[PATCH v1 1/1] gpio: sch: Switch to memory mapped IO accessors

[PATCH v1 1/1] gpio: sch: Switch to memory mapped IO accessors

[Andy Shevchenko]

Convert driver to use memory mapped IO accessors.

Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
---
 drivers/gpio/gpio-sch.c | 25 +++++++++++++++----------
 1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/drivers/gpio/gpio-sch.c b/drivers/gpio/gpio-sch.c
index e48392074e4b8..0c765558d03fc 100644
--- a/drivers/gpio/gpio-sch.c
+++ b/drivers/gpio/gpio-sch.c
@@ -38,8 +38,8 @@
 
 struct sch_gpio {
 	struct gpio_chip chip;
+	void __iomem *regs;
 	spinlock_t lock;
-	unsigned short iobase;
 	unsigned short resume_base;
 
 	/* GPE handling */
@@ -75,7 +75,7 @@ static int sch_gpio_reg_get(struct sch_gpio *sch, unsigned int gpio, unsigned in
 	offset = sch_gpio_offset(sch, gpio, reg);
 	bit = sch_gpio_bit(sch, gpio);
 
-	reg_val = !!(inb(sch->iobase + offset) & BIT(bit));
+	reg_val = !!(ioread8(sch->regs + offset) & BIT(bit));
 
 	return reg_val;
 }
@@ -89,12 +89,14 @@ static void sch_gpio_reg_set(struct sch_gpio *sch, unsigned int gpio, unsigned i
 	offset = sch_gpio_offset(sch, gpio, reg);
 	bit = sch_gpio_bit(sch, gpio);
 
-	reg_val = inb(sch->iobase + offset);
+	reg_val = ioread8(sch->regs + offset);
 
 	if (val)
-		outb(reg_val | BIT(bit), sch->iobase + offset);
+		reg_val |= BIT(bit);
 	else
-		outb((reg_val & ~BIT(bit)), sch->iobase + offset);
+		reg_val &= ~BIT(bit);
+
+	iowrite8(reg_val, sch->regs + offset);
 }
 
 static int sch_gpio_direction_in(struct gpio_chip *gc, unsigned int gpio_num)
@@ -267,8 +269,8 @@ static u32 sch_gpio_gpe_handler(acpi_handle gpe_device, u32 gpe, void *context)
 
 	spin_lock_irqsave(&sch->lock, flags);
 
-	core_status = inl(sch->iobase + CORE_BANK_OFFSET + GTS);
-	resume_status = inl(sch->iobase + RESUME_BANK_OFFSET + GTS);
+	core_status = ioread32(sch->regs + CORE_BANK_OFFSET + GTS);
+	resume_status = ioread32(sch->regs + RESUME_BANK_OFFSET + GTS);
 
 	spin_unlock_irqrestore(&sch->lock, flags);
 
@@ -319,9 +321,11 @@ static int sch_gpio_install_gpe_handler(struct sch_gpio *sch)
 
 static int sch_gpio_probe(struct platform_device *pdev)
 {
+	struct device *dev = &pdev->dev;
 	struct gpio_irq_chip *girq;
 	struct sch_gpio *sch;
 	struct resource *res;
+	void __iomem *regs;
 	int ret;
 
 	sch = devm_kzalloc(&pdev->dev, sizeof(*sch), GFP_KERNEL);
@@ -332,12 +336,13 @@ static int sch_gpio_probe(struct platform_device *pdev)
 	if (!res)
 		return -EBUSY;
 
-	if (!devm_request_region(&pdev->dev, res->start, resource_size(res),
-				 pdev->name))
+	regs = devm_ioport_map(dev, res->start, resource_size(res));
+	if (!regs)
 		return -EBUSY;
 
+	sch->regs = regs;
+
 	spin_lock_init(&sch->lock);
-	sch->iobase = res->start;
 	sch->chip = sch_gpio_chip;
 	sch->chip.label = dev_name(&pdev->dev);
 	sch->chip.parent = &pdev->dev;
-- 
2.44.0

Re: [PATCH v1 1/1] gpio: sch: Switch to memory mapped IO accessors

[Linus Walleij]

On Wed, Apr 10, 2024 at 9:21 AM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:

> Convert driver to use memory mapped IO accessors.
>
> Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>

If this is the direction we want to go with port-mapped I/O then
I'm in.
Acked-by: Linus Walleij <linus.walleij@linaro.org>

An ACK from William may be in order, he's usually keeping track
of the port-mapped stuff.

