1 files changed, 465 insertions, 0 deletions

diff --git a/drivers/gpio/gpio-ep93xx.c b/drivers/gpio/gpio-ep93xx.c
new file mode 100644
index 000000000..94d9fa0d6
--- /dev/null
+++ b/drivers/gpio/gpio-ep93xx.c
@@ -0,0 +1,465 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Generic EP93xx GPIO handling
+ *
+ * Copyright (c) 2008 Ryan Mallon
+ * Copyright (c) 2011 H Hartley Sweeten <hsweeten@visionengravers.com>
+ *
+ * Based on code originally from:
+ *  linux/arch/arm/mach-ep93xx/core.c
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+#include <linux/gpio/driver.h>
+#include <linux/bitops.h>
+
+#define EP93XX_GPIO_F_INT_STATUS 0x5c
+#define EP93XX_GPIO_A_INT_STATUS 0xa0
+#define EP93XX_GPIO_B_INT_STATUS 0xbc
+
+/* Maximum value for gpio line identifiers */
+#define EP93XX_GPIO_LINE_MAX 63
+
+/* Number of GPIO chips in EP93XX */
+#define EP93XX_GPIO_CHIP_NUM 8
+
+/* Maximum value for irq capable line identifiers */
+#define EP93XX_GPIO_LINE_MAX_IRQ 23
+
+/*
+ * Static mapping of GPIO bank F IRQS:
+ * F0..F7 (16..24) to irq 80..87.
+ */
+#define EP93XX_GPIO_F_IRQ_BASE 80
+
+struct ep93xx_gpio_irq_chip {
+	struct irq_chip ic;
+	u8 irq_offset;
+	u8 int_unmasked;
+	u8 int_enabled;
+	u8 int_type1;
+	u8 int_type2;
+	u8 int_debounce;
+};
+
+struct ep93xx_gpio_chip {
+	struct gpio_chip		gc;
+	struct ep93xx_gpio_irq_chip	*eic;
+};
+
+struct ep93xx_gpio {
+	void __iomem		*base;
+	struct ep93xx_gpio_chip	gc[EP93XX_GPIO_CHIP_NUM];
+};
+
+#define to_ep93xx_gpio_chip(x) container_of(x, struct ep93xx_gpio_chip, gc)
+
+static struct ep93xx_gpio_irq_chip *to_ep93xx_gpio_irq_chip(struct gpio_chip *gc)
+{
+	struct ep93xx_gpio_chip *egc = to_ep93xx_gpio_chip(gc);
+
+	return egc->eic;
+}
+
+/*************************************************************************
+ * Interrupt handling for EP93xx on-chip GPIOs
+ *************************************************************************/
+#define EP93XX_INT_TYPE1_OFFSET		0x00
+#define EP93XX_INT_TYPE2_OFFSET		0x04
+#define EP93XX_INT_EOI_OFFSET		0x08
+#define EP93XX_INT_EN_OFFSET		0x0c
+#define EP93XX_INT_STATUS_OFFSET	0x10
+#define EP93XX_INT_RAW_STATUS_OFFSET	0x14
+#define EP93XX_INT_DEBOUNCE_OFFSET	0x18
+
+static void ep93xx_gpio_update_int_params(struct ep93xx_gpio *epg,
+					  struct ep93xx_gpio_irq_chip *eic)
+{
+	writeb_relaxed(0, epg->base + eic->irq_offset + EP93XX_INT_EN_OFFSET);
+
+	writeb_relaxed(eic->int_type2,
+		       epg->base + eic->irq_offset + EP93XX_INT_TYPE2_OFFSET);
+
+	writeb_relaxed(eic->int_type1,
+		       epg->base + eic->irq_offset + EP93XX_INT_TYPE1_OFFSET);
+
+	writeb_relaxed(eic->int_unmasked & eic->int_enabled,
+		       epg->base + eic->irq_offset + EP93XX_INT_EN_OFFSET);
+}
+
+static void ep93xx_gpio_int_debounce(struct gpio_chip *gc,
+				     unsigned int offset, bool enable)
+{
+	struct ep93xx_gpio *epg = gpiochip_get_data(gc);
+	struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
+	int port_mask = BIT(offset);
+
+	if (enable)
+		eic->int_debounce |= port_mask;
+	else
+		eic->int_debounce &= ~port_mask;
+
+	writeb(eic->int_debounce,
+	       epg->base + eic->irq_offset + EP93XX_INT_DEBOUNCE_OFFSET);
+}
+
+static void ep93xx_gpio_ab_irq_handler(struct irq_desc *desc)
+{
+	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
+	struct ep93xx_gpio *epg = gpiochip_get_data(gc);
+	struct irq_chip *irqchip = irq_desc_get_chip(desc);
+	unsigned long stat;
+	int offset;
+
+	chained_irq_enter(irqchip, desc);
+
+	/*
+	 * Dispatch the IRQs to the irqdomain of each A and B
+	 * gpiochip irqdomains depending on what has fired.
