On Mon, Mar 25, 2013 at 02:23:45PM +0800, wwang wrote:
> 于 2013年03月25日 14:00, Dan Carpenter 写道:
> >On Mon, Mar 25, 2013 at 10:13:56AM +0800, wei_wang@xxxxxxxxxxxxxx wrote:
> >>+static int rts5249_optimize_phy(struct rtsx_pcr *pcr)
> >>+{
> >>+ int err;
> >>+
> >>+ err = rtsx_pci_write_phy_register(pcr, 0x19, 0xFE46);
> >>+ if (err < 0)
> >>+ return err;
> >>+
> >>+ mdelay(1);
> >Why do we have the mdelay() and the later msleep(5)?
> >rtsx_pci_write_phy_register() busy loops until the write succeeds or
> >it returns -ETIMEOUT. The extra wait here seems unnecessary.
> >
> >regards,
> >dan carpenter
> >
> >
> >.
>
> Hi,
>
> The busy loops in rtsx_pci_write_phy_register only tell us that the
> write sequence succeeds. The device still needs to wait for a while
> until the internal signal stable. Or else the timing won't fit the
> requirement.
> All of the delays in the driver are necessary.
Ok. Cool.
regards,
dan carpenter
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