Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1280 insertions, 0 deletions

diff --git a/drivers/gpio/gpio-aspeed.c b/drivers/gpio/gpio-aspeed.c
new file mode 100644
index 0000000000..58f107194f
--- /dev/null
+++ b/drivers/gpio/gpio-aspeed.c
@@ -0,0 +1,1280 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2015 IBM Corp.
+ *
+ * Joel Stanley <joel@jms.id.au>
+ */
+
+#include <linux/clk.h>
+#include <linux/gpio/aspeed.h>
+#include <linux/gpio/driver.h>
+#include <linux/hashtable.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/seq_file.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+
+#include <asm/div64.h>
+
+/*
+ * These two headers aren't meant to be used by GPIO drivers. We need
+ * them in order to access gpio_chip_hwgpio() which we need to implement
+ * the aspeed specific API which allows the coprocessor to request
+ * access to some GPIOs and to arbitrate between coprocessor and ARM.
+ */
+#include <linux/gpio/consumer.h>
+#include "gpiolib.h"
+
+struct aspeed_bank_props {
+	unsigned int bank;
+	u32 input;
+	u32 output;
+};
+
+struct aspeed_gpio_config {
+	unsigned int nr_gpios;
+	const struct aspeed_bank_props *props;
+};
+
+/*
+ * @offset_timer: Maps an offset to an @timer_users index, or zero if disabled
+ * @timer_users: Tracks the number of users for each timer
+ *
+ * The @timer_users has four elements but the first element is unused. This is
+ * to simplify accounting and indexing, as a zero value in @offset_timer
+ * represents disabled debouncing for the GPIO. Any other value for an element
+ * of @offset_timer is used as an index into @timer_users. This behaviour of
+ * the zero value aligns with the behaviour of zero built from the timer
+ * configuration registers (i.e. debouncing is disabled).
+ */
+struct aspeed_gpio {
+	struct gpio_chip chip;
+	struct device *dev;
+	raw_spinlock_t lock;
+	void __iomem *base;
+	int irq;
+	const struct aspeed_gpio_config *config;
+
+	u8 *offset_timer;
+	unsigned int timer_users[4];
+	struct clk *clk;
+
+	u32 *dcache;
+	u8 *cf_copro_bankmap;
+};
+
+struct aspeed_gpio_bank {
+	uint16_t	val_regs;	/* +0: Rd: read input value, Wr: set write latch
+					 * +4: Rd/Wr: Direction (0=in, 1=out)
+					 */
+	uint16_t	rdata_reg;	/*     Rd: read write latch, Wr: <none>  */
+	uint16_t	irq_regs;
+	uint16_t	debounce_regs;
+	uint16_t	tolerance_regs;
+	uint16_t	cmdsrc_regs;
+	const char	names[4][3];
+};
+
+/*
+ * Note: The "value" register returns the input value sampled on the
+ *       line even when the GPIO is configured as an output. Since
+ *       that input goes through synchronizers, writing, then reading
+ *       back may not return the written value right away.
+ *
+ *       The "rdata" register returns the content of the write latch
+ *       and thus can be used to read back what was last written
+ *       reliably.
+ */
+
+static const int debounce_timers[4] = { 0x00, 0x50, 0x54, 0x58 };
+
+static const struct aspeed_gpio_copro_ops *copro_ops;
+static void *copro_data;
+
+static const struct aspeed_gpio_bank aspeed_gpio_banks[] = {
+	{
+		.val_regs = 0x0000,
+		.rdata_reg = 0x00c0,
+		.irq_regs = 0x0008,
+		.debounce_regs = 0x0040,
+		.tolerance_regs = 0x001c,
+		.cmdsrc_regs = 0x0060,
+		.names = { "A", "B", "C", "D" },
+	},
+	{
+		.val_regs = 0x0020,
+		.rdata_reg = 0x00c4,
+		.irq_regs = 0x0028,
+		.debounce_regs = 0x0048,
+		.tolerance_regs = 0x003c,
+		.cmdsrc_regs = 0x0068,
+		.names = { "E", "F", "G", "H" },
+	},
+	{
+		.val_regs = 0x0070,
+		.rdata_reg = 0x00c8,
+		.irq_regs = 0x0098,
+		.debounce_regs = 0x00b0,
+		.tolerance_regs = 0x00ac,
+		.cmdsrc_regs = 0x0090,
+		.names = { "I", "J", "K", "L" },
+	},
+	{
+		.val_regs = 0x0078,
+		.rdata_reg = 0x00cc,
+		.irq_regs = 0x00e8,
+		.debounce_regs = 0x0100,
+		.tolerance_regs = 0x00fc,
+		.cmdsrc_regs = 0x00e0,
+		.names = { "M", "N", "O", "P" },
+	},
+	{
+		.val_regs = 0x0080,
+		.rdata_reg = 0x00d0,
+		.irq_regs = 0x0118,
+		.debounce_regs = 0x0130,
+		.tolerance_regs = 0x012c,
+		.cmdsrc_regs = 0x0110,
+		.names = { "Q", "R", "S", "T" },
+	},
+	{
+		.val_regs = 0x0088,
+		.rdata_reg = 0x00d4,
+		.irq_regs = 0x0148,
+		.debounce_regs = 0x0160,
+		.tolerance_regs = 0x015c,
+		.cmdsrc_regs = 0x0140,
+		.names = { "U", "V", "W", "X" },
+	},
+	{
+		.val_regs = 0x01E0,
+		.rdata_reg = 0x00d8,
+		.irq_regs = 0x0178,
+		.debounce_regs = 0x0190,
+		.tolerance_regs = 0x018c,
+		.cmdsrc_regs = 0x0170,
+		.names = { "Y", "Z", "AA", "AB" },
+	},
+	{
+		.val_regs = 0x01e8,
