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_w...@realsil.com.cn 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

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to