drivers: pwm: rts5912: port pwm driver on Zephyr

Add PWM driver support for Realtek RTS5912

Signed-off-by: Titan Chen <titan.chen@realtek.com>

drivers/pwm/CMakeLists.txt

@@ -54,3 +54,4 @@ zephyr_library_sources_ifdef(CONFIG_PWM_RENESAS_RZ_GPT	pwm_renesas_rz_gpt.c)
 zephyr_library_sources_ifdef(CONFIG_USERSPACE   pwm_handlers.c)
 zephyr_library_sources_ifdef(CONFIG_PWM_CAPTURE pwm_capture.c)
 zephyr_library_sources_ifdef(CONFIG_PWM_SHELL   pwm_shell.c)
+zephyr_library_sources_ifdef(CONFIG_PWM_REALTEK_RTS5912 pwm_realtek_rts5912.c)

drivers/pwm/Kconfig

@@ -122,4 +122,6 @@ source "drivers/pwm/Kconfig.fake"
 
 source "drivers/pwm/Kconfig.renesas_rz"
 
+source "drivers/pwm/Kconfig.rts5912"
+
 endif # PWM

drivers/pwm/Kconfig.rts5912

@@ -0,0 +1,9 @@
+# Copyright (c) 2025, Realtek, SIBG-SD7
+# SPDX-License-Identifier: Apache-2.0
+
+config PWM_REALTEK_RTS5912
+	bool "Realtek RTS5912 PWM Driver"
+	default y
+	depends on DT_HAS_REALTEK_RTS5912_PWM_ENABLED
+	help
+	  Enable PWM driver for Realtek RTS5912 EC.

