Merge tag 'pwm/for-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux

Pull pwm updates from Uwe Kleine-König:
 "In addition to the usual mix of core cleanups, driver changes, minor
  fixes and device tree updates the highlight this cycle is Rust support
  for the core and a first Rust driver both provided by Michal
  Wilczynski.

  Michal wrote about these changes on

    https://mwilczynski.dev/posts/bringing-rust-to-the-pwm-subsystem/

  which is a nice read"

* tag 'pwm/for-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux: (22 commits)
  pwm: rzg2l-gpt: Allow checking period_tick cache value only if sibling channel is enabled
  pwm: bcm2835: Make sure the channel is enabled after pwm_request()
  pwm: mediatek: Make use of struct_size macro
  pwm: mediatek: Remove unneeded semicolon
  pwm: airoha: Add support for EN7581 SoC
  pwm: mediatek: Convert to waveform API
  pwm: max7360: Clean MAX7360 code
  pwm: Drop unused function pwm_apply_args()
  pwm: Use %u to printf unsigned int pwm_chip::npwm and pwm_chip::id
  pwm: Simplify printf to emit chip->npwm in $debugfs/pwm
  pwm: th1520: Use module_pwm_platform_driver! macro
  pwm: th1520: Fix clippy warning for redundant struct field init
  pwm: Fix Rust formatting
  dt-bindings: pwm: thead: Add T-HEAD TH1520 PWM controller
  pwm: Add Rust driver for T-HEAD TH1520 SoC
  rust: pwm: Fix broken intra-doc link
  rust: pwm: Drop wrapping of PWM polarity and state
  rust: pwm: Add module_pwm_platform_driver! macro
  rust: pwm: Add complete abstraction layer
  rust: pwm: Add Kconfig and basic data structures
  ...

Author: torvalds

Documentation/devicetree/bindings/pwm/thead,th1520-pwm.yaml

@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pwm/thead,th1520-pwm.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: T-HEAD TH1520 PWM controller
+
+maintainers:
+  - Michal Wilczynski <m.wilczynski@samsung.com>
+
+allOf:
+  - $ref: pwm.yaml#
+
+properties:
+  compatible:
+    const: thead,th1520-pwm
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: SoC PWM clock
+
+  "#pwm-cells":
+    const: 3
+
+required:
+  - compatible
+  - reg
+  - clocks
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/thead,th1520-clk-ap.h>
+    soc {
+      #address-cells = <2>;
+      #size-cells = <2>;
+      pwm@ffec01c000 {
+          compatible = "thead,th1520-pwm";
+          reg = <0xff 0xec01c000 0x0 0x4000>;
+          clocks = <&clk CLK_PWM>;
+          #pwm-cells = <3>;
+      };
+    };

MAINTAINERS

@@ -20871,6 +20871,14 @@ F:	include/linux/pwm.h
 F:	include/linux/pwm_backlight.h
 K:	pwm_(config|apply_might_sleep|apply_atomic|ops)
 
+PWM SUBSYSTEM BINDINGS [RUST]
+M:	Michal Wilczynski <m.wilczynski@samsung.com>
+L:	linux-pwm@vger.kernel.org
+L:	rust-for-linux@vger.kernel.org
+S:	Maintained
+F:	rust/helpers/pwm.c
+F:	rust/kernel/pwm.rs
+
 PXA GPIO DRIVER
 M:	Robert Jarzmik <robert.jarzmik@free.fr>
 L:	linux-gpio@vger.kernel.org
@@ -22293,6 +22301,7 @@ F:	Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml
 F:	Documentation/devicetree/bindings/mailbox/thead,th1520-mbox.yaml
 F:	Documentation/devicetree/bindings/net/thead,th1520-gmac.yaml
 F:	Documentation/devicetree/bindings/pinctrl/thead,th1520-pinctrl.yaml
+F:	Documentation/devicetree/bindings/pwm/thead,th1520-pwm.yaml
 F:	Documentation/devicetree/bindings/reset/thead,th1520-reset.yaml
 F:	arch/riscv/boot/dts/thead/
 F:	drivers/clk/thead/clk-th1520-ap.c
@@ -22303,6 +22312,7 @@ F:	drivers/pinctrl/pinctrl-th1520.c
 F:	drivers/pmdomain/thead/
 F:	drivers/power/reset/th1520-aon-reboot.c
 F:	drivers/power/sequencing/pwrseq-thead-gpu.c
+F:	drivers/pwm/pwm_th1520.rs
 F:	drivers/reset/reset-th1520.c
 F:	include/dt-bindings/clock/thead,th1520-clk-ap.h
 F:	include/dt-bindings/power/thead,th1520-power.h

drivers/pwm/Kconfig

@@ -63,6 +63,16 @@ config PWM_ADP5585
 	  This option enables support for the PWM function found in the Analog
 	  Devices ADP5585.
 
