Commit | Line | Data |
---|---|---|
2e62c498 | 1 | // SPDX-License-Identifier: GPL-2.0+ |
7a7cb009 | 2 | /* |
72106c18 | 3 | * Watchdog device driver for DA9062 and DA9061 PMICs |
7a7cb009 T |
4 | * Copyright (C) 2015 Dialog Semiconductor Ltd. |
5 | * | |
7a7cb009 T |
6 | */ |
7 | ||
8 | #include <linux/kernel.h> | |
9 | #include <linux/module.h> | |
10 | #include <linux/watchdog.h> | |
11 | #include <linux/platform_device.h> | |
12 | #include <linux/uaccess.h> | |
13 | #include <linux/slab.h> | |
057b52b4 | 14 | #include <linux/i2c.h> |
7a7cb009 T |
15 | #include <linux/delay.h> |
16 | #include <linux/jiffies.h> | |
17 | #include <linux/mfd/da9062/registers.h> | |
18 | #include <linux/mfd/da9062/core.h> | |
8541673d | 19 | #include <linux/property.h> |
7a7cb009 T |
20 | #include <linux/regmap.h> |
21 | #include <linux/of.h> | |
22 | ||
23 | static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 }; | |
24 | #define DA9062_TWDSCALE_DISABLE 0 | |
25 | #define DA9062_TWDSCALE_MIN 1 | |
26 | #define DA9062_TWDSCALE_MAX (ARRAY_SIZE(wdt_timeout) - 1) | |
27 | #define DA9062_WDT_MIN_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MIN] | |
28 | #define DA9062_WDT_MAX_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MAX] | |
29 | #define DA9062_WDG_DEFAULT_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MAX-1] | |
30 | #define DA9062_RESET_PROTECTION_MS 300 | |
31 | ||
32 | struct da9062_watchdog { | |
33 | struct da9062 *hw; | |
34 | struct watchdog_device wdtdev; | |
8541673d | 35 | bool use_sw_pm; |
7a7cb009 T |
36 | }; |
37 | ||
e8799ce8 SR |
38 | static unsigned int da9062_wdt_read_timeout(struct da9062_watchdog *wdt) |
39 | { | |
40 | unsigned int val; | |
41 | ||
42 | regmap_read(wdt->hw->regmap, DA9062AA_CONTROL_D, &val); | |
43 | ||
44 | return wdt_timeout[val & DA9062AA_TWDSCALE_MASK]; | |
45 | } | |
46 | ||
7a7cb009 T |
47 | static unsigned int da9062_wdt_timeout_to_sel(unsigned int secs) |
48 | { | |
49 | unsigned int i; | |
50 | ||
51 | for (i = DA9062_TWDSCALE_MIN; i <= DA9062_TWDSCALE_MAX; i++) { | |
52 | if (wdt_timeout[i] >= secs) | |
53 | return i; | |
54 | } | |
55 | ||
56 | return DA9062_TWDSCALE_MAX; | |
57 | } | |
58 | ||
59 | static int da9062_reset_watchdog_timer(struct da9062_watchdog *wdt) | |
60 | { | |
6e8a7c75 GR |
61 | return regmap_update_bits(wdt->hw->regmap, DA9062AA_CONTROL_F, |
62 | DA9062AA_WATCHDOG_MASK, | |
63 | DA9062AA_WATCHDOG_MASK); | |
7a7cb009 T |
64 | } |
65 | ||
66 | static int da9062_wdt_update_timeout_register(struct da9062_watchdog *wdt, | |
67 | unsigned int regval) | |
68 | { | |
69 | struct da9062 *chip = wdt->hw; | |
7a7cb009 | 70 | |
f31b2a9b MG |
71 | regmap_update_bits(chip->regmap, |
72 | DA9062AA_CONTROL_D, | |
73 | DA9062AA_TWDSCALE_MASK, | |
74 | DA9062_TWDSCALE_DISABLE); | |
75 | ||
76 | usleep_range(150, 300); | |
77 | ||
7a7cb009 T |
78 | return regmap_update_bits(chip->regmap, |
79 | DA9062AA_CONTROL_D, | |
80 | DA9062AA_TWDSCALE_MASK, | |
81 | regval); | |
82 | } | |
83 | ||
84 | static int da9062_wdt_start(struct watchdog_device *wdd) | |
85 | { | |
86 | struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); | |
87 | unsigned int selector; | |
88 | int ret; | |
89 | ||
90 | selector = da9062_wdt_timeout_to_sel(wdt->wdtdev.timeout); | |
91 | ret = da9062_wdt_update_timeout_register(wdt, selector); | |
92 | if (ret) | |
93 | dev_err(wdt->hw->dev, "Watchdog failed to start (err = %d)\n", | |
94 | ret); | |
95 | ||
