Merge tag 'gpio-v3.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO update from Linus Walleij:
 "This is the bulk of GPIO changes for the v3.17 development cycle, and
  this time we got a lot of action going on and it will continue:

   - The core GPIO library implementation has been split up in three
     different files:
     - gpiolib.c for the latest and greatest and shiny GPIO library code
       using GPIO descriptors only
     - gpiolib-legacy.c for the old integer number space API that we are
       phasing out gradually
     - gpiolib-sysfs.c for the sysfs interface that we are not entirely
       happy with, but has to live on for ABI compatibility

   - Add a flags argument to *gpiod_get* functions, with some
     backward-compatibility macros to ease transitions.  We should have
     had the flags there from the beginning it seems, now we need to
     clean up the mess.  There is a plan on how to move forward here
     devised by Alexandre Courbot and Mark Brown

   - Split off a special <linux/gpio/machine.h> header for the board
     gpio table registration, as per example from the regulator
     subsystem

   - Start to kill off the return value from gpiochip_remove() by
     removing the __must_check attribute and removing all checks inside
     the drivers/gpio directory.  The rationale is: well what were we
     supposed to do if there is an error code? Not much: print an error
     message.  And gpiolib already does that.  So make this function
     return void eventually

   - Some cleanups of hairy gpiolib code, make some functions not to be
     used outside the library private and make sure they are not
     exported, remove gpiod_lock/unlock_as_irq() as the existing
     function is for driver-internal use and fine as it is, delete
     gpio_ensure_requested() as it is not meaningful anymore

   - Support the GPIOF_ACTIVE_LOW flag from gpio_request_one() function
     calls, which is logical since this is already supported when
     referencing GPIOs from e.g. device trees

   - Switch STMPE, intel-mid, lynxpoint and ACPI (!) to use the gpiolib
     irqchip helpers cutting down on GPIO irqchip boilerplate a bit more

   - New driver for the Zynq GPIO block

   - The usual incremental improvements around a bunch of drivers

   - Janitorial syntactic and semantic cleanups by Jingoo Han, and
     Rickard Strandqvist especially"

* tag 'gpio-v3.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (37 commits)
  MAINTAINERS: update GPIO include files
  gpio: add missing includes in machine.h
  gpio: add flags argument to gpiod_get*() functions
  MAINTAINERS: Update Samsung pin control entry
  gpio / ACPI: Move event handling registration to gpiolib irqchip helpers
  gpio: lynxpoint: Convert to use gpiolib irqchip
  gpio: split gpiod board registration into machine header
  gpio: remove gpio_ensure_requested()
  gpio: remove useless check in gpiolib_sysfs_init()
  gpiolib: Export gpiochip_request_own_desc and gpiochip_free_own_desc
  gpio: move gpio_ensure_requested() into legacy C file
  gpio: remove gpiod_lock/unlock_as_irq()
  gpio: make gpiochip_get_desc() gpiolib-private
  gpio: simplify gpiochip_export()
  gpio: remove export of private of_get_named_gpio_flags()
  gpio: Add support for GPIOF_ACTIVE_LOW to gpio_request_one functions
  gpio: zynq: Clear pending interrupt when enabling a IRQ
  gpio: drop retval check enforcing from gpiochip_remove()
  gpio: remove all usage of gpio_remove retval in driver/gpio
  devicetree: Add Zynq GPIO devicetree bindings documentation
  ...

4 files changed, 70 insertions, 9 deletions

diff --git a/Documentation/devicetree/bindings/gpio/gpio-zynq.txt b/Documentation/devicetree/bindings/gpio/gpio-zynq.txt
new file mode 100644
index 000000000000..986371a4be2c
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-zynq.txt
@@ -0,0 +1,26 @@
+Xilinx Zynq GPIO controller Device Tree Bindings
+-------------------------------------------
+
+Required properties:
+- #gpio-cells           : Should be two
+                          - First cell is the GPIO line number
+                          - Second cell is used to specify optional
+                            parameters (unused)
+- compatible            : Should be "xlnx,zynq-gpio-1.0"
+- clocks                : Clock specifier (see clock bindings for details)
+- gpio-controller       : Marks the device node as a GPIO controller.
+- interrupts            : Interrupt specifier (see interrupt bindings for
+                          details)
+- interrupt-parent      : Must be core interrupt controller
+- reg                   : Address and length of the register set for the device
+
+Example:
+        gpio@e000a000 {
+                #gpio-cells = <2>;
+                compatible = "xlnx,zynq-gpio-1.0";
+                clocks = <&clkc 42>;
+                gpio-controller;
+                interrupt-parent = <&intc>;
+                interrupts = <0 20 4>;
+                reg = <0xe000a000 0x1000>;
+        };
diff --git a/Documentation/gpio/board.txt b/Documentation/gpio/board.txt
index ba169faad5c6..4452786225b8 100644
--- a/Documentation/gpio/board.txt
+++ b/Documentation/gpio/board.txt
@@ -60,7 +60,7 @@ Platform Data
 Finally, GPIOs can be bound to devices and functions using platform data. Board
 files that desire to do so need to include the following header:
 
