pinctrl: Move Intel Baytrail pinctrl driver under intel directory

We are going to have more pinctrl drivers for Intel hardware so separate
all our pin controller drivers to own directory.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

3 files changed, 639 insertions, 0 deletions

diff --git a/drivers/pinctrl/intel/Kconfig b/drivers/pinctrl/intel/Kconfig
new file mode 100644
index 000000000000..957c90386307
--- /dev/null
+++ b/drivers/pinctrl/intel/Kconfig
@@ -0,0 +1,15 @@
+#
+# Intel pin control drivers
+#
+
+config PINCTRL_BAYTRAIL
+	bool "Intel Baytrail GPIO pin control"
+	depends on GPIOLIB && ACPI
+	select GPIOLIB_IRQCHIP
+	help
+	  driver for memory mapped GPIO functionality on Intel Baytrail
+	  platforms. Supports 3 banks with 102, 28 and 44 gpios.
+	  Most pins are usually muxed to some other functionality by firmware,
+	  so only a small amount is available for gpio use.
+
+	  Requires ACPI device enumeration code to set up a platform device.
diff --git a/drivers/pinctrl/intel/Makefile b/drivers/pinctrl/intel/Makefile
new file mode 100644
index 000000000000..d049b769e327
--- /dev/null
+++ b/drivers/pinctrl/intel/Makefile
@@ -0,0 +1,3 @@
+# Intel pin control drivers
+
+obj-$(CONFIG_PINCTRL_BAYTRAIL)		+= pinctrl-baytrail.o
diff --git a/drivers/pinctrl/intel/pinctrl-baytrail.c b/drivers/pinctrl/intel/pinctrl-baytrail.c
new file mode 100644
index 000000000000..3ece00164523
--- /dev/null
+++ b/drivers/pinctrl/intel/pinctrl-baytrail.c
@@ -0,0 +1,621 @@
+/*
+ * Pinctrl GPIO driver for Intel Baytrail
+ * Copyright (c) 2012-2013, Intel Corporation.
+ *
+ * Author: Mathias Nyman <mathias.nyman@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/bitops.h>
+#include <linux/interrupt.h>
+#include <linux/gpio.h>
+#include <linux/acpi.h>
+#include <linux/platform_device.h>
+#include <linux/seq_file.h>
+#include <linux/io.h>
+#include <linux/pm_runtime.h>
+#include <linux/pinctrl/pinctrl.h>
+
+/* memory mapped register offsets */
+#define BYT_CONF0_REG		0x000
+#define BYT_CONF1_REG		0x004
+#define BYT_VAL_REG		0x008
+#define BYT_DFT_REG		0x00c
+#define BYT_INT_STAT_REG	0x800
+
+/* BYT_CONF0_REG register bits */
+#define BYT_IODEN		BIT(31)
+#define BYT_DIRECT_IRQ_EN	BIT(27)
+#define BYT_TRIG_NEG		BIT(26)
+#define BYT_TRIG_POS		BIT(25)
+#define BYT_TRIG_LVL		BIT(24)
+#define BYT_PULL_STR_SHIFT	9
+#define BYT_PULL_STR_MASK	(3 << BYT_PULL_STR_SHIFT)
+#define BYT_PULL_STR_2K		(0 << BYT_PULL_STR_SHIFT)
+#define BYT_PULL_STR_10K	(1 << BYT_PULL_STR_SHIFT)
+#define BYT_PULL_STR_20K	(2 << BYT_PULL_STR_SHIFT)
+#define BYT_PULL_STR_40K	(3 << BYT_PULL_STR_SHIFT)
+#define BYT_PULL_ASSIGN_SHIFT	7
+#define BYT_PULL_ASSIGN_MASK	(3 << BYT_PULL_ASSIGN_SHIFT)
+#define BYT_PULL_ASSIGN_UP	(1 << BYT_PULL_ASSIGN_SHIFT)
+#define BYT_PULL_ASSIGN_DOWN	(2 << BYT_PULL_ASSIGN_SHIFT)
+#define BYT_PIN_MUX		0x07
+
+/* BYT_VAL_REG register bits */
+#define BYT_INPUT_EN		BIT(2)  /* 0: input enabled (active low)*/
+#define BYT_OUTPUT_EN		BIT(1)  /* 0: output enabled (active low)*/
+#define BYT_LEVEL		BIT(0)
+
+#define BYT_DIR_MASK		(BIT(1) | BIT(2))
+#define BYT_TRIG_MASK		(BIT(26) | BIT(25) | BIT(24))
+
+#define BYT_NGPIO_SCORE		102
+#define BYT_NGPIO_NCORE		28
+#define BYT_NGPIO_SUS		44
+
+#define BYT_SCORE_ACPI_UID	"1"
+#define BYT_NCORE_ACPI_UID	"2"
+#define BYT_SUS_ACPI_UID	"3"
+
+/*
+ * Baytrail gpio controller consist of three separate sub-controllers called
+ * SCORE, NCORE and SUS. The sub-controllers are identified by their acpi UID.
