1 files changed, 358 insertions, 124 deletions

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 716ee9843110..401add28933f 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -16,16 +16,35 @@
 #include <linux/export.h>
 #include <linux/acpi.h>
 #include <linux/interrupt.h>
+#include <linux/mutex.h>
 
 #include "gpiolib.h"
 
-struct acpi_gpio_evt_pin {
+struct acpi_gpio_event {
 	struct list_head node;
-	acpi_handle *evt_handle;
+	acpi_handle handle;
 	unsigned int pin;
 	unsigned int irq;
 };
 
+struct acpi_gpio_connection {
+	struct list_head node;
+	struct gpio_desc *desc;
+};
+
+struct acpi_gpio_chip {
+	/*
+	 * ACPICA requires that the first field of the context parameter
+	 * passed to acpi_install_address_space_handler() is large enough
+	 * to hold struct acpi_connection_info.
+	 */
+	struct acpi_connection_info conn_info;
+	struct list_head conns;
+	struct mutex conn_lock;
+	struct gpio_chip *chip;
+	struct list_head events;
+};
+
 static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
 {
 	if (!gc->dev)
@@ -60,176 +79,195 @@ static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
 	if (pin < 0 || pin > chip->ngpio)
 		return ERR_PTR(-EINVAL);
 
-	return gpio_to_desc(chip->base + pin);
+	return gpiochip_get_desc(chip, pin);
 }
 
 static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
 {
-	acpi_handle handle = data;
+	struct acpi_gpio_event *event = data;
 
-	acpi_evaluate_object(handle, NULL, NULL, NULL);
+	acpi_evaluate_object(event->handle, NULL, NULL, NULL);
 
 	return IRQ_HANDLED;
 }
 
 static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
 {
-	struct acpi_gpio_evt_pin *evt_pin = data;
+	struct acpi_gpio_event *event = data;
 
-	acpi_execute_simple_method(evt_pin->evt_handle, NULL, evt_pin->pin);
+	acpi_execute_simple_method(event->handle, NULL, event->pin);
 
 	return IRQ_HANDLED;
 }
 
-static void acpi_gpio_evt_dh(acpi_handle handle, void *data)
+static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
 {
 	/* The address of this function is used as a key. */
 }
 
-/**
- * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
- * @chip:      gpio chip
- *
- * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
- * handled by ACPI event methods which need to be called from the GPIO
- * chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
- * gpio pins have acpi event methods and assigns interrupt handlers that calls
- * the acpi event methods for those pins.
- */
-static void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
+static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
+						   void *context)
 {
-	struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
-	struct acpi_resource *res;
+	struct acpi_gpio_chip *acpi_gpio = context;
+	struct gpio_chip *chip = acpi_gpio->chip;
+	struct acpi_resource_gpio *agpio;
 	acpi_handle handle, evt_handle;
-	struct list_head *evt_pins = NULL;
-	acpi_status status;
-	unsigned int pin;
-	int irq, ret;
-	char ev_name[5];
+	struct acpi_gpio_event *event;
+	irq_handler_t handler = NULL;
+	struct gpio_desc *desc;
+	unsigned long irqflags;
+	int ret, pin, irq;
 
-	if (!chip->dev || !chip->to_irq)
-		return;
+	if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
+		return AE_OK;
 
-	handle = ACPI_HANDLE(chip->dev);
-	if (!handle)
-		return;
+	agpio = &ares->data.gpio;
+	if (agpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
+		return AE_OK;
 
-	status = acpi_get_event_resources(handle, &buf);
-	if (ACPI_FAILURE(status))
-		return;
+	handle = ACPI_HANDLE(chip->dev);
+	pin = agpio->pin_table[0];
+
+	if (pin <= 255) {
+		char ev_name[5];
+		sprintf(ev_name, "_%c%02X",
+			agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
+			pin);
+		if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
+			handler = acpi_gpio_irq_handler;
+	}
+	if (!handler) {
+		if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
+			handler = acpi_gpio_irq_handler_evt;
+	}
+	if (!handler)
+		return AE_BAD_PARAMETER;
 
-	status = acpi_get_handle(handle, "_EVT", &evt_handle);
-	if (ACPI_SUCCESS(status)) {
-		evt_pins = kzalloc(sizeof(*evt_pins), GFP_KERNEL);
-		if (evt_pins) {
-			INIT_LIST_HEAD(evt_pins);
-			status = acpi_attach_data(handle, acpi_gpio_evt_dh,
-						  evt_pins);
-			if (ACPI_FAILURE(status)) {
-				kfree(evt_pins);
-				evt_pins = NULL;
-			}
-		}
+	desc = gpiochip_get_desc(chip, pin);
+	if (IS_ERR(desc)) {
+		dev_err(chip->dev, "Failed to get GPIO descriptor\n");
+		return AE_ERROR;
 	}
 
