The RP1 is an MFD supporting a gpio controller and /pinmux/pinctrl.
Add minimum support for the gpio only portion. The driver is in
pinctrl folder since upcoming patches will add the pinmux/pinctrl
support where the gpio part can be seen as an addition.

Signed-off-by: Andrea della Porta <andrea.porta@suse.com>
---
Please note that checkpatch warning on this patch are unavoidable.

 MAINTAINERS                   |   1 +
 drivers/pinctrl/Kconfig       |  11 +
 drivers/pinctrl/Makefile      |   1 +
 drivers/pinctrl/pinctrl-rp1.c | 860 ++++++++++++++++++++++++++++++++++
 4 files changed, 873 insertions(+)
 create mode 100644 drivers/pinctrl/pinctrl-rp1.c

diff --git a/MAINTAINERS b/MAINTAINERS
index dc064cd4b6b5..06277969a522 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -19388,6 +19388,7 @@ F:	Documentation/devicetree/bindings/misc/pci1de4,1.yaml
 F:	Documentation/devicetree/bindings/pci/pci-ep-bus.yaml
 F:	Documentation/devicetree/bindings/pinctrl/raspberrypi,rp1-gpio.yaml
 F:	drivers/clk/clk-rp1.c
+F:	drivers/pinctrl/pinctrl-rp1.c
 F:	include/dt-bindings/clock/rp1.h
 F:	include/dt-bindings/misc/rp1.h
 
diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index 354536de564b..f49b8b7f6afa 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -587,6 +587,17 @@ config PINCTRL_MLXBF3
 	  each pin. This driver can also be built as a module called
 	  pinctrl-mlxbf3.
 
