Merge tag 'gpio-v5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v5.6 kernel cycle.

  This is a pretty calm cycle so far, nothing special going on really.
  Some more changes will come in from the irqchip and pin control trees.

  I also deleted an orphan include file for FMC that was dangling since
  subsystem was removed.

  Core changes:

   - Document the usecases for the kernelspace vs userspace handling of
     GPIOs.

   - Handle MSI (message signalled interrupts) properly in the core
     hierarchical irqdomain code.

   - Fix a rare race condition while initializing the descriptor array.

  New drivers:

   - Xylon LogiCVC GPIO driver.

   - WDC934x GPIO controller driver.

  Driver improvements:

   - Implemented suspend/resume in the Tegra driver.

   - MPC8xx edge detection fixup.

   - Properly convert ThunderX to use hierarchical irqdomain with
     GPIOLIB_IRQCHIP on top of the revert of the previous buggy
     switchover. This time it works (hopefully).

  Misc:

   - Drop a FMC remnant file <linux/ipmi-fru.h>

   - A slew of fixes"

* tag 'gpio-v5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (48 commits)
  MAINTAINERS: Replace Tien Hock Loh as Altera PIO maintainer
  gpiolib: hold gpio devices lock until ->descs array is initialised
  gpio: aspeed-sgpio: fixed typos
  gpio: mvebu: clear irq in edge cause register before unmask edge irq
  gpiolib: Lower verbosity when allocating hierarchy irq
  gpiolib: Remove duplicated function gpio_do_set_config()
  gpio: Fix the no return statement warning
  gpio: wcd934x: Add support to wcd934x gpio controller
  gpiolib: remove set but not used variable 'config'
  gpio: vx855: fixed a typo
  gpio: mockup: sort headers alphabetically
  gpio: mockup: update the license tag
  gpio: Remove the unused flags
  gpiolib: Set lockdep class for hierarchical irq domains
  gpio: thunderx: Switch to GPIOLIB_IRQCHIP
  gpiolib: Add the support for the msi parent domain
  gpiolib: Add support for the irqdomain which doesn't use irq_fwspec as arg
  gpio: Add use guidance documentation
  dt-bindings: gpio: wcd934x: Add bindings for gpio
  gpio: altera: change to platform_get_irq_optional to avoid false-positive error
  ...

Author: torvalds

Documentation/devicetree/bindings/gpio/qcom,wcd934x-gpio.yaml

@@ -0,0 +1,47 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/gpio/qcom,wcd934x-gpio.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: WCD9340/WCD9341 GPIO controller
+
+maintainers:
+  - Srinivas Kandagatla <[email protected]>
+
+description: |
+  Qualcomm Technologies Inc WCD9340/WCD9341 Audio Codec has integrated
+  gpio controller to control 5 gpios on the chip.
+
+properties:
+  compatible:
+    enum:
+      - qcom,wcd9340-gpio
+      - qcom,wcd9341-gpio
+
+  reg:
+    maxItems: 1
+
+  gpio-controller: true
+
+  '#gpio-cells':
+    const: 2
+
+required:
+  - compatible
+  - reg
+  - gpio-controller
+  - "#gpio-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    wcdgpio: gpio@42 {
+        compatible = "qcom,wcd9340-gpio";
+        reg = <0x042 0x2>;
+        gpio-controller;
+        #gpio-cells = <2>;
+    };
+
+...

Documentation/devicetree/bindings/gpio/renesas,gpio-rcar.txt

@@ -18,7 +18,8 @@ Required Properties:
     - "renesas,gpio-r8a7793": for R8A7793 (R-Car M2-N) compatible GPIO controller.
     - "renesas,gpio-r8a7794": for R8A7794 (R-Car E2) compatible GPIO controller.
     - "renesas,gpio-r8a7795": for R8A7795 (R-Car H3) compatible GPIO controller.
-    - "renesas,gpio-r8a7796": for R8A7796 (R-Car M3-W) compatible GPIO controller.
+    - "renesas,gpio-r8a7796": for R8A77960 (R-Car M3-W) compatible GPIO controller.
+    - "renesas,gpio-r8a77961": for R8A77961 (R-Car M3-W+) compatible GPIO controller.
     - "renesas,gpio-r8a77965": for R8A77965 (R-Car M3-N) compatible GPIO controller.
     - "renesas,gpio-r8a77970": for R8A77970 (R-Car V3M) compatible GPIO controller.
     - "renesas,gpio-r8a77980": for R8A77980 (R-Car V3H) compatible GPIO controller.