drivers/pwm/pwm_realtek_rts5912.c

@@ -0,0 +1,125 @@
+/*
+ * Copyright (c) 2025 Realtek, SIBG-SD7
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#define DT_DRV_COMPAT realtek_rts5912_pwm
+
+#include <zephyr/drivers/pwm.h>
+#include <zephyr/drivers/pinctrl.h>
+#include <zephyr/logging/log.h>
+#include <zephyr/drivers/clock_control.h>
+#include <zephyr/drivers/clock_control/clock_control_rts5912.h>
+
+#include "reg/reg_pwm.h"
+
+LOG_MODULE_REGISTER(pwm, CONFIG_PWM_LOG_LEVEL);
+
+#define PWM_CYCLE_PER_SEC MHZ(50)
+
+struct pwm_rts5912_config {
+	volatile struct pwm_regs *pwm_regs;
+	uint32_t pwm_clk_grp;
+	uint32_t pwm_clk_idx;
+	const struct device *clk_dev;
+	const struct pinctrl_dev_config *pcfg;
+};
+
+static int pwm_rts5912_set_cycles(const struct device *dev, uint32_t channel,
+				  uint32_t period_cycles, uint32_t pulse_cycles, pwm_flags_t flags)
+{
+	const struct pwm_rts5912_config *const pwm_config = dev->config;
+	volatile struct pwm_regs *pwm_regs = pwm_config->pwm_regs;
+
+	uint32_t pwm_div, pwm_duty;
+
+	if (channel > 0) {
+		return -EIO;
+	}
+
+	pwm_div = period_cycles;
+	pwm_duty = pulse_cycles;
+
+	pwm_regs->div = pwm_div;
+	pwm_regs->duty = pwm_duty;
+
+	LOG_DBG("period_cycles=%d, pulse_cycles=%d, pwm_div=%d, pwm_duty=%d", period_cycles,
+		pulse_cycles, pwm_div, pwm_duty);
+
+	if (flags == PWM_POLARITY_INVERTED) {
+		pwm_regs->ctrl |= PWM_CTRL_INVT;
+	}
+	pwm_regs->ctrl |= PWM_CTRL_EN;
+
+	return 0;
+}
+
+static int pwm_rts5912_get_cycles_per_sec(const struct device *dev, uint32_t channel,
+					  uint64_t *cycles)
+{
+	ARG_UNUSED(dev);
+
+	if (channel > 0) {
+		return -EIO;
+	}
+
+	if (cycles) {
+		*cycles = PWM_CYCLE_PER_SEC;
+	}
+
+	return 0;
+}
+
+static DEVICE_API(pwm, pwm_rts5912_driver_api) = {
+	.set_cycles = pwm_rts5912_set_cycles,
+	.get_cycles_per_sec = pwm_rts5912_get_cycles_per_sec,
+};
+
+static int pwm_rts5912_init(const struct device *dev)
+{
+	const struct pwm_rts5912_config *const pwm_config = dev->config;
+	struct rts5912_sccon_subsys sccon;
+
+	int rc = 0;
+#ifdef CONFIG_PINCTRL
+	rc = pinctrl_apply_state(pwm_config->pcfg, PINCTRL_STATE_DEFAULT);
+	if (rc < 0) {
+		LOG_ERR("PWM pinctrl setup failed (%d)", rc);
+		return rc;
+	}
+#endif
+#ifdef CONFIG_CLOCK_CONTROL
+	if (!device_is_ready(pwm_config->clk_dev)) {
+		return -ENODEV;
+	}
+
+	sccon.clk_grp = pwm_config->pwm_clk_grp;
+	sccon.clk_idx = pwm_config->pwm_clk_idx;
+	rc = clock_control_on(pwm_config->clk_dev, (clock_control_subsys_t)&sccon);
+	if (rc != 0) {
+		return rc;
+	}
+#endif
+	return rc;
+}
+
+#define RTS5912_PWM_PINCTRL_DEF(inst) PINCTRL_DT_INST_DEFINE(inst)
+
+#define RTS5912_PWM_CONFIG(inst)                                                                   \
+	static struct pwm_rts5912_config pwm_rts5912_config_##inst = {                             \
+		.pwm_regs = (struct pwm_regs *)DT_INST_REG_ADDR(inst),                             \
+		.pwm_clk_grp = DT_INST_CLOCKS_CELL(inst, clk_grp),                                 \
+		.pwm_clk_idx = DT_INST_CLOCKS_CELL(inst, clk_idx),                                 \
+		.clk_dev = DEVICE_DT_GET(DT_INST_CLOCKS_CTLR(inst)),                               \
+		.pcfg = PINCTRL_DT_INST_DEV_CONFIG_GET(inst),                                      \
+	};
+
+#define RTS5912_PWM_DEVICE_INIT(index)                                                             \
+	RTS5912_PWM_PINCTRL_DEF(index);                                                            \
+	RTS5912_PWM_CONFIG(index);                                                                 \
+	DEVICE_DT_INST_DEFINE(index, &pwm_rts5912_init, NULL, NULL, &pwm_rts5912_config_##index,   \
+			      POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE,                     \
+			      &pwm_rts5912_driver_api);
+
+DT_INST_FOREACH_STATUS_OKAY(RTS5912_PWM_DEVICE_INIT)

dts/arm/realtek/ec/rts5912.dtsi

@@ -9,6 +9,7 @@
 #include <zephyr/dt-bindings/adc/adc.h>
 #include <zephyr/dt-bindings/clock/rts5912_clock.h>
 #include <zephyr/dt-bindings/gpio/realtek-gpio.h>
+#include <zephyr/dt-bindings/pwm/pwm.h>
 