Yours,
Linus Walleij

Re: [PATCH v1 1/1] gpio: sch: Switch to memory mapped IO accessors

[Andy Shevchenko]

On Fri, Apr 12, 2024 at 10:35:38AM +0200, Linus Walleij wrote:
> On Wed, Apr 10, 2024 at 9:21 AM Andy Shevchenko
> <andy.shevchenko@gmail.com> wrote:
> 
> > Convert driver to use memory mapped IO accessors.
> >
> > Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> 
> If this is the direction we want to go with port-mapped I/O then
> I'm in.
> Acked-by: Linus Walleij <linus.walleij@linaro.org>

Thanks!

> An ACK from William may be in order, he's usually keeping track
> of the port-mapped stuff.

William, are you okay to provide one?

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v1 1/1] gpio: sch: Switch to memory mapped IO accessors

[William Breathitt Gray]

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On Wed, Apr 10, 2024 at 10:21:02AM +0300, Andy Shevchenko wrote:
> Convert driver to use memory mapped IO accessors.
> 
> Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>

Acked-by: William Breathitt Gray <wbg@kernel.org>

A minor suggestion below, but I find this patch accepted as-is.

>  static int sch_gpio_probe(struct platform_device *pdev)
>  {
> +	struct device *dev = &pdev->dev;

In general I think this is a good variable to define to simplify all the
&pdev->dev appearing throughout this callback, but I'd rather have seen
it as its own patch so we could change all the other uses of &pdev->dev
at once without distracting from the memory-mapped I/O change of this
particular patch. Not really necessary, but maybe at some point in the
future a follow-up patch doing such a cleanup would be nice.

William Breathitt Gray

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Re: [PATCH v1 1/1] gpio: sch: Switch to memory mapped IO accessors

[Andy Shevchenko]

On Sat, Apr 13, 2024 at 04:31:26AM -0400, William Breathitt Gray wrote:
> On Wed, Apr 10, 2024 at 10:21:02AM +0300, Andy Shevchenko wrote:
> > Convert driver to use memory mapped IO accessors.
> > 
> > Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> 
> Acked-by: William Breathitt Gray <wbg@kernel.org>

Pushed to my review and testing queue, thank you!

> A minor suggestion below, but I find this patch accepted as-is.
> 
> >  static int sch_gpio_probe(struct platform_device *pdev)
> >  {
> > +	struct device *dev = &pdev->dev;
> 
> In general I think this is a good variable to define to simplify all the
> &pdev->dev appearing throughout this callback, but I'd rather have seen
> it as its own patch so we could change all the other uses of &pdev->dev
> at once without distracting from the memory-mapped I/O change of this
> particular patch. Not really necessary, but maybe at some point in the
> future a follow-up patch doing such a cleanup would be nice.

I avoid making unneeded  churn on a line I have updated in this patch.
That's why I introduced the local variable proactively. Yet, I can do
another patch to clean up the driver based on the existence of this var.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v1 1/1] gpio: sch: Switch to memory mapped IO accessors

[Bartosz Golaszewski]

On Sat, Apr 13, 2024 at 10:31 AM William Breathitt Gray <wbg@kernel.org> wrote:
>
> On Wed, Apr 10, 2024 at 10:21:02AM +0300, Andy Shevchenko wrote:
> > Convert driver to use memory mapped IO accessors.
> >
> > Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
>
> Acked-by: William Breathitt Gray <wbg@kernel.org>
>
> A minor suggestion below, but I find this patch accepted as-is.
>
> >  static int sch_gpio_probe(struct platform_device *pdev)
> >  {
> > +     struct device *dev = &pdev->dev;
>
> In general I think this is a good variable to define to simplify all the
> &pdev->dev appearing throughout this callback, but I'd rather have seen
> it as its own patch so we could change all the other uses of &pdev->dev
> at once without distracting from the memory-mapped I/O change of this
> particular patch. Not really necessary, but maybe at some point in the
> future a follow-up patch doing such a cleanup would be nice.
>
> William Breathitt Gray

I applied it as is, if anyone wants it, this can be sent on top of it.

Bart

Re: [PATCH v1 1/1] gpio: sch: Switch to memory mapped IO accessors

[Andy Shevchenko]

On Wed, Apr 17, 2024 at 12:17 AM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> On Sat, Apr 13, 2024 at 10:31 AM William Breathitt Gray <wbg@kernel.org> wrote:

...

> I applied it as is, if anyone wants it, this can be sent on top of it.

Thanks, but I assumed this should go via my tree and as PR to you. At
least I have it already in my for-next.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v1 1/1] gpio: sch: Switch to memory mapped IO accessors

[Bartosz Golaszewski]

On Wed, Apr 17, 2024 at 10:05 AM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>
> On Wed, Apr 17, 2024 at 12:17 AM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> > On Sat, Apr 13, 2024 at 10:31 AM William Breathitt Gray <wbg@kernel.org> wrote:
>
> ...
>
> > I applied it as is, if anyone wants it, this can be sent on top of it.
>
> Thanks, but I assumed this should go via my tree and as PR to you. At
> least I have it already in my for-next.
>

You didn't respond in any way about picking it up. Can you just drop
it from your branch?

