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-rw-r--r--drivers/gpio/Kconfig2
-rw-r--r--drivers/gpio/gpio-sch.c82
2 files changed, 83 insertions, 1 deletions
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index ad1a325be727..3a56a6370b6c 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -860,7 +860,7 @@ config GPIO_IT87
config GPIO_SCH
tristate "Intel SCH/TunnelCreek/Centerton/Quark X1000 GPIO"
- depends on (X86 || COMPILE_TEST) && PCI
+ depends on (X86 || COMPILE_TEST) && ACPI
select GPIOLIB_IRQCHIP
select MFD_CORE
select LPC_SCH
diff --git a/drivers/gpio/gpio-sch.c b/drivers/gpio/gpio-sch.c
index 06ab55d134b9..a6f0421d6e50 100644
--- a/drivers/gpio/gpio-sch.c
+++ b/drivers/gpio/gpio-sch.c
@@ -7,6 +7,7 @@
*/
#include <linux/acpi.h>
+#include <linux/bitops.h>
#include <linux/errno.h>
#include <linux/gpio/driver.h>
#include <linux/io.h>
@@ -29,12 +30,22 @@
#define CORE_BANK_OFFSET 0x00
#define RESUME_BANK_OFFSET 0x20
+/*
+ * iLB datasheet describes GPE0BLK registers, in particular GPE0E.GPIO bit.
+ * Document Number: 328195-001
+ */
+#define GPE0E_GPIO 14
+
struct sch_gpio {
struct gpio_chip chip;
struct irq_chip irqchip;
spinlock_t lock;
unsigned short iobase;
unsigned short resume_base;
+
+ /* GPE handling */
+ u32 gpe;
+ acpi_gpe_handler gpe_handler;
};
static unsigned int sch_gpio_offset(struct sch_gpio *sch, unsigned int gpio,
@@ -229,11 +240,74 @@ static void sch_irq_unmask(struct irq_data *d)
sch_irq_mask_unmask(d, 1);
}
+static u32 sch_gpio_gpe_handler(acpi_handle gpe_device, u32 gpe, void *context)
+{
+ struct sch_gpio *sch = context;
+ struct gpio_chip *gc = &sch->chip;
+ unsigned long core_status, resume_status;
+ unsigned long pending;
+ unsigned long flags;
+ int offset;
+ u32 ret;
+
+ spin_lock_irqsave(&sch->lock, flags);
+
+ core_status = inl(sch->iobase + CORE_BANK_OFFSET + GTS);
+ resume_status = inl(sch->iobase + RESUME_BANK_OFFSET + GTS);
+
+ spin_unlock_irqrestore(&sch->lock, flags);
+
+ pending = (resume_status << sch->resume_base) | core_status;
+ for_each_set_bit(offset, &pending, sch->chip.ngpio)
+ generic_handle_irq(irq_find_mapping(gc->irq.domain, offset));
+
+ /* Set returning value depending on whether we handled an interrupt */
+ ret = pending ? ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
+
+ /* Acknowledge GPE to ACPICA */
+ ret |= ACPI_REENABLE_GPE;
+
+ return ret;
+}
+
+static void sch_gpio_remove_gpe_handler(void *data)
+{
+ struct sch_gpio *sch = data;
+
+ acpi_disable_gpe(NULL, sch->gpe);
+ acpi_remove_gpe_handler(NULL, sch->gpe, sch->gpe_handler);
+}
+
+static int sch_gpio_install_gpe_handler(struct sch_gpio *sch)
+{
+ struct device *dev = sch->chip.parent;
+ acpi_status status;
+
+ status = acpi_install_gpe_handler(NULL, sch->gpe, ACPI_GPE_LEVEL_TRIGGERED,
+ sch->gpe_handler, sch);
+ if (ACPI_FAILURE(status)) {
+ dev_err(dev, "Failed to install GPE handler for %u: %s\n",
+ sch->gpe, acpi_format_exception(status));
+ return -ENODEV;
+ }
+
+ status = acpi_enable_gpe(NULL, sch->gpe);
+ if (ACPI_FAILURE(status)) {
+ dev_err(dev, "Failed to enable GPE handler for %u: %s\n",
+ sch->gpe, acpi_format_exception(status));
+ acpi_remove_gpe_handler(NULL, sch->gpe, sch->gpe_handler);
+ return -ENODEV;
+ }
+
+ return devm_add_action_or_reset(dev, sch_gpio_remove_gpe_handler, sch);
+}
+
static int sch_gpio_probe(struct platform_device *pdev)
{
struct gpio_irq_chip *girq;
struct sch_gpio *sch;
struct resource *res;
+ int ret;
sch = devm_kzalloc(&pdev->dev, sizeof(*sch), GFP_KERNEL);
if (!sch)
@@ -307,6 +381,14 @@ static int sch_gpio_probe(struct platform_device *pdev)
girq->default_type = IRQ_TYPE_NONE;
girq->handler = handle_bad_irq;
+ /* GPE setup is optional */
+ sch->gpe = GPE0E_GPIO;
+ sch->gpe_handler = sch_gpio_gpe_handler;
+
+ ret = sch_gpio_install_gpe_handler(sch);
+ if (ret)
+ dev_warn(&pdev->dev, "Can't setup GPE, no IRQ support\n");
+
return devm_gpiochip_add_data(&pdev->dev, &sch->chip, sch);
}