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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>
24
25
26
27
28
29
30static 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
38
39struct da9063_watchdog {
40 struct da9063 *da9063;
41 struct watchdog_device wdtdev;
42};
43
44static unsigned int da9063_wdt_timeout_to_sel(unsigned int secs)
45{
46 unsigned int i;
47
48 for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) {
49 if (wdt_timeout[i] >= secs)
50 return i;
51 }
52
53 return DA9063_TWDSCALE_MAX;
54}
55
56static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int regval)
57{
58 return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
59 DA9063_TWDSCALE_MASK, regval);
60}
61
62static int da9063_wdt_start(struct watchdog_device *wdd)
63{
64 struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
65 unsigned int selector;
66 int ret;
67
68 selector = da9063_wdt_timeout_to_sel(wdt->wdtdev.timeout);
69 ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
70 if (ret)
71 dev_err(wdt->da9063->dev, "Watchdog failed to start (err = %d)\n",
72 ret);
73
74 return ret;
75}
76
77static int da9063_wdt_stop(struct watchdog_device *wdd)
78{
79 struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
80 int ret;
81
82 ret = regmap_update_bits(wdt->da9063->regmap, DA9063_REG_CONTROL_D,
83 DA9063_TWDSCALE_MASK, DA9063_TWDSCALE_DISABLE);
84 if (ret)
85 dev_alert(wdt->da9063->dev, "Watchdog failed to stop (err = %d)\n",
86 ret);
87
88 return ret;
89}
90
91static int da9063_wdt_ping(struct watchdog_device *wdd)
92{
93 struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
94 int ret;
95
96 ret = regmap_write(wdt->da9063->regmap, DA9063_REG_CONTROL_F,
97 DA9063_WATCHDOG);
98 if (ret)
99 dev_alert(wdt->da9063->dev, "Failed to ping the watchdog (err = %d)\n",
100 ret);
101
102 return ret;
103}
104
105static int da9063_wdt_set_timeout(struct watchdog_device *wdd,
106 unsigned int timeout)
107{
108 struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
109 unsigned int selector;
110 int ret;
111
112 selector = da9063_wdt_timeout_to_sel(timeout);
113 ret = _da9063_wdt_set_timeout(wdt->da9063, selector);
114 if (ret)
115 dev_err(wdt->da9063->dev, "Failed to set watchdog timeout (err = %d)\n",
116 ret);
117 else
118 wdd->timeout = wdt_timeout[selector];
119
120 return ret;
121}
122
123static int da9063_wdt_restart(struct watchdog_device *wdd, unsigned long action,
124 void *data)
125{
126 struct da9063_watchdog *wdt = watchdog_get_drvdata(wdd);
127 int ret;
128
129 ret = regmap_write(wdt->da9063->regmap, DA9063_REG_CONTROL_F,
130 DA9063_SHUTDOWN);
131 if (ret)
132 dev_alert(wdt->da9063->dev, "Failed to shutdown (err = %d)\n",
133 ret);
134
135 return ret;
136}
137
138static const struct watchdog_info da9063_watchdog_info = {
139 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
140 .identity = "DA9063 Watchdog",
141};
142
143static 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,
150};
151
152static int da9063_wdt_probe(struct platform_device *pdev)
153{
154 struct da9063 *da9063;
155 struct da9063_watchdog *wdt;
156
157 if (!pdev->dev.parent)
158 return -EINVAL;
159
160 da9063 = dev_get_drvdata(pdev->dev.parent);
161 if (!da9063)
162 return -EINVAL;
163
164 wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
165 if (!wdt)
166 return -ENOMEM;
167
168 wdt->da9063 = da9063;
169
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;
177
178 wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS;
179
180 watchdog_set_restart_priority(&wdt->wdtdev, 128);
181
182 watchdog_set_drvdata(&wdt->wdtdev, wdt);
183
184 return devm_watchdog_register_device(&pdev->dev, &wdt->wdtdev);
185}
186
187static struct platform_driver da9063_wdt_driver = {
188 .probe = da9063_wdt_probe,
189 .driver = {
190 .name = DA9063_DRVNAME_WATCHDOG,
191 },
192};
193module_platform_driver(da9063_wdt_driver);
194
195MODULE_AUTHOR("Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>");
196MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063");
197MODULE_LICENSE("GPL");
198MODULE_ALIAS("platform:" DA9063_DRVNAME_WATCHDOG);
199