+		.rdata_reg = 0x00dc,
+		.irq_regs = 0x01a8,
+		.debounce_regs = 0x01c0,
+		.tolerance_regs = 0x01bc,
+		.cmdsrc_regs = 0x01a0,
+		.names = { "AC", "", "", "" },
+	},
+};
+
+enum aspeed_gpio_reg {
+	reg_val,
+	reg_rdata,
+	reg_dir,
+	reg_irq_enable,
+	reg_irq_type0,
+	reg_irq_type1,
+	reg_irq_type2,
+	reg_irq_status,
+	reg_debounce_sel1,
+	reg_debounce_sel2,
+	reg_tolerance,
+	reg_cmdsrc0,
+	reg_cmdsrc1,
+};
+
+#define GPIO_VAL_VALUE	0x00
+#define GPIO_VAL_DIR	0x04
+
+#define GPIO_IRQ_ENABLE	0x00
+#define GPIO_IRQ_TYPE0	0x04
+#define GPIO_IRQ_TYPE1	0x08
+#define GPIO_IRQ_TYPE2	0x0c
+#define GPIO_IRQ_STATUS	0x10
+
+#define GPIO_DEBOUNCE_SEL1 0x00
+#define GPIO_DEBOUNCE_SEL2 0x04
+
+#define GPIO_CMDSRC_0	0x00
+#define GPIO_CMDSRC_1	0x04
+#define  GPIO_CMDSRC_ARM		0
+#define  GPIO_CMDSRC_LPC		1
+#define  GPIO_CMDSRC_COLDFIRE		2
+#define  GPIO_CMDSRC_RESERVED		3
+
+/* This will be resolved at compile time */
+static inline void __iomem *bank_reg(struct aspeed_gpio *gpio,
+				     const struct aspeed_gpio_bank *bank,
+				     const enum aspeed_gpio_reg reg)
+{
+	switch (reg) {
+	case reg_val:
+		return gpio->base + bank->val_regs + GPIO_VAL_VALUE;
+	case reg_rdata:
+		return gpio->base + bank->rdata_reg;
+	case reg_dir:
+		return gpio->base + bank->val_regs + GPIO_VAL_DIR;
+	case reg_irq_enable:
+		return gpio->base + bank->irq_regs + GPIO_IRQ_ENABLE;
+	case reg_irq_type0:
+		return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE0;
+	case reg_irq_type1:
+		return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE1;
+	case reg_irq_type2:
+		return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE2;
+	case reg_irq_status:
+		return gpio->base + bank->irq_regs + GPIO_IRQ_STATUS;
+	case reg_debounce_sel1:
+		return gpio->base + bank->debounce_regs + GPIO_DEBOUNCE_SEL1;
+	case reg_debounce_sel2:
+		return gpio->base + bank->debounce_regs + GPIO_DEBOUNCE_SEL2;
+	case reg_tolerance:
+		return gpio->base + bank->tolerance_regs;
+	case reg_cmdsrc0:
+		return gpio->base + bank->cmdsrc_regs + GPIO_CMDSRC_0;
+	case reg_cmdsrc1:
+		return gpio->base + bank->cmdsrc_regs + GPIO_CMDSRC_1;
+	}
+	BUG();
+}
+
+#define GPIO_BANK(x)	((x) >> 5)
+#define GPIO_OFFSET(x)	((x) & 0x1f)
+#define GPIO_BIT(x)	BIT(GPIO_OFFSET(x))
+
+#define _GPIO_SET_DEBOUNCE(t, o, i) ((!!((t) & BIT(i))) << GPIO_OFFSET(o))
+#define GPIO_SET_DEBOUNCE1(t, o) _GPIO_SET_DEBOUNCE(t, o, 1)
+#define GPIO_SET_DEBOUNCE2(t, o) _GPIO_SET_DEBOUNCE(t, o, 0)
+
+static const struct aspeed_gpio_bank *to_bank(unsigned int offset)
+{
+	unsigned int bank = GPIO_BANK(offset);
+
+	WARN_ON(bank >= ARRAY_SIZE(aspeed_gpio_banks));
+	return &aspeed_gpio_banks[bank];
+}
+
+static inline bool is_bank_props_sentinel(const struct aspeed_bank_props *props)
+{
+	return !(props->input || props->output);
+}
+
+static inline const struct aspeed_bank_props *find_bank_props(
+		struct aspeed_gpio *gpio, unsigned int offset)
+{
+	const struct aspeed_bank_props *props = gpio->config->props;
+
+	while (!is_bank_props_sentinel(props)) {
+		if (props->bank == GPIO_BANK(offset))
+			return props;
+		props++;
+	}
+
+	return NULL;
+}
+
+static inline bool have_gpio(struct aspeed_gpio *gpio, unsigned int offset)
+{
+	const struct aspeed_bank_props *props = find_bank_props(gpio, offset);
+	const struct aspeed_gpio_bank *bank = to_bank(offset);
+	unsigned int group = GPIO_OFFSET(offset) / 8;
+
+	return bank->names[group][0] != '\0' &&
+		(!props || ((props->input | props->output) & GPIO_BIT(offset)));
+}
+
+static inline bool have_input(struct aspeed_gpio *gpio, unsigned int offset)
+{
+	const struct aspeed_bank_props *props = find_bank_props(gpio, offset);
+
+	return !props || (props->input & GPIO_BIT(offset));
+}
+
+#define have_irq(g, o) have_input((g), (o))
+#define have_debounce(g, o) have_input((g), (o))
+
+static inline bool have_output(struct aspeed_gpio *gpio, unsigned int offset)
+{
+	const struct aspeed_bank_props *props = find_bank_props(gpio, offset);
+
+	return !props || (props->output & GPIO_BIT(offset));
+}
+
+static void aspeed_gpio_change_cmd_source(struct aspeed_gpio *gpio,
+					  const struct aspeed_gpio_bank *bank,
+					  int bindex, int cmdsrc)
+{
+	void __iomem *c0 = bank_reg(gpio, bank, reg_cmdsrc0);
+	void __iomem *c1 = bank_reg(gpio, bank, reg_cmdsrc1);
+	u32 bit, reg;
+
+	/*
+	 * Each register controls 4 banks, so take the bottom 2
+	 * bits of the bank index, and use them to select the
+	 * right control bit (0, 8, 16 or 24).
