[PATCH v2 0/5] rsk7203: switch to using static device property, drop legacy gpio API

[PATCH v2 0/5] rsk7203: switch to using static device property, drop legacy gpio API

[Dmitry Torokhov]

This series of patches converts rsk7203 to use static device properties
for its devices, including gpio-keys and gpio-leds, and removing
dependency on legacy gpio API (in favor of gpiod API).

To configure pin functions the board is switched to use gpio-hogs, as
doing full conversion to pinmux is too challenging without access to
hardware.

v2:
- Added a patch to isolate the function gpiochip from the parent fwnode
  to prevent ambiguous property lookups
- Added a patch attaching a software node to the main PFC gpiochip device
- Adjusted the board setup to use the PFC's software node for LEDs and
  GPIO keys instead of creating a standalone node
- Added support to sh-pfc for configuring the secondary "function"
  gpiochip via a "functions" child software node.
- Converted board pin configuration from legacy gpio_request() to GPIO
  hogs, using postcore_initcall to ensure nodes are available during
  driver probe.

v1:

http://lore.kernel.org/r/jwtdoptatzfo47mbpmmjwhhhjn4mbw6ekp4gtoopca7azbcelo@uvtz4w2ga5qn

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
Dmitry Torokhov (5):
      pinctrl: renesas: gpio: isolate function gpiochip from parent fwnode
      sh: pfc: attach software node to the GPIO chip
      sh: mach-rsk: rsk7203: use static device properties for LEDs and GPIO buttons
      pinctrl: renesas: gpio: support software nodes for function GPIOs
      sh: mach-rsk: rsk7203: convert pin configuration to using software nodes

 arch/sh/boards/mach-rsk/devices-rsk7203.c | 282 ++++++++++++++++++++++--------
 arch/sh/include/cpu-common/cpu/pfc.h      |   3 +
 arch/sh/kernel/cpu/pfc.c                  |  20 ++-
 drivers/pinctrl/renesas/gpio.c            |  28 +++
 4 files changed, 254 insertions(+), 79 deletions(-)
---
base-commit: 6a50ba100ace43f43c87384367eb2d2605fcc16c
change-id: 20260310-rsk7203-properties-82bf2c12b985

Thanks.

-- 
Dmitry

[PATCH v2 1/5] pinctrl: renesas: gpio: isolate function gpiochip from parent fwnode

[Dmitry Torokhov]

The sh-pfc driver registers two separate gpiochip instances: one for
real GPIOs and another for function GPIOs. Since both share the same
parent platform device, gpiolib's fallback logic causes both chips to
share the same firmware node (fwnode).

This causes ambiguity when using software nodes to describe GPIOs, as
gpiolib may apply hogs meant for one chip to the other if they share the
same node.

Explicitly set gc->fwnode to ERR_PTR(-ENODEV) for the function GPIO
chip. This satisfies gpiolib's check for an existing fwnode and prevents
it from falling back to the parent device's node, while ensuring that no
actual properties or hogs are found on the function chip unless
explicitly assigned later.

Assisted-by: Gemini:gemini-3.1-pro
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/pinctrl/renesas/gpio.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/pinctrl/renesas/gpio.c b/drivers/pinctrl/renesas/gpio.c
index 2293af642849..4e59dadb7364 100644
--- a/drivers/pinctrl/renesas/gpio.c
+++ b/drivers/pinctrl/renesas/gpio.c
@@ -278,6 +278,12 @@ static int gpio_function_setup(struct sh_pfc_chip *chip)
 
 	gc->request = gpio_function_request;
 
+	/*
+	 * Explicitly mask the parent's fwnode to prevent gpiolib from
+	 * reusing it for function GPIOs.
+	 */
+	gc->fwnode = ERR_PTR(-ENODEV);
+
 	gc->label = pfc->info->name;
 	gc->owner = THIS_MODULE;
 	gc->base = pfc->nr_gpio_pins;

-- 
2.54.0.669.g59709faab0-goog

Re: [PATCH v2 1/5] pinctrl: renesas: gpio: isolate function gpiochip from parent fwnode

[Bartosz Golaszewski]

