Merge branch 'next' (accumulated 3.16 merge window patches) into master

Now that 3.15 is released, this merges the 'next' branch into 'master',
bringing us to the normal situation where my 'master' branch is the
merge window.

* accumulated work in next: (6809 commits)
  ufs: sb mutex merge + mutex_destroy
  powerpc: update comments for generic idle conversion
  cris: update comments for generic idle conversion
  idle: remove cpu_idle() forward declarations
  nbd: zero from and len fields in NBD_CMD_DISCONNECT.
  mm: convert some level-less printks to pr_*
  MAINTAINERS: adi-buildroot-devel is moderated
  MAINTAINERS: add linux-api for review of API/ABI changes
  mm/kmemleak-test.c: use pr_fmt for logging
  fs/dlm/debug_fs.c: replace seq_printf by seq_puts
  fs/dlm/lockspace.c: convert simple_str to kstr
  fs/dlm/config.c: convert simple_str to kstr
  mm: mark remap_file_pages() syscall as deprecated
  mm: memcontrol: remove unnecessary memcg argument from soft limit functions
  mm: memcontrol: clean up memcg zoneinfo lookup
  mm/memblock.c: call kmemleak directly from memblock_(alloc|free)
  mm/mempool.c: update the kmemleak stack trace for mempool allocations
  lib/radix-tree.c: update the kmemleak stack trace for radix tree allocations
  mm: introduce kmemleak_update_trace()
  mm/kmemleak.c: use %u to print ->checksum
  ...

1 files changed, 83 insertions, 18 deletions

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index f48817d9748..d9c9cb4665d 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1363,6 +1363,11 @@ void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
 				  int parent_irq,
 				  irq_flow_handler_t parent_handler)
 {
+	if (gpiochip->can_sleep) {
+		chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n");
+		return;
+	}
+
 	irq_set_chained_handler(parent_irq, parent_handler);
 	/*
 	 * The parent irqchip is already using the chip_data for this
@@ -1372,6 +1377,12 @@ void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
 }
 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip);
 
+/*
+ * This lock class tells lockdep that GPIO irqs are in a different
+ * category than their parents, so it won't report false recursion.
+ */
+static struct lock_class_key gpiochip_irq_lock_class;
+
 /**
  * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
  * @d: the irqdomain used by this irqchip
@@ -1388,22 +1399,35 @@ static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
 	struct gpio_chip *chip = d->host_data;
 
 	irq_set_chip_data(irq, chip);
+	irq_set_lockdep_class(irq, &gpiochip_irq_lock_class);
 	irq_set_chip_and_handler(irq, chip->irqchip, chip->irq_handler);
+	/* Chips that can sleep need nested thread handlers */
+	if (chip->can_sleep)
+		irq_set_nested_thread(irq, 1);
 #ifdef CONFIG_ARM
 	set_irq_flags(irq, IRQF_VALID);
 #else
 	irq_set_noprobe(irq);
 #endif
-	irq_set_irq_type(irq, chip->irq_default_type);
+	/*
+	 * No set-up of the hardware will happen if IRQ_TYPE_NONE
+	 * is passed as default type.
+	 */
+	if (chip->irq_default_type != IRQ_TYPE_NONE)
+		irq_set_irq_type(irq, chip->irq_default_type);
 
 	return 0;
 }
 
 static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
 {
+	struct gpio_chip *chip = d->host_data;
+
 #ifdef CONFIG_ARM
 	set_irq_flags(irq, 0);
 #endif
+	if (chip->can_sleep)
+		irq_set_nested_thread(irq, 0);
 	irq_set_chip_and_handler(irq, NULL, NULL);
 	irq_set_chip_data(irq, NULL);
 }
@@ -1471,7 +1495,8 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
  * @first_irq: if not dynamically assigned, the base (first) IRQ to
  * allocate gpiochip irqs from
  * @handler: the irq handler to use (often a predefined irq core function)
- * @type: the default type for IRQs on this irqchip
+ * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
+ * to have the core avoid setting up any default type in the hardware.
  *
  * This function closely associates a certain irqchip with a certain
  * gpiochip, providing an irq domain to translate the local IRQs to
@@ -2571,22 +2596,27 @@ void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
 	mutex_unlock(&gpio_lookup_lock);
 }
 
-#ifdef CONFIG_OF
 static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
 				      unsigned int idx,
 				      enum gpio_lookup_flags *flags)
 {
+	static const char *suffixes[] = { "gpios", "gpio" };
 	char prop_name[32]; /* 32 is max size of property name */
 	enum of_gpio_flags of_flags;
 	struct gpio_desc *desc;
+	unsigned int i;
 
-	if (con_id)
-		snprintf(prop_name, 32, "%s-gpios", con_id);
-	else
-		snprintf(prop_name, 32, "gpios");
+	for (i = 0; i < ARRAY_SIZE(suffixes); i++) {
+		if (con_id)
+			snprintf(prop_name, 32, "%s-%s", con_id, suffixes[i]);
+		else
+			snprintf(prop_name, 32, "%s", suffixes[i]);
 
-	desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx,
-					&of_flags);
+		desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx,
+						&of_flags);
+		if (!IS_ERR(desc))
+			break;
+	}
 
 	if (IS_ERR(desc))
 		return desc;
@@ -2596,14 +2626,6 @@ static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
 
 	return desc;
 }
-#else
-static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
-				      unsigned int idx,
-				      enum gpio_lookup_flags *flags)
-{
-	return ERR_PTR(-ENODEV);
-}
-#endif
 
 static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id,
 					unsigned int idx,
@@ -2701,7 +2723,7 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
 }
 
 /**
- * gpio_get - obtain a GPIO for a given GPIO function
+ * gpiod_get - obtain a GPIO for a given GPIO function
  * @dev:	GPIO consumer, can be NULL for system-global GPIOs
  * @con_id:	function within the GPIO consumer
  *
@@ -2716,6 +2738,22 @@ struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id)
 EXPORT_SYMBOL_GPL(gpiod_get);
 
 /**
+ * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
+ * @dev: GPIO consumer, can be NULL for system-global GPIOs
+ * @con_id: function within the GPIO consumer
+ *
+ * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
+ * the requested function it will return NULL. This is convenient for drivers
+ * that need to handle optional GPIOs.
+ */
+struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
+						  const char *con_id)
+{
+	return gpiod_get_index_optional(dev, con_id, 0);
+}
+EXPORT_SYMBOL_GPL(gpiod_get_optional);
+
+/**
  * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
  * @dev:	GPIO consumer, can be NULL for system-global GPIOs
  * @con_id:	function within the GPIO consumer
@@ -2778,6 +2816,33 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
 EXPORT_SYMBOL_GPL(gpiod_get_index);
 
 /**
+ * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
+ *                            function
+ * @dev: GPIO consumer, can be NULL for system-global GPIOs
+ * @con_id: function within the GPIO consumer
+ * @index: index of the GPIO to obtain in the consumer
+ *
+ * This is equivalent to gpiod_get_index(), except that when no GPIO with the
+ * specified index was assigned to the requested function it will return NULL.
+ * This is convenient for drivers that need to handle optional GPIOs.
+ */
+struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
+							const char *con_id,
+							unsigned int index)
+{
+	struct gpio_desc *desc;
+
+	desc = gpiod_get_index(dev, con_id, index);
+	if (IS_ERR(desc)) {
+		if (PTR_ERR(desc) == -ENOENT)
+			return NULL;
+	}
+
+	return desc;
+}
+EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
+
+/**
  * gpiod_put - dispose of a GPIO descriptor
  * @desc:	GPIO descriptor to dispose of
  *