+	 * The tricky part is that the IRQ line is shared
+	 * between bank A and B and each has their own gpiochip.
+	 */
+	stat = readb(epg->base + EP93XX_GPIO_A_INT_STATUS);
+	for_each_set_bit(offset, &stat, 8)
+		generic_handle_irq(irq_find_mapping(epg->gc[0].gc.irq.domain,
+						    offset));
+
+	stat = readb(epg->base + EP93XX_GPIO_B_INT_STATUS);
+	for_each_set_bit(offset, &stat, 8)
+		generic_handle_irq(irq_find_mapping(epg->gc[1].gc.irq.domain,
+						    offset));
+
+	chained_irq_exit(irqchip, desc);
+}
+
+static void ep93xx_gpio_f_irq_handler(struct irq_desc *desc)
+{
+	/*
+	 * map discontiguous hw irq range to continuous sw irq range:
+	 *
+	 *  IRQ_EP93XX_GPIO{0..7}MUX -> EP93XX_GPIO_LINE_F{0..7}
+	 */
+	struct irq_chip *irqchip = irq_desc_get_chip(desc);
+	unsigned int irq = irq_desc_get_irq(desc);
+	int port_f_idx = ((irq + 1) & 7) ^ 4; /* {19..22,47..50} -> {0..7} */
+	int gpio_irq = EP93XX_GPIO_F_IRQ_BASE + port_f_idx;
+
+	chained_irq_enter(irqchip, desc);
+	generic_handle_irq(gpio_irq);
+	chained_irq_exit(irqchip, desc);
+}
+
+static void ep93xx_gpio_irq_ack(struct irq_data *d)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
+	struct ep93xx_gpio *epg = gpiochip_get_data(gc);
+	int port_mask = BIT(d->irq & 7);
+
+	if (irqd_get_trigger_type(d) == IRQ_TYPE_EDGE_BOTH) {
+		eic->int_type2 ^= port_mask; /* switch edge direction */
+		ep93xx_gpio_update_int_params(epg, eic);
+	}
+
+	writeb(port_mask, epg->base + eic->irq_offset + EP93XX_INT_EOI_OFFSET);
+}
+
+static void ep93xx_gpio_irq_mask_ack(struct irq_data *d)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
+	struct ep93xx_gpio *epg = gpiochip_get_data(gc);
+	int port_mask = BIT(d->irq & 7);
+
+	if (irqd_get_trigger_type(d) == IRQ_TYPE_EDGE_BOTH)
+		eic->int_type2 ^= port_mask; /* switch edge direction */
+
+	eic->int_unmasked &= ~port_mask;
+	ep93xx_gpio_update_int_params(epg, eic);
+
+	writeb(port_mask, epg->base + eic->irq_offset + EP93XX_INT_EOI_OFFSET);
+}
+
+static void ep93xx_gpio_irq_mask(struct irq_data *d)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
+	struct ep93xx_gpio *epg = gpiochip_get_data(gc);
+
+	eic->int_unmasked &= ~BIT(d->irq & 7);
+	ep93xx_gpio_update_int_params(epg, eic);
+}
+
+static void ep93xx_gpio_irq_unmask(struct irq_data *d)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
+	struct ep93xx_gpio *epg = gpiochip_get_data(gc);
+
+	eic->int_unmasked |= BIT(d->irq & 7);
+	ep93xx_gpio_update_int_params(epg, eic);
+}
+
+/*
+ * gpio_int_type1 controls whether the interrupt is level (0) or
+ * edge (1) triggered, while gpio_int_type2 controls whether it
+ * triggers on low/falling (0) or high/rising (1).