On Thu, 21 May 2026 07:13:17 +0200, Dmitry Torokhov
<dmitry.torokhov@gmail.com> said:
> The sh-pfc driver registers two separate gpiochip instances: one for
> real GPIOs and another for function GPIOs. Since both share the same
> parent platform device, gpiolib's fallback logic causes both chips to
> share the same firmware node (fwnode).
>
> This causes ambiguity when using software nodes to describe GPIOs, as
> gpiolib may apply hogs meant for one chip to the other if they share the
> same node.
>
> Explicitly set gc->fwnode to ERR_PTR(-ENODEV) for the function GPIO
> chip. This satisfies gpiolib's check for an existing fwnode and prevents
> it from falling back to the parent device's node, while ensuring that no
> actual properties or hogs are found on the function chip unless
> explicitly assigned later.
>
> Assisted-by: Gemini:gemini-3.1-pro
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> ---
>  drivers/pinctrl/renesas/gpio.c | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/drivers/pinctrl/renesas/gpio.c b/drivers/pinctrl/renesas/gpio.c
> index 2293af642849..4e59dadb7364 100644
> --- a/drivers/pinctrl/renesas/gpio.c
> +++ b/drivers/pinctrl/renesas/gpio.c
> @@ -278,6 +278,12 @@ static int gpio_function_setup(struct sh_pfc_chip *chip)
>
>  	gc->request = gpio_function_request;
>
> +	/*
> +	 * Explicitly mask the parent's fwnode to prevent gpiolib from
> +	 * reusing it for function GPIOs.
> +	 */
> +	gc->fwnode = ERR_PTR(-ENODEV);
> +
>  	gc->label = pfc->info->name;
>  	gc->owner = THIS_MODULE;
>  	gc->base = pfc->nr_gpio_pins;
>
> --
> 2.54.0.669.g59709faab0-goog
>
>

Acked-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Should we document this behavior in struct gpio_chip's kerneldoc?

Bartosz

[PATCH v2 2/5] sh: pfc: attach software node to the GPIO chip

[Dmitry Torokhov]

With commit e5d527be7e69 ("gpio: swnode: don't use the swnode's name as
the key for GPIO lookup") gpiolib requires that firmware nodes from the
GPIO references to match firmware node in gpiochip structure.

Define a software node for the pfc gpiochip so that it can be referenced
by boards using static device properties.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 arch/sh/include/cpu-common/cpu/pfc.h |  3 +++
 arch/sh/kernel/cpu/pfc.c             | 20 ++++++++++++++------
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/arch/sh/include/cpu-common/cpu/pfc.h b/arch/sh/include/cpu-common/cpu/pfc.h
index 879d2c9da537..d57e38c05bdb 100644
--- a/arch/sh/include/cpu-common/cpu/pfc.h
+++ b/arch/sh/include/cpu-common/cpu/pfc.h
@@ -11,6 +11,9 @@
 #include <linux/types.h>
 
 struct resource;
+struct software_node;
+
+extern const struct software_node pfc_gpiochip_node;
 
 int sh_pfc_register(const char *name,
 		    struct resource *resource, u32 num_resources);
diff --git a/arch/sh/kernel/cpu/pfc.c b/arch/sh/kernel/cpu/pfc.c
index 062056ede88d..5a8d804d607b 100644
--- a/arch/sh/kernel/cpu/pfc.c
+++ b/arch/sh/kernel/cpu/pfc.c
@@ -5,21 +5,29 @@
  * Copyright (C) 2012  Renesas Solutions Corp.
  */
 
+#include <linux/err.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
 
 #include <cpu/pfc.h>
 
-static struct platform_device sh_pfc_device = {
-	.id		= -1,
+const struct software_node pfc_gpiochip_node = {
+	.name = "sh-pfc",
 };
 
 int __init sh_pfc_register(const char *name,
 			   struct resource *resource, u32 num_resources)
 {
-	sh_pfc_device.name = name;
-	sh_pfc_device.num_resources = num_resources;
-	sh_pfc_device.resource = resource;
+	struct platform_device_info pdev_info = {
+		.name		= name,
+		.id		= PLATFORM_DEVID_NONE,
+		.res		= resource,
+		.num_res	= num_resources,
+		.swnode		= &pfc_gpiochip_node,
+	};
+	struct platform_device *pdev;
 
-	return platform_device_register(&sh_pfc_device);
+	pdev = platform_device_register_full(&pdev_info);
+	return PTR_ERR_OR_ZERO(pdev);
 }

-- 
2.54.0.669.g59709faab0-goog

Re: [PATCH v2 2/5] sh: pfc: attach software node to the GPIO chip

[Bartosz Golaszewski]

On Thu, 21 May 2026 07:13:18 +0200, Dmitry Torokhov
<dmitry.torokhov@gmail.com> said:
> With commit e5d527be7e69 ("gpio: swnode: don't use the swnode's name as
> the key for GPIO lookup") gpiolib requires that firmware nodes from the
> GPIO references to match firmware node in gpiochip structure.
>
> Define a software node for the pfc gpiochip so that it can be referenced
> by boards using static device properties.
>
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

[PATCH v2 3/5] sh: mach-rsk: rsk7203: use static device properties for LEDs and GPIO buttons

[Dmitry Torokhov]

