Re: [RFC PATCH v4 net-next 11/23] pinctrl: ocelot: update pinctrl to automatic base address

From: Colin Foster <colin.foster@in-advantage.com>
To: "Clément Léger" <clement.leger@bootlin.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>,
	linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, linux-gpio@vger.kernel.org,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Vladimir Oltean <vladimir.oltean@nxp.com>,
	Claudiu Manoil <claudiu.manoil@nxp.com>,
	UNGLinuxDriver@microchip.com, Andrew Lunn <andrew@lunn.ch>,
	Vivien Didelot <vivien.didelot@gmail.com>,
	Florian Fainelli <f.fainelli@gmail.com>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	Ioana Ciornei <ioana.ciornei@nxp.com>,
	Heiner Kallweit <hkallweit1@gmail.com>,
	Russell King <linux@armlinux.org.uk>,
	Lars Povlsen <lars.povlsen@microchip.com>,
	Steen Hegelund <Steen.Hegelund@microchip.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	Philipp Zabel <p.zabel@pengutronix.de>,
	Heikki Krogerus <heikki.krogerus@linux.intel.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Subject: Re: [RFC PATCH v4 net-next 11/23] pinctrl: ocelot: update pinctrl to automatic base address
Date: Thu, 18 Nov 2021 18:16:24 -0800	[thread overview]
Message-ID: <20211119021624.GB1155@DESKTOP-LAINLKC.localdomain> (raw)
In-Reply-To: <20211117144705.24f21ef1@fixe.home>

On Wed, Nov 17, 2021 at 02:47:05PM +0100, Clément Léger wrote:
> Le Tue, 16 Nov 2021 18:36:33 +0100,
> Alexandre Belloni <alexandre.belloni@bootlin.com> a écrit :
> 
> > Hello,
> > 
> > On 15/11/2021 22:23:16-0800, Colin Foster wrote:
> > > struct gpio_chip recommends passing -1 as base to gpiolib. Doing so avoids
> > > conflicts when the chip is external and gpiochip0 already exists.
> > > 
> > > Signed-off-by: Colin Foster <colin.foster@in-advantage.com>
> > > ---
> > >  drivers/pinctrl/pinctrl-ocelot.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/pinctrl/pinctrl-ocelot.c b/drivers/pinctrl/pinctrl-ocelot.c
> > > index cc7fb0556169..f015404c425c 100644
> > > --- a/drivers/pinctrl/pinctrl-ocelot.c
> > > +++ b/drivers/pinctrl/pinctrl-ocelot.c
> > > @@ -1308,7 +1308,7 @@ static int ocelot_gpiochip_register(struct platform_device *pdev,
> > >  	gc = &info->gpio_chip;
> > >  	gc->ngpio = info->desc->npins;
> > >  	gc->parent = &pdev->dev;
> > > -	gc->base = 0;
> > > +	gc->base = -1;  
> > 
> > I can't remember why but I'm pretty sure I did that on purpose but this
> > indeed cause issues when the chip is external. I've asked Clément to
> > check, let's see what the result is ;)
> 
> After testing, it works on ocelot pcb123 board.

Thank you! Glad to hear it didn't break anything.

> 
> Tested-by: Clément Léger <clement.leger@bootlin.com>
> 
> > 
> > >  	gc->of_node = info->dev->of_node;
> > >  	gc->label = "ocelot-gpio";
> > >  
> > > -- 
> > > 2.25.1
> > >   
> > 
> 
> 
> 
> -- 
> Clément Léger,
> Embedded Linux and Kernel engineer at Bootlin
> https://bootlin.com