Bart

Re: [PATCH v1 1/1] gpio: sch: Switch to memory mapped IO accessors

[Andy Shevchenko]

On Wed, Apr 17, 2024 at 9:19 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> On Wed, Apr 17, 2024 at 10:05 AM Andy Shevchenko
> <andy.shevchenko@gmail.com> wrote:
> > On Wed, Apr 17, 2024 at 12:17 AM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> > > On Sat, Apr 13, 2024 at 10:31 AM William Breathitt Gray <wbg@kernel.org> wrote:

...

> > > I applied it as is, if anyone wants it, this can be sent on top of it.
> >
> > Thanks, but I assumed this should go via my tree and as PR to you. At
> > least I have it already in my for-next.
>
> You didn't respond in any way about picking it up.

Hmm... I'm the author of it and I'm a maintainer for that driver. I'm
not sure if it's mandatory to respond for that purpose. Usually I
asked the opposite, i.e. when I'm not going to pick the thing up.

> Can you just drop
> it from your branch?

It's possible, but I will need to rebase, which is not a good thing to
perform. What about just leaving it as is and letting git to (nicely)
solve this?

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v1 1/1] gpio: sch: Switch to memory mapped IO accessors

[Bartosz Golaszewski]

On Wed, Apr 17, 2024 at 10:41 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>
> On Wed, Apr 17, 2024 at 9:19 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> > On Wed, Apr 17, 2024 at 10:05 AM Andy Shevchenko
> > <andy.shevchenko@gmail.com> wrote:
> > > On Wed, Apr 17, 2024 at 12:17 AM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> > > > On Sat, Apr 13, 2024 at 10:31 AM William Breathitt Gray <wbg@kernel.org> wrote:
>
> ...
>
> > > > I applied it as is, if anyone wants it, this can be sent on top of it.
> > >
> > > Thanks, but I assumed this should go via my tree and as PR to you. At
> > > least I have it already in my for-next.
> >
> > You didn't respond in any way about picking it up.
>
> Hmm... I'm the author of it and I'm a maintainer for that driver. I'm
> not sure if it's mandatory to respond for that purpose. Usually I
> asked the opposite, i.e. when I'm not going to pick the thing up.
>
> > Can you just drop
> > it from your branch?
>
> It's possible, but I will need to rebase, which is not a good thing to
> perform. What about just leaving it as is and letting git to (nicely)
> solve this?
>
> --
> With Best Regards,
> Andy Shevchenko

It won't be solved nicely, we'll get a warning about the same commit
appearing twice with different hashes.

Whatever, I dropped it from my tree, it was the HEAD anyway.

Bart

Re: [PATCH v1 1/1] gpio: sch: Switch to memory mapped IO accessors

[Andy Shevchenko]

On Wed, Apr 17, 2024 at 11:46 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> On Wed, Apr 17, 2024 at 10:41 PM Andy Shevchenko
> <andy.shevchenko@gmail.com> wrote:
> > On Wed, Apr 17, 2024 at 9:19 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> > > On Wed, Apr 17, 2024 at 10:05 AM Andy Shevchenko
> > > <andy.shevchenko@gmail.com> wrote:
> > > > On Wed, Apr 17, 2024 at 12:17 AM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> > > > > On Sat, Apr 13, 2024 at 10:31 AM William Breathitt Gray <wbg@kernel.org> wrote:

...

> > > > > I applied it as is, if anyone wants it, this can be sent on top of it.
> > > >
> > > > Thanks, but I assumed this should go via my tree and as PR to you. At
> > > > least I have it already in my for-next.
> > >
> > > You didn't respond in any way about picking it up.
> >
> > Hmm... I'm the author of it and I'm a maintainer for that driver. I'm
> > not sure if it's mandatory to respond for that purpose. Usually I
> > asked the opposite, i.e. when I'm not going to pick the thing up.
> >
> > > Can you just drop
> > > it from your branch?
> >
> > It's possible, but I will need to rebase, which is not a good thing to
> > perform. What about just leaving it as is and letting git to (nicely)
> > solve this?
>
> It won't be solved nicely, we'll get a warning about the same commit
> appearing twice with different hashes.

Oh, this sounds like a new check in Linux Next? Or somewhere else?

> Whatever, I dropped it from my tree, it was the HEAD anyway.

Thank you!

-- 
With Best Regards,
Andy Shevchenko