1 // SPDX-License-Identifier: GPL-2.0+
3  * Watchdog driver for DA9063 PMICs.
13 #include <linux/watchdog.h>
23  * Watchdog selector to timeout in seconds.
25  *   others: timeout = 2048 ms * 2^(TWDSCALE-1).
30 #define DA9063_TWDSCALE_MAX		(ARRAY_SIZE(wdt_timeout) - 1)
49  * Read the currently active timeout.
50  * Zero means the watchdog is disabled.
56 	regmap_read(da9063->regmap, DA9063_REG_CONTROL_D, &val);  in da9063_wdt_read_timeout()
63 	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,  in da9063_wdt_disable_timer()
69 da9063_wdt_update_timeout(struct da9063 *da9063, unsigned int timeout)  in da9063_wdt_update_timeout()  argument
75 	 * The watchdog triggers a reboot if a timeout value is already  in da9063_wdt_update_timeout()
76 	 * programmed because the timeout value combines two functions  in da9063_wdt_update_timeout()
77 	 * in one: indicating the counter limit and starting the watchdog.  in da9063_wdt_update_timeout()
78 	 * The watchdog must be disabled to be able to change the timeout  in da9063_wdt_update_timeout()
79 	 * value if the watchdog is already running. Then we can set the  in da9063_wdt_update_timeout()
80 	 * new timeout value which enables the watchdog again.  in da9063_wdt_update_timeout()
87 	regval = da9063_wdt_timeout_to_sel(timeout);  in da9063_wdt_update_timeout()
89 	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,  in da9063_wdt_update_timeout()
98 	ret = da9063_wdt_update_timeout(da9063, wdd->timeout);  in da9063_wdt_start()
100 		dev_err(da9063->dev, "Watchdog failed to start (err = %d)\n",  in da9063_wdt_start()
113 		dev_alert(da9063->dev, "Watchdog failed to stop (err = %d)\n",  in da9063_wdt_stop()
124 	ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,  in da9063_wdt_ping()
127 		dev_alert(da9063->dev, "Failed to ping the watchdog (err = %d)\n",  in da9063_wdt_ping()
134 				  unsigned int timeout)  in da9063_wdt_set_timeout()  argument
141 	 * 1. The watchdog is off and someone wants to set the timeout for the  in da9063_wdt_set_timeout()
143 	 * 2. The watchdog is already running and a new timeout value should be  in da9063_wdt_set_timeout()
146 	 * The watchdog can't store a timeout value not equal zero without  in da9063_wdt_set_timeout()
147 	 * enabling the watchdog, so the timeout must be buffered by the driver.  in da9063_wdt_set_timeout()
150 		ret = da9063_wdt_update_timeout(da9063, timeout);  in da9063_wdt_set_timeout()
153 		dev_err(da9063->dev, "Failed to set watchdog timeout (err = %d)\n",  in da9063_wdt_set_timeout()
156 		wdd->timeout = wdt_timeout[da9063_wdt_timeout_to_sel(timeout)];  in da9063_wdt_set_timeout()
167 	ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,  in da9063_wdt_restart()
170 		dev_alert(da9063->dev, "Failed to shutdown (err = %d)\n",  in da9063_wdt_restart()
178 	.identity = "DA9063 Watchdog",
192 	struct device *dev = &pdev->dev;  in da9063_wdt_probe()
195 	unsigned int timeout;  in da9063_wdt_probe()  local
197 	if (!dev->parent)  in da9063_wdt_probe()
198 		return -EINVAL;  in da9063_wdt_probe()
200 	da9063 = dev_get_drvdata(dev->parent);  in da9063_wdt_probe()
202 		return -EINVAL;  in da9063_wdt_probe()
206 		return -ENOMEM;  in da9063_wdt_probe()
208 	wdd->info = &da9063_watchdog_info;  in da9063_wdt_probe()
209 	wdd->ops = &da9063_watchdog_ops;  in da9063_wdt_probe()
210 	wdd->min_timeout = DA9063_WDT_MIN_TIMEOUT;  in da9063_wdt_probe()
211 	wdd->max_timeout = DA9063_WDT_MAX_TIMEOUT;  in da9063_wdt_probe()
212 	wdd->min_hw_heartbeat_ms = DA9063_RESET_PROTECTION_MS;  in da9063_wdt_probe()
213 	wdd->parent = dev;  in da9063_wdt_probe()
214 	wdd->status = WATCHDOG_NOWAYOUT_INIT_STATUS;  in da9063_wdt_probe()
219 	wdd->timeout = DA9063_WDG_TIMEOUT;  in da9063_wdt_probe()
221 	/* Use pre-configured timeout if watchdog is already running. */  in da9063_wdt_probe()
222 	timeout = da9063_wdt_read_timeout(da9063);  in da9063_wdt_probe()
223 	if (timeout)  in da9063_wdt_probe()
224 		wdd->timeout = timeout;  in da9063_wdt_probe()
226 	/* Set timeout, maybe override it with DT value, scale it */  in da9063_wdt_probe()
228 	da9063_wdt_set_timeout(wdd, wdd->timeout);  in da9063_wdt_probe()
230 	/* Update timeout if the watchdog is already running. */  in da9063_wdt_probe()
231 	if (timeout) {  in da9063_wdt_probe()
232 		da9063_wdt_update_timeout(da9063, wdd->timeout);  in da9063_wdt_probe()
233 		set_bit(WDOG_HW_RUNNING, &wdd->status);  in da9063_wdt_probe()
248 MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063");