1 files changed, 422 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-intel-mid.c b/drivers/gpio/gpio-intel-mid.c
new file mode 100644
index 000000000..028d64c2c
--- /dev/null
+++ b/drivers/gpio/gpio-intel-mid.c
@@ -0,0 +1,422 @@
+/*
+ * Intel MID GPIO driver
+ *
+ * Copyright (c) 2008-2014,2016 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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.
+ */
+
+/* Supports:
+ * Moorestown platform Langwell chip.
+ * Medfield platform Penwell chip.
+ * Clovertrail platform Cloverview chip.
+ */
+
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/gpio/driver.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/stddef.h>
+
+#define INTEL_MID_IRQ_TYPE_EDGE		(1 << 0)
+#define INTEL_MID_IRQ_TYPE_LEVEL	(1 << 1)
+
+/*
+ * Langwell chip has 64 pins and thus there are 2 32bit registers to control
+ * each feature, while Penwell chip has 96 pins for each block, and need 3 32bit
+ * registers to control them, so we only define the order here instead of a
+ * structure, to get a bit offset for a pin (use GPDR as an example):
+ *
+ * nreg = ngpio / 32;
+ * reg = offset / 32;
+ * bit = offset % 32;
+ * reg_addr = reg_base + GPDR * nreg * 4 + reg * 4;
+ *
+ * so the bit of reg_addr is to control pin offset's GPDR feature
+*/
+
+enum GPIO_REG {
+	GPLR = 0,	/* pin level read-only */
+	GPDR,		/* pin direction */
+	GPSR,		/* pin set */
+	GPCR,		/* pin clear */
+	GRER,		/* rising edge detect */
+	GFER,		/* falling edge detect */
+	GEDR,		/* edge detect result */
+	GAFR,		/* alt function */
+};
+
+/* intel_mid gpio driver data */
+struct intel_mid_gpio_ddata {
+	u16 ngpio;		/* number of gpio pins */
+	u32 chip_irq_type;	/* chip interrupt type */
+};
+
+struct intel_mid_gpio {
+	struct gpio_chip		chip;
+	void __iomem			*reg_base;
+	spinlock_t			lock;
+	struct pci_dev			*pdev;
+};
+
+static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned offset,
+			      enum GPIO_REG reg_type)
+{
+	struct intel_mid_gpio *priv = gpiochip_get_data(chip);
+	unsigned nreg = chip->ngpio / 32;
+	u8 reg = offset / 32;
+
+	return priv->reg_base + reg_type * nreg * 4 + reg * 4;
+}
+
+static void __iomem *gpio_reg_2bit(struct gpio_chip *chip, unsigned offset,
+				   enum GPIO_REG reg_type)
+{
+	struct intel_mid_gpio *priv = gpiochip_get_data(chip);
+	unsigned nreg = chip->ngpio / 32;
+	u8 reg = offset / 16;
+
+	return priv->reg_base + reg_type * nreg * 4 + reg * 4;
+}
+
+static int intel_gpio_request(struct gpio_chip *chip, unsigned offset)
+{
+	void __iomem *gafr = gpio_reg_2bit(chip, offset, GAFR);
+	u32 value = readl(gafr);
+	int shift = (offset % 16) << 1, af = (value >> shift) & 3;
+
+	if (af) {
+		value &= ~(3 << shift);
+		writel(value, gafr);
+	}
+	return 0;
+}
+
+static int intel_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+	void __iomem *gplr = gpio_reg(chip, offset, GPLR);
+
+	return !!(readl(gplr) & BIT(offset % 32));
+}
+
+static void intel_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+	void __iomem *gpsr, *gpcr;
+
+	if (value) {
+		gpsr = gpio_reg(chip, offset, GPSR);
+		writel(BIT(offset % 32), gpsr);
+	} else {
+		gpcr = gpio_reg(chip, offset, GPCR);
+		writel(BIT(offset % 32), gpcr);
+	}
+}
+
+static int intel_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+	struct intel_mid_gpio *priv = gpiochip_get_data(chip);
+	void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
+	u32 value;
+	unsigned long flags;
+
+	if (priv->pdev)
+		pm_runtime_get(&priv->pdev->dev);
+
+	spin_lock_irqsave(&priv->lock, flags);
+	value = readl(gpdr);
+	value &= ~BIT(offset % 32);
+	writel(value, gpdr);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	if (priv->pdev)
