diff --git a/drivers/gpio/gpio-aspeed.c b/drivers/gpio/gpio-aspeed.c
index 20f6f8a..6e4b278 100644
--- a/drivers/gpio/gpio-aspeed.c
+++ b/drivers/gpio/gpio-aspeed.c
@@ -15,14 +15,27 @@
 #include <linux/io.h>
 #include <linux/spinlock.h>
 #include <linux/platform_device.h>
+#include <linux/gpio.h>
 #include <linux/gpio/driver.h>
 #include <linux/pinctrl/consumer.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;
+};
+
 struct aspeed_gpio {
 	struct gpio_chip chip;
 	spinlock_t lock;
 	void __iomem *base;
 	int irq;
+	const struct aspeed_gpio_config *config;
 };
 
 struct aspeed_gpio_bank {
@@ -62,11 +75,16 @@
 		.irq_regs = 0x0148,
 		.names = { "U", "V", "W", "X" },
 	},
-	/*
-	 * A bank exists for { 'Y', 'Z', "AA", "AB" }, but is not implemented.
-	 * Only half of GPIOs Y support interrupt configuration, and none of Z,
-	 * AA or AB do as they are output only.
-	 */
+	{
+		.val_regs = 0x01E0,
+		.irq_regs = 0x0178,
+		.names = { "Y", "Z", "AA", "AB" },
+	},
+	{
+		.val_regs = 0x01E8,
+		.irq_regs = 0x01A8,
+		.names = { "AC", "", "", "" },
+	},
 };
 
 #define GPIO_BANK(x)	((x) >> 5)
@@ -90,6 +108,51 @@
 	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))
+
+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 __iomem *bank_val_reg(struct aspeed_gpio *gpio,
 		const struct aspeed_gpio_bank *bank,
 		unsigned int reg)
@@ -152,6 +215,9 @@
 	unsigned long flags;
 	u32 reg;
 
+	if (!have_input(gpio, offset))
+		return -ENOTSUPP;
+
 	spin_lock_irqsave(&gpio->lock, flags);
 
 	reg = ioread32(bank_val_reg(gpio, bank, GPIO_DIR));
@@ -170,6 +236,9 @@
 	unsigned long flags;
 	u32 reg;
 
+	if (!have_output(gpio, offset))
+		return -ENOTSUPP;
+
 	spin_lock_irqsave(&gpio->lock, flags);
 
 	reg = ioread32(bank_val_reg(gpio, bank, GPIO_DIR));
@@ -189,6 +258,12 @@
 	unsigned long flags;
 	u32 val;
 
+	if (!have_input(gpio, offset))
+		return GPIOF_DIR_OUT;
+
+	if (!have_output(gpio, offset))
+		return GPIOF_DIR_IN;
+
 	spin_lock_irqsave(&gpio->lock, flags);
 
 	val = ioread32(bank_val_reg(gpio, bank, GPIO_DIR)) & GPIO_BIT(offset);
@@ -205,10 +280,17 @@
 		u32 *bit)
 {
 	int offset;
+	struct aspeed_gpio *internal;
 
 	offset = irqd_to_hwirq(d);
 
-	*gpio = irq_data_get_irq_chip_data(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);
 
@@ -364,6 +446,28 @@
 	.irq_set_type	= aspeed_gpio_set_type,
 };
 
+static void set_irq_valid_mask(struct aspeed_gpio *gpio)
+{
+	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->config->nr_gpios)
+				break;
+
+			clear_bit(i, gpio->chip.irq_valid_mask);
+		}
+
+		props++;
+	}
+}
+
 static int aspeed_gpio_setup_irqs(struct aspeed_gpio *gpio,
 		struct platform_device *pdev)
 {
@@ -375,6 +479,8 @@
 
 	gpio->irq = rc;
 
+	set_irq_valid_mask(gpio);
+
 	rc = gpiochip_irqchip_add(&gpio->chip, &aspeed_gpio_irqchip,
 			0, handle_bad_irq, IRQ_TYPE_NONE);
 	if (rc) {
@@ -390,6 +496,9 @@
 
 static int aspeed_gpio_request(struct gpio_chip *chip, unsigned int offset)
 {
+	if (!have_gpio(gpiochip_get_data(chip), offset))
+		return -ENODEV;
+
 	return pinctrl_request_gpio(chip->base + offset);
 }
 
@@ -398,8 +507,46 @@
 	pinctrl_free_gpio(chip->base + offset);
 }
 
+/*
+ * 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 of_device_id aspeed_gpio_of_table[] = {
+	{ .compatible = "aspeed,ast2400-gpio", .data = &ast2400_config, },
+	{ .compatible = "aspeed,ast2500-gpio", .data = &ast2500_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 aspeed_gpio *gpio;
 	struct resource *res;
 	int rc;
@@ -415,8 +562,13 @@
 
 	spin_lock_init(&gpio->lock);
 
-	gpio->chip.ngpio = ARRAY_SIZE(aspeed_gpio_banks) * 32;
+	gpio_id = of_match_node(aspeed_gpio_of_table, pdev->dev.of_node);
+	if (!gpio_id)
+		return -EINVAL;
 
+	gpio->config = gpio_id->data;
+
+	gpio->chip.ngpio = gpio->config->nr_gpios;
 	gpio->chip.parent = &pdev->dev;
 	gpio->chip.direction_input = aspeed_gpio_dir_in;
 	gpio->chip.direction_output = aspeed_gpio_dir_out;
@@ -427,6 +579,7 @@
 	gpio->chip.set = aspeed_gpio_set;
 	gpio->chip.label = dev_name(&pdev->dev);
 	gpio->chip.base = -1;
+	gpio->chip.irq_need_valid_mask = true;
 
 	rc = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
 	if (rc < 0)
@@ -435,13 +588,6 @@
 	return aspeed_gpio_setup_irqs(gpio, pdev);
 }
 
-static const struct of_device_id aspeed_gpio_of_table[] = {
-	{ .compatible = "aspeed,ast2400-gpio" },
-	{ .compatible = "aspeed,ast2500-gpio" },
-	{}
-};
-MODULE_DEVICE_TABLE(of, aspeed_gpio_of_table);
-
 static struct platform_driver aspeed_gpio_driver = {
 	.driver = {
 		.name = KBUILD_MODNAME,