2 * Watchdog driver for DA9063 PMICs.
4 * Copyright(c) 2012 Dialog Semiconductor Ltd.
6 * Author: Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/watchdog.h>
17 #include <linux/platform_device.h>
18 #include <linux/uaccess.h>
19 #include <linux/slab.h>
20 #include <linux/delay.h>
21 #include <linux/mfd/da9063/registers.h>
22 #include <linux/mfd/da9063/core.h>
23 #include <linux/regmap.h>
26 * Watchdog selector to timeout in seconds.
28 * others: timeout = 2048 ms * 2^(TWDSCALE-1).
30 static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
31 #define DA9063_TWDSCALE_DISABLE 0
32 #define DA9063_TWDSCALE_MIN 1
33 #define DA9063_TWDSCALE_MAX (ARRAY_SIZE(wdt_timeout) - 1)
34 #define DA9063_WDT_MIN_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MIN]
35 #define DA9063_WDT_MAX_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MAX]
36 #define DA9063_WDG_TIMEOUT wdt_timeout[3]
37 #define DA9063_RESET_PROTECTION_MS 256
39 struct da9063_watchdog {
40 struct da9063 *da9063;
41 struct watchdog_device wdtdev;
44 static unsigned int da9063_wdt_timeout_to_sel(unsigned int secs)
48 for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) {
49 if (wdt_timeout[i] >= secs)
53 return DA9063_TWDSCALE_MAX;
56 static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int regval)
58 return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
59 DA9063_TWDSCALE_MASK, regval);
62 static int da9063_wdt_start(struct watchdog_device *wdd)
64 struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
65 unsigned int selector;
68 selector = da9063_wdt_timeout_to_sel(wdt->wdtdev.timeout);
69 ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
71 dev_err(wdt->da9063->dev, "Watchdog failed to start (err = %d)\n",
77 static int da9063_wdt_stop(struct watchdog_device *wdd)
79 struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
82 ret = regmap_update_bits(wdt->da9063->regmap, DA9063_REG_CONTROL_D,
83 DA9063_TWDSCALE_MASK, DA9063_TWDSCALE_DISABLE);
85 dev_alert(wdt->da9063->dev, "Watchdog failed to stop (err = %d)\n",
91 static int da9063_wdt_ping(struct watchdog_device *wdd)
93 struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
96 ret = regmap_write(wdt->da9063->regmap, DA9063_REG_CONTROL_F,
99 dev_alert(wdt->da9063->dev, "Failed to ping the watchdog (err = %d)\n",
105 static int da9063_wdt_set_timeout(struct watchdog_device *wdd,
106 unsigned int timeout)
108 struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
109 unsigned int selector;
112 selector = da9063_wdt_timeout_to_sel(timeout);
113 ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
115 dev_err(wdt->da9063->dev, "Failed to set watchdog timeout (err = %d)\n",
118 wdd->timeout = wdt_timeout[selector];
123 static int da9063_wdt_restart(struct watchdog_device *wdd, unsigned long action,
126 struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
129 ret = regmap_write(wdt->da9063->regmap, DA9063_REG_CONTROL_F,
132 dev_alert(wdt->da9063->dev, "Failed to shutdown (err = %d)\n",
138 static const struct watchdog_info da9063_watchdog_info = {
139 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
140 .identity = "DA9063 Watchdog",
143 static const struct watchdog_ops da9063_watchdog_ops = {
144 .owner = THIS_MODULE,
145 .start = da9063_wdt_start,
146 .stop = da9063_wdt_stop,
147 .ping = da9063_wdt_ping,
148 .set_timeout = da9063_wdt_set_timeout,
149 .restart = da9063_wdt_restart,
152 static int da9063_wdt_probe(struct platform_device *pdev)
154 struct da9063 *da9063;
155 struct da9063_watchdog *wdt;
157 if (!pdev->dev.parent)
160 da9063 = dev_get_drvdata(pdev->dev.parent);
164 wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
168 wdt->da9063 = da9063;
170 wdt->wdtdev.info = &da9063_watchdog_info;
171 wdt->wdtdev.ops = &da9063_watchdog_ops;
172 wdt->wdtdev.min_timeout = DA9063_WDT_MIN_TIMEOUT;
173 wdt->wdtdev.max_timeout = DA9063_WDT_MAX_TIMEOUT;
174 wdt->wdtdev.min_hw_heartbeat_ms = DA9063_RESET_PROTECTION_MS;
175 wdt->wdtdev.timeout = DA9063_WDG_TIMEOUT;
176 wdt->wdtdev.parent = &pdev->dev;
178 wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS;
180 watchdog_set_restart_priority(&wdt->wdtdev, 128);
182 watchdog_set_drvdata(&wdt->wdtdev, wdt);
184 return devm_watchdog_register_device(&pdev->dev, &wdt->wdtdev);
187 static struct platform_driver da9063_wdt_driver = {
188 .probe = da9063_wdt_probe,
190 .name = DA9063_DRVNAME_WATCHDOG,
193 module_platform_driver(da9063_wdt_driver);
195 MODULE_AUTHOR("Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>");
196 MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063");
197 MODULE_LICENSE("GPL");
198 MODULE_ALIAS("platform:" DA9063_DRVNAME_WATCHDOG);