Convert the board to use static device properties instead of platform
data to describe LEDs and GPIO-connected buttons on the board, so
that support for platform data can be removed from gpio-keys and other
drivers, unifying their behavior.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 arch/sh/boards/mach-rsk/devices-rsk7203.c | 199 ++++++++++++++++++++----------
 1 file changed, 131 insertions(+), 68 deletions(-)

diff --git a/arch/sh/boards/mach-rsk/devices-rsk7203.c b/arch/sh/boards/mach-rsk/devices-rsk7203.c
index e6b05d4588b7..f8760a91e2f1 100644
--- a/arch/sh/boards/mach-rsk/devices-rsk7203.c
+++ b/arch/sh/boards/mach-rsk/devices-rsk7203.c
@@ -4,17 +4,19 @@
  *
  * Copyright (C) 2008 - 2010  Paul Mundt
  */
+#include <linux/err.h>
 #include <linux/init.h>
 #include <linux/types.h>
 #include <linux/platform_device.h>
 #include <linux/interrupt.h>
 #include <linux/smsc911x.h>
 #include <linux/input.h>
+#include <linux/io.h>
 #include <linux/gpio.h>
-#include <linux/gpio_keys.h>
-#include <linux/leds.h>
+#include <linux/gpio/machine.h>
+#include <linux/gpio/property.h>
 #include <asm/machvec.h>
-#include <asm/io.h>
+#include <cpu/pfc.h>
 #include <cpu/sh7203.h>
 
 static struct smsc911x_platform_config smsc911x_config = {
@@ -37,92 +39,138 @@ static struct resource smsc911x_resources[] = {
 	},
 };
 
-static struct platform_device smsc911x_device = {
-	.name		= "smsc911x",
-	.id		= -1,
-	.num_resources	= ARRAY_SIZE(smsc911x_resources),
-	.resource	= smsc911x_resources,
-	.dev		= {
-		.platform_data = &smsc911x_config,
+static const struct software_node rsk7203_gpio_leds_node = {
+	.name = "rsk7203-gpio-leds",
+};
+
+static const struct software_node rsk7203_green_led_node = {
+	.name = "green",
+	.parent = &rsk7203_gpio_leds_node,
+	.properties = (const struct property_entry[]) {
+		PROPERTY_ENTRY_STRING("label", "green"),
+		PROPERTY_ENTRY_GPIO("gpios", &pfc_gpiochip_node,
+				    GPIO_PE10, GPIO_ACTIVE_LOW),
+		{ }
 	},
 };
 
-static struct gpio_led rsk7203_gpio_leds[] = {
-	{
-		.name			= "green",
-		.gpio			= GPIO_PE10,
-		.active_low		= 1,
-	}, {
-		.name			= "orange",
-		.default_trigger	= "nand-disk",
-		.gpio			= GPIO_PE12,
-		.active_low		= 1,
-	}, {
-		.name			= "red:timer",
-		.default_trigger	= "timer",
-		.gpio			= GPIO_PC14,
-		.active_low		= 1,
-	}, {
-		.name			= "red:heartbeat",
-		.default_trigger	= "heartbeat",
-		.gpio			= GPIO_PE11,
-		.active_low		= 1,
+static const struct software_node rsk7203_orange_led_node = {
+	.name = "orange",
+	.parent = &rsk7203_gpio_leds_node,
+	.properties = (const struct property_entry[]) {
+		PROPERTY_ENTRY_STRING("label", "orange"),
+		PROPERTY_ENTRY_STRING("linux,default-trigger", "nand-disk"),
+		PROPERTY_ENTRY_GPIO("gpios", &pfc_gpiochip_node,
+				    GPIO_PE12, GPIO_ACTIVE_LOW),
+		{ }
 	},
 };
 
-static struct gpio_led_platform_data rsk7203_gpio_leds_info = {
-	.leds		= rsk7203_gpio_leds,
-	.num_leds	= ARRAY_SIZE(rsk7203_gpio_leds),
+static const struct software_node rsk7203_red1_led_node = {
+	.name = "red:timer",
+	.parent = &rsk7203_gpio_leds_node,
+	.properties = (const struct property_entry[]) {
+		PROPERTY_ENTRY_STRING("label", "red:timer"),
+		PROPERTY_ENTRY_STRING("linux,default-trigger", "timer"),
+		PROPERTY_ENTRY_GPIO("gpios", &pfc_gpiochip_node,
+				    GPIO_PC14, GPIO_ACTIVE_LOW),
+		{ }
+	},
 };
 
-static struct platform_device led_device = {
-	.name		= "leds-gpio",
-	.id		= -1,
-	.dev		= {
-		.platform_data	= &rsk7203_gpio_leds_info,
+static const struct software_node rsk7203_red2_led_node = {
+	.name = "red:heartbeat",
+	.parent = &rsk7203_gpio_leds_node,
+	.properties = (const struct property_entry[]) {
+		PROPERTY_ENTRY_STRING("label", "red:heartbeat"),
+		PROPERTY_ENTRY_STRING("linux,default-trigger", "heartbeat"),
+		PROPERTY_ENTRY_GPIO("gpios", &pfc_gpiochip_node,
+				    GPIO_PE11, GPIO_ACTIVE_LOW),
+		{ }
 	},
 };
 
