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authorLinus Torvalds2023-04-25 17:18:18 -0700
committerLinus Torvalds2023-04-25 17:18:18 -0700
commit2c96606a0f8b7900387dbeb6532b59527999834d (patch)
tree84772d9aa6951ca93d27b3ddc9bcb7c79bd7b554 /Documentation
parentd84955790e16588774c4365ba0d449e8a2aa46d8 (diff)
parent8a4adcf67a39b3f308bb8cf686e41c0e26aa12e8 (diff)
Merge tag 'gpio-updates-for-v6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux
Pull gpio updates from Bartosz Golaszewski: "We have some new drivers, significant refactoring of existing intel platforms, lots of improvements all around, mass conversion to using immutable irqchips by drivers that had not been converted individually yet and some changes in the core library code. Summary: New drivers: - add a driver for the Loongson GPIO controller - add a driver for the fxl6408 I2C GPIO expander - add a GPIO module containing code common for Intel Elkhart Lake and Merrifield platforms - add a driver for the Intel Elkhart Lake platform reusing the code from the intel tangier library GPIOLIB core: - GPIO ACPI improvements - simplify gpiochip_add_data_with_keys() fwnode handling - cleanup header inclusions (remove unneeded ones, order the rest alphabetically) - remove duplicate code (reuse krealloc() instead of open-coding it, drop a duplicated check in gpiod_find_and_request()) - reshuffle the code to remove unnecessary forward declarations - coding style cleanups and improvements - add a helper for accessing device fwnodes - small updates in docs Driver improvements: - convert all remaining GPIO irqchip drivers to using immutable irqchips - drop unnecessary of_match_ptr() macro expansions - shrink the code in gpio-merrifield significantly by reusing the code from gpio-tangier + minor tweaks to the driver code - remove MODULE_LICENSE() from drivers that can only be built-in - add device-tree support to gpio-loongson1 - use new regmap features in gpio-104-dio-48e and gpio-pcie-idio-24 - minor tweaks and fixes to gpio-xra1403, gpio-sim, gpio-tegra194, gpio-omap, gpio-aspeed, gpio-raspberrypi-exp - shrink code in gpio-ich and gpio-pxa - Kconfig tweak for gpio-pmic-eic-sprd" * tag 'gpio-updates-for-v6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (99 commits) gpio: gpiolib: Simplify gpiochip_add_data_with_key() fwnode gpiolib: Add gpiochip_set_data() helper gpiolib: Move gpiochip_get_data() higher in the code gpiolib: Check array_info for NULL only once in gpiod_get_array() gpiolib: Replace open coded krealloc() gpiolib: acpi: Add a ignore wakeup quirk for Clevo NL5xNU gpiolib: acpi: Move ACPI device NULL check to acpi_get_driver_gpio_data() gpiolib: acpi: use the fwnode in acpi_gpiochip_find() gpio: mm-lantiq: Fix typo in the newly added header filename sh: mach-x3proto: Add missing #include <linux/gpio/driver.h> powerpc/40x: Add missing select OF_GPIO_MM_GPIOCHIP gpio: xlp: Convert to immutable irq_chip gpio: xilinx: Convert to immutable irq_chip gpio: xgs-iproc: Convert to immutable irq_chip gpio: visconti: Convert to immutable irq_chip gpio: tqmx86: Convert to immutable irq_chip gpio: thunderx: Convert to immutable irq_chip gpio: stmpe: Convert to immutable irq_chip gpio: siox: Convert to immutable irq_chip gpio: rda: Convert to immutable irq_chip ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/admin-guide/gpio/sysfs.rst2
-rw-r--r--Documentation/devicetree/bindings/gpio/fcs,fxl6408.yaml58
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio.txt41
-rw-r--r--Documentation/devicetree/bindings/gpio/loongson,ls-gpio.yaml126
-rw-r--r--Documentation/devicetree/bindings/gpio/loongson,ls1x-gpio.yaml49
-rw-r--r--Documentation/driver-api/gpio/driver.rst8
-rw-r--r--Documentation/driver-api/gpio/legacy.rst23
-rw-r--r--Documentation/translations/zh_CN/driver-api/gpio/legacy.rst20
-rw-r--r--Documentation/translations/zh_TW/gpio.txt19
9 files changed, 267 insertions, 79 deletions
diff --git a/Documentation/admin-guide/gpio/sysfs.rst b/Documentation/admin-guide/gpio/sysfs.rst
index ec09ffd983e7..35171d15f78d 100644
--- a/Documentation/admin-guide/gpio/sysfs.rst
+++ b/Documentation/admin-guide/gpio/sysfs.rst
@@ -145,7 +145,7 @@ requested using gpio_request()::