+	 */
+	bit = BIT((bindex & 3) << 3);
+
+	/* Source 1 first to avoid illegal 11 combination */
+	reg = ioread32(c1);
+	if (cmdsrc & 2)
+		reg |= bit;
+	else
+		reg &= ~bit;
+	iowrite32(reg, c1);
+
+	/* Then Source 0 */
+	reg = ioread32(c0);
+	if (cmdsrc & 1)
+		reg |= bit;
+	else
+		reg &= ~bit;
+	iowrite32(reg, c0);
+}
+
+static bool aspeed_gpio_copro_request(struct aspeed_gpio *gpio,
+				      unsigned int offset)
+{
+	const struct aspeed_gpio_bank *bank = to_bank(offset);
+
+	if (!copro_ops || !gpio->cf_copro_bankmap)
+		return false;
+	if (!gpio->cf_copro_bankmap[offset >> 3])
+		return false;
+	if (!copro_ops->request_access)
+		return false;
+
+	/* Pause the coprocessor */
+	copro_ops->request_access(copro_data);
+
+	/* Change command source back to ARM */
+	aspeed_gpio_change_cmd_source(gpio, bank, offset >> 3, GPIO_CMDSRC_ARM);
+
+	/* Update cache */
+	gpio->dcache[GPIO_BANK(offset)] = ioread32(bank_reg(gpio, bank, reg_rdata));
+
+	return true;
+}
+
+static void aspeed_gpio_copro_release(struct aspeed_gpio *gpio,
+				      unsigned int offset)
+{
+	const struct aspeed_gpio_bank *bank = to_bank(offset);
+
+	if (!copro_ops || !gpio->cf_copro_bankmap)
+		return;
+	if (!gpio->cf_copro_bankmap[offset >> 3])
+		return;
+	if (!copro_ops->release_access)
+		return;
+
+	/* Change command source back to ColdFire */
+	aspeed_gpio_change_cmd_source(gpio, bank, offset >> 3,
+				      GPIO_CMDSRC_COLDFIRE);
+
+	/* Restart the coprocessor */
+	copro_ops->release_access(copro_data);
+}
+
+static int aspeed_gpio_get(struct gpio_chip *gc, unsigned int offset)
+{
+	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+	const struct aspeed_gpio_bank *bank = to_bank(offset);
+
+	return !!(ioread32(bank_reg(gpio, bank, reg_val)) & GPIO_BIT(offset));
+}
+
+static void __aspeed_gpio_set(struct gpio_chip *gc, unsigned int offset,
+			      int val)
+{
+	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+	const struct aspeed_gpio_bank *bank = to_bank(offset);
+	void __iomem *addr;
+	u32 reg;
+
+	addr = bank_reg(gpio, bank, reg_val);
+	reg = gpio->dcache[GPIO_BANK(offset)];
+
+	if (val)
+		reg |= GPIO_BIT(offset);
+	else
+		reg &= ~GPIO_BIT(offset);
+	gpio->dcache[GPIO_BANK(offset)] = reg;
+
+	iowrite32(reg, addr);
+}
+
+static void aspeed_gpio_set(struct gpio_chip *gc, unsigned int offset,
+			    int val)
+{
+	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+	unsigned long flags;
+	bool copro;
+
+	raw_spin_lock_irqsave(&gpio->lock, flags);
+	copro = aspeed_gpio_copro_request(gpio, offset);
+
+	__aspeed_gpio_set(gc, offset, val);
+
+	if (copro)
+		aspeed_gpio_copro_release(gpio, offset);
+	raw_spin_unlock_irqrestore(&gpio->lock, flags);
+}
+
+static int aspeed_gpio_dir_in(struct gpio_chip *gc, unsigned int offset)
+{
+	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+	const struct aspeed_gpio_bank *bank = to_bank(offset);
+	void __iomem *addr = bank_reg(gpio, bank, reg_dir);
+	unsigned long flags;
+	bool copro;
+	u32 reg;
+
+	if (!have_input(gpio, offset))
+		return -ENOTSUPP;
+
+	raw_spin_lock_irqsave(&gpio->lock, flags);
+
+	reg = ioread32(addr);
+	reg &= ~GPIO_BIT(offset);
+
+	copro = aspeed_gpio_copro_request(gpio, offset);
+	iowrite32(reg, addr);
+	if (copro)
+		aspeed_gpio_copro_release(gpio, offset);
+
+	raw_spin_unlock_irqrestore(&gpio->lock, flags);
+
+	return 0;
+}
+
+static int aspeed_gpio_dir_out(struct gpio_chip *gc,
+			       unsigned int offset, int val)
+{
+	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+	const struct aspeed_gpio_bank *bank = to_bank(offset);
+	void __iomem *addr = bank_reg(gpio, bank, reg_dir);
+	unsigned long flags;
+	bool copro;
+	u32 reg;
+
+	if (!have_output(gpio, offset))
+		return -ENOTSUPP;
+
+	raw_spin_lock_irqsave(&gpio->lock, flags);
+
+	reg = ioread32(addr);
+	reg |= GPIO_BIT(offset);
+
+	copro = aspeed_gpio_copro_request(gpio, offset);
+	__aspeed_gpio_set(gc, offset, val);
+	iowrite32(reg, addr);
+
+	if (copro)
+		aspeed_gpio_copro_release(gpio, offset);
+	raw_spin_unlock_irqrestore(&gpio->lock, flags);
+
+	return 0;
+}
+
+static int aspeed_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
+{
+	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+	const struct aspeed_gpio_bank *bank = to_bank(offset);
+	unsigned long flags;