+config PINCTRL_RP1
+	bool "Pinctrl driver for RP1"
+	select PINMUX
+	select PINCONF
+	select GENERIC_PINCONF
+	select GPIOLIB
+	select GPIOLIB_IRQCHIP
+	help
+	  Enable the gpio and pinctrl/mux driver for RaspberryPi RP1
+	  multi function device.
+
 source "drivers/pinctrl/actions/Kconfig"
 source "drivers/pinctrl/aspeed/Kconfig"
 source "drivers/pinctrl/bcm/Kconfig"
diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
index 97823f52b972..2d714047a1ce 100644
--- a/drivers/pinctrl/Makefile
+++ b/drivers/pinctrl/Makefile
@@ -47,6 +47,7 @@ obj-$(CONFIG_PINCTRL_PIC32)	+= pinctrl-pic32.o
 obj-$(CONFIG_PINCTRL_PISTACHIO)	+= pinctrl-pistachio.o
 obj-$(CONFIG_PINCTRL_RK805)	+= pinctrl-rk805.o
 obj-$(CONFIG_PINCTRL_ROCKCHIP)	+= pinctrl-rockchip.o
+obj-$(CONFIG_PINCTRL_RP1)       += pinctrl-rp1.o
 obj-$(CONFIG_PINCTRL_SCMI)	+= pinctrl-scmi.o
 obj-$(CONFIG_PINCTRL_SINGLE)	+= pinctrl-single.o
 obj-$(CONFIG_PINCTRL_ST) 	+= pinctrl-st.o
diff --git a/drivers/pinctrl/pinctrl-rp1.c b/drivers/pinctrl/pinctrl-rp1.c
new file mode 100644
index 000000000000..617804871e03
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-rp1.c
@@ -0,0 +1,860 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for Raspberry Pi RP1 GPIO unit
+ *
+ * Copyright (C) 2023 Raspberry Pi Ltd.
+ *
+ * This driver is inspired by:
+ * pinctrl-bcm2835.c, please see original file for copyright information
+ */
+
+#include <linux/gpio/driver.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/configfs.h>
+#include <linux/regmap.h>
+
+#define MODULE_NAME "pinctrl-rp1"
+#define RP1_NUM_GPIOS	54
+#define RP1_NUM_BANKS	3
+
+#define RP1_INT_EDGE_FALLING		BIT(0)
+#define RP1_INT_EDGE_RISING		BIT(1)
+#define RP1_INT_LEVEL_LOW		BIT(2)
+#define RP1_INT_LEVEL_HIGH		BIT(3)
+#define RP1_INT_MASK			GENMASK(3, 0)
+#define RP1_INT_EDGE_BOTH		(RP1_INT_EDGE_FALLING |	\
+					 RP1_INT_EDGE_RISING)
+
+#define RP1_FSEL_COUNT			9
+
+#define RP1_FSEL_ALT0			0x00
+#define RP1_FSEL_GPIO			0x05
+#define RP1_FSEL_NONE			0x09
+#define RP1_FSEL_NONE_HW		0x1f
+
+#define RP1_PAD_DRIVE_2MA		0x0
+#define RP1_PAD_DRIVE_4MA		0x1
+#define RP1_PAD_DRIVE_8MA		0x2
+#define RP1_PAD_DRIVE_12MA		0x3
+
+enum {
+	RP1_PUD_OFF			= 0,
+	RP1_PUD_DOWN			= 1,
+	RP1_PUD_UP			= 2,
+};
+
+enum {
+	RP1_DIR_OUTPUT			= 0,
+	RP1_DIR_INPUT			= 1,
+};
+
+enum {
+	RP1_OUTOVER_PERI		= 0,
+	RP1_OUTOVER_INVPERI		= 1,
+	RP1_OUTOVER_LOW			= 2,
+	RP1_OUTOVER_HIGH		= 3,
+};
+
+enum {
+	RP1_OEOVER_PERI			= 0,
+	RP1_OEOVER_INVPERI		= 1,
+	RP1_OEOVER_DISABLE		= 2,
+	RP1_OEOVER_ENABLE		= 3,
+};
+
+enum {
+	RP1_INOVER_PERI			= 0,
+	RP1_INOVER_INVPERI		= 1,
+	RP1_INOVER_LOW			= 2,
+	RP1_INOVER_HIGH			= 3,
+};
+
+enum {
+	RP1_GPIO_CTRL_IRQRESET_SET		= 0,
+	RP1_GPIO_CTRL_INT_CLR			= 1,
+	RP1_GPIO_CTRL_INT_SET			= 2,
+	RP1_GPIO_CTRL_OEOVER			= 3,
+	RP1_GPIO_CTRL_FUNCSEL			= 4,
+	RP1_GPIO_CTRL_OUTOVER			= 5,
+	RP1_GPIO_CTRL				= 6,
+};
+
+enum {
+	RP1_INTE_SET			= 0,
+	RP1_INTE_CLR			= 1,
+};
+
+enum {
+	RP1_RIO_OUT_SET			= 0,
+	RP1_RIO_OUT_CLR			= 1,
+	RP1_RIO_OE			= 2,
+	RP1_RIO_OE_SET			= 3,
+	RP1_RIO_OE_CLR			= 4,
+	RP1_RIO_IN			= 5,
+};
+
+enum {
+	RP1_PAD_SLEWFAST		= 0,
+	RP1_PAD_SCHMITT			= 1,
+	RP1_PAD_PULL			= 2,
+	RP1_PAD_DRIVE			= 3,
+	RP1_PAD_IN_ENABLE		= 4,
+	RP1_PAD_OUT_DISABLE		= 5,
+};
+
+static const struct reg_field rp1_gpio_fields[] = {
+	[RP1_GPIO_CTRL_IRQRESET_SET]	= REG_FIELD(0x2004, 28, 28),
+	[RP1_GPIO_CTRL_INT_CLR]		= REG_FIELD(0x3004, 20, 23),
+	[RP1_GPIO_CTRL_INT_SET]		= REG_FIELD(0x2004, 20, 23),
+	[RP1_GPIO_CTRL_OEOVER]		= REG_FIELD(0x0004, 14, 15),
+	[RP1_GPIO_CTRL_FUNCSEL]		= REG_FIELD(0x0004, 0, 4),
+	[RP1_GPIO_CTRL_OUTOVER]		= REG_FIELD(0x0004, 12, 13),
+	[RP1_GPIO_CTRL]			= REG_FIELD(0x0004, 0, 31),
+};
+
+static const struct reg_field rp1_inte_fields[] = {