/* export the GPIO to userspace */
int gpiod_export(struct gpio_desc *desc, bool direction_may_change);
- /* reverse gpio_export() */
+ /* reverse gpiod_export() */
void gpiod_unexport(struct gpio_desc *desc);
/* create a sysfs link to an exported GPIO node */
diff --git a/Documentation/devicetree/bindings/gpio/fcs,fxl6408.yaml b/Documentation/devicetree/bindings/gpio/fcs,fxl6408.yaml
new file mode 100644
index 000000000000..65b6970e42fb
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/fcs,fxl6408.yaml
@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/gpio/fcs,fxl6408.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Fairchild FXL6408 I2C GPIO Expander
+
+maintainers:
+ - Emanuele Ghidoli <emanuele.ghidoli@toradex.com>
+
+properties:
+ compatible:
+ enum:
+ - fcs,fxl6408
+
+ reg:
+ maxItems: 1
+
+ "#gpio-cells":
+ const: 2
+
+ gpio-controller: true
+
+ gpio-line-names:
+ minItems: 1
+ maxItems: 8
+
+patternProperties:
+ "^(hog-[0-9]+|.+-hog(-[0-9]+)?)$":
+ required:
+ - gpio-hog
+
+required:
+ - compatible
+ - reg
+ - gpio-controller
+ - "#gpio-cells"
+
+additionalProperties: false
+
+examples:
+ - |
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ gpio_expander_43: gpio-expander@43 {
+ compatible = "fcs,fxl6408";
+ reg = <0x43>;
+ gpio-controller;
+ #gpio-cells = <2>;
+ gpio-line-names = "Wi-Fi_W_DISABLE", "Wi-Fi_WKUP_WLAN",
+ "PWR_EN_+V3.3_WiFi_N", "PCIe_REF_CLK_EN",
+ "USB_RESET_N", "USB_BYPASS_N", "Wi-Fi_PDn",
+ "Wi-Fi_WKUP_BT";
+ };
+ };
diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt
index 5663e71b751f..d82c32217fff 100644
--- a/Documentation/devicetree/bindings/gpio/gpio.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio.txt
@@ -154,18 +154,35 @@ of the GPIOs that can't be used.
Optionally, a GPIO controller may have a "gpio-line-names" property. This is
an array of strings defining the names of the GPIO lines going out of the
-GPIO controller. This name should be the most meaningful producer name
-for the system, such as a rail name indicating the usage. Package names
-such as pin name are discouraged: such lines have opaque names (since they
-are by definition generic purpose) and such names are usually not very
-helpful. For example "MMC-CD", "Red LED Vdd" and "ethernet reset" are
-reasonable line names as they describe what the line is used for. "GPIO0"
-is not a good name to give to a GPIO line. Placeholders are discouraged:
-rather use the "" (blank string) if the use of the GPIO line is undefined
-in your design. The names are assigned starting from line offset 0 from
-left to right from the passed array. An incomplete array (where the number
-of passed named are less than ngpios) will still be used up until the last
-provided valid line index.
+GPIO controller.
+
+For lines which are routed to on-board devices, this name should be
+the most meaningful producer name for the system, such as a rail name
+indicating the usage. Package names, such as a pin name, are discouraged:
+such lines have opaque names (since they are by definition general-purpose)
+and such names are usually not very helpful. For example "MMC-CD", "Red LED
+Vdd" and "ethernet reset" are reasonable line names as they describe what
+the line is used for. "GPIO0" is not a good name to give to a GPIO line
+that is hard-wired to a specific device.
+
+However, in the case of lines that are routed to a general purpose header
+(e.g. the Raspberry Pi 40-pin header), and therefore are not hard-wired to
+specific devices, using a pin number or the names on the header is fine
+provided these are real (preferably unique) names. Using an SoC's pad name
+or package name, or names made up from kernel-internal software constructs,
+are strongly discouraged. For example "pin8 [gpio14/uart0_txd]" is fine
+if the board's documentation labels pin 8 as such. However "PortB_24" (an
+example of a name from an SoC's reference manual) would not be desirable.
+
+In either case placeholders are discouraged: rather use the "" (blank
+string) if the use of the GPIO line is undefined in your design. Ideally,
+try to add comments to the dts file describing the naming the convention
+you have chosen, and specifying from where the names are derived.
