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[PATCH v5 2/2] gpio: mlxbf3: Support add_pin_ranges()

Asmaa Mnebhi posted 2 patches 2 years, 4 months ago
[PATCH v5 2/2] gpio: mlxbf3: Support add_pin_ranges()
Posted by Asmaa Mnebhi 2 years, 4 months ago 
Support add_pin_ranges() so that pinctrl_gpio_request() can be called.
The GPIO value is not modified when the user runs the "gpioset" tool.
This is because when gpiochip_generic_request is invoked by the gpio-mlxbf3
driver, "pin_ranges" is empty so it skips "pinctrl_gpio_request()".
pinctrl_gpio_request() is essential in the code flow because it changes the
mux value so that software has control over modifying the GPIO value.
Adding add_pin_ranges() creates a dependency on the pinctrl-mlxbf3.c driver.

Fixes: cd33f216d24 ("gpio: mlxbf3: Add gpio driver support")
Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
---
v4->v5:
- Add "Reviewed-By" Tag
v3->v4:
- Drop the common define for MLXBF3_GPIO_MAX_PINS_BLOCK0
v2->v3:
- Replace boolean logic by clear switch statement logic in
  mlxbf3_gpio_add_pin_ranges()
v1->v2:
- Cleanup mlxbf3_gpio_add_pin_ranges()

 drivers/gpio/gpio-mlxbf3.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/gpio/gpio-mlxbf3.c b/drivers/gpio/gpio-mlxbf3.c
index e30cee108986..0a5f241a8352 100644
--- a/drivers/gpio/gpio-mlxbf3.c
+++ b/drivers/gpio/gpio-mlxbf3.c
@@ -19,6 +19,8 @@
  * gpio[1]: HOST_GPIO32->HOST_GPIO55
  */
 #define MLXBF3_GPIO_MAX_PINS_PER_BLOCK 32
+#define MLXBF3_GPIO_MAX_PINS_BLOCK0    32
+#define MLXBF3_GPIO_MAX_PINS_BLOCK1    24
 
 /*
  * fw_gpio[x] block registers and their offset
@@ -158,6 +160,26 @@ static const struct irq_chip gpio_mlxbf3_irqchip = {
 	GPIOCHIP_IRQ_RESOURCE_HELPERS,
 };
 
+static int mlxbf3_gpio_add_pin_ranges(struct gpio_chip *chip)
+{
+	unsigned int id;
+
+	switch(chip->ngpio) {
+	case MLXBF3_GPIO_MAX_PINS_BLOCK0:
+		id = 0;
+		break;
+	case MLXBF3_GPIO_MAX_PINS_BLOCK1:
+		id = 1;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return gpiochip_add_pin_range(chip, "MLNXBF34:00",
+			chip->base, id * MLXBF3_GPIO_MAX_PINS_PER_BLOCK,
+			chip->ngpio);
+}
+
 static int mlxbf3_gpio_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -197,6 +219,7 @@ static int mlxbf3_gpio_probe(struct platform_device *pdev)
 	gc->request = gpiochip_generic_request;
 	gc->free = gpiochip_generic_free;
 	gc->owner = THIS_MODULE;
+	gc->add_pin_ranges = mlxbf3_gpio_add_pin_ranges;
 
 	irq = platform_get_irq(pdev, 0);
 	if (irq >= 0) {
@@ -243,6 +266,7 @@ static struct platform_driver mlxbf3_gpio_driver = {
 };
 module_platform_driver(mlxbf3_gpio_driver);
 
+MODULE_SOFTDEP("pre: pinctrl-mlxbf3");
 MODULE_DESCRIPTION("NVIDIA BlueField-3 GPIO Driver");
 MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>");
 MODULE_LICENSE("Dual BSD/GPL");
-- 
2.30.1
Re: [PATCH v5 2/2] gpio: mlxbf3: Support add_pin_ranges()
Posted by Bartosz Golaszewski 2 years, 3 months ago 
On Fri, Aug 18, 2023 at 6:43 PM Asmaa Mnebhi <asmaa@nvidia.com> wrote:
>
> Support add_pin_ranges() so that pinctrl_gpio_request() can be called.
> The GPIO value is not modified when the user runs the "gpioset" tool.
> This is because when gpiochip_generic_request is invoked by the gpio-mlxbf3
> driver, "pin_ranges" is empty so it skips "pinctrl_gpio_request()".
> pinctrl_gpio_request() is essential in the code flow because it changes the
> mux value so that software has control over modifying the GPIO value.
> Adding add_pin_ranges() creates a dependency on the pinctrl-mlxbf3.c driver.
>
> Fixes: cd33f216d24 ("gpio: mlxbf3: Add gpio driver support")
> Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> ---
> v4->v5:
> - Add "Reviewed-By" Tag
> v3->v4:
> - Drop the common define for MLXBF3_GPIO_MAX_PINS_BLOCK0
> v2->v3:
> - Replace boolean logic by clear switch statement logic in
>   mlxbf3_gpio_add_pin_ranges()
> v1->v2:
> - Cleanup mlxbf3_gpio_add_pin_ranges()
>
>  drivers/gpio/gpio-mlxbf3.c | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
>
> diff --git a/drivers/gpio/gpio-mlxbf3.c b/drivers/gpio/gpio-mlxbf3.c
> index e30cee108986..0a5f241a8352 100644
> --- a/drivers/gpio/gpio-mlxbf3.c
> +++ b/drivers/gpio/gpio-mlxbf3.c
> @@ -19,6 +19,8 @@
>   * gpio[1]: HOST_GPIO32->HOST_GPIO55
>   */
>  #define MLXBF3_GPIO_MAX_PINS_PER_BLOCK 32
> +#define MLXBF3_GPIO_MAX_PINS_BLOCK0    32
> +#define MLXBF3_GPIO_MAX_PINS_BLOCK1    24
>
>  /*
>   * fw_gpio[x] block registers and their offset
> @@ -158,6 +160,26 @@ static const struct irq_chip gpio_mlxbf3_irqchip = {
>         GPIOCHIP_IRQ_RESOURCE_HELPERS,
>  };
>
> +static int mlxbf3_gpio_add_pin_ranges(struct gpio_chip *chip)
> +{
> +       unsigned int id;
> +
> +       switch(chip->ngpio) {
> +       case MLXBF3_GPIO_MAX_PINS_BLOCK0:
> +               id = 0;
> +               break;
> +       case MLXBF3_GPIO_MAX_PINS_BLOCK1:
> +               id = 1;
> +               break;
> +       default:
> +               return -EINVAL;
> +       }
> +
> +       return gpiochip_add_pin_range(chip, "MLNXBF34:00",
> +                       chip->base, id * MLXBF3_GPIO_MAX_PINS_PER_BLOCK,
> +                       chip->ngpio);
> +}
> +
>  static int mlxbf3_gpio_probe(struct platform_device *pdev)
>  {
>         struct device *dev = &pdev->dev;
> @@ -197,6 +219,7 @@ static int mlxbf3_gpio_probe(struct platform_device *pdev)
>         gc->request = gpiochip_generic_request;
>         gc->free = gpiochip_generic_free;
>         gc->owner = THIS_MODULE;
> +       gc->add_pin_ranges = mlxbf3_gpio_add_pin_ranges;
>
>         irq = platform_get_irq(pdev, 0);
>         if (irq >= 0) {
> @@ -243,6 +266,7 @@ static struct platform_driver mlxbf3_gpio_driver = {
>  };
>  module_platform_driver(mlxbf3_gpio_driver);
>
> +MODULE_SOFTDEP("pre: pinctrl-mlxbf3");
>  MODULE_DESCRIPTION("NVIDIA BlueField-3 GPIO Driver");
>  MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>");
>  MODULE_LICENSE("Dual BSD/GPL");
> --
> 2.30.1
>