 / {
 	cpus {
@@ -364,6 +365,70 @@
 			interrupts = <192 0>;
 			status = "disabled";
 		};
+
+		pwm0: pwm@4000f000 {
+			compatible = "realtek,rts5912-pwm";
+			clocks = <&sccon RTS5912_SCCON_PERIPH_GRP0 PERIPH_GRP0_PWM0_CLKPWR>;
+			reg = <0x4000f000 0x0c>;
+			status = "disabled";
+			#pwm-cells = <3>;
+		};
+
+		pwm1: pwm@4000f00c {
+			compatible = "realtek,rts5912-pwm";
+			clocks = <&sccon RTS5912_SCCON_PERIPH_GRP0 PERIPH_GRP0_PWM1_CLKPWR>;
+			reg = <0x4000f00c 0x0c>;
+			status = "disabled";
+			#pwm-cells = <3>;
+		};
+
+		pwm2: pwm@4000f018 {
+			compatible = "realtek,rts5912-pwm";
+			clocks = <&sccon RTS5912_SCCON_PERIPH_GRP0 PERIPH_GRP0_PWM2_CLKPWR>;
+			reg = <0x4000f018 0x0c>;
+			status = "disabled";
+			#pwm-cells = <3>;
+		};
+
+		pwm3: pwm@4000f024 {
+			compatible = "realtek,rts5912-pwm";
+			clocks = <&sccon RTS5912_SCCON_PERIPH_GRP0 PERIPH_GRP0_PWM3_CLKPWR>;
+			reg = <0x4000f024 0x0c>;
+			status = "disabled";
+			#pwm-cells = <3>;
+		};
+
+		pwm4: pwm@4000f030 {
+			compatible = "realtek,rts5912-pwm";
+			clocks = <&sccon RTS5912_SCCON_PERIPH_GRP0 PERIPH_GRP0_PWM4_CLKPWR>;
+			reg = <0x4000f030 0x0c>;
+			status = "disabled";
+			#pwm-cells = <3>;
+		};
+
+		pwm5: pwm@4000f03c {
+			compatible = "realtek,rts5912-pwm";
+			clocks = <&sccon RTS5912_SCCON_PERIPH_GRP0 PERIPH_GRP0_PWM5_CLKPWR>;
+			reg = <0x4000f03c 0x0c>;
+			status = "disabled";
+			#pwm-cells = <3>;
+		};
+
+		pwm6: pwm@4000f048 {
+			compatible = "realtek,rts5912-pwm";
+			clocks = <&sccon RTS5912_SCCON_PERIPH_GRP0 PERIPH_GRP0_PWM6_CLKPWR>;
+			reg = <0x4000f048 0x0c>;
+			status = "disabled";
+			#pwm-cells = <3>;
+		};
+
+		pwm7: pwm@4000f054 {
+			compatible = "realtek,rts5912-pwm";
+			clocks = <&sccon RTS5912_SCCON_PERIPH_GRP0 PERIPH_GRP0_PWM7_CLKPWR>;
+			reg = <0x4000f054 0x0c>;
+			status = "disabled";
+			#pwm-cells = <3>;
+		};
 	};
 
 	swj_port: swj-port {

dts/bindings/pwm/realtek,rts5912-pwm.yaml

@@ -0,0 +1,20 @@
+# Copyright (c) 2025, Realtek, SIBG-SD7
+# SPDX-License-Identifier: Apache-2.0
+
+description: Realtek RTS5912 PWM
+
+include: [pwm-controller.yaml, base.yaml, pinctrl-device.yaml]
+
+compatible: "realtek,rts5912-pwm"
+
+properties:
+  reg:
+    required: true
+
+  "#pwm-cells":
+    const: 3
+
+pwm-cells:
+  - channel
+  - period
+  - flags

soc/realtek/ec/rts5912/reg/reg_pwm.h

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2025 Realtek, SIBG-SD7
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef ZEPHYR_SOC_REALTEK_RTS5912_REG_PWM_H
+#define ZEPHYR_SOC_REALTEK_RTS5912_REG_PWM_H
+
+/*
+ * @brief PWM Controller (PWM)
+ */
+
+struct pwm_regs {
+	uint32_t duty;
+	uint32_t div;
+	uint32_t ctrl;
+};
+
+/* CTRL */
+#define PWM_CTRL_CLKSRC BIT(28)
+#define PWM_CTRL_INVT   BIT(29)
+#define PWM_CTRL_RST    BIT(30)
+#define PWM_CTRL_EN     BIT(31)
+
+#endif /* ZEPHYR_SOC_REALTEK_RTS5912_REG_PWM_H */

tests/drivers/build_all/pwm/boards/rts5912_evb.overlay

@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2025 Realtek Corporation. All Rights Reserved.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/ {
+	aliases {
+		pwm-0 = &pwm0;
+	};
+};
+
+&pwm0 {
+	status = "okay";
+};

tests/drivers/build_all/pwm/testcase.yaml

@@ -57,3 +57,5 @@ tests:
   drivers.pwm.max31790.build:
     platform_allow: nucleo_f429zi
     extra_args: DTC_OVERLAY_FILE=max31790.overlay
+  drivers.pwm.rts5912.build:
+    platform_allow: rts5912_evb