1 // SPDX-License-Identifier: GPL-2.0+
3  * Watchdog driver for DA9063 PMICs.
13 #include <linux/watchdog.h>
19 #include <linux/mfd/da9063/registers.h>
20 #include <linux/mfd/da9063/core.h>
25  * Watchdog selector to timeout in seconds.
27  *   others: timeout = 2048 ms * 2^(TWDSCALE-1).
33 #define DA9063_TWDSCALE_MAX		(ARRAY_SIZE(wdt_timeout) - 1)
53  * Zero means the watchdog is disabled.
55 static unsigned int da9063_wdt_read_timeout(struct da9063 *da9063)  in da9063_wdt_read_timeout()  argument
59 	regmap_read(da9063->regmap, DA9063_REG_CONTROL_D, &val);  in da9063_wdt_read_timeout()
64 static int da9063_wdt_disable_timer(struct da9063 *da9063)  in da9063_wdt_disable_timer()  argument
66 	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,  in da9063_wdt_disable_timer()
72 da9063_wdt_update_timeout(struct da9063 *da9063, unsigned int timeout)  in da9063_wdt_update_timeout()  argument
78 	 * The watchdog triggers a reboot if a timeout value is already  in da9063_wdt_update_timeout()
80 	 * in one: indicating the counter limit and starting the watchdog.  in da9063_wdt_update_timeout()
81 	 * The watchdog must be disabled to be able to change the timeout  in da9063_wdt_update_timeout()
82 	 * value if the watchdog is already running. Then we can set the  in da9063_wdt_update_timeout()
83 	 * new timeout value which enables the watchdog again.  in da9063_wdt_update_timeout()
85 	ret = da9063_wdt_disable_timer(da9063);  in da9063_wdt_update_timeout()
92 	return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,  in da9063_wdt_update_timeout()
98 	struct da9063 *da9063 = watchdog_get_drvdata(wdd);  in da9063_wdt_start()  local
101 	ret = da9063_wdt_update_timeout(da9063, wdd->timeout);  in da9063_wdt_start()
103 		dev_err(da9063->dev, "Watchdog failed to start (err = %d)\n",  in da9063_wdt_start()
111 	struct da9063 *da9063 = watchdog_get_drvdata(wdd);  in da9063_wdt_stop()  local
114 	ret = da9063_wdt_disable_timer(da9063);  in da9063_wdt_stop()
116 		dev_alert(da9063->dev, "Watchdog failed to stop (err = %d)\n",  in da9063_wdt_stop()
124 	struct da9063 *da9063 = watchdog_get_drvdata(wdd);  in da9063_wdt_ping()  local
134 	ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,  in da9063_wdt_ping()
137 		dev_alert(da9063->dev, "Failed to ping the watchdog (err = %d)\n",  in da9063_wdt_ping()
146 	struct da9063 *da9063 = watchdog_get_drvdata(wdd);  in da9063_wdt_set_timeout()  local
151 	 * 1. The watchdog is off and someone wants to set the timeout for the  in da9063_wdt_set_timeout()
153 	 * 2. The watchdog is already running and a new timeout value should be  in da9063_wdt_set_timeout()
156 	 * The watchdog can't store a timeout value not equal zero without  in da9063_wdt_set_timeout()
157 	 * enabling the watchdog, so the timeout must be buffered by the driver.  in da9063_wdt_set_timeout()
160 		ret = da9063_wdt_update_timeout(da9063, timeout);  in da9063_wdt_set_timeout()
163 		dev_err(da9063->dev, "Failed to set watchdog timeout (err = %d)\n",  in da9063_wdt_set_timeout()
166 		wdd->timeout = wdt_timeout[da9063_wdt_timeout_to_sel(timeout)];  in da9063_wdt_set_timeout()
174 	struct da9063 *da9063 = watchdog_get_drvdata(wdd);  in da9063_wdt_restart()  local
175 	struct i2c_client *client = to_i2c_client(da9063->dev);  in da9063_wdt_restart()
186 	ret = __i2c_smbus_xfer(client->adapter, client->addr, client->flags,  in da9063_wdt_restart()
191 		dev_alert(da9063->dev, "Failed to shutdown (err = %d)\n",  in da9063_wdt_restart()
202 	.identity = "DA9063 Watchdog",
216 	struct device *dev = &pdev->dev;  in da9063_wdt_probe()
217 	struct da9063 *da9063;  in da9063_wdt_probe()  local
221 	if (!dev->parent)  in da9063_wdt_probe()
222 		return -EINVAL;  in da9063_wdt_probe()
224 	da9063 = dev_get_drvdata(dev->parent);  in da9063_wdt_probe()
225 	if (!da9063)  in da9063_wdt_probe()
226 		return -EINVAL;  in da9063_wdt_probe()
230 		return -ENOMEM;  in da9063_wdt_probe()
232 	da9063->use_sw_pm = device_property_present(dev, "dlg,use-sw-pm");  in da9063_wdt_probe()
234 	wdd->info = &da9063_watchdog_info;  in da9063_wdt_probe()
235 	wdd->ops = &da9063_watchdog_ops;  in da9063_wdt_probe()
236 	wdd->min_timeout = DA9063_WDT_MIN_TIMEOUT;  in da9063_wdt_probe()
237 	wdd->max_timeout = DA9063_WDT_MAX_TIMEOUT;  in da9063_wdt_probe()
238 	wdd->min_hw_heartbeat_ms = DA9063_RESET_PROTECTION_MS;  in da9063_wdt_probe()
239 	wdd->parent = dev;  in da9063_wdt_probe()
240 	wdd->status = WATCHDOG_NOWAYOUT_INIT_STATUS;  in da9063_wdt_probe()
243 	watchdog_set_drvdata(wdd, da9063);  in da9063_wdt_probe()
246 	wdd->timeout = DA9063_WDG_TIMEOUT;  in da9063_wdt_probe()
248 	/* Use pre-configured timeout if watchdog is already running. */  in da9063_wdt_probe()
249 	timeout = da9063_wdt_read_timeout(da9063);  in da9063_wdt_probe()
251 		wdd->timeout = timeout;  in da9063_wdt_probe()
255 	da9063_wdt_set_timeout(wdd, wdd->timeout);  in da9063_wdt_probe()
257 	/* Update timeout if the watchdog is already running. */  in da9063_wdt_probe()
259 		da9063_wdt_update_timeout(da9063, wdd->timeout);  in da9063_wdt_probe()
260 		set_bit(WDOG_HW_RUNNING, &wdd->status);  in da9063_wdt_probe()
269 	struct da9063 *da9063 = watchdog_get_drvdata(wdd);  in da9063_wdt_suspend()  local
271 	if (!da9063->use_sw_pm)  in da9063_wdt_suspend()
283 	struct da9063 *da9063 = watchdog_get_drvdata(wdd);  in da9063_wdt_resume()  local
285 	if (!da9063->use_sw_pm)  in da9063_wdt_resume()
307 MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063");