+	[RP1_INTE_SET]			= REG_FIELD(0x2000, 0, 0),
+	[RP1_INTE_CLR]			= REG_FIELD(0x3000, 0, 0),
+};
+
+static const struct reg_field rp1_rio_fields[] = {
+	[RP1_RIO_OUT_SET]		= REG_FIELD(0x2000, 0, 0),
+	[RP1_RIO_OUT_CLR]		= REG_FIELD(0x3000, 0, 0),
+	[RP1_RIO_OE]			= REG_FIELD(0x0004, 0, 0),
+	[RP1_RIO_OE_SET]		= REG_FIELD(0x2004, 0, 0),
+	[RP1_RIO_OE_CLR]		= REG_FIELD(0x3004, 0, 0),
+	[RP1_RIO_IN]			= REG_FIELD(0x0008, 0, 0),
+};
+
+static const struct reg_field rp1_pad_fields[] = {
+	[RP1_PAD_SLEWFAST]		= REG_FIELD(0, 0, 0),
+	[RP1_PAD_SCHMITT]		= REG_FIELD(0, 1, 1),
+	[RP1_PAD_PULL]			= REG_FIELD(0, 2, 3),
+	[RP1_PAD_DRIVE]			= REG_FIELD(0, 4, 5),
+	[RP1_PAD_IN_ENABLE]		= REG_FIELD(0, 6, 6),
+	[RP1_PAD_OUT_DISABLE]		= REG_FIELD(0, 7, 7),
+};
+
+struct rp1_iobank_desc {
+	int min_gpio;
+	int num_gpios;
+	int gpio_offset;
+	int inte_offset;
+	int ints_offset;
+	int rio_offset;
+	int pads_offset;
+};
+
+struct rp1_pin_info {
+	u8 num;
+	u8 bank;
+	u8 offset;
+	u8 fsel;
+	u8 irq_type;
+
+	struct regmap_field *gpio[ARRAY_SIZE(rp1_gpio_fields)];
+	struct regmap_field *rio[ARRAY_SIZE(rp1_rio_fields)];
+	struct regmap_field *inte[ARRAY_SIZE(rp1_inte_fields)];
+	struct regmap_field *pad[ARRAY_SIZE(rp1_pad_fields)];
+};
+
+struct rp1_pinctrl {
+	struct device *dev;
+	void __iomem *gpio_base;
+	void __iomem *rio_base;
+	void __iomem *pads_base;
+	int irq[RP1_NUM_BANKS];
+	struct rp1_pin_info pins[RP1_NUM_GPIOS];
+
+	struct pinctrl_dev *pctl_dev;
+	struct gpio_chip gpio_chip;
+	struct pinctrl_gpio_range gpio_range;
+
+	raw_spinlock_t irq_lock[RP1_NUM_BANKS];
+
+	struct configfs_subsystem subsys;
+};
+
+static const struct rp1_iobank_desc rp1_iobanks[RP1_NUM_BANKS] = {
+	/*         gpio   inte    ints     rio    pads */
+	{  0, 28, 0x0000, 0x011c, 0x0124, 0x0000, 0x0004 },
+	{ 28,  6, 0x4000, 0x411c, 0x4124, 0x4000, 0x4004 },
+	{ 34, 20, 0x8000, 0x811c, 0x8124, 0x8000, 0x8004 },
+};
+
+static int rp1_pinconf_set(struct rp1_pin_info *pin,
+			   unsigned int offset, unsigned long *configs,
+			   unsigned int num_configs);
+
+static struct rp1_pin_info *rp1_get_pin(struct gpio_chip *chip,
+					unsigned int offset)
+{
+	struct rp1_pinctrl *pc = gpiochip_get_data(chip);
+
+	if (pc && offset < RP1_NUM_GPIOS)
+		return &pc->pins[offset];
+	return NULL;
+}
+
+static void rp1_input_enable(struct rp1_pin_info *pin, int value)
+{
+	regmap_field_write(pin->pad[RP1_PAD_IN_ENABLE], !!value);
+}
+
+static void rp1_output_enable(struct rp1_pin_info *pin, int value)
+{
+	regmap_field_write(pin->pad[RP1_PAD_OUT_DISABLE], !value);
+}
+
+static u32 rp1_get_fsel(struct rp1_pin_info *pin)
+{
+	u32 oeover, fsel;
+
+	regmap_field_read(pin->gpio[RP1_GPIO_CTRL_OEOVER], &oeover);
+	regmap_field_read(pin->gpio[RP1_GPIO_CTRL_FUNCSEL], &fsel);
+
+	if (oeover != RP1_OEOVER_PERI || fsel >= RP1_FSEL_COUNT)
+		fsel = RP1_FSEL_NONE;
+
+	return fsel;
+}
+
+static void rp1_set_fsel(struct rp1_pin_info *pin, u32 fsel)
+{
+	if (fsel >= RP1_FSEL_COUNT)
+		fsel = RP1_FSEL_NONE_HW;
+
+	rp1_input_enable(pin, 1);
+	rp1_output_enable(pin, 1);
+
+	if (fsel == RP1_FSEL_NONE) {
+		regmap_field_write(pin->gpio[RP1_GPIO_CTRL_OEOVER], RP1_OEOVER_DISABLE);
+	} else {
+		regmap_field_write(pin->gpio[RP1_GPIO_CTRL_OUTOVER], RP1_OUTOVER_PERI);
+		regmap_field_write(pin->gpio[RP1_GPIO_CTRL_OEOVER], RP1_OEOVER_PERI);
+	}
+
+	regmap_field_write(pin->gpio[RP1_GPIO_CTRL_FUNCSEL], fsel);
+}
+
+static int rp1_get_dir(struct rp1_pin_info *pin)
+{
+	unsigned int val;
+
+	regmap_field_read(pin->rio[RP1_RIO_OE], &val);
+
+	return !val ? RP1_DIR_INPUT : RP1_DIR_OUTPUT;
+}
+
+static void rp1_set_dir(struct rp1_pin_info *pin, bool is_input)
+{
+	int reg = is_input ? RP1_RIO_OE_CLR : RP1_RIO_OE_SET;
+