Documentation/devicetree/bindings/gpio/xylon,logicvc-gpio.yaml

@@ -0,0 +1,69 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2019 Bootlin
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/gpio/xylon,logicvc-gpio.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Xylon LogiCVC GPIO controller
+
+maintainers:
+  - Paul Kocialkowski <[email protected]>
+
+description: |
+  The LogiCVC GPIO describes the GPIO block included in the LogiCVC display
+  controller. These are meant to be used for controlling display-related
+  signals.
+
+  The controller exposes GPIOs from the display and power control registers,
+  which are mapped by the driver as follows:
+  - GPIO[4:0] (display control) mapped to index 0-4
+  - EN_BLIGHT (power control) mapped to index 5
+  - EN_VDD (power control) mapped to index 6
+  - EN_VEE (power control) mapped to index 7
+  - V_EN (power control) mapped to index 8
+
+properties:
+  $nodename:
+    pattern: "^gpio@[0-9a-f]+$"
+
+  compatible:
+    enum:
+      - xylon,logicvc-3.02.a-gpio
+
+  reg:
+    maxItems: 1
+
+  "#gpio-cells":
+    const: 2
+
+  gpio-controller: true
+
+  gpio-line-names:
+    minItems: 1
+    maxItems: 9
+
+required:
+  - compatible
+  - reg
+  - "#gpio-cells"
+  - gpio-controller
+
+examples:
+  - |
+    logicvc: logicvc@43c00000 {
+      compatible = "xylon,logicvc-3.02.a", "syscon", "simple-mfd";
+      reg = <0x43c00000 0x6000>;
+
+      #address-cells = <1>;
+      #size-cells = <1>;
+
+      logicvc_gpio: gpio@40 {
+        compatible = "xylon,logicvc-3.02.a-gpio";
+        reg = <0x40 0x40>;
+        gpio-controller;
+        #gpio-cells = <2>;
+        gpio-line-names = "GPIO0", "GPIO1", "GPIO2", "GPIO3", "GPIO4",
+               "EN_BLIGHT", "EN_VDD", "EN_VEE", "V_EN";
+      };
+    };

Documentation/devicetree/bindings/mfd/xylon,logicvc.yaml

@@ -0,0 +1,50 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2019 Bootlin
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/mfd/xylon,logicvc.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Xylon LogiCVC multi-function device
+
+maintainers:
+  - Paul Kocialkowski <[email protected]>
+
+description: |
+  The LogiCVC is a display controller that also contains a GPIO controller.
+  As a result, a multi-function device is exposed as parent of the display
+  and GPIO blocks.
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - xylon,logicvc-3.02.a
+      - const: syscon
+      - const: simple-mfd
+
+  reg:
+    maxItems: 1
+
+select:
+  properties:
+    compatible:
+      contains:
+        enum:
+          - xylon,logicvc-3.02.a
+
+  required:
+    - compatible
+
+required:
+  - compatible
+  - reg
+
+examples:
+  - |
+    logicvc: logicvc@43c00000 {
+      compatible = "xylon,logicvc-3.02.a", "syscon", "simple-mfd";
+      reg = <0x43c00000 0x6000>;
+      #address-cells = <1>;
+      #size-cells = <1>;
+    };

Documentation/devicetree/bindings/vendor-prefixes.yaml

@@ -1060,6 +1060,8 @@ patternProperties:
     description: Xilinx
   "^xunlong,.*":
     description: Shenzhen Xunlong Software CO.,Limited
+  "^xylon,.*":
+    description: Xylon
   "^yones-toptech,.*":
     description: Yones Toptech Co., Ltd.
   "^ysoft,.*":

Documentation/driver-api/driver-model/devres.rst

@@ -267,6 +267,8 @@ DRM
 
 GPIO
   devm_gpiod_get()
+  devm_gpiod_get_array()
+  devm_gpiod_get_array_optional()
   devm_gpiod_get_index()
   devm_gpiod_get_index_optional()
   devm_gpiod_get_optional()

Documentation/driver-api/gpio/drivers-on-gpio.rst

@@ -95,7 +95,7 @@ to emulate MCTRL (modem control) signals CTS/RTS by using two GPIO lines. The
 MTD NOR flash has add-ons for extra GPIO lines too, though the address bus is
 usually connected directly to the flash.
 
