Date: Wed, 27 Sep 2017 13:29:22 +0200
From: Petr Mladek <pmladek@suse.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org,
        Daniel Drake <drake@endlessm.com>,
        Linus Walleij <linus.walleij@linaro.org>
Subject: Re: [PATCH 4.13 015/109] pinctrl/amd: save pin registers over
 suspend/resume
Message-ID: <20170927112922.GK21048@pathway.suse.cz>
References: <20170924203353.104695385@linuxfoundation.org>
 <20170924203353.715364287@linuxfoundation.org>
 <20170926140745.GC13820@pathway.suse.cz>
 <20170927083926.GB20317@kroah.com>
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On Wed 2017-09-27 10:39:26, Greg Kroah-Hartman wrote:
> On Tue, Sep 26, 2017 at 04:07:45PM +0200, Petr Mladek wrote:
> > On Sun 2017-09-24 22:32:36, Greg Kroah-Hartman wrote:
> > > 4.13-stable review patch.  If anyone has any objections, please let me know.
> > > 
> > > ------------------
> > > 
> > > From: Daniel Drake <drake@endlessm.com>
> > > 
> > > commit 79d2c8bede2c93f9432d7da0bc2f76a195c90fc0 upstream.
> > > 
> > > The touchpad in the Asus laptop models X505BA/BP and X542BA/BP is
> > > unresponsive after suspend/resume. The following error appears during
> > > resume:
> > > 
> > >   i2c_hid i2c-ELAN1300:00: failed to reset device.
> > > 
> > > The problem here is that i2c_hid does not notice the interrupt being
> > > generated at this point, because the GPIO is no longer configured
> > > for interrupts.
> > > 
> > > Fix this by saving pinctrl-amd pin registers during suspend and
> > > restoring them at resume time.
> > > 
> > > Based on code from pinctrl-intel.
> > > 
> > > Signed-off-by: Daniel Drake <drake@endlessm.com>
> > > Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> > > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > > 
> > > --- a/drivers/pinctrl/pinctrl-amd.c
> > > +++ b/drivers/pinctrl/pinctrl-amd.c
> > > @@ -725,6 +726,69 @@ static const struct pinconf_ops amd_pinc
> > >  	.pin_config_group_set = amd_pinconf_group_set,
> > >  };
> > >  
> > > +#ifdef CONFIG_PM_SLEEP
> > > +static bool amd_gpio_should_save(struct amd_gpio *gpio_dev, unsigned int pin)
> > > +{
> > > +	const struct pin_desc *pd = pin_desc_get(gpio_dev->pctrl, pin);
> > > +
> > > +	if (!pd)
> > > +		return false;
> > > +
> > > +	/*
> > > +	 * Only restore the pin if it is actually in use by the kernel (or
> > > +	 * by userspace).
> > > +	 */
> > > +	if (pd->mux_owner || pd->gpio_owner ||
> > 
> > This code causes a compilation error in the current Linus' tree
> > (4.14-rc2+). I guess that the same problem will be also in
> > older trees.
> > 
> > IMHO, we need to select CONFIG_PINMUX for when CONFIG_PINCTRL_AMD
> > is selected. The following patch helped here:
> > 
> > >From f83130d3b5c147b4d400922847ca2751d8020ab5 Mon Sep 17 00:00:00 2001
> > From: Petr Mladek <pmladek@suse.com>
> > Date: Tue, 26 Sep 2017 15:51:28 +0200
> > Subject: [PATCH] pinctrl/amd: Fix build dependency on pinmux code
> > MIME-Version: 1.0
> > Content-Type: text/plain; charset=UTF-8
> > Content-Transfer-Encoding: 8bit
> > 
> > The commit 79d2c8bede2c93f943 ("pinctrl/amd: save pin registers over
> > suspend/resume") caused the following compilation errors:
> > 
> > drivers/pinctrl/pinctrl-amd.c: In function ‘amd_gpio_should_save’:
> > drivers/pinctrl/pinctrl-amd.c:741:8: error: ‘const struct pin_desc’ has no member named ‘mux_owner’
> >   if (pd->mux_owner || pd->gpio_owner ||
> >         ^
> > drivers/pinctrl/pinctrl-amd.c:741:25: error: ‘const struct pin_desc’ has no member named ‘gpio_owner’
> >   if (pd->mux_owner || pd->gpio_owner ||
> > 
> > We need to enable CONFIG_PINMUX for this driver as well.
> > 
> > Fixes: 79d2c8bede2c93f943 ("pinctrl/amd: save pin registers over suspend/resume")
> > Signed-off-by: Petr Mladek <pmladek@suse.com>
> > ---
> >  drivers/pinctrl/Kconfig | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
> > index 1778cf4f81c7..82cd8b08d71f 100644
> > --- a/drivers/pinctrl/Kconfig
> > +++ b/drivers/pinctrl/Kconfig
> > @@ -100,6 +100,7 @@ config PINCTRL_AMD
> >  	tristate "AMD GPIO pin control"
> >  	depends on GPIOLIB
> >  	select GPIOLIB_IRQCHIP
> > +	select PINMUX
> >  	select PINCONF
> >  	select GENERIC_PINCONF
> >  	help
> > -- 
> > 1.8.5.6
> 
> What is the commit id for this patch in Linus's tree?  I don't see it
> there...

This extra patch has not been pushed to the Linus' tree yet.
It was only my proposal to fix the problem. I did not find
the original patch discussed on the kernel mailing list.
Therefore I sent this follow up fix as a reply to
the 4.13-stable review mail.

I hope that Linus Walleij would notice, review, and push it
into Linus' tree.

Best Regards,
Petr