+	regmap_field_write(pin->rio[reg], 1);
+}
+
+static int rp1_get_value(struct rp1_pin_info *pin)
+{
+	unsigned int val;
+
+	regmap_field_read(pin->rio[RP1_RIO_IN], &val);
+
+	return !!val;
+}
+
+static void rp1_set_value(struct rp1_pin_info *pin, int value)
+{
+	/* Assume the pin is already an output */
+	int reg = value ? RP1_RIO_OUT_SET : RP1_RIO_OUT_CLR;
+
+	regmap_field_write(pin->rio[reg], 1);
+}
+
+static int rp1_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+	struct rp1_pin_info *pin = rp1_get_pin(chip, offset);
+	int ret;
+
+	if (!pin)
+		return -EINVAL;
+
+	ret = rp1_get_value(pin);
+
+	return ret;
+}
+
+static void rp1_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
+{
+	struct rp1_pin_info *pin = rp1_get_pin(chip, offset);
+
+	if (pin)
+		rp1_set_value(pin, value);
+}
+
+static int rp1_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
+{
+	struct rp1_pin_info *pin = rp1_get_pin(chip, offset);
+	u32 fsel;
+
+	if (!pin)
+		return -EINVAL;
+
+	fsel = rp1_get_fsel(pin);
+	if (fsel != RP1_FSEL_GPIO)
+		return -EINVAL;
+
+	return (rp1_get_dir(pin) == RP1_DIR_OUTPUT) ?
+		GPIO_LINE_DIRECTION_OUT :
+		GPIO_LINE_DIRECTION_IN;
+}
+
+static int rp1_gpio_direction_input(struct gpio_chip *chip, unsigned int offset)
+{
+	struct rp1_pin_info *pin = rp1_get_pin(chip, offset);
+
+	if (!pin)
+		return -EINVAL;
+	rp1_set_dir(pin, RP1_DIR_INPUT);
+	rp1_set_fsel(pin, RP1_FSEL_GPIO);
+
+	return 0;
+}
+
+static int rp1_gpio_direction_output(struct gpio_chip *chip, unsigned int offset,
+				     int value)
+{
+	struct rp1_pin_info *pin = rp1_get_pin(chip, offset);
+
+	if (!pin)
+		return -EINVAL;
+	rp1_set_value(pin, value);
+	rp1_set_dir(pin, RP1_DIR_OUTPUT);
+	rp1_set_fsel(pin, RP1_FSEL_GPIO);
+
+	return 0;
+}
+
+static int rp1_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
+			       unsigned long config)
+{
+	struct rp1_pin_info *pin = rp1_get_pin(chip, offset);
+	unsigned long configs[] = { config };
+
+	return rp1_pinconf_set(pin, offset, configs,
+			       ARRAY_SIZE(configs));
+}
+
+static const struct gpio_chip rp1_gpio_chip = {
+	.label = MODULE_NAME,
+	.owner = THIS_MODULE,
+	.request = gpiochip_generic_request,
+	.free = gpiochip_generic_free,
+	.direction_input = rp1_gpio_direction_input,
+	.direction_output = rp1_gpio_direction_output,
+	.get_direction = rp1_gpio_get_direction,
+	.get = rp1_gpio_get,
+	.set = rp1_gpio_set,
+	.base = -1,
+	.set_config = rp1_gpio_set_config,
+	.ngpio = RP1_NUM_GPIOS,
+	.can_sleep = false,
+};
+
+static void rp1_gpio_irq_handler(struct irq_desc *desc)
+{
+	struct gpio_chip *chip = irq_desc_get_handler_data(desc);
+	struct irq_chip *host_chip = irq_desc_get_chip(desc);
+	struct rp1_pinctrl *pc = gpiochip_get_data(chip);
+	const struct rp1_iobank_desc *bank;
+	int irq = irq_desc_get_irq(desc);
+	unsigned long ints;
+	int bit_pos;
+
+	if (pc->irq[0] == irq)
+		bank = &rp1_iobanks[0];
+	else if (pc->irq[1] == irq)
+		bank = &rp1_iobanks[1];
+	else
+		bank = &rp1_iobanks[2];
+
+	chained_irq_enter(host_chip, desc);
+
+	ints = readl(pc->gpio_base + bank->ints_offset);
+	for_each_set_bit(bit_pos, &ints, 32) {
+		struct rp1_pin_info *pin = rp1_get_pin(chip, bit_pos);
+
+		regmap_field_write(pin->gpio[RP1_GPIO_CTRL_IRQRESET_SET], 1);
+		generic_handle_irq(irq_linear_revmap(pc->gpio_chip.irq.domain,
+						     bank->gpio_offset + bit_pos));
+	}
+
+	chained_irq_exit(host_chip, desc);
+}
+
+static void rp1_gpio_irq_config(struct rp1_pin_info *pin, bool enable)
+{
+	int reg = enable ? RP1_INTE_SET : RP1_INTE_CLR;
+
+	regmap_field_write(pin->inte[reg], 1);
+	if (!enable)
+		/* Clear any latched events */
+		regmap_field_write(pin->gpio[RP1_GPIO_CTRL_IRQRESET_SET], 1);
+}
+
+static void rp1_gpio_irq_enable(struct irq_data *data)
