Re: [PATCH 1/7] ata: libahci_platform: comply to PHY framework

From: Miquel Raynal <miquel.raynal@bootlin.com>
To: Hans de Goede <hdegoede@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>, Andrew Lunn <andrew@lunn.ch>,
	Jason Cooper <jason@lakedaemon.net>,
	devicetree@vger.kernel.org,
	Antoine Tenart <antoine.tenart@bootlin.com>,
	Gregory Clement <gregory.clement@bootlin.com>,
	linux-pm@vger.kernel.org,
	Maxime Chevallier <maxime.chevallier@bootlin.com>,
	Nadav Haklai <nadavh@marvell.com>,
	linux-ide@vger.kernel.org, Rob Herring <robh+dt@kernel.org>,
	Jens Axboe <axboe@kernel.dk>,
	Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
	linux-arm-kernel@lists.infradead.org,
	Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Subject: Re: [PATCH 1/7] ata: libahci_platform: comply to PHY framework
Date: Fri, 30 Nov 2018 16:40:16 +0100	[thread overview]
Message-ID: <20181130164016.7699efb3@xps13> (raw)
In-Reply-To: <f14c6e8e-73a9-0b62-0dbc-87d390789c0c@redhat.com>

Hi Hans,

Thanks for the review.

Hans de Goede <hdegoede@redhat.com> wrote on Fri, 23 Nov 2018 11:33:15
+0100:

> Hi Miquel,
> 
> On 23-11-18 11:15, Miquel Raynal wrote:
> > Current implementation of the libahci does not take into account the
> > new PHY framework. Correct the situation by adding a call to
> > phy_set_mode() before phy_power_on() and by adding calls to
> > ahci_platform_enable/disable_phys() at suspend/resume_host() time.
> > 
> > Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> > ---
> >   drivers/ata/libahci_platform.c | 11 +++++++++++
> >   1 file changed, 11 insertions(+)
> > 
> > diff --git a/drivers/ata/libahci_platform.c b/drivers/ata/libahci_platform.c
> > index 4b900fc659f7..9f33f72b674b 100644
> > --- a/drivers/ata/libahci_platform.c
> > +++ b/drivers/ata/libahci_platform.c
> > @@ -56,6 +56,12 @@ static int ahci_platform_enable_phys(struct ahci_host_priv *hpriv)
> >   		if (rc)
> >   			goto disable_phys;  
> >   > +		rc = phy_set_mode(hpriv->phys[i], PHY_MODE_SATA);  
> > +		if (rc) {
> > +			phy_exit(hpriv->phys[i]);
> > +			goto disable_phys;
> > +		}
> > +  
> 
> I see that phy_set_mode returns 0 for drivers which do not implement it,
> so this should be fine.
> 
> 
> >   		rc = phy_power_on(hpriv->phys[i]);
> >   		if (rc) {
> >   			phy_exit(hpriv->phys[i]);
> > @@ -738,6 +744,8 @@ int ahci_platform_suspend_host(struct device *dev)
> >   	writel(ctl, mmio + HOST_CTL);
> >   	readl(mmio + HOST_CTL); /* flush */  
> >   > +	ahci_platform_disable_phys(hpriv);  
> > +
> >   	return ata_host_suspend(host, PMSG_SUSPEND);
> >   }
> >   EXPORT_SYMBOL_GPL(ahci_platform_suspend_host);  
> 
> I'm afraid that this and the matching change in ahci_platform_suspend_host
> needs to be guarded by a flag, there are quite a few sata drivers
> using the libahci_platform functions as well as quite a few sata drivers
> combining this with using phy drivers.
> 
> I'm worried that doing this unconditionally on drivers which have
> not been tested with this change my break things.
> 
> I think it might be cleanest to extend the existing flags passed
> to ahci_platform_get_resources with a flag for this and storing them
> somewhere in ahci_host_priv so that the suspend/resume functions can
> get to them.

I understand your concern, please have a look at the v2 which addresses
this the way you suggested.

Thanks,
Miquèl

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