-Use those instead of talking directly to the GPIOs using sysfs; they integrate
-with kernel frameworks better than your userspace code could. Needless to say,
-just using the appropriate kernel drivers will simplify and speed up your
-embedded hacking in particular by providing ready-made components.
+Use those instead of talking directly to the GPIOs from userspace; they
+integrate with kernel frameworks better than your userspace code could.
+Needless to say, just using the appropriate kernel drivers will simplify and
+speed up your embedded hacking in particular by providing ready-made components.

Documentation/driver-api/gpio/index.rst

@@ -8,6 +8,7 @@ Contents:
    :maxdepth: 2
 
    intro
+   using-gpio
    driver
    consumer
    board

Documentation/driver-api/gpio/using-gpio.rst

@@ -0,0 +1,50 @@
+=========================
+Using GPIO Lines in Linux
+=========================
+
+The Linux kernel exists to abstract and present hardware to users. GPIO lines
+as such are normally not user facing abstractions. The most obvious, natural
+and preferred way to use GPIO lines is to let kernel hardware drivers deal
+with them.
+
+For examples of already existing generic drivers that will also be good
+examples for any other kernel drivers you want to author, refer to
+:doc:`drivers-on-gpio`
+
+For any kind of mass produced system you want to support, such as servers,
+laptops, phones, tablets, routers, and any consumer or office or business goods
+using appropriate kernel drivers is paramount. Submit your code for inclusion
+in the upstream Linux kernel when you feel it is mature enough and you will get
+help to refine it, see :doc:`../../process/submitting-patches`.
+
+In Linux GPIO lines also have a userspace ABI.
+
+The userspace ABI is intended for one-off deployments. Examples are prototypes,
+factory lines, maker community projects, workshop specimen, production tools,
+industrial automation, PLC-type use cases, door controllers, in short a piece
+of specialized equipment that is not produced by the numbers, requiring
+operators to have a deep knowledge of the equipment and knows about the
+software-hardware interface to be set up. They should not have a natural fit
+to any existing kernel subsystem and not be a good fit for an operating system,
+because of not being reusable or abstract enough, or involving a lot of non
+computer hardware related policy.
+
+Applications that have a good reason to use the industrial I/O (IIO) subsystem
+from userspace will likely be a good fit for using GPIO lines from userspace as
+well.
+
+Do not under any circumstances abuse the GPIO userspace ABI to cut corners in
+any product development projects. If you use it for prototyping, then do not
+productify the prototype: rewrite it using proper kernel drivers. Do not under
+any circumstances deploy any uniform products using GPIO from userspace.
+
+The userspace ABI is a character device for each GPIO hardware unit (GPIO chip).
+These devices will appear on the system as ``/dev/gpiochip0`` thru
+``/dev/gpiochipN``. Examples of how to directly use the userspace ABI can be
+found in the kernel tree ``tools/gpio`` subdirectory.
+
+For structured and managed applications, we recommend that you make use of the
+libgpiod_ library. This provides helper abstractions, command line utlities
+and arbitration for multiple simultaneous consumers on the same GPIO chip.
+
+.. _libgpiod: https://git.kernel.org/pub/scm/libs/libgpiod/libgpiod.git/

MAINTAINERS

@@ -734,7 +734,7 @@ S:	Maintained
 F:	drivers/mailbox/mailbox-altera.c
 
 ALTERA PIO DRIVER
-M:	Tien Hock Loh <thloh@altera.com>
+M:	Joyce Ooi <joyce.ooi@intel.com>
 L:	[email protected]
 S:	Maintained
 F:	drivers/gpio/gpio-altera.c