| // SPDX-License-Identifier: GPL-2.0-only | 
 | /* | 
 |  * Intel Granite Rapids-D vGPIO driver | 
 |  * | 
 |  * Copyright (c) 2024, Intel Corporation. | 
 |  * | 
 |  * Author: Aapo Vienamo <aapo.vienamo@linux.intel.com> | 
 |  */ | 
 |  | 
 | #include <linux/array_size.h> | 
 | #include <linux/bitfield.h> | 
 | #include <linux/bitmap.h> | 
 | #include <linux/cleanup.h> | 
 | #include <linux/device.h> | 
 | #include <linux/err.h> | 
 | #include <linux/gfp_types.h> | 
 | #include <linux/interrupt.h> | 
 | #include <linux/io.h> | 
 | #include <linux/irq.h> | 
 | #include <linux/math.h> | 
 | #include <linux/mod_devicetable.h> | 
 | #include <linux/module.h> | 
 | #include <linux/overflow.h> | 
 | #include <linux/platform_device.h> | 
 | #include <linux/pm.h> | 
 | #include <linux/spinlock.h> | 
 | #include <linux/types.h> | 
 |  | 
 | #include <linux/gpio/driver.h> | 
 |  | 
 | #define GNR_NUM_PINS 128 | 
 | #define GNR_PINS_PER_REG 32 | 
 | #define GNR_NUM_REGS DIV_ROUND_UP(GNR_NUM_PINS, GNR_PINS_PER_REG) | 
 |  | 
 | #define GNR_CFG_PADBAR		0x00 | 
 | #define GNR_CFG_LOCK_OFFSET	0x04 | 
 | #define GNR_GPI_STATUS_OFFSET	0x14 | 
 | #define GNR_GPI_ENABLE_OFFSET	0x24 | 
 |  | 
 | #define GNR_CFG_DW_HOSTSW_MODE	BIT(27) | 
 | #define GNR_CFG_DW_RX_MASK	GENMASK(23, 22) | 
 | #define GNR_CFG_DW_INTSEL_MASK	GENMASK(21, 14) | 
 | #define GNR_CFG_DW_RX_DISABLE	FIELD_PREP(GNR_CFG_DW_RX_MASK, 2) | 
 | #define GNR_CFG_DW_RX_EDGE	FIELD_PREP(GNR_CFG_DW_RX_MASK, 1) | 
 | #define GNR_CFG_DW_RX_LEVEL	FIELD_PREP(GNR_CFG_DW_RX_MASK, 0) | 
 | #define GNR_CFG_DW_RXDIS	BIT(4) | 
 | #define GNR_CFG_DW_TXDIS	BIT(3) | 
 | #define GNR_CFG_DW_RXSTATE	BIT(1) | 
 | #define GNR_CFG_DW_TXSTATE	BIT(0) | 
 |  | 
 | /** | 
 |  * struct gnr_gpio - Intel Granite Rapids-D vGPIO driver state | 
 |  * @gc: GPIO controller interface | 
 |  * @reg_base: base address of the GPIO registers | 
 |  * @pad_base: base address of the vGPIO pad configuration registers | 
 |  * @ro_bitmap: bitmap of read-only pins | 
 |  * @lock: guard the registers | 
 |  * @pad_backup: backup of the register state for suspend | 
 |  */ | 
 | struct gnr_gpio { | 
 | 	struct gpio_chip gc; | 
 | 	void __iomem *reg_base; | 
 | 	void __iomem *pad_base; | 
 | 	DECLARE_BITMAP(ro_bitmap, GNR_NUM_PINS); | 
 | 	raw_spinlock_t lock; | 
 | 	u32 pad_backup[]; | 
 | }; | 
 |  | 
 | static void __iomem *gnr_gpio_get_padcfg_addr(const struct gnr_gpio *priv, | 
 | 					      unsigned int gpio) | 
 | { | 
 | 	return priv->pad_base + gpio * sizeof(u32); | 
 | } | 
 |  | 
 | static int gnr_gpio_configure_line(struct gpio_chip *gc, unsigned int gpio, | 
 | 				   u32 clear_mask, u32 set_mask) | 