-static struct gpio_keys_button rsk7203_gpio_keys_table[] = {
-	{
-		.code		= BTN_0,
-		.gpio		= GPIO_PB0,
-		.active_low	= 1,
-		.desc		= "SW1",
-	}, {
-		.code		= BTN_1,
-		.gpio		= GPIO_PB1,
-		.active_low	= 1,
-		.desc		= "SW2",
-	}, {
-		.code		= BTN_2,
-		.gpio		= GPIO_PB2,
-		.active_low	= 1,
-		.desc		= "SW3",
+static const struct software_node rsk7203_gpio_keys_node = {
+	.name = "rsk7203-gpio-keys",
+	.properties = (const struct property_entry[]) {
+		PROPERTY_ENTRY_U32("poll-interval", 50),
+		{ }
 	},
 };
 
-static struct gpio_keys_platform_data rsk7203_gpio_keys_info = {
-	.buttons	= rsk7203_gpio_keys_table,
-	.nbuttons	= ARRAY_SIZE(rsk7203_gpio_keys_table),
-	.poll_interval	= 50, /* default to 50ms */
+static const struct software_node rsk7203_sw1_key_node = {
+	.parent = &rsk7203_gpio_keys_node,
+	.properties = (const struct property_entry[]) {
+		PROPERTY_ENTRY_U32("linux,code", BTN_0),
+		PROPERTY_ENTRY_GPIO("gpios", &pfc_gpiochip_node,
+				    GPIO_PB0, GPIO_ACTIVE_LOW),
+		PROPERTY_ENTRY_STRING("label", "SW1"),
+		{ }
+	},
 };
 
-static struct platform_device keys_device = {
-	.name		= "gpio-keys-polled",
-	.dev		= {
-		.platform_data	= &rsk7203_gpio_keys_info,
+static const struct software_node rsk7203_sw2_key_node = {
+	.parent = &rsk7203_gpio_keys_node,
+	.properties = (const struct property_entry[]) {
+		PROPERTY_ENTRY_U32("linux,code", BTN_1),
+		PROPERTY_ENTRY_GPIO("gpios", &pfc_gpiochip_node,
+				    GPIO_PB1, GPIO_ACTIVE_LOW),
+		PROPERTY_ENTRY_STRING("label", "SW2"),
+		{ }
 	},
 };
 
-static struct platform_device *rsk7203_devices[] __initdata = {
-	&smsc911x_device,
-	&led_device,
-	&keys_device,
+static const struct software_node rsk7203_sw3_key_node = {
+	.parent = &rsk7203_gpio_keys_node,
+	.properties = (const struct property_entry[]) {
+		PROPERTY_ENTRY_U32("linux,code", BTN_2),
+		PROPERTY_ENTRY_GPIO("gpios", &pfc_gpiochip_node,
+				    GPIO_PB2, GPIO_ACTIVE_LOW),
+		PROPERTY_ENTRY_STRING("label", "SW3"),
+		{ }
+	},
+};
+
+static const struct software_node * const rsk7203_swnodes[] __initconst = {
+	&rsk7203_gpio_leds_node,
+	&rsk7203_green_led_node,
+	&rsk7203_orange_led_node,
+	&rsk7203_red1_led_node,
+	&rsk7203_red2_led_node,
+	&rsk7203_gpio_keys_node,
+	&rsk7203_sw1_key_node,
+	&rsk7203_sw2_key_node,
+	&rsk7203_sw3_key_node,
+	NULL
+};
+
+static const struct platform_device_info rsk7203_devices[] __initconst = {
+	{
+		.name		= "smsc911x",
+		.id		= PLATFORM_DEVID_NONE,
+		.res		= smsc911x_resources,
+		.num_res	= ARRAY_SIZE(smsc911x_resources),
+		.data		= &smsc911x_config,
+		.size_data	= sizeof(smsc911x_config),
+	},
+	{
+		.name		= "leds-gpio",
+		.id		= PLATFORM_DEVID_NONE,
+		.swnode		= &rsk7203_gpio_leds_node,
+	},
+	{
+		.name		= "gpio-keys-polled",
+		.id		= PLATFORM_DEVID_NONE,
+		.swnode		= &rsk7203_gpio_keys_node,
+	},
 };
 
 static int __init rsk7203_devices_setup(void)
 {
+	struct platform_device *pd;
+	int error;
+	int i;
+
 	/* Select pins for SCIF0 */
 	gpio_request(GPIO_FN_TXD0, NULL);
 	gpio_request(GPIO_FN_RXD0, NULL);
@@ -131,7 +179,22 @@ static int __init rsk7203_devices_setup(void)
 	__raw_writel(0x36db0400, 0xfffc0008); /* CS1BCR */
 	gpio_request(GPIO_FN_IRQ0_PB, NULL);
 
