Merge tag 'gpio-v3.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio into next

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v3.16 series.

  There is a lot of action in the GPIO subsystem doing refactorings and
  cleanups, almost as many deletions as insertions and minor feature
  growth and no new drivers this time.  Which is actually pretty nice.
  Some GPIO-related stuff will come in through the pin control tree as
  well.

  Details:

   - We are finalizing and fixing up the gpiochip irqchip helpers
     bringing a helpful irqchip implementation into the gpiolib core and
     avoiding duplicate code and, more importantly, duplicate bug fixes:

     * Support for using the helpers with threaded interrupt handlers as
       used on sleeping GPIO-irqchips

     * Do not set up hardware triggers for edges or levels if the
       default IRQ type is IRQ_TYPE_NONE - some drivers would exploit
       the fact that you could get default initialization of the IRQ
       type from the core at probe() but if no default type is set up
       from the helper, we should not call the driver to configure
       anything.  Wait until a consumer requests the interrupt instead.

     * Make the irqchip helpers put the GPIO irqs into their own lock
       class.  The GPIO irqchips can often emit (harmless, but annoying)
       lockdep warnings about recursions when they are in fact just
       cascaded IRQs.  By putting them into their own lock class we help
       the lockdep core to keep track of things.

     * Switch the tc3589x GPIO expanders to use the irqchip helpers

     * Switch the OMAP GPIO driver to use the irqchip helpers

     * Add some documentation for the irqchip helpers

     * select IRQ_DOMAIN when using the helpers since some platforms may
       not be using this by default and it's a strict dependency.

   - Continued GPIO descriptor refactoring:

     * Remove the one instance of gpio_to_desc() from the device tree
       code, making the OF GPIO code use GPIO descriptors only.

     * Introduce gpiod_get_optional() and gpiod_get_optional_index()
       akin to the similar regulator functions for cases where the use
       of GPIO is optional and not strictly required.

     * Make of_get_named_gpiod_flags() private - we do not want to
       unnecessarily expose APIs to drivers that make the gpiolib harder
       than necessary to maintain and refactor.  Privatize this
       function.

   - Support "-gpio" suffix for the OF GPIO retrieveal path.  We used to
     look for "foo-gpios" or just "gpios" in device tree nodes, but it
     turns out that some drivers with a single GPIO line will just state
     "foo-gpio" (singularis).  Sigh.  Support this with a fallback
     looking for it, as this simplifies driver code and handles it in
     core code.

   - Switch the ACPI GPIO core to fetch GPIOs with the *_cansleep
     function variants as the GPIO operation region handler can sleep,
     and shall be able to handle gpiochips that sleep.

   - Tons of cleanups and janitorial work from Jingoo Han, Axel Lin,
     Javier Martinez Canillas and Abdoulaye Berthe.  Notably Jingoo cut
     off a ton of pointless OOM messages.

   - Incremental development and fixes for various drivers, nothing
     really special here"

* tag 'gpio-v3.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (85 commits)
  gpio: select IRQ_DOMAIN for gpiolib irqchip helpers
  gpio: pca953x: use gpiolib irqchip helpers
  gpio: pcf857x: Add IRQF_SHARED when request irq
  gpio: pcf857x: Avoid calling irq_domain_cleanup twice
  gpio: mcp23s08: switch chip count to int
  gpio: dwapb: use a second irq chip
  gpio: ep93xx: Use devm_ioremap_resource()
  gpio: mcp23s08: fixed count variable for devicetree probing
  gpio: Add run-time dependencies to R-Car driver
  gpio: pch: add slab include
  Documentation / ACPI: Fix location of GPIO documentation
  gpio / ACPI: use *_cansleep version of gpiod_get/set APIs
  gpio: generic: add request function pointer
  gpio-pch: Fix Kconfig dependencies
  gpio: make of_get_named_gpiod_flags() private
  gpio: gpioep93xx: use devm functions
  gpio: janzttl: use devm function
  gpio: timberdale: use devm functions
  gpio: bt8xx: use devm function for memory allocation
  gpio: include linux/bug.h in interface header
  ...

4 files changed, 48 insertions, 34 deletions

diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h
index bed128e8f4b1..05e53ccb708b 100644
--- a/include/linux/gpio/consumer.h
+++ b/include/linux/gpio/consumer.h
@@ -1,6 +1,7 @@
 #ifndef __LINUX_GPIO_CONSUMER_H
 #define __LINUX_GPIO_CONSUMER_H
 
+#include <linux/bug.h>
 #include <linux/err.h>
 #include <linux/kernel.h>
 
@@ -23,6 +24,12 @@ struct gpio_desc *__must_check gpiod_get(struct device *dev,
 struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
 					       const char *con_id,
 					       unsigned int idx);
+struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
+						  const char *con_id);
+struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
+							const char *con_id,
+							unsigned int index);
+
 void gpiod_put(struct gpio_desc *desc);
 
 struct gpio_desc *__must_check devm_gpiod_get(struct device *dev,
@@ -30,6 +37,12 @@ struct gpio_desc *__must_check devm_gpiod_get(struct device *dev,
 struct gpio_desc *__must_check devm_gpiod_get_index(struct device *dev,
 						    const char *con_id,
 						    unsigned int idx);
+struct gpio_desc *__must_check devm_gpiod_get_optional(struct device *dev,
+						       const char *con_id);
+struct gpio_desc *__must_check
+devm_gpiod_get_index_optional(struct device *dev, const char *con_id,
+			      unsigned int index);
+
 void devm_gpiod_put(struct device *dev, struct gpio_desc *desc);
 