+ *
+ * GPIO numbering is _not_ ordered meaning that gpio # 0 in ACPI namespace does
+ * _not_ correspond to the first gpio register at controller's gpio base.
+ * There is no logic or pattern in mapping gpio numbers to registers (pads) so
+ * each sub-controller needs to have its own mapping table
+ */
+
+/* score_pins[gpio_nr] = pad_nr */
+
+static unsigned const score_pins[BYT_NGPIO_SCORE] = {
+	85, 89, 93, 96, 99, 102, 98, 101, 34, 37,
+	36, 38, 39, 35, 40, 84, 62, 61, 64, 59,
+	54, 56, 60, 55, 63, 57, 51, 50, 53, 47,
+	52, 49, 48, 43, 46, 41, 45, 42, 58, 44,
+	95, 105, 70, 68, 67, 66, 69, 71, 65, 72,
+	86, 90, 88, 92, 103, 77, 79, 83, 78, 81,
+	80, 82, 13, 12, 15, 14, 17, 18, 19, 16,
+	2, 1, 0, 4, 6, 7, 9, 8, 33, 32,
+	31, 30, 29, 27, 25, 28, 26, 23, 21, 20,
+	24, 22, 5, 3, 10, 11, 106, 87, 91, 104,
+	97, 100,
+};
+
+static unsigned const ncore_pins[BYT_NGPIO_NCORE] = {
+	19, 18, 17, 20, 21, 22, 24, 25, 23, 16,
+	14, 15, 12, 26, 27, 1, 4, 8, 11, 0,
+	3, 6, 10, 13, 2, 5, 9, 7,
+};
+
+static unsigned const sus_pins[BYT_NGPIO_SUS] = {
+	29, 33, 30, 31, 32, 34, 36, 35, 38, 37,
+	18, 7, 11, 20, 17, 1, 8, 10, 19, 12,
+	0, 2, 23, 39, 28, 27, 22, 21, 24, 25,
+	26, 51, 56, 54, 49, 55, 48, 57, 50, 58,
+	52, 53, 59, 40,
+};
+
+static struct pinctrl_gpio_range byt_ranges[] = {
+	{
+		.name = BYT_SCORE_ACPI_UID, /* match with acpi _UID in probe */
+		.npins = BYT_NGPIO_SCORE,
+		.pins = score_pins,
+	},
+	{
+		.name = BYT_NCORE_ACPI_UID,
+		.npins = BYT_NGPIO_NCORE,
+		.pins = ncore_pins,
+	},
+	{
+		.name = BYT_SUS_ACPI_UID,
+		.npins = BYT_NGPIO_SUS,
+		.pins = sus_pins,
+	},
+	{
+	},
+};
+
+struct byt_gpio {
+	struct gpio_chip		chip;
+	struct platform_device		*pdev;
+	spinlock_t			lock;
+	void __iomem			*reg_base;
+	struct pinctrl_gpio_range	*range;
+};
+
+#define to_byt_gpio(c)	container_of(c, struct byt_gpio, chip)
+
+static void __iomem *byt_gpio_reg(struct gpio_chip *chip, unsigned offset,
+				 int reg)
+{
+	struct byt_gpio *vg = to_byt_gpio(chip);
+	u32 reg_offset;
+
+	if (reg == BYT_INT_STAT_REG)
+		reg_offset = (offset / 32) * 4;
+	else
+		reg_offset = vg->range->pins[offset] * 16;
+
+	return vg->reg_base + reg_offset + reg;
+}
+
+static bool is_special_pin(struct byt_gpio *vg, unsigned offset)
+{
+	/* SCORE pin 92-93 */
+	if (!strcmp(vg->range->name, BYT_SCORE_ACPI_UID) &&
+		offset >= 92 && offset <= 93)
+		return true;
+
+	/* SUS pin 11-21 */
+	if (!strcmp(vg->range->name, BYT_SUS_ACPI_UID) &&
+		offset >= 11 && offset <= 21)
+		return true;
+
+	return false;
+}
+
+static int byt_gpio_request(struct gpio_chip *chip, unsigned offset)
+{
+	struct byt_gpio *vg = to_byt_gpio(chip);
+	void __iomem *reg = byt_gpio_reg(chip, offset, BYT_CONF0_REG);
+	u32 value;
+	bool special;
+
+	/*
+	 * In most cases, func pin mux 000 means GPIO function.