+		pm_runtime_put(&priv->pdev->dev);
+
+	return 0;
+}
+
+static int intel_gpio_direction_output(struct gpio_chip *chip,
+			unsigned offset, int value)
+{
+	struct intel_mid_gpio *priv = gpiochip_get_data(chip);
+	void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
+	unsigned long flags;
+
+	intel_gpio_set(chip, offset, value);
+
+	if (priv->pdev)
+		pm_runtime_get(&priv->pdev->dev);
+
+	spin_lock_irqsave(&priv->lock, flags);
+	value = readl(gpdr);
+	value |= BIT(offset % 32);
+	writel(value, gpdr);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	if (priv->pdev)
+		pm_runtime_put(&priv->pdev->dev);
+
+	return 0;
+}
+
+static int intel_mid_irq_type(struct irq_data *d, unsigned type)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct intel_mid_gpio *priv = gpiochip_get_data(gc);
+	u32 gpio = irqd_to_hwirq(d);
+	unsigned long flags;
+	u32 value;
+	void __iomem *grer = gpio_reg(&priv->chip, gpio, GRER);
+	void __iomem *gfer = gpio_reg(&priv->chip, gpio, GFER);
+
+	if (gpio >= priv->chip.ngpio)
+		return -EINVAL;
+
+	if (priv->pdev)
+		pm_runtime_get(&priv->pdev->dev);
+
+	spin_lock_irqsave(&priv->lock, flags);
+	if (type & IRQ_TYPE_EDGE_RISING)
+		value = readl(grer) | BIT(gpio % 32);
+	else
+		value = readl(grer) & (~BIT(gpio % 32));
+	writel(value, grer);
+
+	if (type & IRQ_TYPE_EDGE_FALLING)
+		value = readl(gfer) | BIT(gpio % 32);
+	else
+		value = readl(gfer) & (~BIT(gpio % 32));
+	writel(value, gfer);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	if (priv->pdev)
+		pm_runtime_put(&priv->pdev->dev);
+
+	return 0;
+}
+
+static void intel_mid_irq_unmask(struct irq_data *d)
+{
+}
+
+static void intel_mid_irq_mask(struct irq_data *d)
+{
+}
+
+static struct irq_chip intel_mid_irqchip = {
+	.name		= "INTEL_MID-GPIO",
+	.irq_mask	= intel_mid_irq_mask,
+	.irq_unmask	= intel_mid_irq_unmask,
+	.irq_set_type	= intel_mid_irq_type,
+};
+
+static const struct intel_mid_gpio_ddata gpio_lincroft = {
+	.ngpio = 64,
+};
+
+static const struct intel_mid_gpio_ddata gpio_penwell_aon = {
+	.ngpio = 96,
+	.chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
+};
+
+static const struct intel_mid_gpio_ddata gpio_penwell_core = {
+	.ngpio = 96,
+	.chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
+};
+
+static const struct intel_mid_gpio_ddata gpio_cloverview_aon = {
+	.ngpio = 96,
+	.chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE | INTEL_MID_IRQ_TYPE_LEVEL,
+};
+
+static const struct intel_mid_gpio_ddata gpio_cloverview_core = {
+	.ngpio = 96,
+	.chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
+};
+
+static const struct pci_device_id intel_gpio_ids[] = {
+	{
+		/* Lincroft */
+		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f),
+		.driver_data = (kernel_ulong_t)&gpio_lincroft,
+	},
+	{
+		/* Penwell AON */
+		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081f),
+		.driver_data = (kernel_ulong_t)&gpio_penwell_aon,
+	},
+	{
+		/* Penwell Core */
+		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081a),
+		.driver_data = (kernel_ulong_t)&gpio_penwell_core,
+	},
+	{
+		/* Cloverview Aon */
+		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08eb),
+		.driver_data = (kernel_ulong_t)&gpio_cloverview_aon,
+	},
+	{
+		/* Cloverview Core */
+		PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08f7),
+		.driver_data = (kernel_ulong_t)&gpio_cloverview_core,
+	},
+	{ 0 }
+};
+MODULE_DEVICE_TABLE(pci, intel_gpio_ids);
+
+static void intel_mid_irq_handler(struct irq_desc *desc)
+{
+	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
+	struct intel_mid_gpio *priv = gpiochip_get_data(gc);