+
+The names are assigned starting from line offset 0, from left to right,
+from the passed array. An incomplete array (where the number of passed
+names is less than ngpios) will be used up until the last provided valid
+line index.
Example:
diff --git a/Documentation/devicetree/bindings/gpio/loongson,ls-gpio.yaml b/Documentation/devicetree/bindings/gpio/loongson,ls-gpio.yaml
new file mode 100644
index 000000000000..fb86e8ce6349
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/loongson,ls-gpio.yaml
@@ -0,0 +1,126 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/gpio/loongson,ls-gpio.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Loongson GPIO controller.
+
+maintainers:
+ - Yinbo Zhu <zhuyinbo@loongson.cn>
+
+properties:
+ compatible:
+ enum:
+ - loongson,ls2k-gpio
+ - loongson,ls7a-gpio
+
+ reg:
+ maxItems: 1
+
+ ngpios:
+ minimum: 1
+ maximum: 64
+
+ "#gpio-cells":
+ const: 2
+
+ gpio-controller: true
+
+ gpio-ranges: true
+
+ interrupts:
+ minItems: 1
+ maxItems: 64
+
+required:
+ - compatible
+ - reg
+ - ngpios
+ - "#gpio-cells"
+ - gpio-controller
+ - gpio-ranges
+ - interrupts
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+
+ gpio0: gpio@1fe00500 {
+ compatible = "loongson,ls2k-gpio";
+ reg = <0x1fe00500 0x38>;
+ ngpios = <64>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ gpio-ranges = <&pctrl 0 0 15>,
+ <&pctrl 16 16 15>,
+ <&pctrl 32 32 10>,
+ <&pctrl 44 44 20>;
+ interrupt-parent = <&liointc1>;
+ interrupts = <28 IRQ_TYPE_LEVEL_LOW>,
+ <29 IRQ_TYPE_LEVEL_LOW>,
+ <30 IRQ_TYPE_LEVEL_LOW>,
+ <30 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <26 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <>,
+ <>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>,
+ <27 IRQ_TYPE_LEVEL_LOW>;
+ };
diff --git a/Documentation/devicetree/bindings/gpio/loongson,ls1x-gpio.yaml b/Documentation/devicetree/bindings/gpio/loongson,ls1x-gpio.yaml
new file mode 100644
index 000000000000..1a472c05697c
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/loongson,ls1x-gpio.yaml
@@ -0,0 +1,49 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/gpio/loongson,ls1x-gpio.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Loongson-1 GPIO controller
+
+maintainers:
+ - Keguang Zhang <keguang.zhang@gmail.com>
+
+properties:
+ compatible:
+ const: loongson,ls1x-gpio
+
+ reg:
+ maxItems: 1
+
+ gpio-controller: true
+
+ "#gpio-cells":
+ const: 2
+
+ ngpios:
+ minimum: 1
+ maximum: 32
+
+required:
+ - compatible
+ - reg
+ - gpio-controller
+ - "#gpio-cells"
+ - ngpios
+
+additionalProperties: false
+
+examples:
+ - |
+ gpio0: gpio@1fd010c0 {
+ compatible = "loongson,ls1x-gpio";
+ reg = <0x1fd010c0 0x4>;
+
+ gpio-controller;
+ #gpio-cells = <2>;
+
+ ngpios = <32>;
+ };
+
+...
diff --git a/Documentation/driver-api/gpio/driver.rst b/Documentation/driver-api/gpio/driver.rst
index 6baaeab79534..bf6319cc531b 100644
--- a/Documentation/driver-api/gpio/driver.rst
+++ b/Documentation/driver-api/gpio/driver.rst
@@ -218,10 +218,10 @@ not support open drain/open source in hardware, the GPIO library will instead
use a trick: when a line is set as output, if the line is flagged as open
drain, and the IN output value is low, it will be driven low as usual. But
if the IN output value is set to high, it will instead *NOT* be driven high,
-instead it will be switched to input, as input mode is high impedance, thus
-achieving an "open drain emulation" of sorts: electrically the behaviour will
-be identical, with the exception of possible hardware glitches when switching
-the mode of the line.
+instead it will be switched to input, as input mode is an equivalent to
+high impedance, thus achieving an "open drain emulation" of sorts: electrically
+the behaviour will be identical, with the exception of possible hardware glitches
+when switching the mode of the line.