+{
+	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+	unsigned int gpio = irqd_to_hwirq(data);
+	struct rp1_pin_info *pin = rp1_get_pin(chip, gpio);
+
+	rp1_gpio_irq_config(pin, true);
+}
+
+static void rp1_gpio_irq_disable(struct irq_data *data)
+{
+	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+	unsigned int gpio = irqd_to_hwirq(data);
+	struct rp1_pin_info *pin = rp1_get_pin(chip, gpio);
+
+	rp1_gpio_irq_config(pin, false);
+}
+
+static int rp1_irq_set_type(struct rp1_pin_info *pin, unsigned int type)
+{
+	u32 irq_flags;
+
+	switch (type) {
+	case IRQ_TYPE_NONE:
+		irq_flags = 0;
+		break;
+	case IRQ_TYPE_EDGE_RISING:
+		irq_flags = RP1_INT_EDGE_RISING;
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		irq_flags = RP1_INT_EDGE_FALLING;
+		break;
+	case IRQ_TYPE_EDGE_BOTH:
+		irq_flags = RP1_INT_EDGE_RISING | RP1_INT_EDGE_FALLING;
+		break;
+	case IRQ_TYPE_LEVEL_HIGH:
+		irq_flags = RP1_INT_LEVEL_HIGH;
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+		irq_flags = RP1_INT_LEVEL_LOW;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	/* Clear them all */
+	regmap_field_write(pin->gpio[RP1_GPIO_CTRL_INT_CLR], RP1_INT_MASK);
+
+	/* Set those that are needed */
+	regmap_field_write(pin->gpio[RP1_GPIO_CTRL_INT_SET], irq_flags);
+	pin->irq_type = type;
+
+	return 0;
+}
+
+static int rp1_gpio_irq_set_type(struct irq_data *data, unsigned int type)
+{
+	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+	unsigned int gpio = irqd_to_hwirq(data);
+	struct rp1_pin_info *pin = rp1_get_pin(chip, gpio);
+	struct rp1_pinctrl *pc = gpiochip_get_data(chip);
+	int bank = pin->bank;
+	unsigned long flags;
+	int ret;
+
+	raw_spin_lock_irqsave(&pc->irq_lock[bank], flags);
+
+	ret = rp1_irq_set_type(pin, type);
+	if (!ret) {
+		if (type & IRQ_TYPE_EDGE_BOTH)
+			irq_set_handler_locked(data, handle_edge_irq);
+		else
+			irq_set_handler_locked(data, handle_level_irq);
+	}
+
+	raw_spin_unlock_irqrestore(&pc->irq_lock[bank], flags);
+
+	return ret;
+}
+
+static void rp1_gpio_irq_ack(struct irq_data *data)
+{
+	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+	unsigned int gpio = irqd_to_hwirq(data);
+	struct rp1_pin_info *pin = rp1_get_pin(chip, gpio);
+
+	/* Clear any latched events */
+	regmap_field_write(pin->gpio[RP1_GPIO_CTRL_IRQRESET_SET], 1);
+}
+
+static struct irq_chip rp1_gpio_irq_chip = {
+	.name = MODULE_NAME,
+	.irq_enable = rp1_gpio_irq_enable,
+	.irq_disable = rp1_gpio_irq_disable,
+	.irq_set_type = rp1_gpio_irq_set_type,
+	.irq_ack = rp1_gpio_irq_ack,
+	.irq_mask = rp1_gpio_irq_disable,
+	.irq_unmask = rp1_gpio_irq_enable,
+	.flags = IRQCHIP_IMMUTABLE,
+};
+
+static void rp1_pull_config_set(struct rp1_pin_info *pin, unsigned int arg)
+{
+	regmap_field_write(pin->pad[RP1_PAD_PULL], arg & 0x3);
+}
+
+static int rp1_pinconf_set(struct rp1_pin_info *pin, unsigned int offset,
+			   unsigned long *configs, unsigned int num_configs)
+{
+	u32 param, arg;
+	int i;
+
+	if (!pin)
+		return -EINVAL;
+
+	for (i = 0; i < num_configs; i++) {
+		param = pinconf_to_config_param(configs[i]);
+		arg = pinconf_to_config_argument(configs[i]);
+
+		switch (param) {
+		case PIN_CONFIG_BIAS_DISABLE:
+			rp1_pull_config_set(pin, RP1_PUD_OFF);
+			break;
+
+		case PIN_CONFIG_BIAS_PULL_DOWN:
+			rp1_pull_config_set(pin, RP1_PUD_DOWN);
+			break;
+
+		case PIN_CONFIG_BIAS_PULL_UP:
+			rp1_pull_config_set(pin, RP1_PUD_UP);
+			break;
+
+		case PIN_CONFIG_INPUT_ENABLE:
+			rp1_input_enable(pin, arg);
+			break;
+
+		case PIN_CONFIG_OUTPUT_ENABLE:
+			rp1_output_enable(pin, arg);
+			break;
+
+		case PIN_CONFIG_OUTPUT:
+			rp1_set_value(pin, arg);
+			rp1_set_dir(pin, RP1_DIR_OUTPUT);
+			rp1_set_fsel(pin, RP1_FSEL_GPIO);
+			break;
+
