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Message-ID: <338419fd10ffcc62b135d924f766d66af8186346.camel@pengutronix.de>
Subject: Re: [PATCH v3 14/18] phy: cadence-torrent: add suspend and resume
 support
From: Philipp Zabel <p.zabel@pengutronix.de>
To: Thomas Richard <thomas.richard@bootlin.com>, Linus Walleij
 <linus.walleij@linaro.org>, Bartosz Golaszewski <brgl@bgdev.pl>, Andy
 Shevchenko <andy@kernel.org>, Tony Lindgren <tony@atomide.com>, Haojian
 Zhuang <haojian.zhuang@linaro.org>,  Vignesh R <vigneshr@ti.com>, Aaro
 Koskinen <aaro.koskinen@iki.fi>, Janusz Krzysztofik <jmkrzyszt@gmail.com>,
 Andi Shyti <andi.shyti@kernel.org>, Peter Rosin <peda@axentia.se>, Vinod
 Koul <vkoul@kernel.org>, Kishon Vijay Abraham I <kishon@kernel.org>,
 Lorenzo Pieralisi <lpieralisi@kernel.org>, Krzysztof
 =?UTF-8?Q?Wilczy=C5=84ski?= <kw@linux.com>, Rob Herring <robh@kernel.org>,
 Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, 
 linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org, 
 linux-i2c@vger.kernel.org, linux-phy@lists.infradead.org, 
 linux-pci@vger.kernel.org, gregory.clement@bootlin.com,
 theo.lebrun@bootlin.com,  thomas.petazzoni@bootlin.com, u-kumar1@ti.com
Date: Wed, 21 Feb 2024 14:58:43 +0100
In-Reply-To: <113b7f2e-1313-4ebf-a403-e5fcae8f01ca@bootlin.com>
References: <20240102-j7200-pcie-s2r-v3-0-5c2e4a3fac1f@bootlin.com>
	 <20240102-j7200-pcie-s2r-v3-14-5c2e4a3fac1f@bootlin.com>
	 <c105bfa8567f9e76731f2b018f4ca3176357204d.camel@pengutronix.de>
	 <113b7f2e-1313-4ebf-a403-e5fcae8f01ca@bootlin.com>
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On Mi, 2024-02-21 at 14:41 +0100, Thomas Richard wrote:
> On 2/21/24 14:09, Philipp Zabel wrote:
> > On Do, 2024-02-15 at 16:17 +0100, Thomas Richard wrote:
> > > Add suspend and resume support.
> > >=20
> > > The already_configured flag is cleared during the suspend stage to fo=
rce
> > > the PHY initialization during the resume stage.
> > >=20
> > > Based on the work of Th=C3=A9o Lebrun <theo.lebrun@bootlin.com>
> > >=20
> > > Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
> > > ---
> > >  drivers/phy/cadence/phy-cadence-torrent.c | 54 +++++++++++++++++++++=
++++++++++
> > >  1 file changed, 54 insertions(+)
> > >=20
> > > diff --git a/drivers/phy/cadence/phy-cadence-torrent.c b/drivers/phy/=
cadence/phy-cadence-torrent.c
> > > index 52cadca4c07b..f8945a11e7ca 100644
> > > --- a/drivers/phy/cadence/phy-cadence-torrent.c
> > > +++ b/drivers/phy/cadence/phy-cadence-torrent.c
> > > @@ -3005,6 +3005,59 @@ static void cdns_torrent_phy_remove(struct pla=
tform_device *pdev)
> > >  	cdns_torrent_clk_cleanup(cdns_phy);
> > >  }
> > > =20
> > > +static int cdns_torrent_phy_suspend_noirq(struct device *dev)
> > > +{
> > > +	struct cdns_torrent_phy *cdns_phy =3D dev_get_drvdata(dev);
> > > +	int i;
> > > +
> > > +	reset_control_assert(cdns_phy->phy_rst);
> > > +	reset_control_assert(cdns_phy->apb_rst);
> > > +	for (i =3D 0; i < cdns_phy->nsubnodes; i++)
> > > +		reset_control_assert(cdns_phy->phys[i].lnk_rst);
> > > +
> > > +	if (cdns_phy->already_configured)
> > > +		cdns_phy->already_configured =3D 0;
> > > +	else
> > > +		clk_disable_unprepare(cdns_phy->clk);
> > > +
> > > +	return 0;
> > > +}
> > > +
> > > +static int cdns_torrent_phy_resume_noirq(struct device *dev)
> > > +{
> > > +	struct cdns_torrent_phy *cdns_phy =3D dev_get_drvdata(dev);
> > > +	int node =3D cdns_phy->nsubnodes;
> > > +	int ret, i;
> > > +
> > > +	ret =3D cdns_torrent_clk(cdns_phy);
> > > +	if (ret)
> > > +		goto clk_cleanup;
> > > +
> > > +	/* Enable APB */
> > > +	reset_control_deassert(cdns_phy->apb_rst);
> > > +
> > > +	if (cdns_phy->nsubnodes > 1) {
> > > +		ret =3D cdns_torrent_phy_configure_multilink(cdns_phy);
> > > +		if (ret)
> > > +			goto put_lnk_rst;
> > > +	}
> > > +
> > > +	return 0;
> > > +
> > > +put_lnk_rst:
> > > +	for (i =3D 0; i < node; i++)
> > > +		reset_control_assert(cdns_phy->phys[i].lnk_rst);
> >=20
> > The same cleanup is found in probe. Would it be cleaner to move this
> > into cdns_torrent_phy_configure_multilink() instead of duplicating it
> > here?
>=20
> Hello Philipp,
>=20
> Yes I could, but from my point of view, it would not be cleaner.
> This cleanup is called from many places in the probe:
> -
> https://elixir.bootlin.com/linux/v6.8-rc5/source/drivers/phy/cadence/phy-=
cadence-torrent.c#L2948
> -
> https://elixir.bootlin.com/linux/v6.8-rc5/source/drivers/phy/cadence/phy-=
cadence-torrent.c#L2954
> -
> https://elixir.bootlin.com/linux/v6.8-rc5/source/drivers/phy/cadence/phy-=
cadence-torrent.c#L2960
>
> If I add this cleanup in cdns_torrent_phy_configure_multilink(), yes I
> could remove it from cdns_torrent_phy_resume_noirq(), but I should keep
> it in the probe. And I should modify the probe to jump to clk_cleanup if
> cdns_torrent_phy_configure_multilink() fails.

I see it now. If it can't be consolidated, it's not useful to move it
around.

>=20
regards
Philipp