-        #include <linux/gpio/driver.h>
+        #include <linux/gpio/machine.h>
 
 GPIOs are mapped by the means of tables of lookups, containing instances of the
 gpiod_lookup structure. Two macros are defined to help declaring such mappings:
diff --git a/Documentation/gpio/consumer.txt b/Documentation/gpio/consumer.txt
index d8abfc31abbe..76546324e968 100644
--- a/Documentation/gpio/consumer.txt
+++ b/Documentation/gpio/consumer.txt
@@ -29,13 +29,24 @@ gpiod_get() functions. Like many other kernel subsystems, gpiod_get() takes the
 device that will use the GPIO and the function the requested GPIO is supposed to
 fulfill:
 
-        struct gpio_desc *gpiod_get(struct device *dev, const char *con_id)
+        struct gpio_desc *gpiod_get(struct device *dev, const char *con_id,
+                                    enum gpiod_flags flags)
 
 If a function is implemented by using several GPIOs together (e.g. a simple LED
 device that displays digits), an additional index argument can be specified:
 
         struct gpio_desc *gpiod_get_index(struct device *dev,
-                                          const char *con_id, unsigned int idx)
+                                          const char *con_id, unsigned int idx,
+                                          enum gpiod_flags flags)
+
+The flags parameter is used to optionally specify a direction and initial value
+for the GPIO. Values can be:
+
+* GPIOD_ASIS or 0 to not initialize the GPIO at all. The direction must be set
+  later with one of the dedicated functions.
+* GPIOD_IN to initialize the GPIO as input.
+* GPIOD_OUT_LOW to initialize the GPIO as output with a value of 0.
+* GPIOD_OUT_HIGH to initialize the GPIO as output with a value of 1.
 
 Both functions return either a valid GPIO descriptor, or an error code checkable
 with IS_ERR() (they will never return a NULL pointer). -ENOENT will be returned
@@ -46,11 +57,13 @@ errors and an absence of GPIO for optional GPIO parameters.
 
 Device-managed variants of these functions are also defined:
 
-        struct gpio_desc *devm_gpiod_get(struct device *dev, const char *con_id)
+        struct gpio_desc *devm_gpiod_get(struct device *dev, const char *con_id,
+                                         enum gpiod_flags flags)
 
         struct gpio_desc *devm_gpiod_get_index(struct device *dev,
                                                const char *con_id,
-                                               unsigned int idx)
+                                               unsigned int idx,
+                                               enum gpiod_flags flags)
 
 A GPIO descriptor can be disposed of using the gpiod_put() function:
 
@@ -67,8 +80,9 @@ Using GPIOs
 
 Setting Direction
 -----------------
-The first thing a driver must do with a GPIO is setting its direction. This is
-done by invoking one of the gpiod_direction_*() functions:
+The first thing a driver must do with a GPIO is setting its direction. If no
+direction-setting flags have been given to gpiod_get*(), this is done by
+invoking one of the gpiod_direction_*() functions:
 
         int gpiod_direction_input(struct gpio_desc *desc)
         int gpiod_direction_output(struct gpio_desc *desc, int value)
diff --git a/Documentation/gpio/driver.txt b/Documentation/gpio/driver.txt
index fa9a0a8b3734..18790c237977 100644
--- a/Documentation/gpio/driver.txt
+++ b/Documentation/gpio/driver.txt
@@ -157,13 +157,34 @@ Locking IRQ usage
 Input GPIOs can be used as IRQ signals. When this happens, a driver is requested
 to mark the GPIO as being used as an IRQ:
 
-        int gpiod_lock_as_irq(struct gpio_desc *desc)
+        int gpio_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
 
 This will prevent the use of non-irq related GPIO APIs until the GPIO IRQ lock
 is released:
 
-        void gpiod_unlock_as_irq(struct gpio_desc *desc)
+        void gpio_unlock_as_irq(struct gpio_chip *chip, unsigned int offset)
 
 When implementing an irqchip inside a GPIO driver, these two functions should
 typically be called in the .startup() and .shutdown() callbacks from the
 irqchip.
+
+
+Requesting self-owned GPIO pins
+-------------------------------
+
+Sometimes it is useful to allow a GPIO chip driver to request its own GPIO
+descriptors through the gpiolib API. Using gpio_request() for this purpose
+does not help since it pins the module to the kernel forever (it calls
+try_module_get()). A GPIO driver can use the following functions instead
+to request and free descriptors without being pinned to the kernel forever.
+
+        int gpiochip_request_own_desc(struct gpio_desc *desc, const char *label)
+
+        void gpiochip_free_own_desc(struct gpio_desc *desc)
+
+Descriptors requested with gpiochip_request_own_desc() must be released with
+gpiochip_free_own_desc().
+
+These functions must be used with care since they do not affect module use
+count. Do not use the functions to request gpio descriptors not owned by the
+calling driver.