+config PWM_AIROHA
+	tristate "Airoha PWM support"
+	depends on ARCH_AIROHA || COMPILE_TEST
+	select REGMAP_MMIO
+	help
+	  Generic PWM framework driver for Airoha SoC.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-airoha.
+
 config PWM_APPLE
 	tristate "Apple SoC PWM support"
 	depends on ARCH_APPLE || COMPILE_TEST
@@ -748,6 +758,17 @@ config PWM_TEGRA
 	  To compile this driver as a module, choose M here: the module
 	  will be called pwm-tegra.
 
+config PWM_TH1520
+	tristate "TH1520 PWM support"
+	depends on RUST
+	select RUST_PWM_ABSTRACTIONS
+	help
+	  This option enables the driver for the PWM controller found on the
+	  T-HEAD TH1520 SoC.
+
+	  To compile this driver as a module, choose M here; the module
+	  will be called pwm-th1520. If you are unsure, say N.
+
 config PWM_TIECAP
 	tristate "ECAP PWM support"
 	depends on ARCH_OMAP2PLUS || ARCH_DAVINCI_DA8XX || ARCH_KEYSTONE || ARCH_K3 || COMPILE_TEST
@@ -819,4 +840,16 @@ config PWM_XILINX
 	  To compile this driver as a module, choose M here: the module
 	  will be called pwm-xilinx.
 
+ config RUST_PWM_ABSTRACTIONS
+	bool
+	depends on RUST
+	help
+	  This option enables the safe Rust abstraction layer for the PWM
+	  subsystem. It provides idiomatic wrappers and traits necessary for
+	  writing PWM controller drivers in Rust.
+
+	  The abstractions handle resource management (like memory and reference
+	  counting) and provide safe interfaces to the underlying C core,
+	  allowing driver logic to be written in safe Rust.
+
 endif

drivers/pwm/Makefile

@@ -2,6 +2,7 @@
 obj-$(CONFIG_PWM)		+= core.o
 obj-$(CONFIG_PWM_AB8500)	+= pwm-ab8500.o
 obj-$(CONFIG_PWM_ADP5585)	+= pwm-adp5585.o
+obj-$(CONFIG_PWM_AIROHA)	+= pwm-airoha.o
 obj-$(CONFIG_PWM_APPLE)		+= pwm-apple.o
 obj-$(CONFIG_PWM_ARGON_FAN_HAT)	+= pwm-argon-fan-hat.o
 obj-$(CONFIG_PWM_ATMEL)		+= pwm-atmel.o
@@ -68,6 +69,7 @@ obj-$(CONFIG_PWM_STMPE)		+= pwm-stmpe.o
 obj-$(CONFIG_PWM_SUN4I)		+= pwm-sun4i.o
 obj-$(CONFIG_PWM_SUNPLUS)	+= pwm-sunplus.o
 obj-$(CONFIG_PWM_TEGRA)		+= pwm-tegra.o
+obj-$(CONFIG_PWM_TH1520)	+= pwm_th1520.o
 obj-$(CONFIG_PWM_TIECAP)	+= pwm-tiecap.o
 obj-$(CONFIG_PWM_TIEHRPWM)	+= pwm-tiehrpwm.o
 obj-$(CONFIG_PWM_TWL)		+= pwm-twl.o

drivers/pwm/core.c

@@ -1608,12 +1608,13 @@ void pwmchip_put(struct pwm_chip *chip)
 }
 EXPORT_SYMBOL_GPL(pwmchip_put);
 
-static void pwmchip_release(struct device *pwmchip_dev)
+void pwmchip_release(struct device *pwmchip_dev)
 {
 	struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev);
 
 	kfree(chip);
 }
+EXPORT_SYMBOL_GPL(pwmchip_release);
 
 struct pwm_chip *pwmchip_alloc(struct device *parent, unsigned int npwm, size_t sizeof_priv)
 {
@@ -2696,11 +2697,10 @@ static int pwm_seq_show(struct seq_file *s, void *v)
 {
 	struct pwm_chip *chip = v;
 
-	seq_printf(s, "%s%d: %s/%s, %d PWM device%s\n",
+	seq_printf(s, "%s%u: %s/%s, npwm: %u\n",
 		   (char *)s->private, chip->id,
 		   pwmchip_parent(chip)->bus ? pwmchip_parent(chip)->bus->name : "no-bus",
-		   dev_name(pwmchip_parent(chip)), chip->npwm,
-		   (chip->npwm != 1) ? "s" : "");
+		   dev_name(pwmchip_parent(chip)), chip->npwm);
 
 	pwm_dbg_show(chip, s);