 | { | 
 | 	struct gnr_gpio *priv = gpiochip_get_data(gc); | 
 | 	void __iomem *addr = gnr_gpio_get_padcfg_addr(priv, gpio); | 
 | 	u32 dw; | 
 |  | 
 | 	if (test_bit(gpio, priv->ro_bitmap)) | 
 | 		return -EACCES; | 
 |  | 
 | 	guard(raw_spinlock_irqsave)(&priv->lock); | 
 |  | 
 | 	dw = readl(addr); | 
 | 	dw &= ~clear_mask; | 
 | 	dw |= set_mask; | 
 | 	writel(dw, addr); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int gnr_gpio_request(struct gpio_chip *gc, unsigned int gpio) | 
 | { | 
 | 	struct gnr_gpio *priv = gpiochip_get_data(gc); | 
 | 	u32 dw; | 
 |  | 
 | 	dw = readl(gnr_gpio_get_padcfg_addr(priv, gpio)); | 
 | 	if (!(dw & GNR_CFG_DW_HOSTSW_MODE)) { | 
 | 		dev_warn(gc->parent, "GPIO %u is not owned by host", gpio); | 
 | 		return -EBUSY; | 
 | 	} | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int gnr_gpio_get(struct gpio_chip *gc, unsigned int gpio) | 
 | { | 
 | 	const struct gnr_gpio *priv = gpiochip_get_data(gc); | 
 | 	u32 dw; | 
 |  | 
 | 	dw = readl(gnr_gpio_get_padcfg_addr(priv, gpio)); | 
 |  | 
 | 	return !!(dw & GNR_CFG_DW_RXSTATE); | 
 | } | 
 |  | 
 | static void gnr_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value) | 
 | { | 
 | 	u32 clear = 0; | 
 | 	u32 set = 0; | 
 |  | 
 | 	if (value) | 
 | 		set = GNR_CFG_DW_TXSTATE; | 
 | 	else | 
 | 		clear = GNR_CFG_DW_TXSTATE; | 
 |  | 
 | 	gnr_gpio_configure_line(gc, gpio, clear, set); | 
 | } | 
 |  | 
 | static int gnr_gpio_get_direction(struct gpio_chip *gc, unsigned int gpio) | 
 | { | 
 | 	struct gnr_gpio *priv = gpiochip_get_data(gc); | 
 | 	u32 dw; | 
 |  | 
 | 	dw = readl(gnr_gpio_get_padcfg_addr(priv, gpio)); | 
 |  | 
 | 	if (dw & GNR_CFG_DW_TXDIS) | 
 | 		return GPIO_LINE_DIRECTION_IN; | 
 |  | 
 | 	return GPIO_LINE_DIRECTION_OUT; | 
 | } | 
 |  | 
 | static int gnr_gpio_direction_input(struct gpio_chip *gc, unsigned int gpio) | 
 | { | 
 | 	return gnr_gpio_configure_line(gc, gpio, GNR_CFG_DW_RXDIS, 0); | 
 | } | 
 |  | 
 | static int gnr_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio, int value) | 
 | { | 
 | 	u32 clear = GNR_CFG_DW_TXDIS; | 
 | 	u32 set = value ? GNR_CFG_DW_TXSTATE : 0; | 
 |  | 
 | 	return gnr_gpio_configure_line(gc, gpio, clear, set); | 
 | } | 
 |  | 
 | static const struct gpio_chip gnr_gpio_chip = { | 
 | 	.owner		  = THIS_MODULE, | 
 | 	.request	  = gnr_gpio_request, | 
 | 	.get		  = gnr_gpio_get, | 
 | 	.set		  = gnr_gpio_set, | 
 | 	.get_direction    = gnr_gpio_get_direction, | 
 | 	.direction_input  = gnr_gpio_direction_input, | 
 | 	.direction_output = gnr_gpio_direction_output, | 
 | }; | 
 |  | 
 | static void __iomem *gnr_gpio_get_reg_addr(const struct gnr_gpio *priv, | 