It's not clear to me whether this depends on patch 1? If only at
run-time then I guess Linus and I can take the two patches through
ours respective trees?

Bart
RE: [PATCH v5 2/2] gpio: mlxbf3: Support add_pin_ranges()
Posted by Asmaa Mnebhi 2 years, 3 months ago 
> > +MODULE_SOFTDEP("pre: pinctrl-mlxbf3");
> >  MODULE_DESCRIPTION("NVIDIA BlueField-3 GPIO Driver");
> > MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>");
> > MODULE_LICENSE("Dual BSD/GPL");
> > --
> > 2.30.1
> >
> 
> It's not clear to me whether this depends on patch 1? If only at run-time then I
> guess Linus and I can take the two patches through ours respective trees?

Indeed from a build point of view, there is no dependency so you could take the 2 patches through your respective tree. However, at run-time, the gpio-mlxbf3.c driver fails to load without the pinctrl-mlxbf3.c driver. Should I add a "depends on" in the Kconfig? Then you will have to include both patches in your tree.

Thanks.
Asmaa
Re: [PATCH v5 2/2] gpio: mlxbf3: Support add_pin_ranges()
Posted by Bartosz Golaszewski 2 years, 3 months ago 
On Mon, Aug 21, 2023 at 2:55 PM Asmaa Mnebhi <asmaa@nvidia.com> wrote:
>
> > > +MODULE_SOFTDEP("pre: pinctrl-mlxbf3");
> > >  MODULE_DESCRIPTION("NVIDIA BlueField-3 GPIO Driver");
> > > MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>");
> > > MODULE_LICENSE("Dual BSD/GPL");
> > > --
> > > 2.30.1
> > >
> >
> > It's not clear to me whether this depends on patch 1? If only at run-time then I
> > guess Linus and I can take the two patches through ours respective trees?
>
> Indeed from a build point of view, there is no dependency so you could take the 2 patches through your respective tree. However, at run-time, the gpio-mlxbf3.c driver fails to load without the pinctrl-mlxbf3.c driver. Should I add a "depends on" in the Kconfig? Then you will have to include both patches in your tree.
>

Linus, are you fine with me taking this patch? It will not break the
build and with you taking the other one, next will be fine too.

Bart
Re: [PATCH v5 2/2] gpio: mlxbf3: Support add_pin_ranges()
Posted by Linus Walleij 2 years, 3 months ago 
On Mon, Aug 21, 2023 at 5:04 PM Bartosz Golaszewski <brgl@bgdev.pl> wrote:
> On Mon, Aug 21, 2023 at 2:55 PM Asmaa Mnebhi <asmaa@nvidia.com> wrote:
> >
> > > > +MODULE_SOFTDEP("pre: pinctrl-mlxbf3");
> > > >  MODULE_DESCRIPTION("NVIDIA BlueField-3 GPIO Driver");
> > > > MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>");
> > > > MODULE_LICENSE("Dual BSD/GPL");
> > > > --
> > > > 2.30.1
> > > >
> > >
> > > It's not clear to me whether this depends on patch 1? If only at run-time then I
> > > guess Linus and I can take the two patches through ours respective trees?
> >
> > Indeed from a build point of view, there is no dependency so you could take the 2 patches through your respective tree. However, at run-time, the gpio-mlxbf3.c driver fails to load without the pinctrl-mlxbf3.c driver. Should I add a "depends on" in the Kconfig? Then you will have to include both patches in your tree.
> >
>
> Linus, are you fine with me taking this patch? It will not break the
> build and with you taking the other one, next will be fine too.

Yep pick this one, I applied 1/2 to the pinctrl tree now.

Yours,
Linus Walleij

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