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path: root/drivers/gpio/gpio-em.c
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-rw-r--r--drivers/gpio/gpio-em.c390
1 files changed, 390 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-em.c b/drivers/gpio/gpio-em.c
new file mode 100644
index 0000000000..858e6ebbb5
--- /dev/null
+++ b/drivers/gpio/gpio-em.c
@@ -0,0 +1,390 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Emma Mobile GPIO Support - GIO
+ *
+ * Copyright (C) 2012 Magnus Damm
+ */
+
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/gpio/driver.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/pinctrl/consumer.h>
+
+struct em_gio_priv {
+ void __iomem *base0;
+ void __iomem *base1;
+ spinlock_t sense_lock;
+ struct platform_device *pdev;
+ struct gpio_chip gpio_chip;
+ struct irq_chip irq_chip;
+ struct irq_domain *irq_domain;
+};
+
+#define GIO_E1 0x00
+#define GIO_E0 0x04
+#define GIO_EM 0x04
+#define GIO_OL 0x08
+#define GIO_OH 0x0c
+#define GIO_I 0x10
+#define GIO_IIA 0x14
+#define GIO_IEN 0x18
+#define GIO_IDS 0x1c
+#define GIO_IIM 0x1c
+#define GIO_RAW 0x20
+#define GIO_MST 0x24
+#define GIO_IIR 0x28
+
+#define GIO_IDT0 0x40
+#define GIO_IDT1 0x44
+#define GIO_IDT2 0x48
+#define GIO_IDT3 0x4c
+#define GIO_RAWBL 0x50
+#define GIO_RAWBH 0x54
+#define GIO_IRBL 0x58
+#define GIO_IRBH 0x5c
+
+#define GIO_IDT(n) (GIO_IDT0 + ((n) * 4))
+
+static inline unsigned long em_gio_read(struct em_gio_priv *p, int offs)
+{
+ if (offs < GIO_IDT0)
+ return ioread32(p->base0 + offs);
+ else
+ return ioread32(p->base1 + (offs - GIO_IDT0));
+}
+
+static inline void em_gio_write(struct em_gio_priv *p, int offs,
+ unsigned long value)
+{
+ if (offs < GIO_IDT0)
+ iowrite32(value, p->base0 + offs);
+ else
+ iowrite32(value, p->base1 + (offs - GIO_IDT0));
+}
+
+static void em_gio_irq_disable(struct irq_data *d)
+{
+ struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
+
+ em_gio_write(p, GIO_IDS, BIT(irqd_to_hwirq(d)));
+}
+
+static void em_gio_irq_enable(struct irq_data *d)
+{
+ struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
+
+ em_gio_write(p, GIO_IEN, BIT(irqd_to_hwirq(d)));
+}
+
+static int em_gio_irq_reqres(struct irq_data *d)
+{
+ struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
+ int ret;
+
+ ret = gpiochip_lock_as_irq(&p->gpio_chip, irqd_to_hwirq(d));
+ if (ret) {
+ dev_err(p->gpio_chip.parent,
+ "unable to lock HW IRQ %lu for IRQ\n",
+ irqd_to_hwirq(d));
+ return ret;
+ }
+ return 0;
+}
+
+static void em_gio_irq_relres(struct irq_data *d)
+{
+ struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
+
+ gpiochip_unlock_as_irq(&p->gpio_chip, irqd_to_hwirq(d));
+}
+
+
+#define GIO_ASYNC(x) (x + 8)
+
+static unsigned char em_gio_sense_table[IRQ_TYPE_SENSE_MASK + 1] = {
+ [IRQ_TYPE_EDGE_RISING] = GIO_ASYNC(0x00),
+ [IRQ_TYPE_EDGE_FALLING] = GIO_ASYNC(0x01),
+ [IRQ_TYPE_LEVEL_HIGH] = GIO_ASYNC(0x02),
+ [IRQ_TYPE_LEVEL_LOW] = GIO_ASYNC(0x03),
+ [IRQ_TYPE_EDGE_BOTH] = GIO_ASYNC(0x04),
+};
+
+static int em_gio_irq_set_type(struct irq_data *d, unsigned int type)
+{