+		case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
+			regmap_field_write(pin->pad[RP1_PAD_SCHMITT], !!arg);
+			break;
+
+		case PIN_CONFIG_SLEW_RATE:
+			regmap_field_write(pin->pad[RP1_PAD_SLEWFAST], !!arg);
+			break;
+
+		case PIN_CONFIG_DRIVE_STRENGTH:
+			switch (arg) {
+			case 2:
+				arg = RP1_PAD_DRIVE_2MA;
+				break;
+			case 4:
+				arg = RP1_PAD_DRIVE_4MA;
+				break;
+			case 8:
+				arg = RP1_PAD_DRIVE_8MA;
+				break;
+			case 12:
+				arg = RP1_PAD_DRIVE_12MA;
+				break;
+			default:
+				return -ENOTSUPP;
+			}
+			regmap_field_write(pin->pad[RP1_PAD_DRIVE], arg);
+			break;
+
+		default:
+			return -ENOTSUPP;
+
+		} /* switch param type */
+	} /* for each config */
+
+	return 0;
+}
+
+static const struct of_device_id rp1_pinctrl_match[] = {
+	{ .compatible = "raspberrypi,rp1-gpio" },
+	{},
+};
+
+static ssize_t rp1_gpio_set_names_write(struct config_item *item,
+					const void *buf, size_t count)
+{
+	struct rp1_pinctrl *rp1	= container_of(to_configfs_subsystem(to_config_group(item)),
+					       struct rp1_pinctrl, subsys);
+	struct gpio_chip *chip = &rp1->gpio_chip;
+	struct device *dev = rp1->dev;
+	int ret, ovcs_id;
+
+	ret = of_overlay_fdt_apply(buf, count, &ovcs_id, NULL);
+
+	if (ret) {
+		dev_err(dev, "Cannot apply rp1_gpio overlay\n");
+		return ret;
+	}
+
+	ret = gpiochip_set_names(chip);
+
+	if (ret) {
+		dev_err(dev, "Cannot set gpio line names\n");
+		return ret;
+	}
+
+	return count;
+}
+
+CONFIGFS_BIN_ATTR_WO(rp1_, gpio_set_names, NULL, 2048);
+
+static struct configfs_bin_attribute *rp1_cfg_attrs[] = {
+	&rp1_attr_gpio_set_names,
+	NULL,
+};
+
+static const struct config_item_type rp1_cfg_type = {
+	.ct_bin_attrs   = rp1_cfg_attrs,
+	.ct_owner       = THIS_MODULE,
+};
+
+static struct rp1_pinctrl rp1_pinctrl_data = {
+	.subsys = {
+		.su_group = {
+			.cg_item = {
+				.ci_namebuf = "rp1-cfg",
+				.ci_type = &rp1_cfg_type,
+			},
+		},
+	},
+};
+
+static const struct regmap_config rp1_pinctrl_regmap_cfg = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.fast_io = true,
+	.name = "rp1-pinctrl",
+};
+
+static int rp1_gen_regfield(struct device *dev,
+			    const struct reg_field *array,
+			    size_t array_size,
+			    int reg_off,
+			    int pin_off,
+			    bool additive_offset,
+			    struct regmap *regmap,
+			    struct regmap_field *out[])
+{
+	struct reg_field regfield;
+	int k;
+
+	for (k = 0; k < array_size; k++) {
+		regfield = array[k];
+		regfield.reg = (additive_offset ? regfield.reg : 0) + reg_off;
+		if (pin_off >= 0) {
+			regfield.lsb = pin_off;
+			regfield.msb = regfield.lsb;
+		}
+		out[k] = devm_regmap_field_alloc(dev, regmap, regfield);
+
+		if (IS_ERR(out[k]))
+			return PTR_ERR(out[k]);
+	}
+
+	return 0;
+}
+
+static int rp1_pinctrl_probe(struct platform_device *pdev)
+{
+	struct regmap *gpio_regmap, *rio_regmap, *pads_regmap;
+	struct rp1_pinctrl *pc = &rp1_pinctrl_data;
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct gpio_irq_chip *girq;
+	int err, i;
+
+	pc->dev = dev;
+	pc->gpio_chip = rp1_gpio_chip;
+	pc->gpio_chip.parent = dev;
+
+	pc->gpio_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(pc->gpio_base)) {
+		dev_err(dev, "could not get GPIO IO memory\n");
+		return PTR_ERR(pc->gpio_base);
+	}
+
+	pc->rio_base = devm_platform_ioremap_resource(pdev, 1);
+	if (IS_ERR(pc->rio_base)) {
+		dev_err(dev, "could not get RIO IO memory\n");
+		return PTR_ERR(pc->rio_base);
+	}
+
+	pc->pads_base = devm_platform_ioremap_resource(pdev, 2);
+	if (IS_ERR(pc->pads_base)) {
+		dev_err(dev, "could not get PADS IO memory\n");
+		return PTR_ERR(pc->pads_base);
+	}
+
+	gpio_regmap = devm_regmap_init_mmio(dev, pc->gpio_base,
+					    &rp1_pinctrl_regmap_cfg);
+	if (IS_ERR(gpio_regmap)) {