-	return platform_add_devices(rsk7203_devices,
-				    ARRAY_SIZE(rsk7203_devices));
+	error = software_node_register_node_group(rsk7203_swnodes);
+	if (error) {
+		pr_err("failed to register software nodes: %d\n", error);
+		return error;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {
+		pd = platform_device_register_full(&rsk7203_devices[i]);
+		error = PTR_ERR_OR_ZERO(pd);
+		if (error) {
+			pr_err("failed to create platform device %s: %d\n",
+			       rsk7203_devices[i].name, error);
+			return error;
+		}
+	}
+
+	return 0;
 }
 device_initcall(rsk7203_devices_setup);

-- 
2.54.0.669.g59709faab0-goog

Re: [PATCH v2 3/5] sh: mach-rsk: rsk7203: use static device properties for LEDs and GPIO buttons

[Bartosz Golaszewski]

On Thu, 21 May 2026 07:13:19 +0200, Dmitry Torokhov
<dmitry.torokhov@gmail.com> said:
> Convert the board to use static device properties instead of platform
> data to describe LEDs and GPIO-connected buttons on the board, so
> that support for platform data can be removed from gpio-keys and other
> drivers, unifying their behavior.
>
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> ---

Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Re: [PATCH v2 3/5] sh: mach-rsk: rsk7203: use static device properties for LEDs and GPIO buttons

[Andy Shevchenko]

On Wed, May 20, 2026 at 10:13:19PM -0700, Dmitry Torokhov wrote:
> Convert the board to use static device properties instead of platform
> data to describe LEDs and GPIO-connected buttons on the board, so
> that support for platform data can be removed from gpio-keys and other
> drivers, unifying their behavior.

...

> +	for (i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {

	for (unsigned int i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {

...and drop the above definition of i.

> +		pd = platform_device_register_full(&rsk7203_devices[i]);
> +		error = PTR_ERR_OR_ZERO(pd);
> +		if (error) {
> +			pr_err("failed to create platform device %s: %d\n",
> +			       rsk7203_devices[i].name, error);
> +			return error;
> +		}
> +	}

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2 3/5] sh: mach-rsk: rsk7203: use static device properties for LEDs and GPIO buttons

[Dmitry Torokhov]

On Wed, Jun 03, 2026 at 01:02:56AM +0300, Andy Shevchenko wrote:
> On Wed, May 20, 2026 at 10:13:19PM -0700, Dmitry Torokhov wrote:
> > Convert the board to use static device properties instead of platform
> > data to describe LEDs and GPIO-connected buttons on the board, so
> > that support for platform data can be removed from gpio-keys and other
> > drivers, unifying their behavior.
> 
> ...
> 
> > +	for (i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {
> 
> 	for (unsigned int i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {
> 
> ...and drop the above definition of i.

Why? I do not see coding style suggesting this. 

-- 
Dmitry

Re: [PATCH v2 3/5] sh: mach-rsk: rsk7203: use static device properties for LEDs and GPIO buttons

[Andy Shevchenko]

On Tue, Jun 02, 2026 at 03:06:14PM -0700, Dmitry Torokhov wrote:
> On Wed, Jun 03, 2026 at 01:02:56AM +0300, Andy Shevchenko wrote:
> > On Wed, May 20, 2026 at 10:13:19PM -0700, Dmitry Torokhov wrote:

...

> > > +	for (i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {
> > 
> > 	for (unsigned int i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {
> > 
> > ...and drop the above definition of i.
> 
> Why? I do not see coding style suggesting this. 

Linus Torvalds.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2 3/5] sh: mach-rsk: rsk7203: use static device properties for LEDs and GPIO buttons

[Andy Shevchenko]

On Wed, Jun 03, 2026 at 02:45:39AM +0300, Andy Shevchenko wrote:
> On Tue, Jun 02, 2026 at 03:06:14PM -0700, Dmitry Torokhov wrote:
> > On Wed, Jun 03, 2026 at 01:02:56AM +0300, Andy Shevchenko wrote:
> > > On Wed, May 20, 2026 at 10:13:19PM -0700, Dmitry Torokhov wrote:

...