96 | return ret; | |
97 | } | |
98 | ||
99 | static int da9062_wdt_stop(struct watchdog_device *wdd) | |
100 | { | |
101 | struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); | |
102 | int ret; | |
103 | ||
7a7cb009 T |
104 | ret = regmap_update_bits(wdt->hw->regmap, |
105 | DA9062AA_CONTROL_D, | |
106 | DA9062AA_TWDSCALE_MASK, | |
107 | DA9062_TWDSCALE_DISABLE); | |
108 | if (ret) | |
109 | dev_err(wdt->hw->dev, "Watchdog failed to stop (err = %d)\n", | |
110 | ret); | |
111 | ||
112 | return ret; | |
113 | } | |
114 | ||
115 | static int da9062_wdt_ping(struct watchdog_device *wdd) | |
116 | { | |
117 | struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); | |
118 | int ret; | |
119 | ||
2f61b3a7 PF |
120 | /* |
121 | * Prevent pings from occurring late in system poweroff/reboot sequence | |
122 | * and possibly locking out restart handler from accessing i2c bus. | |
123 | */ | |
124 | if (system_state > SYSTEM_RUNNING) | |
125 | return 0; | |
126 | ||
7a7cb009 T |
127 | ret = da9062_reset_watchdog_timer(wdt); |
128 | if (ret) | |
129 | dev_err(wdt->hw->dev, "Failed to ping the watchdog (err = %d)\n", | |
130 | ret); | |
131 | ||
132 | return ret; | |
133 | } | |
134 | ||
135 | static int da9062_wdt_set_timeout(struct watchdog_device *wdd, | |
136 | unsigned int timeout) | |
137 | { | |
138 | struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); | |
139 | unsigned int selector; | |
140 | int ret; | |
141 | ||
142 | selector = da9062_wdt_timeout_to_sel(timeout); | |
143 | ret = da9062_wdt_update_timeout_register(wdt, selector); | |
144 | if (ret) | |
145 | dev_err(wdt->hw->dev, "Failed to set watchdog timeout (err = %d)\n", | |
146 | ret); | |
147 | else | |
148 | wdd->timeout = wdt_timeout[selector]; | |
149 | ||
150 | return ret; | |
151 | } | |
152 | ||
540f6351 MG |
153 | static int da9062_wdt_restart(struct watchdog_device *wdd, unsigned long action, |
154 | void *data) | |
155 | { | |
156 | struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); | |
057b52b4 | 157 | struct i2c_client *client = to_i2c_client(wdt->hw->dev); |
540f6351 MG |
158 | int ret; |
159 | ||
057b52b4 MF |
160 | /* Don't use regmap because it is not atomic safe */ |
161 | ret = i2c_smbus_write_byte_data(client, DA9062AA_CONTROL_F, | |
162 | DA9062AA_SHUTDOWN_MASK); | |
163 | if (ret < 0) | |
540f6351 MG |
164 | dev_alert(wdt->hw->dev, "Failed to shutdown (err = %d)\n", |
165 | ret); | |
166 | ||
167 | /* wait for reset to assert... */ | |
168 | mdelay(500); | |
169 | ||
170 | return ret; | |
171 | } | |
172 | ||
7a7cb009 T |
173 | static const struct watchdog_info da9062_watchdog_info = { |
174 | .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, | |
175 | .identity = "DA9062 WDT", | |
176 | }; | |
177 | ||
178 | static const struct watchdog_ops da9062_watchdog_ops = { | |
179 | .owner = THIS_MODULE, | |
180 | .start = da9062_wdt_start, | |
181 | .stop = da9062_wdt_stop, | |
182 | .ping = da9062_wdt_ping, | |
183 | .set_timeout = da9062_wdt_set_timeout, | |
540f6351 | 184 | .restart = da9062_wdt_restart, |
7a7cb009 T |
185 | }; |
186 | ||
72106c18 ST |
187 | static const struct of_device_id da9062_compatible_id_table[] = { |
188 | { .compatible = "dlg,da9062-watchdog", }, | |
189 | { }, | |
190 | }; | |
191 | ||
192 | MODULE_DEVICE_TABLE(of, da9062_compatible_id_table); | |
193 | ||
7a7cb009 T |
194 | static int da9062_wdt_probe(struct platform_device *pdev) |
195 | { | |
6e8a7c75 | 196 | struct device *dev = &pdev->dev; |