+	 * But, some pins may have func pin mux 001 represents
+	 * GPIO function. Only allow user to export pin with
+	 * func pin mux preset as GPIO function by BIOS/FW.
+	 */
+	value = readl(reg) & BYT_PIN_MUX;
+	special = is_special_pin(vg, offset);
+	if ((special && value != 1) || (!special && value)) {
+		dev_err(&vg->pdev->dev,
+			"pin %u cannot be used as GPIO.\n", offset);
+		return -EINVAL;
+	}
+
+	pm_runtime_get(&vg->pdev->dev);
+
+	return 0;
+}
+
+static void byt_gpio_free(struct gpio_chip *chip, unsigned offset)
+{
+	struct byt_gpio *vg = to_byt_gpio(chip);
+	void __iomem *reg = byt_gpio_reg(&vg->chip, offset, BYT_CONF0_REG);
+	u32 value;
+
+	/* clear interrupt triggering */
+	value = readl(reg);
+	value &= ~(BYT_TRIG_POS | BYT_TRIG_NEG | BYT_TRIG_LVL);
+	writel(value, reg);
+
+	pm_runtime_put(&vg->pdev->dev);
+}
+
+static int byt_irq_type(struct irq_data *d, unsigned type)
+{
+	struct byt_gpio *vg = to_byt_gpio(irq_data_get_irq_chip_data(d));
+	u32 offset = irqd_to_hwirq(d);
+	u32 value;
+	unsigned long flags;
+	void __iomem *reg = byt_gpio_reg(&vg->chip, offset, BYT_CONF0_REG);
+
+	if (offset >= vg->chip.ngpio)
+		return -EINVAL;
+
+	spin_lock_irqsave(&vg->lock, flags);
+	value = readl(reg);
+
+	/* For level trigges the BYT_TRIG_POS and BYT_TRIG_NEG bits
+	 * are used to indicate high and low level triggering
+	 */
+	value &= ~(BYT_TRIG_POS | BYT_TRIG_NEG | BYT_TRIG_LVL);
+
+	switch (type) {
+	case IRQ_TYPE_LEVEL_HIGH:
+		value |= BYT_TRIG_LVL;
+	case IRQ_TYPE_EDGE_RISING:
+		value |= BYT_TRIG_POS;
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+		value |= BYT_TRIG_LVL;
+	case IRQ_TYPE_EDGE_FALLING:
+		value |= BYT_TRIG_NEG;
+		break;
+	case IRQ_TYPE_EDGE_BOTH:
+		value |= (BYT_TRIG_NEG | BYT_TRIG_POS);
+		break;
+	}
+	writel(value, reg);
+
+	spin_unlock_irqrestore(&vg->lock, flags);
+
+	return 0;
+}
+
+static int byt_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+	void __iomem *reg = byt_gpio_reg(chip, offset, BYT_VAL_REG);
+	return readl(reg) & BYT_LEVEL;
+}
+
+static void byt_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+	struct byt_gpio *vg = to_byt_gpio(chip);
+	void __iomem *reg = byt_gpio_reg(chip, offset, BYT_VAL_REG);
+	unsigned long flags;
+	u32 old_val;
+
+	spin_lock_irqsave(&vg->lock, flags);
+
+	old_val = readl(reg);
+
+	if (value)
+		writel(old_val | BYT_LEVEL, reg);
+	else
+		writel(old_val & ~BYT_LEVEL, reg);
+
+	spin_unlock_irqrestore(&vg->lock, flags);
+}
+
+static int byt_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+	struct byt_gpio *vg = to_byt_gpio(chip);
+	void __iomem *reg = byt_gpio_reg(chip, offset, BYT_VAL_REG);
+	unsigned long flags;
+	u32 value;
+
+	spin_lock_irqsave(&vg->lock, flags);
+
+	value = readl(reg) | BYT_DIR_MASK;