+	u32 val;
+
+	if (!have_input(gpio, offset))
+		return GPIO_LINE_DIRECTION_OUT;
+
+	if (!have_output(gpio, offset))
+		return GPIO_LINE_DIRECTION_IN;
+
+	raw_spin_lock_irqsave(&gpio->lock, flags);
+
+	val = ioread32(bank_reg(gpio, bank, reg_dir)) & GPIO_BIT(offset);
+
+	raw_spin_unlock_irqrestore(&gpio->lock, flags);
+
+	return val ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN;
+}
+
+static inline int irqd_to_aspeed_gpio_data(struct irq_data *d,
+					   struct aspeed_gpio **gpio,
+					   const struct aspeed_gpio_bank **bank,
+					   u32 *bit, int *offset)
+{
+	struct aspeed_gpio *internal;
+
+	*offset = irqd_to_hwirq(d);
+
+	internal = irq_data_get_irq_chip_data(d);
+
+	/* This might be a bit of a questionable place to check */
+	if (!have_irq(internal, *offset))
+		return -ENOTSUPP;
+
+	*gpio = internal;
+	*bank = to_bank(*offset);
+	*bit = GPIO_BIT(*offset);
+
+	return 0;
+}
+
+static void aspeed_gpio_irq_ack(struct irq_data *d)
+{
+	const struct aspeed_gpio_bank *bank;
+	struct aspeed_gpio *gpio;
+	unsigned long flags;
+	void __iomem *status_addr;
+	int rc, offset;
+	bool copro;
+	u32 bit;
+
+	rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
+	if (rc)
+		return;
+
+	status_addr = bank_reg(gpio, bank, reg_irq_status);
+
+	raw_spin_lock_irqsave(&gpio->lock, flags);
+	copro = aspeed_gpio_copro_request(gpio, offset);
+
+	iowrite32(bit, status_addr);
+
+	if (copro)
+		aspeed_gpio_copro_release(gpio, offset);
+	raw_spin_unlock_irqrestore(&gpio->lock, flags);
+}
+
+static void aspeed_gpio_irq_set_mask(struct irq_data *d, bool set)
+{
+	const struct aspeed_gpio_bank *bank;
+	struct aspeed_gpio *gpio;
+	unsigned long flags;
+	u32 reg, bit;
+	void __iomem *addr;
+	int rc, offset;
+	bool copro;
+
+	rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
+	if (rc)
+		return;
+
+	addr = bank_reg(gpio, bank, reg_irq_enable);
+
+	/* Unmasking the IRQ */
+	if (set)
+		gpiochip_enable_irq(&gpio->chip, irqd_to_hwirq(d));
+
+	raw_spin_lock_irqsave(&gpio->lock, flags);
+	copro = aspeed_gpio_copro_request(gpio, offset);
+
+	reg = ioread32(addr);
+	if (set)
+		reg |= bit;
+	else
+		reg &= ~bit;
+	iowrite32(reg, addr);
+
+	if (copro)
+		aspeed_gpio_copro_release(gpio, offset);
+	raw_spin_unlock_irqrestore(&gpio->lock, flags);
+
+	/* Masking the IRQ */
+	if (!set)
+		gpiochip_disable_irq(&gpio->chip, irqd_to_hwirq(d));
+}
+
+static void aspeed_gpio_irq_mask(struct irq_data *d)
+{
+	aspeed_gpio_irq_set_mask(d, false);
+}
+
+static void aspeed_gpio_irq_unmask(struct irq_data *d)
+{
+	aspeed_gpio_irq_set_mask(d, true);
+}
+
+static int aspeed_gpio_set_type(struct irq_data *d, unsigned int type)
+{
+	u32 type0 = 0;
+	u32 type1 = 0;
+	u32 type2 = 0;
+	u32 bit, reg;
+	const struct aspeed_gpio_bank *bank;
+	irq_flow_handler_t handler;
+	struct aspeed_gpio *gpio;
+	unsigned long flags;
+	void __iomem *addr;
+	int rc, offset;
+	bool copro;
+
+	rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
+	if (rc)
+		return -EINVAL;
+
+	switch (type & IRQ_TYPE_SENSE_MASK) {
+	case IRQ_TYPE_EDGE_BOTH:
+		type2 |= bit;
+		fallthrough;
+	case IRQ_TYPE_EDGE_RISING:
+		type0 |= bit;
+		fallthrough;
+	case IRQ_TYPE_EDGE_FALLING:
+		handler = handle_edge_irq;
+		break;
+	case IRQ_TYPE_LEVEL_HIGH:
+		type0 |= bit;
+		fallthrough;
+	case IRQ_TYPE_LEVEL_LOW:
+		type1 |= bit;
+		handler = handle_level_irq;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	raw_spin_lock_irqsave(&gpio->lock, flags);
+	copro = aspeed_gpio_copro_request(gpio, offset);
+
+	addr = bank_reg(gpio, bank, reg_irq_type0);
+	reg = ioread32(addr);
+	reg = (reg & ~bit) | type0;
+	iowrite32(reg, addr);
+
+	addr = bank_reg(gpio, bank, reg_irq_type1);
+	reg = ioread32(addr);
+	reg = (reg & ~bit) | type1;
+	iowrite32(reg, addr);
+
+	addr = bank_reg(gpio, bank, reg_irq_type2);
+	reg = ioread32(addr);
+	reg = (reg & ~bit) | type2;
+	iowrite32(reg, addr);
+
+	if (copro)
+		aspeed_gpio_copro_release(gpio, offset);
+	raw_spin_unlock_irqrestore(&gpio->lock, flags);
+
+	irq_set_handler_locked(d, handler);
+
+	return 0;
+}
+
+static void aspeed_gpio_irq_handler(struct irq_desc *desc)
+{
+	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
+	struct irq_chip *ic = irq_desc_get_chip(desc);
+	struct aspeed_gpio *data = gpiochip_get_data(gc);
