Date: Mon, 25 Mar 2013 09:29:00 +0300
From: Dan Carpenter <dan.carpenter@oracle.com>
To: wwang <wei_wang@realsil.com.cn>
Cc: cjb@laptop.org, sameo@linux.intel.com, gregkh@linuxfoundation.org,
        linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org,
        rogerable@realtek.com, devel@linuxdriverproject.org
Subject: Re: [PATCH] mfd:rtsx: Support RTS5249
Message-ID: <20130325062900.GC9189@mwanda>
References: <1364177636-4294-1-git-send-email-wei_wang@realsil.com.cn>
 <20130325060038.GD9138@mwanda>
 <514FED71.8020307@realsil.com.cn>
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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@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

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