+	value &= ~BYT_INPUT_EN;		/* active low */
+	writel(value, reg);
+
+	spin_unlock_irqrestore(&vg->lock, flags);
+
+	return 0;
+}
+
+static int byt_gpio_direction_output(struct gpio_chip *chip,
+				     unsigned gpio, int value)
+{
+	struct byt_gpio *vg = to_byt_gpio(chip);
+	void __iomem *conf_reg = byt_gpio_reg(chip, gpio, BYT_CONF0_REG);
+	void __iomem *reg = byt_gpio_reg(chip, gpio, BYT_VAL_REG);
+	unsigned long flags;
+	u32 reg_val;
+
+	spin_lock_irqsave(&vg->lock, flags);
+
+	/*
+	 * Before making any direction modifications, do a check if gpio
+	 * is set for direct IRQ.  On baytrail, setting GPIO to output does
+	 * not make sense, so let's at least warn the caller before they shoot
+	 * themselves in the foot.
+	 */
+	WARN(readl(conf_reg) & BYT_DIRECT_IRQ_EN,
+		"Potential Error: Setting GPIO with direct_irq_en to output");
+
+	reg_val = readl(reg) | BYT_DIR_MASK;
+	reg_val &= ~BYT_OUTPUT_EN;
+
+	if (value)
+		writel(reg_val | BYT_LEVEL, reg);
+	else
+		writel(reg_val & ~BYT_LEVEL, reg);
+
+	spin_unlock_irqrestore(&vg->lock, flags);
+
+	return 0;
+}
+
+static void byt_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
+{
+	struct byt_gpio *vg = to_byt_gpio(chip);
+	int i;
+	unsigned long flags;
+	u32 conf0, val, offs;
+
+	spin_lock_irqsave(&vg->lock, flags);
+
+	for (i = 0; i < vg->chip.ngpio; i++) {
+		const char *pull_str = NULL;
+		const char *pull = NULL;
+		const char *label;
+		offs = vg->range->pins[i] * 16;
+		conf0 = readl(vg->reg_base + offs + BYT_CONF0_REG);
+		val = readl(vg->reg_base + offs + BYT_VAL_REG);
+
+		label = gpiochip_is_requested(chip, i);
+		if (!label)
+			label = "Unrequested";
+
+		switch (conf0 & BYT_PULL_ASSIGN_MASK) {
+		case BYT_PULL_ASSIGN_UP:
+			pull = "up";
+			break;
+		case BYT_PULL_ASSIGN_DOWN:
+			pull = "down";
+			break;
+		}
+
+		switch (conf0 & BYT_PULL_STR_MASK) {
+		case BYT_PULL_STR_2K:
+			pull_str = "2k";
+			break;
+		case BYT_PULL_STR_10K:
+			pull_str = "10k";
+			break;
+		case BYT_PULL_STR_20K:
+			pull_str = "20k";
+			break;
+		case BYT_PULL_STR_40K:
+			pull_str = "40k";
+			break;
+		}
+
+		seq_printf(s,
+			   " gpio-%-3d (%-20.20s) %s %s %s pad-%-3d offset:0x%03x mux:%d %s%s%s",
+			   i,
+			   label,
+			   val & BYT_INPUT_EN ? "  " : "in",
+			   val & BYT_OUTPUT_EN ? "   " : "out",
+			   val & BYT_LEVEL ? "hi" : "lo",
+			   vg->range->pins[i], offs,
+			   conf0 & 0x7,
+			   conf0 & BYT_TRIG_NEG ? " fall" : "     ",
+			   conf0 & BYT_TRIG_POS ? " rise" : "     ",
+			   conf0 & BYT_TRIG_LVL ? " level" : "      ");
+
+		if (pull && pull_str)
+			seq_printf(s, " %-4s %-3s", pull, pull_str);
+		else
+			seq_puts(s, "          ");
+
+		if (conf0 & BYT_IODEN)
+			seq_puts(s, " open-drain");
+
+		seq_puts(s, "\n");
+	}