+ */
+static int ep93xx_gpio_irq_type(struct irq_data *d, unsigned int type)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
+	struct ep93xx_gpio *epg = gpiochip_get_data(gc);
+	int offset = d->irq & 7;
+	int port_mask = BIT(offset);
+	irq_flow_handler_t handler;
+
+	gc->direction_input(gc, offset);
+
+	switch (type) {
+	case IRQ_TYPE_EDGE_RISING:
+		eic->int_type1 |= port_mask;
+		eic->int_type2 |= port_mask;
+		handler = handle_edge_irq;
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		eic->int_type1 |= port_mask;
+		eic->int_type2 &= ~port_mask;
+		handler = handle_edge_irq;
+		break;
+	case IRQ_TYPE_LEVEL_HIGH:
+		eic->int_type1 &= ~port_mask;
+		eic->int_type2 |= port_mask;
+		handler = handle_level_irq;
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+		eic->int_type1 &= ~port_mask;
+		eic->int_type2 &= ~port_mask;
+		handler = handle_level_irq;
+		break;
+	case IRQ_TYPE_EDGE_BOTH:
+		eic->int_type1 |= port_mask;
+		/* set initial polarity based on current input level */
+		if (gc->get(gc, offset))
+			eic->int_type2 &= ~port_mask; /* falling */
+		else
+			eic->int_type2 |= port_mask; /* rising */
+		handler = handle_edge_irq;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	irq_set_handler_locked(d, handler);
+
+	eic->int_enabled |= port_mask;
+
+	ep93xx_gpio_update_int_params(epg, eic);
+
+	return 0;
+}
+
+/*************************************************************************
+ * gpiolib interface for EP93xx on-chip GPIOs
+ *************************************************************************/
+struct ep93xx_gpio_bank {
+	const char	*label;
+	int		data;
+	int		dir;
+	int		irq;
+	int		base;
+	bool		has_irq;
+	bool		has_hierarchical_irq;
+	unsigned int	irq_base;
+};
+
+#define EP93XX_GPIO_BANK(_label, _data, _dir, _irq, _base, _has_irq, _has_hier, _irq_base) \
+	{							\
+		.label		= _label,			\
+		.data		= _data,			\
+		.dir		= _dir,				\
+		.irq		= _irq,				\
+		.base		= _base,			\
+		.has_irq	= _has_irq,			\
+		.has_hierarchical_irq = _has_hier,		\
+		.irq_base	= _irq_base,			\
+	}
+
+static struct ep93xx_gpio_bank ep93xx_gpio_banks[] = {
+	/* Bank A has 8 IRQs */
+	EP93XX_GPIO_BANK("A", 0x00, 0x10, 0x90, 0, true, false, 64),
+	/* Bank B has 8 IRQs */
+	EP93XX_GPIO_BANK("B", 0x04, 0x14, 0xac, 8, true, false, 72),
+	EP93XX_GPIO_BANK("C", 0x08, 0x18, 0x00, 40, false, false, 0),
+	EP93XX_GPIO_BANK("D", 0x0c, 0x1c, 0x00, 24, false, false, 0),
+	EP93XX_GPIO_BANK("E", 0x20, 0x24, 0x00, 32, false, false, 0),
+	/* Bank F has 8 IRQs */
+	EP93XX_GPIO_BANK("F", 0x30, 0x34, 0x4c, 16, false, true, 0),
+	EP93XX_GPIO_BANK("G", 0x38, 0x3c, 0x00, 48, false, false, 0),
+	EP93XX_GPIO_BANK("H", 0x40, 0x44, 0x00, 56, false, false, 0),
+};
+
+static int ep93xx_gpio_set_config(struct gpio_chip *gc, unsigned offset,
+				  unsigned long config)
+{
+	u32 debounce;
+
+	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
+		return -ENOTSUPP;
+
+	debounce = pinconf_to_config_argument(config);
+	ep93xx_gpio_int_debounce(gc, offset, debounce ? true : false);
+
+	return 0;
+}
+
+static int ep93xx_gpio_f_to_irq(struct gpio_chip *gc, unsigned offset)
+{
+	return EP93XX_GPIO_F_IRQ_BASE + offset;
+}
+
+static void ep93xx_init_irq_chip(struct device *dev, struct irq_chip *ic)
+{
+	ic->irq_ack = ep93xx_gpio_irq_ack;
+	ic->irq_mask_ack = ep93xx_gpio_irq_mask_ack;
+	ic->irq_mask = ep93xx_gpio_irq_mask;
+	ic->irq_unmask = ep93xx_gpio_irq_unmask;
+	ic->irq_set_type = ep93xx_gpio_irq_type;
+}
+
+static int ep93xx_gpio_add_bank(struct ep93xx_gpio_chip *egc,