+	unsigned int i, p, banks;
+	unsigned long reg;
+	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+
+	chained_irq_enter(ic, desc);
+
+	banks = DIV_ROUND_UP(gpio->chip.ngpio, 32);
+	for (i = 0; i < banks; i++) {
+		const struct aspeed_gpio_bank *bank = &aspeed_gpio_banks[i];
+
+		reg = ioread32(bank_reg(data, bank, reg_irq_status));
+
+		for_each_set_bit(p, &reg, 32)
+			generic_handle_domain_irq(gc->irq.domain, i * 32 + p);
+	}
+
+	chained_irq_exit(ic, desc);
+}
+
+static void aspeed_init_irq_valid_mask(struct gpio_chip *gc,
+				       unsigned long *valid_mask,
+				       unsigned int ngpios)
+{
+	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+	const struct aspeed_bank_props *props = gpio->config->props;
+
+	while (!is_bank_props_sentinel(props)) {
+		unsigned int offset;
+		const unsigned long int input = props->input;
+
+		/* Pretty crummy approach, but similar to GPIO core */
+		for_each_clear_bit(offset, &input, 32) {
+			unsigned int i = props->bank * 32 + offset;
+
+			if (i >= gpio->chip.ngpio)
+				break;
+
+			clear_bit(i, valid_mask);
+		}
+
+		props++;
+	}
+}
+
+static int aspeed_gpio_reset_tolerance(struct gpio_chip *chip,
+					unsigned int offset, bool enable)
+{
+	struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+	unsigned long flags;
+	void __iomem *treg;
+	bool copro;
+	u32 val;
+
+	treg = bank_reg(gpio, to_bank(offset), reg_tolerance);
+
+	raw_spin_lock_irqsave(&gpio->lock, flags);
+	copro = aspeed_gpio_copro_request(gpio, offset);
+
+	val = readl(treg);
+
+	if (enable)
+		val |= GPIO_BIT(offset);
+	else
+		val &= ~GPIO_BIT(offset);
+
+	writel(val, treg);
+
+	if (copro)
+		aspeed_gpio_copro_release(gpio, offset);
+	raw_spin_unlock_irqrestore(&gpio->lock, flags);
+
+	return 0;
+}
+
+static int aspeed_gpio_request(struct gpio_chip *chip, unsigned int offset)
+{
+	if (!have_gpio(gpiochip_get_data(chip), offset))
+		return -ENODEV;
+
+	return pinctrl_gpio_request(chip->base + offset);
+}
+
+static void aspeed_gpio_free(struct gpio_chip *chip, unsigned int offset)
+{
+	pinctrl_gpio_free(chip->base + offset);
+}
+
+static int usecs_to_cycles(struct aspeed_gpio *gpio, unsigned long usecs,
+		u32 *cycles)
+{
+	u64 rate;
+	u64 n;
+	u32 r;
+
+	rate = clk_get_rate(gpio->clk);
+	if (!rate)
+		return -ENOTSUPP;
+
+	n = rate * usecs;
+	r = do_div(n, 1000000);
+
+	if (n >= U32_MAX)
+		return -ERANGE;
+
+	/* At least as long as the requested time */
+	*cycles = n + (!!r);
+
+	return 0;
+}
+
+/* Call under gpio->lock */
+static int register_allocated_timer(struct aspeed_gpio *gpio,
+		unsigned int offset, unsigned int timer)
+{
+	if (WARN(gpio->offset_timer[offset] != 0,
+				"Offset %d already allocated timer %d\n",
+				offset, gpio->offset_timer[offset]))
+		return -EINVAL;
+
+	if (WARN(gpio->timer_users[timer] == UINT_MAX,
+				"Timer user count would overflow\n"))
+		return -EPERM;
+
+	gpio->offset_timer[offset] = timer;
+	gpio->timer_users[timer]++;
+
+	return 0;
+}
+
+/* Call under gpio->lock */
+static int unregister_allocated_timer(struct aspeed_gpio *gpio,
+		unsigned int offset)
+{
+	if (WARN(gpio->offset_timer[offset] == 0,
+				"No timer allocated to offset %d\n", offset))
+		return -EINVAL;
+
+	if (WARN(gpio->timer_users[gpio->offset_timer[offset]] == 0,
+				"No users recorded for timer %d\n",
+				gpio->offset_timer[offset]))
+		return -EINVAL;
+
+	gpio->timer_users[gpio->offset_timer[offset]]--;
+	gpio->offset_timer[offset] = 0;
+
+	return 0;
+}
+
+/* Call under gpio->lock */
+static inline bool timer_allocation_registered(struct aspeed_gpio *gpio,
+		unsigned int offset)
+{
+	return gpio->offset_timer[offset] > 0;
+}
+
+/* Call under gpio->lock */
+static void configure_timer(struct aspeed_gpio *gpio, unsigned int offset,
+		unsigned int timer)
+{
+	const struct aspeed_gpio_bank *bank = to_bank(offset);
+	const u32 mask = GPIO_BIT(offset);
+	void __iomem *addr;
+	u32 val;
+
+	/* Note: Debounce timer isn't under control of the command
+	 * source registers, so no need to sync with the coprocessor
+	 */
+	addr = bank_reg(gpio, bank, reg_debounce_sel1);
+	val = ioread32(addr);
+	iowrite32((val & ~mask) | GPIO_SET_DEBOUNCE1(timer, offset), addr);
+
+	addr = bank_reg(gpio, bank, reg_debounce_sel2);
+	val = ioread32(addr);