+		dev_err(dev, "could not init GPIO regmap\n");
+		return PTR_ERR(gpio_regmap);
+	}
+
+	rio_regmap = devm_regmap_init_mmio(dev, pc->rio_base,
+					   &rp1_pinctrl_regmap_cfg);
+	if (IS_ERR(rio_regmap)) {
+		dev_err(dev, "could not init RIO regmap\n");
+		return PTR_ERR(rio_regmap);
+	}
+
+	pads_regmap = devm_regmap_init_mmio(dev, pc->pads_base,
+					    &rp1_pinctrl_regmap_cfg);
+	if (IS_ERR(pads_regmap)) {
+		dev_err(dev, "could not init PADS regmap\n");
+		return PTR_ERR(pads_regmap);
+	}
+
+	for (i = 0; i < RP1_NUM_BANKS; i++) {
+		const struct rp1_iobank_desc *bank = &rp1_iobanks[i];
+		int j;
+
+		for (j = 0; j < bank->num_gpios; j++) {
+			struct rp1_pin_info *pin =
+				&pc->pins[bank->min_gpio + j];
+			int reg_off;
+
+			pin->num = bank->min_gpio + j;
+			pin->bank = i;
+			pin->offset = j;
+
+			reg_off = bank->gpio_offset + pin->offset
+				  * sizeof(u32) * 2;
+			err = rp1_gen_regfield(dev,
+					       rp1_gpio_fields,
+					       ARRAY_SIZE(rp1_gpio_fields),
+					       reg_off,
+					       -1,
+					       true,
+					       gpio_regmap,
+					       pin->gpio);
+
+			if (err) {
+				dev_err(dev, "Unable to allocate regmap for gpio\n");
+				return err;
+			}
+
+			reg_off = bank->inte_offset;
+			err = rp1_gen_regfield(dev,
+					       rp1_inte_fields,
+					       ARRAY_SIZE(rp1_inte_fields),
+					       reg_off,
+					       pin->offset,
+					       true,
+					       gpio_regmap,
+					       pin->inte);
+
+			if (err) {
+				dev_err(dev, "Unable to allocate regmap for inte\n");
+				return err;
+			}
+
+			reg_off = bank->rio_offset;
+			err = rp1_gen_regfield(dev,
+					       rp1_rio_fields,
+					       ARRAY_SIZE(rp1_rio_fields),
+					       reg_off,
+					       pin->offset,
+					       true,
+					       rio_regmap,
+					       pin->rio);
+
+			if (err) {
+				dev_err(dev, "Unable to allocate regmap for rio\n");
+				return err;
+			}
+
+			reg_off = bank->pads_offset + pin->offset * sizeof(u32);
+			err = rp1_gen_regfield(dev,
+					       rp1_pad_fields,
+					       ARRAY_SIZE(rp1_pad_fields),
+					       reg_off,
+					       -1,
+					       false,
+					       pads_regmap,
+					       pin->pad);
+
+			if (err) {
+				dev_err(dev, "Unable to allocate regmap for pad\n");
+				return err;
+			}
+		}
+
+		raw_spin_lock_init(&pc->irq_lock[i]);
+	}
+
+	girq = &pc->gpio_chip.irq;
+	girq->chip = &rp1_gpio_irq_chip;
+	girq->parent_handler = rp1_gpio_irq_handler;
+	girq->num_parents = RP1_NUM_BANKS;
+	girq->parents = pc->irq;
+	girq->default_type = IRQ_TYPE_NONE;
+	girq->handler = handle_level_irq;
+
+	/*
+	 * Use the same handler for all groups: this is necessary
+	 * since we use one gpiochip to cover all lines - the
+	 * irq handler then needs to figure out which group and
+	 * bank that was firing the IRQ and look up the per-group
+	 * and bank data.
+	 */
+	for (i = 0; i < RP1_NUM_BANKS; i++) {
+		pc->irq[i] = irq_of_parse_and_map(np, i);
+		if (!pc->irq[i]) {
+			girq->num_parents = i;
+			break;
+		}
+	}
+
+	platform_set_drvdata(pdev, pc);
+
+	err = devm_gpiochip_add_data(dev, &pc->gpio_chip, pc);
+	if (err) {
+		dev_err(dev, "could not add GPIO chip\n");
+		return err;
+	}
+
+	config_group_init(&pc->subsys.su_group);
+	mutex_init(&pc->subsys.su_mutex);
+	err = configfs_register_subsystem(&pc->subsys);
+	if (err) {
+		dev_err(dev, "Error %d while registering subsystem %s\n",
+			err, pc->subsys.su_group.cg_item.ci_namebuf);
+		return err;
+	}
+
+	return 0;
+}
+
+static struct platform_driver rp1_pinctrl_driver = {
+	.probe = rp1_pinctrl_probe,
+	.driver = {
+		.name = MODULE_NAME,
+		.of_match_table = rp1_pinctrl_match,
+		.suppress_bind_attrs = true,
+	},
+};
+builtin_platform_driver(rp1_pinctrl_driver);
-- 
2.35.3