 int gpiod_get_direction(const struct gpio_desc *desc);
@@ -73,6 +86,20 @@ static inline struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
 {
 	return ERR_PTR(-ENOSYS);
 }
+
+static inline struct gpio_desc *__must_check
+gpiod_get_optional(struct device *dev, const char *con_id)
+{
+	return ERR_PTR(-ENOSYS);
+}
+
+static inline struct gpio_desc *__must_check
+gpiod_get_index_optional(struct device *dev, const char *con_id,
+			 unsigned int index)
+{
+	return ERR_PTR(-ENOSYS);
+}
+
 static inline void gpiod_put(struct gpio_desc *desc)
 {
 	might_sleep();
@@ -93,6 +120,20 @@ struct gpio_desc *__must_check devm_gpiod_get_index(struct device *dev,
 {
 	return ERR_PTR(-ENOSYS);
 }
+
+static inline struct gpio_desc *__must_check
+devm_gpiod_get_optional(struct device *dev, const char *con_id)
+{
+	return ERR_PTR(-ENOSYS);
+}
+
+static inline struct gpio_desc *__must_check
+devm_gpiod_get_index_optional(struct device *dev, const char *con_id,
+			      unsigned int index)
+{
+	return ERR_PTR(-ENOSYS);
+}
+
 static inline void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
 {
 	might_sleep();
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index 1827b43966d9..573e4f3243d0 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -51,7 +51,10 @@ struct seq_file;
  *      format specifier for an unsigned int.  It is substituted by the actual
  *      number of the gpio.
  * @can_sleep: flag must be set iff get()/set() methods sleep, as they
- *	must while accessing GPIO expander chips over I2C or SPI
+ *	must while accessing GPIO expander chips over I2C or SPI. This
+ *	implies that if the chip supports IRQs, these IRQs need to be threaded
+ *	as the chip access may sleep when e.g. reading out the IRQ status
+ *	registers.
  * @exported: flags if the gpiochip is exported for use from sysfs. Private.
  *
  * A gpio_chip can help platforms abstract various sources of GPIOs so
diff --git a/include/linux/mfd/tc3589x.h b/include/linux/mfd/tc3589x.h
index 6b8e1ff4672b..e6088c2e2092 100644
--- a/include/linux/mfd/tc3589x.h
+++ b/include/linux/mfd/tc3589x.h
@@ -111,7 +111,6 @@ enum tx3589x_block {
 #define TC3589x_INT_PORIRQ	7
 
 #define TC3589x_NR_INTERNAL_IRQS	8
-#define TC3589x_INT_GPIO(x)	(TC3589x_NR_INTERNAL_IRQS + (x))
 
 struct tc3589x {
 	struct mutex lock;
diff --git a/include/linux/of_gpio.h b/include/linux/of_gpio.h
index f14123a5a9df..38fc05036015 100644
--- a/include/linux/of_gpio.h
+++ b/include/linux/of_gpio.h
@@ -19,7 +19,6 @@
 #include <linux/errno.h>
 #include <linux/gpio.h>
 #include <linux/of.h>
-#include <linux/gpio/consumer.h>
 
 struct device_node;
 
@@ -48,7 +47,7 @@ static inline struct of_mm_gpio_chip *to_of_mm_gpio_chip(struct gpio_chip *gc)
 	return container_of(gc, struct of_mm_gpio_chip, gc);
 }
 
-extern struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
+extern int of_get_named_gpio_flags(struct device_node *np,
 		const char *list_name, int index, enum of_gpio_flags *flags);
 
 extern int of_mm_gpiochip_add(struct device_node *np,
@@ -63,10 +62,10 @@ extern int of_gpio_simple_xlate(struct gpio_chip *gc,
 #else /* CONFIG_OF_GPIO */
 
 /* Drivers may not strictly depend on the GPIO support, so let them link. */
-static inline struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
+static inline int of_get_named_gpio_flags(struct device_node *np,
 		const char *list_name, int index, enum of_gpio_flags *flags)
 {
-	return ERR_PTR(-ENOSYS);
+	return -ENOSYS;
 }
 
 static inline int of_gpio_simple_xlate(struct gpio_chip *gc,
@@ -81,18 +80,6 @@ static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
 
 #endif /* CONFIG_OF_GPIO */
 
-static inline int of_get_named_gpio_flags(struct device_node *np,
-		const char *list_name, int index, enum of_gpio_flags *flags)
-{
-	struct gpio_desc *desc;
-	desc = of_get_named_gpiod_flags(np, list_name, index, flags);
-
-	if (IS_ERR(desc))
-		return PTR_ERR(desc);
-	else
-		return desc_to_gpio(desc);
-}
-
 /**
  * of_gpio_named_count() - Count GPIOs for a device
  * @np:		device node to count GPIOs for
@@ -129,22 +116,6 @@ static inline int of_gpio_count(struct device_node *np)
 	return of_gpio_named_count(np, "gpios");
 }
 
-/**
- * of_get_gpiod_flags() - Get a GPIO descriptor and flags to use with GPIO API
- * @np:		device node to get GPIO from
- * @index:	index of the GPIO
- * @flags:	a flags pointer to fill in
- *
- * Returns GPIO descriptor to use with Linux generic GPIO API, or a errno
- * value on the error condition. If @flags is not NULL the function also fills
- * in flags for the GPIO.
- */
-static inline struct gpio_desc *of_get_gpiod_flags(struct device_node *np,
-					int index, enum of_gpio_flags *flags)
-{
-	return of_get_named_gpiod_flags(np, "gpios", index, flags);
-}
-
 static inline int of_get_gpio_flags(struct device_node *np, int index,
 		      enum of_gpio_flags *flags)
 {