Re: [PATCH] mfd:rtsx: Support RTS5249

[wwang]

ä 2013å03æ25æ 14:00, Dan Carpenter åé:
> 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.

BR,
Wei
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