 | 					   unsigned int base, | 
 | 					   unsigned int gpio) | 
 | { | 
 | 	return priv->reg_base + base + gpio * sizeof(u32); | 
 | } | 
 |  | 
 | static void gnr_gpio_irq_ack(struct irq_data *d) | 
 | { | 
 | 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d); | 
 | 	struct gnr_gpio *priv = gpiochip_get_data(gc); | 
 | 	irq_hw_number_t gpio = irqd_to_hwirq(d); | 
 | 	unsigned int reg_idx = gpio / GNR_PINS_PER_REG; | 
 | 	unsigned int bit_idx = gpio % GNR_PINS_PER_REG; | 
 | 	void __iomem *addr = gnr_gpio_get_reg_addr(priv, GNR_GPI_STATUS_OFFSET, reg_idx); | 
 | 	u32 reg; | 
 |  | 
 | 	guard(raw_spinlock_irqsave)(&priv->lock); | 
 |  | 
 | 	reg = readl(addr); | 
 | 	reg |= BIT(bit_idx); | 
 | 	writel(reg, addr); | 
 | } | 
 |  | 
 | static void gnr_gpio_irq_mask_unmask(struct gpio_chip *gc, unsigned long gpio, bool mask) | 
 | { | 
 | 	struct gnr_gpio *priv = gpiochip_get_data(gc); | 
 | 	unsigned int reg_idx = gpio / GNR_PINS_PER_REG; | 
 | 	unsigned int bit_idx = gpio % GNR_PINS_PER_REG; | 
 | 	void __iomem *addr = gnr_gpio_get_reg_addr(priv, GNR_GPI_ENABLE_OFFSET, reg_idx); | 
 | 	u32 reg; | 
 |  | 
 | 	guard(raw_spinlock_irqsave)(&priv->lock); | 
 |  | 
 | 	reg = readl(addr); | 
 | 	if (mask) | 
 | 		reg &= ~BIT(bit_idx); | 
 | 	else | 
 | 		reg |= BIT(bit_idx); | 
 | 	writel(reg, addr); | 
 | } | 
 |  | 
 | static void gnr_gpio_irq_mask(struct irq_data *d) | 
 | { | 
 | 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d); | 
 | 	irq_hw_number_t hwirq = irqd_to_hwirq(d); | 
 |  | 
 | 	gnr_gpio_irq_mask_unmask(gc, hwirq, true); | 
 | 	gpiochip_disable_irq(gc, hwirq); | 
 | } | 
 |  | 
 | static void gnr_gpio_irq_unmask(struct irq_data *d) | 
 | { | 
 | 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d); | 
 | 	irq_hw_number_t hwirq = irqd_to_hwirq(d); | 
 |  | 
 | 	gpiochip_enable_irq(gc, hwirq); | 
 | 	gnr_gpio_irq_mask_unmask(gc, hwirq, false); | 
 | } | 
 |  | 
 | static int gnr_gpio_irq_set_type(struct irq_data *d, unsigned int type) | 
 | { | 
 | 	struct gpio_chip *gc = irq_data_get_irq_chip_data(d); | 
 | 	struct gnr_gpio *priv = gpiochip_get_data(gc); | 
 | 	irq_hw_number_t hwirq = irqd_to_hwirq(d); | 
 | 	u32 reg; | 
 | 	u32 set; | 
 |  | 
 | 	/* Allow interrupts only if Interrupt Select field is non-zero */ | 
 | 	reg = readl(gnr_gpio_get_padcfg_addr(priv, hwirq)); | 
 | 	if (!(reg & GNR_CFG_DW_INTSEL_MASK)) { | 
 | 		dev_dbg(gc->parent, "GPIO %lu cannot be used as IRQ", hwirq); | 
 | 		return -EPERM; | 
 | 	} | 
 |  | 
 | 	/* Falling edge and level low triggers not supported by the GPIO controller */ | 
 | 	switch (type) { | 
 | 	case IRQ_TYPE_NONE: | 
 | 		set = GNR_CFG_DW_RX_DISABLE; | 