+	iowrite32((val & ~mask) | GPIO_SET_DEBOUNCE2(timer, offset), addr);
+}
+
+static int enable_debounce(struct gpio_chip *chip, unsigned int offset,
+				    unsigned long usecs)
+{
+	struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+	u32 requested_cycles;
+	unsigned long flags;
+	int rc;
+	int i;
+
+	if (!gpio->clk)
+		return -EINVAL;
+
+	rc = usecs_to_cycles(gpio, usecs, &requested_cycles);
+	if (rc < 0) {
+		dev_warn(chip->parent, "Failed to convert %luus to cycles at %luHz: %d\n",
+				usecs, clk_get_rate(gpio->clk), rc);
+		return rc;
+	}
+
+	raw_spin_lock_irqsave(&gpio->lock, flags);
+
+	if (timer_allocation_registered(gpio, offset)) {
+		rc = unregister_allocated_timer(gpio, offset);
+		if (rc < 0)
+			goto out;
+	}
+
+	/* Try to find a timer already configured for the debounce period */
+	for (i = 1; i < ARRAY_SIZE(debounce_timers); i++) {
+		u32 cycles;
+
+		cycles = ioread32(gpio->base + debounce_timers[i]);
+		if (requested_cycles == cycles)
+			break;
+	}
+
+	if (i == ARRAY_SIZE(debounce_timers)) {
+		int j;
+
+		/*
+		 * As there are no timers configured for the requested debounce
+		 * period, find an unused timer instead
+		 */
+		for (j = 1; j < ARRAY_SIZE(gpio->timer_users); j++) {
+			if (gpio->timer_users[j] == 0)
+				break;
+		}
+
+		if (j == ARRAY_SIZE(gpio->timer_users)) {
+			dev_warn(chip->parent,
+					"Debounce timers exhausted, cannot debounce for period %luus\n",
+					usecs);
+
+			rc = -EPERM;
+
+			/*
+			 * We already adjusted the accounting to remove @offset
+			 * as a user of its previous timer, so also configure
+			 * the hardware so @offset has timers disabled for
+			 * consistency.
+			 */
+			configure_timer(gpio, offset, 0);
+			goto out;
+		}
+
+		i = j;
+
+		iowrite32(requested_cycles, gpio->base + debounce_timers[i]);
+	}
+
+	if (WARN(i == 0, "Cannot register index of disabled timer\n")) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	register_allocated_timer(gpio, offset, i);
+	configure_timer(gpio, offset, i);
+
+out:
+	raw_spin_unlock_irqrestore(&gpio->lock, flags);
+
+	return rc;
+}
+
+static int disable_debounce(struct gpio_chip *chip, unsigned int offset)
+{
+	struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+	unsigned long flags;
+	int rc;
+
+	raw_spin_lock_irqsave(&gpio->lock, flags);
+
+	rc = unregister_allocated_timer(gpio, offset);
+	if (!rc)
+		configure_timer(gpio, offset, 0);
+
+	raw_spin_unlock_irqrestore(&gpio->lock, flags);
+
+	return rc;
+}
+
+static int set_debounce(struct gpio_chip *chip, unsigned int offset,
+				    unsigned long usecs)
+{
+	struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+
+	if (!have_debounce(gpio, offset))
+		return -ENOTSUPP;
+
+	if (usecs)
+		return enable_debounce(chip, offset, usecs);
+
+	return disable_debounce(chip, offset);
+}
+
+static int aspeed_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
+				  unsigned long config)
+{
+	unsigned long param = pinconf_to_config_param(config);
+	u32 arg = pinconf_to_config_argument(config);
+
+	if (param == PIN_CONFIG_INPUT_DEBOUNCE)
+		return set_debounce(chip, offset, arg);
+	else if (param == PIN_CONFIG_BIAS_DISABLE ||
+			param == PIN_CONFIG_BIAS_PULL_DOWN ||
+			param == PIN_CONFIG_DRIVE_STRENGTH)
+		return pinctrl_gpio_set_config(chip->base + offset, config);
+	else if (param == PIN_CONFIG_DRIVE_OPEN_DRAIN ||
+			param == PIN_CONFIG_DRIVE_OPEN_SOURCE)
+		/* Return -ENOTSUPP to trigger emulation, as per datasheet */
+		return -ENOTSUPP;
+	else if (param == PIN_CONFIG_PERSIST_STATE)
+		return aspeed_gpio_reset_tolerance(chip, offset, arg);
+
+	return -ENOTSUPP;
+}
+
+/**
+ * aspeed_gpio_copro_set_ops - Sets the callbacks used for handshaking with
+ *                             the coprocessor for shared GPIO banks
+ * @ops: The callbacks
+ * @data: Pointer passed back to the callbacks
+ */
+int aspeed_gpio_copro_set_ops(const struct aspeed_gpio_copro_ops *ops, void *data)
+{
+	copro_data = data;
+	copro_ops = ops;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(aspeed_gpio_copro_set_ops);
+
+/**
+ * aspeed_gpio_copro_grab_gpio - Mark a GPIO used by the coprocessor. The entire
+ *                               bank gets marked and any access from the ARM will
+ *                               result in handshaking via callbacks.