-	/*
-	 * If a GPIO interrupt has an ACPI event handler method, or _EVT is
-	 * present, set up an interrupt handler that calls the ACPI event
-	 * handler.
-	 */
-	for (res = buf.pointer;
-	     res && (res->type != ACPI_RESOURCE_TYPE_END_TAG);
-	     res = ACPI_NEXT_RESOURCE(res)) {
-		irq_handler_t handler = NULL;
-		void *data;
-
-		if (res->type != ACPI_RESOURCE_TYPE_GPIO ||
-		    res->data.gpio.connection_type !=
-		    ACPI_RESOURCE_GPIO_TYPE_INT)
-			continue;
+	ret = gpiochip_request_own_desc(desc, "ACPI:Event");
+	if (ret) {
+		dev_err(chip->dev, "Failed to request GPIO\n");
+		return AE_ERROR;
+	}
 
-		pin = res->data.gpio.pin_table[0];
-		if (pin > chip->ngpio)
-			continue;
+	gpiod_direction_input(desc);
 
-		irq = chip->to_irq(chip, pin);
-		if (irq < 0)
-			continue;
+	ret = gpiod_lock_as_irq(desc);
+	if (ret) {
+		dev_err(chip->dev, "Failed to lock GPIO as interrupt\n");
+		goto fail_free_desc;
+	}
 
-		if (pin <= 255) {
-			acpi_handle ev_handle;
+	irq = gpiod_to_irq(desc);
+	if (irq < 0) {
+		dev_err(chip->dev, "Failed to translate GPIO to IRQ\n");
+		goto fail_unlock_irq;
+	}
 
-			sprintf(ev_name, "_%c%02X",
-				res->data.gpio.triggering ? 'E' : 'L', pin);
-			status = acpi_get_handle(handle, ev_name, &ev_handle);
-			if (ACPI_SUCCESS(status)) {
-				handler = acpi_gpio_irq_handler;
-				data = ev_handle;
-			}
+	irqflags = IRQF_ONESHOT;
+	if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
+		if (agpio->polarity == ACPI_ACTIVE_HIGH)
+			irqflags |= IRQF_TRIGGER_HIGH;
+		else
+			irqflags |= IRQF_TRIGGER_LOW;
+	} else {
+		switch (agpio->polarity) {
+		case ACPI_ACTIVE_HIGH:
+			irqflags |= IRQF_TRIGGER_RISING;
+			break;
+		case ACPI_ACTIVE_LOW:
+			irqflags |= IRQF_TRIGGER_FALLING;
+			break;
+		default:
+			irqflags |= IRQF_TRIGGER_RISING |
+				    IRQF_TRIGGER_FALLING;
+			break;
 		}
-		if (!handler && evt_pins) {
-			struct acpi_gpio_evt_pin *evt_pin;
+	}
 
-			evt_pin = kzalloc(sizeof(*evt_pin), GFP_KERNEL);
-			if (!evt_pin)
-				continue;
+	event = kzalloc(sizeof(*event), GFP_KERNEL);
+	if (!event)
+		goto fail_unlock_irq;
 
-			list_add_tail(&evt_pin->node, evt_pins);
-			evt_pin->evt_handle = evt_handle;
-			evt_pin->pin = pin;
-			evt_pin->irq = irq;
-			handler = acpi_gpio_irq_handler_evt;
-			data = evt_pin;
-		}
-		if (!handler)
-			continue;
+	event->handle = evt_handle;
+	event->irq = irq;
+	event->pin = pin;
 
-		/* Assume BIOS sets the triggering, so no flags */
-		ret = devm_request_threaded_irq(chip->dev, irq, NULL, handler,
-						0, "GPIO-signaled-ACPI-event",
-						data);
-		if (ret)
-			dev_err(chip->dev,
-				"Failed to request IRQ %d ACPI event handler\n",
-				irq);
+	ret = request_threaded_irq(event->irq, NULL, handler, irqflags,
+				   "ACPI:Event", event);
+	if (ret) {
+		dev_err(chip->dev, "Failed to setup interrupt handler for %d\n",
+			event->irq);
+		goto fail_free_event;
 	}
+
+	list_add_tail(&event->node, &acpi_gpio->events);
+	return AE_OK;
+
+fail_free_event:
+	kfree(event);
+fail_unlock_irq:
+	gpiod_unlock_as_irq(desc);
+fail_free_desc:
+	gpiochip_free_own_desc(desc);
+
+	return AE_ERROR;
 }
 