 | 		break; | 
 | 	case IRQ_TYPE_EDGE_RISING: | 
 | 		set = GNR_CFG_DW_RX_EDGE; | 
 | 		irq_set_handler_locked(d, handle_edge_irq); | 
 | 		break; | 
 | 	case IRQ_TYPE_LEVEL_HIGH: | 
 | 		set = GNR_CFG_DW_RX_LEVEL; | 
 | 		irq_set_handler_locked(d, handle_level_irq); | 
 | 		break; | 
 | 	default: | 
 | 		return -EINVAL; | 
 | 	} | 
 |  | 
 | 	return gnr_gpio_configure_line(gc, hwirq, GNR_CFG_DW_RX_MASK, set); | 
 | } | 
 |  | 
 | static const struct irq_chip gnr_gpio_irq_chip = { | 
 | 	.name		= "gpio-graniterapids", | 
 | 	.irq_ack	= gnr_gpio_irq_ack, | 
 | 	.irq_mask	= gnr_gpio_irq_mask, | 
 | 	.irq_unmask	= gnr_gpio_irq_unmask, | 
 | 	.irq_set_type	= gnr_gpio_irq_set_type, | 
 | 	.flags		= IRQCHIP_IMMUTABLE, | 
 | 	GPIOCHIP_IRQ_RESOURCE_HELPERS, | 
 | }; | 
 |  | 
 | static void gnr_gpio_init_pin_ro_bits(struct device *dev, | 
 | 				      const void __iomem *cfg_lock_base, | 
 | 				      unsigned long *ro_bitmap) | 
 | { | 
 | 	u32 tmp[GNR_NUM_REGS]; | 
 |  | 
 | 	memcpy_fromio(tmp, cfg_lock_base, sizeof(tmp)); | 
 | 	bitmap_from_arr32(ro_bitmap, tmp, GNR_NUM_PINS); | 
 | } | 
 |  | 
 | static irqreturn_t gnr_gpio_irq(int irq, void *data) | 
 | { | 
 | 	struct gnr_gpio *priv = data; | 
 | 	unsigned int handled = 0; | 
 |  | 
 | 	for (unsigned int i = 0; i < GNR_NUM_REGS; i++) { | 
 | 		const void __iomem *reg = priv->reg_base + i * sizeof(u32); | 
 | 		unsigned long pending; | 
 | 		unsigned long enabled; | 
 | 		unsigned int bit_idx; | 
 |  | 
 | 		scoped_guard(raw_spinlock, &priv->lock) { | 
 | 			pending = readl(reg + GNR_GPI_STATUS_OFFSET); | 
 | 			enabled = readl(reg + GNR_GPI_ENABLE_OFFSET); | 
 | 		} | 
 |  | 
 | 		/* Only enabled interrupts */ | 
 | 		pending &= enabled; | 
 |  | 
 | 		for_each_set_bit(bit_idx, &pending, GNR_PINS_PER_REG) { | 
 | 			unsigned int hwirq = i * GNR_PINS_PER_REG + bit_idx; | 
 |  | 
 | 			generic_handle_domain_irq(priv->gc.irq.domain, hwirq); | 
 | 		} | 
 |  | 
 | 		handled += pending ? 1 : 0; | 
 |  | 
 | 	} | 
 | 	return IRQ_RETVAL(handled); | 
 | } | 
 |  | 
 | static int gnr_gpio_probe(struct platform_device *pdev) | 
 | { | 
 | 	size_t num_backup_pins = IS_ENABLED(CONFIG_PM_SLEEP) ? GNR_NUM_PINS : 0; | 
 | 	struct device *dev = &pdev->dev; | 
 | 	struct gpio_irq_chip *girq; | 
 | 	struct gnr_gpio *priv; | 
 | 	void __iomem *regs; | 
 | 	int irq, ret; | 
 | 	u32 offset; | 
 |  | 
 | 	priv = devm_kzalloc(dev, struct_size(priv, pad_backup, num_backup_pins), GFP_KERNEL); | 
 | 	if (!priv) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	raw_spin_lock_init(&priv->lock); | 
 |  | 
 | 	regs = devm_platform_ioremap_resource(pdev, 0); | 
 | 	if (IS_ERR(regs)) | 