+ unsigned char value = em_gio_sense_table[type & IRQ_TYPE_SENSE_MASK];
+ struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
+ unsigned int reg, offset, shift;
+ unsigned long flags;
+ unsigned long tmp;
+
+ if (!value)
+ return -EINVAL;
+
+ offset = irqd_to_hwirq(d);
+
+ pr_debug("gio: sense irq = %d, mode = %d\n", offset, value);
+
+ /* 8 x 4 bit fields in 4 IDT registers */
+ reg = GIO_IDT(offset >> 3);
+ shift = (offset & 0x07) << 4;
+
+ spin_lock_irqsave(&p->sense_lock, flags);
+
+ /* disable the interrupt in IIA */
+ tmp = em_gio_read(p, GIO_IIA);
+ tmp &= ~BIT(offset);
+ em_gio_write(p, GIO_IIA, tmp);
+
+ /* change the sense setting in IDT */
+ tmp = em_gio_read(p, reg);
+ tmp &= ~(0xf << shift);
+ tmp |= value << shift;
+ em_gio_write(p, reg, tmp);
+
+ /* clear pending interrupts */
+ em_gio_write(p, GIO_IIR, BIT(offset));
+
+ /* enable the interrupt in IIA */
+ tmp = em_gio_read(p, GIO_IIA);
+ tmp |= BIT(offset);
+ em_gio_write(p, GIO_IIA, tmp);
+
+ spin_unlock_irqrestore(&p->sense_lock, flags);
+
+ return 0;
+}
+
+static irqreturn_t em_gio_irq_handler(int irq, void *dev_id)
+{
+ struct em_gio_priv *p = dev_id;
+ unsigned long pending;
+ unsigned int offset, irqs_handled = 0;
+
+ while ((pending = em_gio_read(p, GIO_MST))) {
+ offset = __ffs(pending);
+ em_gio_write(p, GIO_IIR, BIT(offset));
+ generic_handle_domain_irq(p->irq_domain, offset);
+ irqs_handled++;
+ }
+
+ return irqs_handled ? IRQ_HANDLED : IRQ_NONE;
+}
+
+static inline struct em_gio_priv *gpio_to_priv(struct gpio_chip *chip)
+{
+ return gpiochip_get_data(chip);
+}
+
+static int em_gio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+ em_gio_write(gpio_to_priv(chip), GIO_E0, BIT(offset));
+ return 0;
+}
+
+static int em_gio_get(struct gpio_chip *chip, unsigned offset)
+{
+ return !!(em_gio_read(gpio_to_priv(chip), GIO_I) & BIT(offset));
+}
+
+static void __em_gio_set(struct gpio_chip *chip, unsigned int reg,
+ unsigned shift, int value)
+{
+ /* upper 16 bits contains mask and lower 16 actual value */
+ em_gio_write(gpio_to_priv(chip), reg,
+ (BIT(shift + 16)) | (value << shift));
+}
+
+static void em_gio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ /* output is split into two registers */
+ if (offset < 16)
+ __em_gio_set(chip, GIO_OL, offset, value);
+ else
+ __em_gio_set(chip, GIO_OH, offset - 16, value);
+}
+
+static int em_gio_direction_output(struct gpio_chip *chip, unsigned offset,
+ int value)
+{
+ /* write GPIO value to output before selecting output mode of pin */
+ em_gio_set(chip, offset, value);
+ em_gio_write(gpio_to_priv(chip), GIO_E1, BIT(offset));
+ return 0;
+}
+
+static int em_gio_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+ return irq_create_mapping(gpio_to_priv(chip)->irq_domain, offset);
+}
+
+static int em_gio_request(struct gpio_chip *chip, unsigned offset)
+{
+ return pinctrl_gpio_request(chip->base + offset);
+}
+
+static void em_gio_free(struct gpio_chip *chip, unsigned offset)
+{
+ pinctrl_gpio_free(chip->base + offset);
+
+ /* Set the GPIO as an input to ensure that the next GPIO request won't
+ * drive the GPIO pin as an output.