On Mon, Oct 7, 2024 at 2:39 PM Andrea della Porta <andrea.porta@suse.com> wrote:

> The RP1 is an MFD supporting a gpio controller and /pinmux/pinctrl.
> Add minimum support for the gpio only portion. The driver is in
> pinctrl folder since upcoming patches will add the pinmux/pinctrl
> support where the gpio part can be seen as an addition.
>
> Signed-off-by: Andrea della Porta <andrea.porta@suse.com>

This is a nice driver and I find no issues with it, what causes
an issue is gpiochip_set_names() as pointed out by Bartosz.
If you can live without the names you can remove that part for
now and we can merge the driver, then you can add the names
later when we sorted out how to share that function.

Yours,
Linus Walleij

Hi Linux,

On 11:03 Fri 11 Oct     , Linus Walleij wrote:
> On Mon, Oct 7, 2024 at 2:39 PM Andrea della Porta <andrea.porta@suse.com> wrote:
> 
> > The RP1 is an MFD supporting a gpio controller and /pinmux/pinctrl.
> > Add minimum support for the gpio only portion. The driver is in
> > pinctrl folder since upcoming patches will add the pinmux/pinctrl
> > support where the gpio part can be seen as an addition.
> >
> > Signed-off-by: Andrea della Porta <andrea.porta@suse.com>
> 
> This is a nice driver and I find no issues with it, what causes
> an issue is gpiochip_set_names() as pointed out by Bartosz.
> If you can live without the names you can remove that part for
> now and we can merge the driver, then you can add the names
> later when we sorted out how to share that function.

Sure, I'll drop the gpio-line-names patch for now.

Many thanks,
Andrea

> 
> Yours,
> Linus Walleij

Am 11.10.24 um 11:03 schrieb Linus Walleij:
> On Mon, Oct 7, 2024 at 2:39 PM Andrea della Porta <andrea.porta@suse.com> wrote:
>
>> The RP1 is an MFD supporting a gpio controller and /pinmux/pinctrl.
>> Add minimum support for the gpio only portion. The driver is in
>> pinctrl folder since upcoming patches will add the pinmux/pinctrl
>> support where the gpio part can be seen as an addition.
>>
>> Signed-off-by: Andrea della Porta <andrea.porta@suse.com>
> This is a nice driver and I find no issues with it, what causes
> an issue is gpiochip_set_names() as pointed out by Bartosz.
> If you can live without the names you can remove that part for
> now and we can merge the driver, then you can add the names
> later when we sorted out how to share that function.
I raised the concerns about missing gpio line names in the first version
of patch, without knowing the real efforts.

So I'm fine with Linus' suggestion, because I don't want to delay the
upstreaming effort unnecessarily.

Regards
>
> Yours,
> Linus Walleij

Hi Stefan,

On 12:08 Fri 11 Oct     , Stefan Wahren wrote:
> Am 11.10.24 um 11:03 schrieb Linus Walleij:
> > On Mon, Oct 7, 2024 at 2:39 PM Andrea della Porta <andrea.porta@suse.com> wrote:
> > 
> > > The RP1 is an MFD supporting a gpio controller and /pinmux/pinctrl.
> > > Add minimum support for the gpio only portion. The driver is in
> > > pinctrl folder since upcoming patches will add the pinmux/pinctrl
> > > support where the gpio part can be seen as an addition.
> > > 
> > > Signed-off-by: Andrea della Porta <andrea.porta@suse.com>
> > This is a nice driver and I find no issues with it, what causes
> > an issue is gpiochip_set_names() as pointed out by Bartosz.
> > If you can live without the names you can remove that part for
> > now and we can merge the driver, then you can add the names
> > later when we sorted out how to share that function.
> I raised the concerns about missing gpio line names in the first version
> of patch, without knowing the real efforts.
> 
> So I'm fine with Linus' suggestion, because I don't want to delay the
> upstreaming effort unnecessarily.

Perfect, thanks.

Regards,
Andrea

> 
> Regards
> > 
> > Yours,
> > Linus Walleij
>