For open source configuration the same principle is used, just that instead
of actively driving the line low, it is set to input.
diff --git a/Documentation/driver-api/gpio/legacy.rst b/Documentation/driver-api/gpio/legacy.rst
index a0559d93efd1..78372853c6d4 100644
--- a/Documentation/driver-api/gpio/legacy.rst
+++ b/Documentation/driver-api/gpio/legacy.rst
@@ -238,8 +238,6 @@ setup or driver probe/teardown code, so this is an easy constraint.)::
## gpio_free_array()
gpio_free()
- gpio_set_debounce()
-
Claiming and Releasing GPIOs
@@ -716,27 +714,6 @@ gpiochip nodes (possibly in conjunction with schematics) to determine
the correct GPIO number to use for a given signal.
-Exporting from Kernel code
---------------------------
-Kernel code can explicitly manage exports of GPIOs which have already been
-requested using gpio_request()::
-
- /* export the GPIO to userspace */
- int gpio_export(unsigned gpio, bool direction_may_change);
-
- /* reverse gpio_export() */
- void gpio_unexport();
-
-After a kernel driver requests a GPIO, it may only be made available in
-the sysfs interface by gpio_export(). The driver can control whether the
-signal direction may change. This helps drivers prevent userspace code
-from accidentally clobbering important system state.
-
-This explicit exporting can help with debugging (by making some kinds
-of experiments easier), or can provide an always-there interface that's
-suitable for documenting as part of a board support package.
-
-
API Reference
=============
diff --git a/Documentation/translations/zh_CN/driver-api/gpio/legacy.rst b/Documentation/translations/zh_CN/driver-api/gpio/legacy.rst
index 74fa473bb504..84ce2322fdba 100644
--- a/Documentation/translations/zh_CN/driver-api/gpio/legacy.rst
+++ b/Documentation/translations/zh_CN/driver-api/gpio/legacy.rst
@@ -219,7 +219,6 @@ GPIO 值的命令需要等待其信息排到队首才发送命令,再获得其
## gpio_free_array()
gpio_free()
- gpio_set_debounce()
@@ -654,25 +653,6 @@ GPIO 控制器的路径类似 /sys/class/gpio/gpiochip42/ (对于从#42 GPIO
确定给定信号所用的 GPIO 编号。
-从内核代码中导出
-----------------
-
-内核代码可以明确地管理那些已通过 gpio_request()申请的 GPIO 的导出::
-
- /* 导出 GPIO 到用户空间 */
- int gpio_export(unsigned gpio, bool direction_may_change);
-
- /* gpio_export()的逆操作 */
- void gpio_unexport();
-
-在一个内核驱动申请一个 GPIO 之后,它可以通过 gpio_export()使其在 sysfs
-接口中可见。该驱动可以控制信号方向是否可修改。这有助于防止用户空间代码无意间
-破坏重要的系统状态。
-
-这个明确的导出有助于(通过使某些实验更容易来)调试,也可以提供一个始终存在的接口,
-与文档配合作为板级支持包的一部分。
-
-
API参考
=======
diff --git a/Documentation/translations/zh_TW/gpio.txt b/Documentation/translations/zh_TW/gpio.txt
index 1b986bbb0909..62e560ffe628 100644
--- a/Documentation/translations/zh_TW/gpio.txt
+++ b/Documentation/translations/zh_TW/gpio.txt
@@ -226,7 +226,6 @@ GPIO 值的命令需要等待其信息排到隊首才發送命令,再獲得其
## gpio_free_array()
gpio_free()
- gpio_set_debounce()
@@ -615,21 +614,3 @@ GPIO 控制器的路徑類似 /sys/class/gpio/gpiochip42/ (對於從#42 GPIO
固定的,例如在擴展卡上的 GPIO會根據所使用的主板或所在堆疊架構中其他的板子而
有所不同。在這種情況下,你可能需要使用 gpiochip 節點(儘可能地結合電路圖)來
確定給定信號所用的 GPIO 編號。
-
-
-從內核代碼中導出
--------------
-內核代碼可以明確地管理那些已通過 gpio_request()申請的 GPIO 的導出:
-
- /* 導出 GPIO 到用戶空間 */
- int gpio_export(unsigned gpio, bool direction_may_change);
-
- /* gpio_export()的逆操作 */
- void gpio_unexport();
-
-在一個內核驅動申請一個 GPIO 之後,它可以通過 gpio_export()使其在 sysfs
-接口中可見。該驅動可以控制信號方向是否可修改。這有助於防止用戶空間代碼無意間
-破壞重要的系統狀態。
-
-這個明確的導出有助於(通過使某些實驗更容易來)調試,也可以提供一個始終存在的接口,
-與文檔配合作爲板級支持包的一部分。