 /**
- * acpi_gpiochip_free_interrupts() - Free GPIO _EVT ACPI event interrupts.
- * @chip:      gpio chip
- *
- * Free interrupts associated with the _EVT method for the given GPIO chip.
+ * acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
+ * @acpi_gpio:      ACPI GPIO chip
  *
- * The remaining ACPI event interrupts associated with the chip are freed
- * automatically.
+ * ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
+ * handled by ACPI event methods which need to be called from the GPIO
+ * chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
+ * gpio pins have acpi event methods and assigns interrupt handlers that calls
+ * the acpi event methods for those pins.
  */
-static void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
+static void acpi_gpiochip_request_interrupts(struct acpi_gpio_chip *acpi_gpio)
 {
-	acpi_handle handle;
-	acpi_status status;
-	struct list_head *evt_pins;
-	struct acpi_gpio_evt_pin *evt_pin, *ep;
+	struct gpio_chip *chip = acpi_gpio->chip;
 
-	if (!chip->dev || !chip->to_irq)
+	if (!chip->to_irq)
 		return;
 
-	handle = ACPI_HANDLE(chip->dev);
-	if (!handle)
-		return;
+	INIT_LIST_HEAD(&acpi_gpio->events);
+	acpi_walk_resources(ACPI_HANDLE(chip->dev), "_AEI",
+			    acpi_gpiochip_request_interrupt, acpi_gpio);
+}
 
-	status = acpi_get_data(handle, acpi_gpio_evt_dh, (void **)&evt_pins);
-	if (ACPI_FAILURE(status))
+/**
+ * acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
+ * @acpi_gpio:      ACPI GPIO chip
+ *
+ * Free interrupts associated with GPIO ACPI event method for the given
+ * GPIO chip.
+ */
+static void acpi_gpiochip_free_interrupts(struct acpi_gpio_chip *acpi_gpio)
+{
+	struct acpi_gpio_event *event, *ep;
+	struct gpio_chip *chip = acpi_gpio->chip;
+
+	if (!chip->to_irq)
 		return;
 
-	list_for_each_entry_safe_reverse(evt_pin, ep, evt_pins, node) {
-		devm_free_irq(chip->dev, evt_pin->irq, evt_pin);
-		list_del(&evt_pin->node);
-		kfree(evt_pin);
-	}
+	list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
+		struct gpio_desc *desc;
 
-	acpi_detach_data(handle, acpi_gpio_evt_dh);
-	kfree(evt_pins);
+		free_irq(event->irq, event);
+		desc = gpiochip_get_desc(chip, event->pin);
+		if (WARN_ON(IS_ERR(desc)))
+			continue;
+		gpiod_unlock_as_irq(desc);
+		gpiochip_free_own_desc(desc);
+		list_del(&event->node);
+		kfree(event);
+	}
 }
 
 struct acpi_gpio_lookup {
@@ -310,12 +348,208 @@ struct gpio_desc *acpi_get_gpiod_by_index(struct device *dev, int index,
 	return lookup.desc ? lookup.desc : ERR_PTR(-ENOENT);
 }
 
