drivers: watchdog: add a CH32V00x Independent Watchdog (IWDT) driver (7f21dc2d) · Commits · Wenxi XU / zephyr

drivers/watchdog/CMakeLists.txt

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Changes for drivers/watchdog/CMakeLists.txt: 1 added line, 0 removed lines.
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		@@ -51,6 +51,7 @@ zephyr_library_sources_ifdef(CONFIG_WDT_AMBIQ wdt_ambiq.c)
		zephyr_library_sources_ifdef(CONFIG_WDT_XMC4XXX wdt_xmc4xxx.c)
		zephyr_library_sources_ifdef(CONFIG_WWDT_NUMAKER wdt_wwdt_numaker.c)
		zephyr_library_sources_ifdef(CONFIG_WDT_ENE_KB1200 wdt_ene_kb1200.c)
		zephyr_library_sources_ifdef(CONFIG_WDT_IWDG_WCH wdt_iwdg_wch.c)

		zephyr_library_sources_ifdef(CONFIG_WDT_DW wdt_dw.c wdt_dw_common.c)
		zephyr_library_sources_ifdef(CONFIG_WDT_INTEL_ADSP wdt_intel_adsp.c wdt_dw_common.c)

drivers/watchdog/Kconfig

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Changes for drivers/watchdog/Kconfig: 2 added lines, 0 removed lines.
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		@@ -151,4 +151,6 @@ source "drivers/watchdog/Kconfig.rts5912"

		source "drivers/watchdog/Kconfig.renesas_ra"

		source "drivers/watchdog/Kconfig.wch"

		endif # WATCHDOG

drivers/watchdog/Kconfig.wch

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Changes for drivers/watchdog/Kconfig.wch: 10 added lines, 0 removed lines.
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		# Copyright (c) 2025 Michael Hope <michaelh@juju.nz>
		# SPDX-License-Identifier: Apache-2.0

		config WDT_IWDG_WCH
		bool "WCH Independent Watchdog (IWDG) driver"
		default y
		depends on DT_HAS_WCH_IWDG_ENABLED
		help
		Enable the Independent Watchdog (IWDG) driver. Tested on the
		CH32V003 and CH32V208.

drivers/watchdog/wdt_iwdg_wch.c

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Changes for drivers/watchdog/wdt_iwdg_wch.c: 93 added lines, 0 removed lines.
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		/*
		* Copyright (c) 2025 Michael Hope <michaelh@juju.nz>
		*
		* SPDX-License-Identifier: Apache-2.0
		*/

		#define DT_DRV_COMPAT wch_iwdg

		#include <zephyr/drivers/watchdog.h>
		#include <zephyr/kernel.h>
		#include <zephyr/sys_clock.h>
		#include <errno.h>

		#include <ch32fun.h>

		static int iwdg_wch_setup(const struct device *dev, uint8_t options)
		{
		if (options != 0) {
		return -ENOTSUP;
		}

		IWDG->CTLR = CTLR_KEY_Enable;

		return 0;
		}

		static int iwdg_wch_disable(const struct device *dev)
		{
		return -EPERM;
		}

		static int iwdg_wch_install_timeout(const struct device *dev,
		const struct wdt_timeout_cfg *config)
		{
		int prescaler = 0;
		/* The IWDT is driven by the 128 kHz LSI oscillator with at least a /4 prescaler. */
		uint32_t lsi_frequency = DT_PROP(DT_NODELABEL(clk_lsi), clock_frequency);
		uint32_t reload = config->window.max * (lsi_frequency / 1000 / 4);

		if (config->callback != NULL) {
		return -ENOTSUP;
		}
		if (config->window.min != 0) {
		return -ENOTSUP;
		}
		if ((config->flags & WDT_FLAG_RESET_MASK) != WDT_FLAG_RESET_SOC) {
		return -ENOTSUP;
		}

		for (; reload > IWDG_RL && prescaler < IWDG_PR;) {
		prescaler++;
		reload /= 2;
		}
		if (reload > IWDG_RL) {
		/* The reload is too high even with the maximum prescaler */
		return -EINVAL;
		}

		/* Wait for the watchdog to be idle, unlock it, update, and wait for idle. */
		while ((IWDG->STATR & (IWDG_RVU \| IWDG_PVU)) != 0) {
		}

		IWDG->CTLR = IWDG_WriteAccess_Enable;
		IWDG->PSCR = prescaler;
		IWDG->RLDR = reload;

		while ((IWDG->STATR & (IWDG_RVU \| IWDG_PVU)) != 0) {
		}

		return 0;
		}

		static int iwdg_wch_feed(const struct device *dev, int channel_id)
		{
		IWDG->CTLR = CTLR_KEY_Reload;

		return 0;
		}

		static const struct wdt_driver_api iwdg_wch_api = {
		.setup = iwdg_wch_setup,
		.disable = iwdg_wch_disable,
		.install_timeout = iwdg_wch_install_timeout,
		.feed = iwdg_wch_feed,
		};

		static int iwdg_wch_init(const struct device *dev)
		{
		return 0;
		}

		DEVICE_DT_INST_DEFINE(0, iwdg_wch_init, NULL, NULL, NULL, PRE_KERNEL_1,
		CONFIG_KERNEL_INIT_PRIORITY_DEVICE, &iwdg_wch_api);

dts/bindings/watchdog/wch,iwdg.yaml

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Changes for dts/bindings/watchdog/wch,iwdg.yaml: 12 added lines, 0 removed lines.
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		# Copyright (c) 2025 Michael Hope <michaelh@juju.nz>
		# SPDX-License-Identifier: Apache-2.0

		description: WCH Independent Watchdog (IWDG)

		compatible: "wch,iwdg"

		include: base.yaml

		properties:
		reg:
		required: true

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