+				struct platform_device *pdev,
+				struct ep93xx_gpio *epg,
+				struct ep93xx_gpio_bank *bank)
+{
+	void __iomem *data = epg->base + bank->data;
+	void __iomem *dir = epg->base + bank->dir;
+	struct gpio_chip *gc = &egc->gc;
+	struct device *dev = &pdev->dev;
+	struct gpio_irq_chip *girq;
+	int err;
+
+	err = bgpio_init(gc, dev, 1, data, NULL, NULL, dir, NULL, 0);
+	if (err)
+		return err;
+
+	gc->label = bank->label;
+	gc->base = bank->base;
+
+	girq = &gc->irq;
+	if (bank->has_irq || bank->has_hierarchical_irq) {
+		struct irq_chip *ic;
+
+		gc->set_config = ep93xx_gpio_set_config;
+		egc->eic = devm_kcalloc(dev, 1,
+					sizeof(*egc->eic),
+					GFP_KERNEL);
+		if (!egc->eic)
+			return -ENOMEM;
+		egc->eic->irq_offset = bank->irq;
+		ic = &egc->eic->ic;
+		ic->name = devm_kasprintf(dev, GFP_KERNEL, "gpio-irq-%s", bank->label);
+		if (!ic->name)
+			return -ENOMEM;
+		ep93xx_init_irq_chip(dev, ic);
+		girq->chip = ic;
+	}
+
+	if (bank->has_irq) {
+		int ab_parent_irq = platform_get_irq(pdev, 0);
+
+		girq->parent_handler = ep93xx_gpio_ab_irq_handler;
+		girq->num_parents = 1;
+		girq->parents = devm_kcalloc(dev, 1,
+					     sizeof(*girq->parents),
+					     GFP_KERNEL);
+		if (!girq->parents)
+			return -ENOMEM;
+		girq->default_type = IRQ_TYPE_NONE;
+		girq->handler = handle_level_irq;
+		girq->parents[0] = ab_parent_irq;
+		girq->first = bank->irq_base;
+	}
+
+	/* Only bank F has especially funky IRQ handling */
+	if (bank->has_hierarchical_irq) {
+		int gpio_irq;
+		int i;
+
+		/*
+		 * FIXME: convert this to use hierarchical IRQ support!
+		 * this requires fixing the root irqchip to be hierarchial.
+		 */
+		girq->parent_handler = ep93xx_gpio_f_irq_handler;
+		girq->num_parents = 8;
+		girq->parents = devm_kcalloc(dev, 8,
+					     sizeof(*girq->parents),
+					     GFP_KERNEL);
+		if (!girq->parents)
+			return -ENOMEM;
+		/* Pick resources 1..8 for these IRQs */
+		for (i = 1; i <= 8; i++)
+			girq->parents[i - 1] = platform_get_irq(pdev, i);
+		for (i = 0; i < 8; i++) {
+			gpio_irq = EP93XX_GPIO_F_IRQ_BASE + i;
+			irq_set_chip_data(gpio_irq, &epg->gc[5]);
+			irq_set_chip_and_handler(gpio_irq,
+						 girq->chip,
+						 handle_level_irq);
+			irq_clear_status_flags(gpio_irq, IRQ_NOREQUEST);
+		}
+		girq->default_type = IRQ_TYPE_NONE;
+		girq->handler = handle_level_irq;
+		gc->to_irq = ep93xx_gpio_f_to_irq;
+	}
+
+	return devm_gpiochip_add_data(dev, gc, epg);
+}
+
+static int ep93xx_gpio_probe(struct platform_device *pdev)
+{
+	struct ep93xx_gpio *epg;
+	int i;
+
+	epg = devm_kzalloc(&pdev->dev, sizeof(*epg), GFP_KERNEL);
+	if (!epg)
+		return -ENOMEM;
+
+	epg->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(epg->base))
+		return PTR_ERR(epg->base);
+
+	for (i = 0; i < ARRAY_SIZE(ep93xx_gpio_banks); i++) {
+		struct ep93xx_gpio_chip *gc = &epg->gc[i];
+		struct ep93xx_gpio_bank *bank = &ep93xx_gpio_banks[i];
+
+		if (ep93xx_gpio_add_bank(gc, pdev, epg, bank))
+			dev_warn(&pdev->dev, "Unable to add gpio bank %s\n",
+				 bank->label);
+	}
+
+	return 0;
+}
+
+static struct platform_driver ep93xx_gpio_driver = {
+	.driver		= {
+		.name	= "gpio-ep93xx",
+	},
+	.probe		= ep93xx_gpio_probe,
+};
+
+static int __init ep93xx_gpio_init(void)
+{
+	return platform_driver_register(&ep93xx_gpio_driver);
+}
+postcore_initcall(ep93xx_gpio_init);
+
+MODULE_AUTHOR("Ryan Mallon <ryan@bluewatersys.com> "
+		"H Hartley Sweeten <hsweeten@visionengravers.com>");
+MODULE_DESCRIPTION("EP93XX GPIO driver");
+MODULE_LICENSE("GPL");