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    SubjectRe: [PATCHv2 2/2] PCAP regulator driver (for 2.6.32)
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    Em Sáb, 2009-06-27 às 02:04 +0100, Mark Brown escreveu:
    > > + if (vreg->n_voltages == 1)
    > > + return -EINVAL;
    >
    > It'd be a little more friendly to check if the supported voltage is in
    > the requested range. However, that'd only be an issue if constraints
    > allowed voltage changes which is obviously broken so a comment to that
    > effect would be enough. I wouldn't have mentioned it but...

    Ok, I will add a comment.

    > > + ezx_pcap_read(pcap, vreg->reg, &tmp);
    > > + tmp |= (1 << vreg->en);
    > > + ezx_pcap_write(pcap, vreg->reg, tmp);
    >
    > This read/modify/write cycle is racy; the individual regulator is locked
    > by the core but this register is shared between all regulators on the
    > chip so if two are being updated at once things will go wrong. Most of
    > the MFDs have a set_bits() function that does an atomic read/modify/write
    > cycle for cases like this.

    Good point, thanks! :)

    --
    Daniel Ribeiro
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