+	spin_unlock_irqrestore(&vg->lock, flags);
+}
+
+static void byt_gpio_irq_handler(unsigned irq, struct irq_desc *desc)
+{
+	struct irq_data *data = irq_desc_get_irq_data(desc);
+	struct byt_gpio *vg = to_byt_gpio(irq_desc_get_handler_data(desc));
+	struct irq_chip *chip = irq_data_get_irq_chip(data);
+	u32 base, pin, mask;
+	void __iomem *reg;
+	u32 pending;
+	unsigned virq;
+	int looplimit = 0;
+
+	/* check from GPIO controller which pin triggered the interrupt */
+	for (base = 0; base < vg->chip.ngpio; base += 32) {
+
+		reg = byt_gpio_reg(&vg->chip, base, BYT_INT_STAT_REG);
+
+		while ((pending = readl(reg))) {
+			pin = __ffs(pending);
+			mask = BIT(pin);
+			/* Clear before handling so we can't lose an edge */
+			writel(mask, reg);
+
+			virq = irq_find_mapping(vg->chip.irqdomain, base + pin);
+			generic_handle_irq(virq);
+
+			/* In case bios or user sets triggering incorretly a pin
+			 * might remain in "interrupt triggered" state.
+			 */
+			if (looplimit++ > 32) {
+				dev_err(&vg->pdev->dev,
+					"Gpio %d interrupt flood, disabling\n",
+					base + pin);
+
+				reg = byt_gpio_reg(&vg->chip, base + pin,
+						   BYT_CONF0_REG);
+				mask = readl(reg);
+				mask &= ~(BYT_TRIG_NEG | BYT_TRIG_POS |
+					  BYT_TRIG_LVL);
+				writel(mask, reg);
+				mask = readl(reg); /* flush */
+				break;
+			}
+		}
+	}
+	chip->irq_eoi(data);
+}
+
+static void byt_irq_unmask(struct irq_data *d)
+{
+}
+
+static void byt_irq_mask(struct irq_data *d)
+{
+}
+
+static struct irq_chip byt_irqchip = {
+	.name = "BYT-GPIO",
+	.irq_mask = byt_irq_mask,
+	.irq_unmask = byt_irq_unmask,
+	.irq_set_type = byt_irq_type,
+	.flags = IRQCHIP_SKIP_SET_WAKE,
+};
+
+static void byt_gpio_irq_init_hw(struct byt_gpio *vg)
+{
+	void __iomem *reg;
+	u32 base, value;
+
+	/* clear interrupt status trigger registers */
+	for (base = 0; base < vg->chip.ngpio; base += 32) {
+		reg = byt_gpio_reg(&vg->chip, base, BYT_INT_STAT_REG);
+		writel(0xffffffff, reg);
+		/* make sure trigger bits are cleared, if not then a pin
+		   might be misconfigured in bios */
+		value = readl(reg);
+		if (value)
+			dev_err(&vg->pdev->dev,
+				"GPIO interrupt error, pins misconfigured\n");
+	}
+}
+
+static int byt_gpio_probe(struct platform_device *pdev)
+{
+	struct byt_gpio *vg;
+	struct gpio_chip *gc;
+	struct resource *mem_rc, *irq_rc;
+	struct device *dev = &pdev->dev;
+	struct acpi_device *acpi_dev;
+	struct pinctrl_gpio_range *range;
+	acpi_handle handle = ACPI_HANDLE(dev);
+	int ret;
+
+	if (acpi_bus_get_device(handle, &acpi_dev))
+		return -ENODEV;
+
+	vg = devm_kzalloc(dev, sizeof(struct byt_gpio), GFP_KERNEL);
+	if (!vg) {
+		dev_err(&pdev->dev, "can't allocate byt_gpio chip data\n");
+		return -ENOMEM;
+	}
+