+static acpi_status
+acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
+			    u32 bits, u64 *value, void *handler_context,
+			    void *region_context)
+{
+	struct acpi_gpio_chip *achip = region_context;
+	struct gpio_chip *chip = achip->chip;
+	struct acpi_resource_gpio *agpio;
+	struct acpi_resource *ares;
+	acpi_status status;
+	bool pull_up;
+	int i;
+
+	status = acpi_buffer_to_resource(achip->conn_info.connection,
+					 achip->conn_info.length, &ares);
+	if (ACPI_FAILURE(status))
+		return status;
+
+	if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
+		ACPI_FREE(ares);
+		return AE_BAD_PARAMETER;
+	}
+
+	agpio = &ares->data.gpio;
+	pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
+
+	if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
+	    function == ACPI_WRITE)) {
+		ACPI_FREE(ares);
+		return AE_BAD_PARAMETER;
+	}
+
+	for (i = 0; i < agpio->pin_table_length; i++) {
+		unsigned pin = agpio->pin_table[i];
+		struct acpi_gpio_connection *conn;
+		struct gpio_desc *desc;
+		bool found;
+
+		desc = gpiochip_get_desc(chip, pin);
+		if (IS_ERR(desc)) {
+			status = AE_ERROR;
+			goto out;
+		}
+
+		mutex_lock(&achip->conn_lock);
+
+		found = false;
+		list_for_each_entry(conn, &achip->conns, node) {
+			if (conn->desc == desc) {
+				found = true;
+				break;
+			}
+		}
+		if (!found) {
+			int ret;
+
+			ret = gpiochip_request_own_desc(desc, "ACPI:OpRegion");
+			if (ret) {
+				status = AE_ERROR;
+				mutex_unlock(&achip->conn_lock);
+				goto out;
+			}
+
+			switch (agpio->io_restriction) {
+			case ACPI_IO_RESTRICT_INPUT:
+				gpiod_direction_input(desc);
+				break;
+			case ACPI_IO_RESTRICT_OUTPUT:
+				/*
+				 * ACPI GPIO resources don't contain an
+				 * initial value for the GPIO. Therefore we
+				 * deduce that value from the pull field
+				 * instead. If the pin is pulled up we
+				 * assume default to be high, otherwise
+				 * low.
+				 */
+				gpiod_direction_output(desc, pull_up);
+				break;
+			default:
+				/*
+				 * Assume that the BIOS has configured the
+				 * direction and pull accordingly.
+				 */
+				break;
+			}
+
+			conn = kzalloc(sizeof(*conn), GFP_KERNEL);
+			if (!conn) {
+				status = AE_NO_MEMORY;
+				gpiochip_free_own_desc(desc);
+				mutex_unlock(&achip->conn_lock);
+				goto out;
+			}
+
+			conn->desc = desc;
+			list_add_tail(&conn->node, &achip->conns);
+		}
+
+		mutex_unlock(&achip->conn_lock);
+
+		if (function == ACPI_WRITE)
+			gpiod_set_raw_value(desc, !!((1 << i) & *value));
+		else
+			*value |= (u64)gpiod_get_raw_value(desc) << i;
+	}
+
+out:
+	ACPI_FREE(ares);
+	return status;
+}
+
+static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
+{
+	struct gpio_chip *chip = achip->chip;
+	acpi_handle handle = ACPI_HANDLE(chip->dev);
+	acpi_status status;
+
+	INIT_LIST_HEAD(&achip->conns);
+	mutex_init(&achip->conn_lock);
+	status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
+						    acpi_gpio_adr_space_handler,
+						    NULL, achip);
+	if (ACPI_FAILURE(status))
+		dev_err(chip->dev, "Failed to install GPIO OpRegion handler\n");
+}
+
+static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
+{
+	struct gpio_chip *chip = achip->chip;
+	acpi_handle handle = ACPI_HANDLE(chip->dev);
+	struct acpi_gpio_connection *conn, *tmp;
+	acpi_status status;
+
+	status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
+						   acpi_gpio_adr_space_handler);
+	if (ACPI_FAILURE(status)) {
+		dev_err(chip->dev, "Failed to remove GPIO OpRegion handler\n");
+		return;
+	}
+
+	list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
+		gpiochip_free_own_desc(conn->desc);
+		list_del(&conn->node);
+		kfree(conn);
+	}
+}
+
 void acpi_gpiochip_add(struct gpio_chip *chip)
 {
-	acpi_gpiochip_request_interrupts(chip);
+	struct acpi_gpio_chip *acpi_gpio;
+	acpi_handle handle;
+	acpi_status status;
+
+	if (!chip || !chip->dev)
+		return;
+
+	handle = ACPI_HANDLE(chip->dev);
+	if (!handle)
+		return;
+
+	acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
+	if (!acpi_gpio) {
+		dev_err(chip->dev,
+			"Failed to allocate memory for ACPI GPIO chip\n");
+		return;
+	}
+
+	acpi_gpio->chip = chip;
+
+	status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
+	if (ACPI_FAILURE(status)) {
+		dev_err(chip->dev, "Failed to attach ACPI GPIO chip\n");
+		kfree(acpi_gpio);
+		return;
+	}
+
+	acpi_gpiochip_request_interrupts(acpi_gpio);
+	acpi_gpiochip_request_regions(acpi_gpio);
 }
 
 void acpi_gpiochip_remove(struct gpio_chip *chip)
 {
-	acpi_gpiochip_free_interrupts(chip);
+	struct acpi_gpio_chip *acpi_gpio;
+	acpi_handle handle;
+	acpi_status status;
+
+	if (!chip || !chip->dev)
+		return;
+
+	handle = ACPI_HANDLE(chip->dev);
+	if (!handle)
+		return;
+
+	status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
+	if (ACPI_FAILURE(status)) {
+		dev_warn(chip->dev, "Failed to retrieve ACPI GPIO chip\n");
+		return;
+	}
+
+	acpi_gpiochip_free_regions(acpi_gpio);
+	acpi_gpiochip_free_interrupts(acpi_gpio);
+
+	acpi_detach_data(handle, acpi_gpio_chip_dh);
+	kfree(acpi_gpio);
 }