> > > > +	for (i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {
> > > 
> > > 	for (unsigned int i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {
> > > 
> > > ...and drop the above definition of i.
> > 
> > Why? I do not see coding style suggesting this. 
> 
> Linus Torvalds.

https://lore.kernel.org/lkml/CAHk-=wgy8p4is8ApEQCT5NS7XFb+NXeo-TKz7jRRZVksLLBSrQ@mail.gmail.com/

And IIRC it was another discussion (more recent than that) where he again
mentioned nice of use for-loops with local iterators.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2 3/5] sh: mach-rsk: rsk7203: use static device properties for LEDs and GPIO buttons

[Dmitry Torokhov]

On Wed, Jun 03, 2026 at 02:45:34AM +0300, Andy Shevchenko wrote:
> On Tue, Jun 02, 2026 at 03:06:14PM -0700, Dmitry Torokhov wrote:
> > On Wed, Jun 03, 2026 at 01:02:56AM +0300, Andy Shevchenko wrote:
> > > On Wed, May 20, 2026 at 10:13:19PM -0700, Dmitry Torokhov wrote:
> 
> ...
> 
> > > > +	for (i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {
> > > 
> > > 	for (unsigned int i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {
> > > 
> > > ...and drop the above definition of i.
> > 
> > Why? I do not see coding style suggesting this. 
> 
> Linus Torvalds.

Context matters.

If you want this to be a universal requirement work on adding this to
coding style and to checkpatch. Otherwise declaring loop iterator inside
the loop can be beneficial but in many cases it does not really matter
and can be left to the code author and the revealing style for the
affected code area.

Thanks.

-- 
Dmitry

Re: [PATCH v2 3/5] sh: mach-rsk: rsk7203: use static device properties for LEDs and GPIO buttons

[Andy Shevchenko]

On Tue, Jun 02, 2026 at 04:52:37PM -0700, Dmitry Torokhov wrote:
> On Wed, Jun 03, 2026 at 02:45:34AM +0300, Andy Shevchenko wrote:
> > On Tue, Jun 02, 2026 at 03:06:14PM -0700, Dmitry Torokhov wrote:
> > > On Wed, Jun 03, 2026 at 01:02:56AM +0300, Andy Shevchenko wrote:
> > > > On Wed, May 20, 2026 at 10:13:19PM -0700, Dmitry Torokhov wrote:

...

> > > > > +	for (i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {
> > > > 
> > > > 	for (unsigned int i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {
> > > > 
> > > > ...and drop the above definition of i.
> > > 
> > > Why? I do not see coding style suggesting this. 
> > 
> > Linus Torvalds.
> 
> Context matters.
> 
> If you want this to be a universal requirement work on adding this to
> coding style and to checkpatch. Otherwise declaring loop iterator inside
> the loop can be beneficial but in many cases it does not really matter
> and can be left to the code author and the revealing style for the
> affected code area.

From the common sense perspective this makes code shorter and isolated, which
is a good thing as it makes it robust against wrong re-use of the iterator
variable.

Anyway, I replied already with a link.

-- 
With Best Regards,
Andy Shevchenko

[PATCH v2 4/5] pinctrl: renesas: gpio: support software nodes for function GPIOs

[Dmitry Torokhov]

This patch extends the sh-pfc GPIO driver to support software-node-based
configuration for the secondary 'function' GPIO chip.

While the primary GPIO chip typically uses the firmware node attached to
the parent platform device, the secondary chip should target a specific
child node to avoid ambiguity when defining GPIO hogs or properties.

Update gpio_function_setup() to look for a child node named 'functions',
but only when the parent is a software node. This ensures the behavior
is restricted to legacy platforms being migrated to software nodes.

Assisted-by: Gemini:gemini-3.1-pro
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/pinctrl/renesas/gpio.c | 28 +++++++++++++++++++++++++---
 1 file changed, 25 insertions(+), 3 deletions(-)

diff --git a/drivers/pinctrl/renesas/gpio.c b/drivers/pinctrl/renesas/gpio.c
index 4e59dadb7364..b49a3e14da91 100644
--- a/drivers/pinctrl/renesas/gpio.c
+++ b/drivers/pinctrl/renesas/gpio.c
@@ -271,18 +271,40 @@ static int gpio_function_request(struct gpio_chip *gc, unsigned offset)
 	return ret;
 }
 
+static void sh_pfc_fwnode_put(void *data)
+{
+	fwnode_handle_put(data);
+}
+
 static int gpio_function_setup(struct sh_pfc_chip *chip)
 {
 	struct sh_pfc *pfc = chip->pfc;
 	struct gpio_chip *gc = &chip->gpio_chip;
+	struct fwnode_handle *fwnode = dev_fwnode(pfc->dev);
 
 	gc->request = gpio_function_request;
 