+ */
+ em_gio_direction_input(chip, offset);
+}
+
+static int em_gio_irq_domain_map(struct irq_domain *h, unsigned int irq,
+ irq_hw_number_t hwirq)
+{
+ struct em_gio_priv *p = h->host_data;
+
+ pr_debug("gio: map hw irq = %d, irq = %d\n", (int)hwirq, irq);
+
+ irq_set_chip_data(irq, h->host_data);
+ irq_set_chip_and_handler(irq, &p->irq_chip, handle_level_irq);
+ return 0;
+}
+
+static const struct irq_domain_ops em_gio_irq_domain_ops = {
+ .map = em_gio_irq_domain_map,
+ .xlate = irq_domain_xlate_twocell,
+};
+
+static void em_gio_irq_domain_remove(void *data)
+{
+ struct irq_domain *domain = data;
+
+ irq_domain_remove(domain);
+}
+
+static int em_gio_probe(struct platform_device *pdev)
+{
+ struct em_gio_priv *p;
+ struct gpio_chip *gpio_chip;
+ struct irq_chip *irq_chip;
+ struct device *dev = &pdev->dev;
+ const char *name = dev_name(dev);
+ unsigned int ngpios;
+ int irq[2], ret;
+
+ p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL);
+ if (!p)
+ return -ENOMEM;
+
+ p->pdev = pdev;
+ platform_set_drvdata(pdev, p);
+ spin_lock_init(&p->sense_lock);
+
+ irq[0] = platform_get_irq(pdev, 0);
+ if (irq[0] < 0)
+ return irq[0];
+
+ irq[1] = platform_get_irq(pdev, 1);
+ if (irq[1] < 0)
+ return irq[1];
+
+ p->base0 = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(p->base0))
+ return PTR_ERR(p->base0);
+
+ p->base1 = devm_platform_ioremap_resource(pdev, 1);
+ if (IS_ERR(p->base1))
+ return PTR_ERR(p->base1);
+
+ if (of_property_read_u32(dev->of_node, "ngpios", &ngpios)) {
+ dev_err(dev, "Missing ngpios OF property\n");
+ return -EINVAL;
+ }
+
+ gpio_chip = &p->gpio_chip;
+ gpio_chip->direction_input = em_gio_direction_input;
+ gpio_chip->get = em_gio_get;
+ gpio_chip->direction_output = em_gio_direction_output;
+ gpio_chip->set = em_gio_set;
+ gpio_chip->to_irq = em_gio_to_irq;
+ gpio_chip->request = em_gio_request;
+ gpio_chip->free = em_gio_free;
+ gpio_chip->label = name;
+ gpio_chip->parent = dev;
+ gpio_chip->owner = THIS_MODULE;
+ gpio_chip->base = -1;
+ gpio_chip->ngpio = ngpios;
+
+ irq_chip = &p->irq_chip;
+ irq_chip->name = "gpio-em";
+ irq_chip->irq_mask = em_gio_irq_disable;
+ irq_chip->irq_unmask = em_gio_irq_enable;
+ irq_chip->irq_set_type = em_gio_irq_set_type;
+ irq_chip->irq_request_resources = em_gio_irq_reqres;
+ irq_chip->irq_release_resources = em_gio_irq_relres;
+ irq_chip->flags = IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND;
+
+ p->irq_domain = irq_domain_add_simple(dev->of_node, ngpios, 0,
+ &em_gio_irq_domain_ops, p);
+ if (!p->irq_domain) {
+ dev_err(dev, "cannot initialize irq domain\n");
+ return -ENXIO;
+ }
+
+ ret = devm_add_action_or_reset(dev, em_gio_irq_domain_remove,
+ p->irq_domain);
+ if (ret)
+ return ret;
+
+ if (devm_request_irq(dev, irq[0], em_gio_irq_handler, 0, name, p)) {
+ dev_err(dev, "failed to request low IRQ\n");
+ return -ENOENT;
+ }
+
+ if (devm_request_irq(dev, irq[1], em_gio_irq_handler, 0, name, p)) {
+ dev_err(dev, "failed to request high IRQ\n");
+ return -ENOENT;
+ }
+
+ ret = devm_gpiochip_add_data(dev, gpio_chip, p);
+ if (ret) {
+ dev_err(dev, "failed to add GPIO controller\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id em_gio_dt_ids[] = {
+ { .compatible = "renesas,em-gio", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, em_gio_dt_ids);
+
+static struct platform_driver em_gio_device_driver = {
+ .probe = em_gio_probe,
+ .driver = {
+ .name = "em_gio",
+ .of_match_table = em_gio_dt_ids,
+ }
+};
+
+static int __init em_gio_init(void)
+{
+ return platform_driver_register(&em_gio_device_driver);
+}
+postcore_initcall(em_gio_init);
+
+static void __exit em_gio_exit(void)
+{
+ platform_driver_unregister(&em_gio_device_driver);
+}
+module_exit(em_gio_exit);
+
+MODULE_AUTHOR("Magnus Damm");
+MODULE_DESCRIPTION("Renesas Emma Mobile GIO Driver");
+MODULE_LICENSE("GPL v2");