+	struct irq_data *data = irq_desc_get_irq_data(desc);
+	struct irq_chip *chip = irq_data_get_irq_chip(data);
+	u32 base, gpio, mask;
+	unsigned long pending;
+	void __iomem *gedr;
+
+	/* check GPIO controller to check which pin triggered the interrupt */
+	for (base = 0; base < priv->chip.ngpio; base += 32) {
+		gedr = gpio_reg(&priv->chip, base, GEDR);
+		while ((pending = readl(gedr))) {
+			gpio = __ffs(pending);
+			mask = BIT(gpio);
+			/* Clear before handling so we can't lose an edge */
+			writel(mask, gedr);
+			generic_handle_irq(irq_find_mapping(gc->irq.domain,
+							    base + gpio));
+		}
+	}
+
+	chip->irq_eoi(data);
+}
+
+static void intel_mid_irq_init_hw(struct intel_mid_gpio *priv)
+{
+	void __iomem *reg;
+	unsigned base;
+
+	for (base = 0; base < priv->chip.ngpio; base += 32) {
+		/* Clear the rising-edge detect register */
+		reg = gpio_reg(&priv->chip, base, GRER);
+		writel(0, reg);
+		/* Clear the falling-edge detect register */
+		reg = gpio_reg(&priv->chip, base, GFER);
+		writel(0, reg);
+		/* Clear the edge detect status register */
+		reg = gpio_reg(&priv->chip, base, GEDR);
+		writel(~0, reg);
+	}
+}
+
+static int __maybe_unused intel_gpio_runtime_idle(struct device *dev)
+{
+	int err = pm_schedule_suspend(dev, 500);
+	return err ?: -EBUSY;
+}
+
+static const struct dev_pm_ops intel_gpio_pm_ops = {
+	SET_RUNTIME_PM_OPS(NULL, NULL, intel_gpio_runtime_idle)
+};
+
+static int intel_gpio_probe(struct pci_dev *pdev,
+			  const struct pci_device_id *id)
+{
+	void __iomem *base;
+	struct intel_mid_gpio *priv;
+	u32 gpio_base;
+	u32 irq_base;
+	int retval;
+	struct intel_mid_gpio_ddata *ddata =
+				(struct intel_mid_gpio_ddata *)id->driver_data;
+
+	retval = pcim_enable_device(pdev);
+	if (retval)
+		return retval;
+
+	retval = pcim_iomap_regions(pdev, 1 << 0 | 1 << 1, pci_name(pdev));
+	if (retval) {
+		dev_err(&pdev->dev, "I/O memory mapping error\n");
+		return retval;
+	}
+
+	base = pcim_iomap_table(pdev)[1];
+
+	irq_base = readl(base);
+	gpio_base = readl(sizeof(u32) + base);
+
+	/* release the IO mapping, since we already get the info from bar1 */
+	pcim_iounmap_regions(pdev, 1 << 1);
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->reg_base = pcim_iomap_table(pdev)[0];
+	priv->chip.label = dev_name(&pdev->dev);
+	priv->chip.parent = &pdev->dev;
+	priv->chip.request = intel_gpio_request;
+	priv->chip.direction_input = intel_gpio_direction_input;
+	priv->chip.direction_output = intel_gpio_direction_output;
+	priv->chip.get = intel_gpio_get;
+	priv->chip.set = intel_gpio_set;
+	priv->chip.base = gpio_base;
+	priv->chip.ngpio = ddata->ngpio;
+	priv->chip.can_sleep = false;
+	priv->pdev = pdev;
+
+	spin_lock_init(&priv->lock);
+
+	pci_set_drvdata(pdev, priv);
+	retval = devm_gpiochip_add_data(&pdev->dev, &priv->chip, priv);
+	if (retval) {
+		dev_err(&pdev->dev, "gpiochip_add error %d\n", retval);
+		return retval;
+	}
+
+	retval = gpiochip_irqchip_add(&priv->chip,
+				      &intel_mid_irqchip,
+				      irq_base,
+				      handle_simple_irq,
+				      IRQ_TYPE_NONE);
+	if (retval) {
+		dev_err(&pdev->dev,
+			"could not connect irqchip to gpiochip\n");
+		return retval;
+	}
+
+	intel_mid_irq_init_hw(priv);
+
+	gpiochip_set_chained_irqchip(&priv->chip,
+				     &intel_mid_irqchip,
+				     pdev->irq,
+				     intel_mid_irq_handler);
+
+	pm_runtime_put_noidle(&pdev->dev);
+	pm_runtime_allow(&pdev->dev);
+
+	return 0;
+}
+
+static struct pci_driver intel_gpio_driver = {
+	.name		= "intel_mid_gpio",
+	.id_table	= intel_gpio_ids,
+	.probe		= intel_gpio_probe,
+	.driver		= {
+		.pm	= &intel_gpio_pm_ops,
+	},
+};
+
+builtin_pci_driver(intel_gpio_driver);