 | 		return PTR_ERR(regs); | 
 |  | 
 | 	priv->reg_base = regs; | 
 | 	offset = readl(priv->reg_base + GNR_CFG_PADBAR); | 
 | 	priv->pad_base = priv->reg_base + offset; | 
 |  | 
 | 	irq = platform_get_irq(pdev, 0); | 
 | 	if (irq < 0) | 
 | 		return irq; | 
 |  | 
 | 	ret = devm_request_irq(dev, irq, gnr_gpio_irq, IRQF_SHARED | IRQF_NO_THREAD, | 
 | 			       dev_name(dev), priv); | 
 | 	if (ret) | 
 | 		return dev_err_probe(dev, ret, "failed to request interrupt\n"); | 
 |  | 
 | 	gnr_gpio_init_pin_ro_bits(dev, priv->reg_base + GNR_CFG_LOCK_OFFSET, | 
 | 				  priv->ro_bitmap); | 
 |  | 
 | 	priv->gc	= gnr_gpio_chip; | 
 | 	priv->gc.label	= dev_name(dev); | 
 | 	priv->gc.parent	= dev; | 
 | 	priv->gc.ngpio	= GNR_NUM_PINS; | 
 | 	priv->gc.base	= -1; | 
 |  | 
 | 	girq = &priv->gc.irq; | 
 | 	gpio_irq_chip_set_chip(girq, &gnr_gpio_irq_chip); | 
 | 	girq->parent_handler	= NULL; | 
 | 	girq->num_parents	= 0; | 
 | 	girq->parents		= NULL; | 
 | 	girq->default_type	= IRQ_TYPE_NONE; | 
 | 	girq->handler		= handle_bad_irq; | 
 |  | 
 | 	platform_set_drvdata(pdev, priv); | 
 |  | 
 | 	return devm_gpiochip_add_data(dev, &priv->gc, priv); | 
 | } | 
 |  | 
 | static int gnr_gpio_suspend(struct device *dev) | 
 | { | 
 | 	struct gnr_gpio *priv = dev_get_drvdata(dev); | 
 | 	unsigned int i; | 
 |  | 
 | 	guard(raw_spinlock_irqsave)(&priv->lock); | 
 |  | 
 | 	for_each_clear_bit(i, priv->ro_bitmap, priv->gc.ngpio) | 
 | 		priv->pad_backup[i] = readl(gnr_gpio_get_padcfg_addr(priv, i)); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int gnr_gpio_resume(struct device *dev) | 
 | { | 
 | 	struct gnr_gpio *priv = dev_get_drvdata(dev); | 
 | 	unsigned int i; | 
 |  | 
 | 	guard(raw_spinlock_irqsave)(&priv->lock); | 
 |  | 
 | 	for_each_clear_bit(i, priv->ro_bitmap, priv->gc.ngpio) | 
 | 		writel(priv->pad_backup[i], gnr_gpio_get_padcfg_addr(priv, i)); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static DEFINE_SIMPLE_DEV_PM_OPS(gnr_gpio_pm_ops, gnr_gpio_suspend, gnr_gpio_resume); | 
 |  | 
 | static const struct acpi_device_id gnr_gpio_acpi_match[] = { | 
 | 	{ "INTC1109" }, | 
 | 	{} | 
 | }; | 
 | MODULE_DEVICE_TABLE(acpi, gnr_gpio_acpi_match); | 
 |  | 
 | static struct platform_driver gnr_gpio_driver = { | 
 | 	.driver = { | 
 | 		.name		  = "gpio-graniterapids", | 
 | 		.pm		  = pm_sleep_ptr(&gnr_gpio_pm_ops), | 
 | 		.acpi_match_table = gnr_gpio_acpi_match, | 
 | 	}, | 
 | 	.probe = gnr_gpio_probe, | 
 | }; | 
 | module_platform_driver(gnr_gpio_driver); | 
 |  | 
 | MODULE_LICENSE("GPL"); | 
 | MODULE_AUTHOR("Aapo Vienamo <aapo.vienamo@linux.intel.com>"); | 
 | MODULE_DESCRIPTION("Intel Granite Rapids-D vGPIO driver"); |