw.c):
    >
    > if (pObj->HWFeature & BIT_21) //6321 for FCC regulation, enabled HWFeature 6M band edge bit (for AL2230, AL2230S)
    > {
    > if (ChannelNo == 1 || ChannelNo == 11) //MARK_003, band edge, these may depend on PCB layout
    > {
    > pObj->SetReg(reg, ZD_CR128, 0x12);
    > pObj->SetReg(reg, ZD_CR129, 0x12);
    > pObj->SetReg(reg, ZD_CR130, 0x10);
    > pObj->SetReg(reg, ZD_CR47, 0x1E);
    > }
    > else //(ChannelNo 2 ~ 10, 12 ~ 14)
    > {
    > pObj->SetReg(reg, ZD_CR128, 0x14);
    > pObj->SetReg(reg, ZD_CR129, 0x12);
    > pObj->SetReg(reg, ZD_CR130, 0x10);
    > pObj->SetReg(reg, ZD_CR47, 0x1E);
    > }
    > }
    >
    > The patch from Holden would set ZD_CR128 to 0x12 for the highest channel,
    > which would not reflect the logic of the vendor driver.

    I think the real question is: What does this "band edge" bit actually do?
    Did you notice any difference when setting it? Does TX power in/decrease?
    Did you see differences in the physical range (max distance from the AP
    for which you're still able to connect).
    I don't know what channel 1 and 11 have in common. Why don't we set the
    bit for channel 14? Isn't that an "edge", too?

    --
    Greetings Michael.
    -
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