e8799ce8 | 197 | unsigned int timeout; |
7a7cb009 T |
198 | struct da9062 *chip; |
199 | struct da9062_watchdog *wdt; | |
200 | ||
6e8a7c75 | 201 | chip = dev_get_drvdata(dev->parent); |
7a7cb009 T |
202 | if (!chip) |
203 | return -EINVAL; | |
204 | ||
6e8a7c75 | 205 | wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL); |
7a7cb009 T |
206 | if (!wdt) |
207 | return -ENOMEM; | |
208 | ||
8541673d MF |
209 | wdt->use_sw_pm = device_property_present(dev, "dlg,use-sw-pm"); |
210 | ||
7a7cb009 T |
211 | wdt->hw = chip; |
212 | ||
213 | wdt->wdtdev.info = &da9062_watchdog_info; | |
214 | wdt->wdtdev.ops = &da9062_watchdog_ops; | |
215 | wdt->wdtdev.min_timeout = DA9062_WDT_MIN_TIMEOUT; | |
216 | wdt->wdtdev.max_timeout = DA9062_WDT_MAX_TIMEOUT; | |
fb484262 | 217 | wdt->wdtdev.min_hw_heartbeat_ms = DA9062_RESET_PROTECTION_MS; |
7a7cb009 T |
218 | wdt->wdtdev.timeout = DA9062_WDG_DEFAULT_TIMEOUT; |
219 | wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS; | |
6e8a7c75 | 220 | wdt->wdtdev.parent = dev; |
7a7cb009 | 221 | |
540f6351 MG |
222 | watchdog_set_restart_priority(&wdt->wdtdev, 128); |
223 | ||
7a7cb009 | 224 | watchdog_set_drvdata(&wdt->wdtdev, wdt); |
f6c98b08 | 225 | dev_set_drvdata(dev, &wdt->wdtdev); |
7a7cb009 | 226 | |
e8799ce8 SR |
227 | timeout = da9062_wdt_read_timeout(wdt); |
228 | if (timeout) | |
229 | wdt->wdtdev.timeout = timeout; | |
230 | ||
231 | /* Set timeout from DT value if available */ | |
232 | watchdog_init_timeout(&wdt->wdtdev, 0, dev); | |
233 | ||
234 | if (timeout) { | |
235 | da9062_wdt_set_timeout(&wdt->wdtdev, wdt->wdtdev.timeout); | |
236 | set_bit(WDOG_HW_RUNNING, &wdt->wdtdev.status); | |
237 | } | |
7a7cb009 | 238 | |
e8799ce8 | 239 | return devm_watchdog_register_device(dev, &wdt->wdtdev); |
7a7cb009 T |
240 | } |
241 | ||
f6c98b08 MF |
242 | static int __maybe_unused da9062_wdt_suspend(struct device *dev) |
243 | { | |
244 | struct watchdog_device *wdd = dev_get_drvdata(dev); | |
8541673d MF |
245 | struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); |
246 | ||
247 | if (!wdt->use_sw_pm) | |
248 | return 0; | |
f6c98b08 MF |
249 | |
250 | if (watchdog_active(wdd)) | |
251 | return da9062_wdt_stop(wdd); | |
252 | ||
253 | return 0; | |
254 | } | |
255 | ||
256 | static int __maybe_unused da9062_wdt_resume(struct device *dev) | |
257 | { | |
258 | struct watchdog_device *wdd = dev_get_drvdata(dev); | |
8541673d MF |
259 | struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); |
260 | ||
261 | if (!wdt->use_sw_pm) | |
262 | return 0; | |
f6c98b08 MF |
263 | |
264 | if (watchdog_active(wdd)) | |
265 | return da9062_wdt_start(wdd); | |
266 | ||
267 | return 0; | |
268 | } | |
269 | ||
270 | static SIMPLE_DEV_PM_OPS(da9062_wdt_pm_ops, | |
271 | da9062_wdt_suspend, da9062_wdt_resume); | |
272 | ||
7a7cb009 T |
273 | static struct platform_driver da9062_wdt_driver = { |
274 | .probe = da9062_wdt_probe, | |
7a7cb009 T |
275 | .driver = { |
276 | .name = "da9062-watchdog", | |
f6c98b08 | 277 | .pm = &da9062_wdt_pm_ops, |
72106c18 | 278 | .of_match_table = da9062_compatible_id_table, |
7a7cb009 T |
279 | }, |
280 | }; | |
281 | module_platform_driver(da9062_wdt_driver); | |
282 | ||
283 | MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>"); | |
72106c18 | 284 | MODULE_DESCRIPTION("WDT device driver for Dialog DA9062 and DA9061"); |
7a7cb009 T |
285 | MODULE_LICENSE("GPL"); |
286 | MODULE_ALIAS("platform:da9062-watchdog"); |