#include <linux/module.h>
#include <linux/bitops.h>
#include <linux/errno.h>
+#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/gpio/driver.h>
#include <linux/mfd/kempld.h>
#define KEMPLD_GPIO_MASK(x) (BIT((x) % 8))
#define KEMPLD_GPIO_DIR 0x40
#define KEMPLD_GPIO_LVL 0x42
+#define KEMPLD_GPIO_STS 0x44
#define KEMPLD_GPIO_EVT_LVL_EDGE 0x46
+#define KEMPLD_GPIO_EVT_LOW_HIGH 0x48
#define KEMPLD_GPIO_IEN 0x4A
+#define KEMPLD_GPIO_OUT_LVL 0x4E
+
+/* The IRQ to use if none was configured in the BIOS */
+static unsigned int gpio_irq;
+module_param_hw(gpio_irq, uint, irq, 0444);
+MODULE_PARM_DESC(gpio_irq, "Set legacy GPIO IRQ (1-15)");
struct kempld_gpio_data {
struct gpio_chip chip;
struct kempld_device_data *pld;
u8 out_lvl_reg;
+
+ struct mutex irq_lock;
+ u16 ien;
+ u16 evt_low_high;
+ u16 evt_lvl_edge;
};
/*
return evt ? __ffs(evt) : 16;
}
+static void kempld_irq_mask(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ struct kempld_gpio_data *gpio = gpiochip_get_data(chip);
+
+ gpio->ien &= ~BIT(irqd_to_hwirq(data));
+ gpiochip_disable_irq(chip, irqd_to_hwirq(data));
+}
+
+static void kempld_irq_unmask(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ struct kempld_gpio_data *gpio = gpiochip_get_data(chip);
+
+ gpiochip_enable_irq(chip, irqd_to_hwirq(data));
+ gpio->ien |= BIT(irqd_to_hwirq(data));
+}
+
+static int kempld_irq_set_type(struct irq_data *data, unsigned int type)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ struct kempld_gpio_data *gpio = gpiochip_get_data(chip);
+
+ switch (type) {
+ case IRQ_TYPE_EDGE_RISING:
+ gpio->evt_low_high |= BIT(data->hwirq);
+ gpio->evt_lvl_edge |= BIT(data->hwirq);
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ gpio->evt_low_high &= ~BIT(data->hwirq);
+ gpio->evt_lvl_edge |= BIT(data->hwirq);
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ gpio->evt_low_high |= BIT(data->hwirq);
+ gpio->evt_lvl_edge &= ~BIT(data->hwirq);
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ gpio->evt_low_high &= ~BIT(data->hwirq);
+ gpio->evt_lvl_edge &= ~BIT(data->hwirq);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void kempld_irq_bus_lock(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ struct kempld_gpio_data *gpio = gpiochip_get_data(chip);
+
+ mutex_lock(&gpio->irq_lock);
+}
+
+static void kempld_irq_bus_sync_unlock(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ struct kempld_gpio_data *gpio = gpiochip_get_data(chip);
+ struct kempld_device_data *pld = gpio->pld;
+
+ kempld_get_mutex(pld);
+ kempld_write16(pld, KEMPLD_GPIO_EVT_LVL_EDGE, gpio->evt_lvl_edge);
+ kempld_write16(pld, KEMPLD_GPIO_EVT_LOW_HIGH, gpio->evt_low_high);
+ kempld_write16(pld, KEMPLD_GPIO_IEN, gpio->ien);
+ kempld_release_mutex(pld);
+
+ mutex_unlock(&gpio->irq_lock);
+}
+
+static const struct irq_chip kempld_irqchip = {
+ .name = "kempld-gpio",
+ .irq_mask = kempld_irq_mask,
+ .irq_unmask = kempld_irq_unmask,