+ * @desc: The GPIO to be marked
+ * @vreg_offset: If non-NULL, returns the value register offset in the GPIO space
+ * @dreg_offset: If non-NULL, returns the data latch register offset in the GPIO space
+ * @bit: If non-NULL, returns the bit number of the GPIO in the registers
+ */
+int aspeed_gpio_copro_grab_gpio(struct gpio_desc *desc,
+				u16 *vreg_offset, u16 *dreg_offset, u8 *bit)
+{
+	struct gpio_chip *chip = gpiod_to_chip(desc);
+	struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+	int rc = 0, bindex, offset = gpio_chip_hwgpio(desc);
+	const struct aspeed_gpio_bank *bank = to_bank(offset);
+	unsigned long flags;
+
+	if (!gpio->cf_copro_bankmap)
+		gpio->cf_copro_bankmap = kzalloc(gpio->chip.ngpio >> 3, GFP_KERNEL);
+	if (!gpio->cf_copro_bankmap)
+		return -ENOMEM;
+	if (offset < 0 || offset > gpio->chip.ngpio)
+		return -EINVAL;
+	bindex = offset >> 3;
+
+	raw_spin_lock_irqsave(&gpio->lock, flags);
+
+	/* Sanity check, this shouldn't happen */
+	if (gpio->cf_copro_bankmap[bindex] == 0xff) {
+		rc = -EIO;
+		goto bail;
+	}
+	gpio->cf_copro_bankmap[bindex]++;
+
+	/* Switch command source */
+	if (gpio->cf_copro_bankmap[bindex] == 1)
+		aspeed_gpio_change_cmd_source(gpio, bank, bindex,
+					      GPIO_CMDSRC_COLDFIRE);
+
+	if (vreg_offset)
+		*vreg_offset = bank->val_regs;
+	if (dreg_offset)
+		*dreg_offset = bank->rdata_reg;
+	if (bit)
+		*bit = GPIO_OFFSET(offset);
+ bail:
+	raw_spin_unlock_irqrestore(&gpio->lock, flags);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(aspeed_gpio_copro_grab_gpio);
+
+/**
+ * aspeed_gpio_copro_release_gpio - Unmark a GPIO used by the coprocessor.
+ * @desc: The GPIO to be marked
+ */
+int aspeed_gpio_copro_release_gpio(struct gpio_desc *desc)
+{
+	struct gpio_chip *chip = gpiod_to_chip(desc);
+	struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+	int rc = 0, bindex, offset = gpio_chip_hwgpio(desc);
+	const struct aspeed_gpio_bank *bank = to_bank(offset);
+	unsigned long flags;
+
+	if (!gpio->cf_copro_bankmap)
+		return -ENXIO;
+
+	if (offset < 0 || offset > gpio->chip.ngpio)
+		return -EINVAL;
+	bindex = offset >> 3;
+
+	raw_spin_lock_irqsave(&gpio->lock, flags);
+
+	/* Sanity check, this shouldn't happen */
+	if (gpio->cf_copro_bankmap[bindex] == 0) {
+		rc = -EIO;
+		goto bail;
+	}
+	gpio->cf_copro_bankmap[bindex]--;
+
+	/* Switch command source */
+	if (gpio->cf_copro_bankmap[bindex] == 0)
+		aspeed_gpio_change_cmd_source(gpio, bank, bindex,
+					      GPIO_CMDSRC_ARM);
+ bail:
+	raw_spin_unlock_irqrestore(&gpio->lock, flags);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(aspeed_gpio_copro_release_gpio);
+
+static void aspeed_gpio_irq_print_chip(struct irq_data *d, struct seq_file *p)
+{
+	const struct aspeed_gpio_bank *bank;
+	struct aspeed_gpio *gpio;
+	u32 bit;
+	int rc, offset;
+
+	rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
+	if (rc)
+		return;
+
+	seq_printf(p, dev_name(gpio->dev));
+}
+
+static const struct irq_chip aspeed_gpio_irq_chip = {
+	.irq_ack = aspeed_gpio_irq_ack,
+	.irq_mask = aspeed_gpio_irq_mask,
+	.irq_unmask = aspeed_gpio_irq_unmask,
+	.irq_set_type = aspeed_gpio_set_type,
+	.irq_print_chip = aspeed_gpio_irq_print_chip,
+	.flags = IRQCHIP_IMMUTABLE,
+	GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+/*
+ * Any banks not specified in a struct aspeed_bank_props array are assumed to
+ * have the properties:
+ *
+ *     { .input = 0xffffffff, .output = 0xffffffff }
+ */
+
+static const struct aspeed_bank_props ast2400_bank_props[] = {
+	/*     input	  output   */
+	{ 5, 0xffffffff, 0x0000ffff }, /* U/V/W/X */
+	{ 6, 0x0000000f, 0x0fffff0f }, /* Y/Z/AA/AB, two 4-GPIO holes */
+	{ },
+};
+
+static const struct aspeed_gpio_config ast2400_config =
+	/* 220 for simplicity, really 216 with two 4-GPIO holes, four at end */
+	{ .nr_gpios = 220, .props = ast2400_bank_props, };
+
+static const struct aspeed_bank_props ast2500_bank_props[] = {
+	/*     input	  output   */
+	{ 5, 0xffffffff, 0x0000ffff }, /* U/V/W/X */
+	{ 6, 0x0fffffff, 0x0fffffff }, /* Y/Z/AA/AB, 4-GPIO hole */
+	{ 7, 0x000000ff, 0x000000ff }, /* AC */
+	{ },
+};
+
+static const struct aspeed_gpio_config ast2500_config =
+	/* 232 for simplicity, actual number is 228 (4-GPIO hole in GPIOAB) */
+	{ .nr_gpios = 232, .props = ast2500_bank_props, };
+
+static const struct aspeed_bank_props ast2600_bank_props[] = {
+	/*     input	  output   */
+	{4, 0xffffffff,  0x00ffffff}, /* Q/R/S/T */
+	{5, 0xffffffff,  0xffffff00}, /* U/V/W/X */
+	{6, 0x0000ffff,  0x0000ffff}, /* Y/Z */
+	{ },
+};
+
+static const struct aspeed_gpio_config ast2600_config =
+	/*
+	 * ast2600 has two controllers one with 208 GPIOs and one with 36 GPIOs.