+	if (is_software_node(fwnode)) {
+		fwnode = fwnode_get_named_child_node(fwnode, "functions");
+		if (fwnode) {
+			int ret;
+
+			ret = devm_add_action_or_reset(pfc->dev,
+						       sh_pfc_fwnode_put,
+						       fwnode);
+			if (ret)
+				return ret;
+
+			gc->fwnode = fwnode;
+		}
+	}
+
 	/*
-	 * Explicitly mask the parent's fwnode to prevent gpiolib from
-	 * reusing it for function GPIOs.
+	 * If we did not find 'functions' node, explicitly mask the parent's
+	 * fwnode to prevent gpiolib from reusing it for function GPIOs.
 	 */
-	gc->fwnode = ERR_PTR(-ENODEV);
+	if (!gc->fwnode)
+		gc->fwnode = ERR_PTR(-ENODEV);
 
 	gc->label = pfc->info->name;
 	gc->owner = THIS_MODULE;

-- 
2.54.0.669.g59709faab0-goog

Re: [PATCH v2 4/5] pinctrl: renesas: gpio: support software nodes for function GPIOs

[Bartosz Golaszewski]

On Thu, 21 May 2026 07:13:20 +0200, Dmitry Torokhov
<dmitry.torokhov@gmail.com> said:
> This patch extends the sh-pfc GPIO driver to support software-node-based
> configuration for the secondary 'function' GPIO chip.
>
> While the primary GPIO chip typically uses the firmware node attached to
> the parent platform device, the secondary chip should target a specific
> child node to avoid ambiguity when defining GPIO hogs or properties.
>
> Update gpio_function_setup() to look for a child node named 'functions',
> but only when the parent is a software node. This ensures the behavior
> is restricted to legacy platforms being migrated to software nodes.
>
> Assisted-by: Gemini:gemini-3.1-pro
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> ---

Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

[PATCH v2 5/5] sh: mach-rsk: rsk7203: convert pin configuration to using software nodes

[Dmitry Torokhov]

Replace legacy gpio_request() calls used to configure function pins
(SCIF0 TXD/RXD and LAN9118 IRQ) with software nodes describing GPIO
hogs. These hogs are attached to the PFC gpiochip node, allowing the
GPIO subsystem to automatically configure these pins when the driver is
registered.

Assisted-by: Gemini:gemini-3.1-pro
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 arch/sh/boards/mach-rsk/devices-rsk7203.c | 97 +++++++++++++++++++++++++++----
 1 file changed, 85 insertions(+), 12 deletions(-)

diff --git a/arch/sh/boards/mach-rsk/devices-rsk7203.c b/arch/sh/boards/mach-rsk/devices-rsk7203.c
index f8760a91e2f1..e8a8fc1d2ca9 100644
--- a/arch/sh/boards/mach-rsk/devices-rsk7203.c
+++ b/arch/sh/boards/mach-rsk/devices-rsk7203.c
@@ -12,7 +12,6 @@
 #include <linux/smsc911x.h>
 #include <linux/input.h>
 #include <linux/io.h>
-#include <linux/gpio.h>
 #include <linux/gpio/machine.h>
 #include <linux/gpio/property.h>
 #include <asm/machvec.h>
@@ -131,6 +130,56 @@ static const struct software_node rsk7203_sw3_key_node = {
 	},
 };
 
+/* The base of the function GPIOs in the flat enum */
+#define SH7203_FN_BASE GPIO_FN_PINT7_PB
+
+static const struct software_node rsk7203_pfc_functions_node = {
+	.name = "functions",
+	.parent = &pfc_gpiochip_node,
+};
+
+static const struct software_node rsk7203_txd0_hog_node = {
+	.name = "txd0-hog",
+	.parent = &rsk7203_pfc_functions_node,
+	.properties = (const struct property_entry[]) {
+		PROPERTY_ENTRY_BOOL("gpio-hog"),
+		PROPERTY_ENTRY_U32_ARRAY("gpios", ((u32[]){
+			GPIO_FN_TXD0 - SH7203_FN_BASE, GPIO_ACTIVE_HIGH
+		})),
+		PROPERTY_ENTRY_BOOL("input"),
+		PROPERTY_ENTRY_STRING("line-name", "TXD0"),
+		{ }
+	},
+};
+
+static const struct software_node rsk7203_rxd0_hog_node = {
+	.name = "rxd0-hog",
+	.parent = &rsk7203_pfc_functions_node,
+	.properties = (const struct property_entry[]) {
+		PROPERTY_ENTRY_BOOL("gpio-hog"),
+		PROPERTY_ENTRY_U32_ARRAY("gpios", ((u32[]){
+			GPIO_FN_RXD0 - SH7203_FN_BASE, GPIO_ACTIVE_HIGH
+		})),
+		PROPERTY_ENTRY_BOOL("input"),
+		PROPERTY_ENTRY_STRING("line-name", "RXD0"),
+		{ }
+	},
+};
+
+static const struct software_node rsk7203_irq0_hog_node = {
+	.name = "irq0-hog",
+	.parent = &rsk7203_pfc_functions_node,
+	.properties = (const struct property_entry[]) {
+		PROPERTY_ENTRY_BOOL("gpio-hog"),
+		PROPERTY_ENTRY_U32_ARRAY("gpios", ((u32[]){
+			GPIO_FN_IRQ0_PB - SH7203_FN_BASE, GPIO_ACTIVE_HIGH
+		})),
+		PROPERTY_ENTRY_BOOL("input"),
+		PROPERTY_ENTRY_STRING("line-name", "IRQ0_PB"),
+		{ }
+	},
+};
+
 static const struct software_node * const rsk7203_swnodes[] __initconst = {
 	&rsk7203_gpio_leds_node,
 	&rsk7203_green_led_node,
@@ -141,6 +190,10 @@ static const struct software_node * const rsk7203_swnodes[] __initconst = {
 	&rsk7203_sw1_key_node,
 	&rsk7203_sw2_key_node,
 	&rsk7203_sw3_key_node,
+	&rsk7203_pfc_functions_node,
+	&rsk7203_txd0_hog_node,
+	&rsk7203_rxd0_hog_node,
+	&rsk7203_irq0_hog_node,
 	NULL
 };
 