+ .irq_set_type = kempld_irq_set_type,
+ .irq_bus_lock = kempld_irq_bus_lock,
+ .irq_bus_sync_unlock = kempld_irq_bus_sync_unlock,
+ .flags = IRQCHIP_IMMUTABLE,
+ GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+static irqreturn_t kempld_gpio_irq_handler(int irq, void *data)
+{
+ struct kempld_gpio_data *gpio = data;
+ struct gpio_chip *chip = &gpio->chip;
+ unsigned int pin, child_irq;
+ unsigned long status;
+
+ kempld_get_mutex(gpio->pld);
+
+ status = kempld_read16(gpio->pld, KEMPLD_GPIO_STS);
+ if (status)
+ kempld_write16(gpio->pld, KEMPLD_GPIO_STS, status);
+
+ kempld_release_mutex(gpio->pld);
+
+ status &= gpio->ien;
+ if (!status)
+ return IRQ_NONE;
+
+ for_each_set_bit(pin, &status, chip->ngpio) {
+ child_irq = irq_find_mapping(chip->irq.domain, pin);
+ handle_nested_irq(child_irq);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int kempld_gpio_irq_init(struct device *dev,
+ struct kempld_gpio_data *gpio)
+{
+ struct kempld_device_data *pld = gpio->pld;
+ struct gpio_chip *chip = &gpio->chip;
+ struct gpio_irq_chip *girq;
+ unsigned int irq;
+ int ret;
+
+ /* Get the IRQ configured by the BIOS in the PLD */
+ kempld_get_mutex(pld);
+ irq = kempld_read8(pld, KEMPLD_IRQ_GPIO);
+ kempld_release_mutex(pld);
+
+ if (irq == 0xff) {
+ dev_info(dev, "GPIO controller has no IRQ support\n");
+ return 0;
+ }
+
+ /* Allow overriding the IRQ with the module parameter */
+ if (gpio_irq > 0) {
+ dev_warn(dev, "Forcing IRQ to %d\n", gpio_irq);
+ irq &= ~KEMPLD_IRQ_GPIO_MASK;
+ irq |= gpio_irq & KEMPLD_IRQ_GPIO_MASK;
+ }
+
+ if (!(irq & KEMPLD_IRQ_GPIO_MASK)) {
+ dev_warn(dev, "No IRQ configured\n");
+ return 0;
+ }
+
+ /* Get the current config, disable all child interrupts, clear them
+ * and set the parent IRQ
+ */
+ kempld_get_mutex(pld);
+ gpio->evt_low_high = kempld_read16(pld, KEMPLD_GPIO_EVT_LOW_HIGH);
+ gpio->evt_lvl_edge = kempld_read16(pld, KEMPLD_GPIO_EVT_LVL_EDGE);
+ kempld_write16(pld, KEMPLD_GPIO_IEN, 0);
+ kempld_write16(pld, KEMPLD_GPIO_STS, 0xFFFF);
+ kempld_write16(pld, KEMPLD_IRQ_GPIO, irq);
+ kempld_release_mutex(pld);
+
+ girq = &chip->irq;
+ gpio_irq_chip_set_chip(girq, &kempld_irqchip);
+
+ girq->parent_handler = NULL;
+ girq->num_parents = 0;
+ girq->parents = NULL;
+ girq->default_type = IRQ_TYPE_NONE;
+ girq->handler = handle_simple_irq;
+ girq->threaded = true;
+
+ mutex_init(&gpio->irq_lock);
+
+ ret = devm_request_threaded_irq(dev, irq & KEMPLD_IRQ_GPIO_MASK,
+ NULL, kempld_gpio_irq_handler,
+ IRQF_ONESHOT, chip->label,
+ gpio);
+ if (ret) {
+ dev_err(dev, "failed to request irq %d\n", irq);
+ return ret;
+ }
+
+ return 0;
+}
+
static int kempld_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
return -ENODEV;
}
+ ret = kempld_gpio_irq_init(dev, gpio);
+ if (ret)
+ return ret;
+
ret = devm_gpiochip_add_data(dev, chip, gpio);
if (ret) {
dev_err(dev, "Could not register GPIO chip\n");
projects / thirdparty / kernel / linux.git / commitdiff