+	for (range = byt_ranges; range->name; range++) {
+		if (!strcmp(acpi_dev->pnp.unique_id, range->name)) {
+			vg->chip.ngpio = range->npins;
+			vg->range = range;
+			break;
+		}
+	}
+
+	if (!vg->chip.ngpio || !vg->range)
+		return -ENODEV;
+
+	vg->pdev = pdev;
+	platform_set_drvdata(pdev, vg);
+
+	mem_rc = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	vg->reg_base = devm_ioremap_resource(dev, mem_rc);
+	if (IS_ERR(vg->reg_base))
+		return PTR_ERR(vg->reg_base);
+
+	spin_lock_init(&vg->lock);
+
+	gc = &vg->chip;
+	gc->label = dev_name(&pdev->dev);
+	gc->owner = THIS_MODULE;
+	gc->request = byt_gpio_request;
+	gc->free = byt_gpio_free;
+	gc->direction_input = byt_gpio_direction_input;
+	gc->direction_output = byt_gpio_direction_output;
+	gc->get = byt_gpio_get;
+	gc->set = byt_gpio_set;
+	gc->dbg_show = byt_gpio_dbg_show;
+	gc->base = -1;
+	gc->can_sleep = false;
+	gc->dev = dev;
+
+	ret = gpiochip_add(gc);
+	if (ret) {
+		dev_err(&pdev->dev, "failed adding byt-gpio chip\n");
+		return ret;
+	}
+
+	/* set up interrupts  */
+	irq_rc = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (irq_rc && irq_rc->start) {
+		byt_gpio_irq_init_hw(vg);
+		ret = gpiochip_irqchip_add(gc, &byt_irqchip, 0,
+					   handle_simple_irq, IRQ_TYPE_NONE);
+		if (ret) {
+			dev_err(dev, "failed to add irqchip\n");
+			gpiochip_remove(gc);
+			return ret;
+		}
+
+		gpiochip_set_chained_irqchip(gc, &byt_irqchip,
+					     (unsigned)irq_rc->start,
+					     byt_gpio_irq_handler);
+	}
+
+	pm_runtime_enable(dev);
+
+	return 0;
+}
+
+static int byt_gpio_runtime_suspend(struct device *dev)
+{
+	return 0;
+}
+
+static int byt_gpio_runtime_resume(struct device *dev)
+{
+	return 0;
+}
+
+static const struct dev_pm_ops byt_gpio_pm_ops = {
+	.runtime_suspend = byt_gpio_runtime_suspend,
+	.runtime_resume = byt_gpio_runtime_resume,
+};
+
+static const struct acpi_device_id byt_gpio_acpi_match[] = {
+	{ "INT33B2", 0 },
+	{ "INT33FC", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, byt_gpio_acpi_match);
+
+static int byt_gpio_remove(struct platform_device *pdev)
+{
+	struct byt_gpio *vg = platform_get_drvdata(pdev);
+
+	pm_runtime_disable(&pdev->dev);
+	gpiochip_remove(&vg->chip);
+
+	return 0;
+}
+
+static struct platform_driver byt_gpio_driver = {
+	.probe          = byt_gpio_probe,
+	.remove         = byt_gpio_remove,
+	.driver         = {
+		.name   = "byt_gpio",
+		.owner  = THIS_MODULE,
+		.pm	= &byt_gpio_pm_ops,
+		.acpi_match_table = ACPI_PTR(byt_gpio_acpi_match),
+	},
+};
+
+static int __init byt_gpio_init(void)
+{
+	return platform_driver_register(&byt_gpio_driver);
+}
+subsys_initcall(byt_gpio_init);
+
+static void __exit byt_gpio_exit(void)
+{
+	platform_driver_unregister(&byt_gpio_driver);
+}
+module_exit(byt_gpio_exit);