@@ -165,26 +218,46 @@ static const struct platform_device_info rsk7203_devices[] __initconst = {
 	},
 };
 
-static int __init rsk7203_devices_setup(void)
+/*
+ * The pfc-sh7203 device is registered at arch_initcall level, and the
+ * sh-pfc driver (registered at postcore_initcall level) probes as soon
+ * as the device is created.
+ *
+ * We need to register our software nodes at postcore_initcall level so
+ * they are already present in the system when the driver probes and
+ * tries to apply GPIO hogs.
+ */
+static int __init rsk7203_sw_nodes_setup(void)
 {
-	struct platform_device *pd;
 	int error;
-	int i;
 
-	/* Select pins for SCIF0 */
-	gpio_request(GPIO_FN_TXD0, NULL);
-	gpio_request(GPIO_FN_RXD0, NULL);
-
-	/* Setup LAN9118: CS1 in 16-bit Big Endian Mode, IRQ0 at Port B */
-	__raw_writel(0x36db0400, 0xfffc0008); /* CS1BCR */
-	gpio_request(GPIO_FN_IRQ0_PB, NULL);
+	error = software_node_register(&pfc_gpiochip_node);
+	if (error && error != -EEXIST) {
+		pr_err("RSK7203: failed to register PFC software node: %d\n",
+		       error);
+		return error;
+	}
 
 	error = software_node_register_node_group(rsk7203_swnodes);
 	if (error) {
-		pr_err("failed to register software nodes: %d\n", error);
+		pr_err("RSK7203: failed to register board software nodes: %d\n",
+		       error);
 		return error;
 	}
 
+	return 0;
+}
+postcore_initcall(rsk7203_sw_nodes_setup);
+
+static int __init rsk7203_devices_setup(void)
+{
+	struct platform_device *pd;
+	int error;
+	int i;
+
+	/* Setup LAN9118: CS1 in 16-bit Big Endian Mode, IRQ0 at Port B */
+	__raw_writel(0x36db0400, 0xfffc0008); /* CS1BCR */
+
 	for (i = 0; i < ARRAY_SIZE(rsk7203_devices); i++) {
 		pd = platform_device_register_full(&rsk7203_devices[i]);
 		error = PTR_ERR_OR_ZERO(pd);

-- 
2.54.0.669.g59709faab0-goog

Re: [PATCH v2 5/5] sh: mach-rsk: rsk7203: convert pin configuration to using software nodes

[Bartosz Golaszewski]

On Thu, 21 May 2026 07:13:21 +0200, Dmitry Torokhov
<dmitry.torokhov@gmail.com> said:
> Replace legacy gpio_request() calls used to configure function pins
> (SCIF0 TXD/RXD and LAN9118 IRQ) with software nodes describing GPIO
> hogs. These hogs are attached to the PFC gpiochip node, allowing the
> GPIO subsystem to automatically configure these pins when the driver is
> registered.
>
> Assisted-by: Gemini:gemini-3.1-pro
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> ---

Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

Re: [PATCH v2 0/5] rsk7203: switch to using static device property, drop legacy gpio API

[Linus Walleij]

On Thu, May 21, 2026 at 7:13 AM Dmitry Torokhov
<dmitry.torokhov@gmail.com> wrote:

> This series of patches converts rsk7203 to use static device properties
> for its devices, including gpio-keys and gpio-leds, and removing
> dependency on legacy gpio API (in favor of gpiod API).

The series:
Reviewed-by: Linus Walleij <linusw@kernel.org>

Yours,
Linus Walleij