+	 * We expect ngpio being set in the device tree and this is a fallback
+	 * option.
+	 */
+	{ .nr_gpios = 208, .props = ast2600_bank_props, };
+
+static const struct of_device_id aspeed_gpio_of_table[] = {
+	{ .compatible = "aspeed,ast2400-gpio", .data = &ast2400_config, },
+	{ .compatible = "aspeed,ast2500-gpio", .data = &ast2500_config, },
+	{ .compatible = "aspeed,ast2600-gpio", .data = &ast2600_config, },
+	{}
+};
+MODULE_DEVICE_TABLE(of, aspeed_gpio_of_table);
+
+static int __init aspeed_gpio_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *gpio_id;
+	struct gpio_irq_chip *girq;
+	struct aspeed_gpio *gpio;
+	int rc, irq, i, banks, err;
+	u32 ngpio;
+
+	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
+	if (!gpio)
+		return -ENOMEM;
+
+	gpio->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(gpio->base))
+		return PTR_ERR(gpio->base);
+
+	gpio->dev = &pdev->dev;
+
+	raw_spin_lock_init(&gpio->lock);
+
+	gpio_id = of_match_node(aspeed_gpio_of_table, pdev->dev.of_node);
+	if (!gpio_id)
+		return -EINVAL;
+
+	gpio->clk = of_clk_get(pdev->dev.of_node, 0);
+	if (IS_ERR(gpio->clk)) {
+		dev_warn(&pdev->dev,
+				"Failed to get clock from devicetree, debouncing disabled\n");
+		gpio->clk = NULL;
+	}
+
+	gpio->config = gpio_id->data;
+
+	gpio->chip.parent = &pdev->dev;
+	err = of_property_read_u32(pdev->dev.of_node, "ngpios", &ngpio);
+	gpio->chip.ngpio = (u16) ngpio;
+	if (err)
+		gpio->chip.ngpio = gpio->config->nr_gpios;
+	gpio->chip.direction_input = aspeed_gpio_dir_in;
+	gpio->chip.direction_output = aspeed_gpio_dir_out;
+	gpio->chip.get_direction = aspeed_gpio_get_direction;
+	gpio->chip.request = aspeed_gpio_request;
+	gpio->chip.free = aspeed_gpio_free;
+	gpio->chip.get = aspeed_gpio_get;
+	gpio->chip.set = aspeed_gpio_set;
+	gpio->chip.set_config = aspeed_gpio_set_config;
+	gpio->chip.label = dev_name(&pdev->dev);
+	gpio->chip.base = -1;
+
+	/* Allocate a cache of the output registers */
+	banks = DIV_ROUND_UP(gpio->chip.ngpio, 32);
+	gpio->dcache = devm_kcalloc(&pdev->dev,
+				    banks, sizeof(u32), GFP_KERNEL);
+	if (!gpio->dcache)
+		return -ENOMEM;
+
+	/*
+	 * Populate it with initial values read from the HW and switch
+	 * all command sources to the ARM by default
+	 */
+	for (i = 0; i < banks; i++) {
+		const struct aspeed_gpio_bank *bank = &aspeed_gpio_banks[i];
+		void __iomem *addr = bank_reg(gpio, bank, reg_rdata);
+		gpio->dcache[i] = ioread32(addr);
+		aspeed_gpio_change_cmd_source(gpio, bank, 0, GPIO_CMDSRC_ARM);
+		aspeed_gpio_change_cmd_source(gpio, bank, 1, GPIO_CMDSRC_ARM);
+		aspeed_gpio_change_cmd_source(gpio, bank, 2, GPIO_CMDSRC_ARM);
+		aspeed_gpio_change_cmd_source(gpio, bank, 3, GPIO_CMDSRC_ARM);
+	}
+
+	/* Set up an irqchip */
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+	gpio->irq = irq;
+	girq = &gpio->chip.irq;
+	gpio_irq_chip_set_chip(girq, &aspeed_gpio_irq_chip);
+
+	girq->parent_handler = aspeed_gpio_irq_handler;
+	girq->num_parents = 1;
+	girq->parents = devm_kcalloc(&pdev->dev, 1, sizeof(*girq->parents), GFP_KERNEL);
+	if (!girq->parents)
+		return -ENOMEM;
+	girq->parents[0] = gpio->irq;
+	girq->default_type = IRQ_TYPE_NONE;
+	girq->handler = handle_bad_irq;
+	girq->init_valid_mask = aspeed_init_irq_valid_mask;
+
+	gpio->offset_timer =
+		devm_kzalloc(&pdev->dev, gpio->chip.ngpio, GFP_KERNEL);
+	if (!gpio->offset_timer)
+		return -ENOMEM;
+
+	rc = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
+	if (rc < 0)
+		return rc;
+
+	return 0;
+}
+
+static struct platform_driver aspeed_gpio_driver = {
+	.driver = {
+		.name = KBUILD_MODNAME,
+		.of_match_table = aspeed_gpio_of_table,
+	},
+};
+
+module_platform_driver_probe(aspeed_gpio_driver, aspeed_gpio_probe);
+
+MODULE_DESCRIPTION("Aspeed GPIO Driver");
+MODULE_LICENSE("GPL");