Commit | Line | Data |
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d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
eca10ae6 | 2 | /* |
766a2aad | 3 | * Watchdog driver for Faraday Technology FTWDT010 |
eca10ae6 LW |
4 | * |
5 | * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org> | |
6 | * | |
7 | * Inspired by the out-of-tree drivers from OpenWRT: | |
8 | * Copyright (C) 2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt> | |
eca10ae6 LW |
9 | */ |
10 | ||
11 | #include <linux/bitops.h> | |
12 | #include <linux/init.h> | |
13 | #include <linux/interrupt.h> | |
14 | #include <linux/io.h> | |
15 | #include <linux/kernel.h> | |
16 | #include <linux/module.h> | |
17 | #include <linux/of_device.h> | |
18 | #include <linux/platform_device.h> | |
19 | #include <linux/slab.h> | |
20 | #include <linux/watchdog.h> | |
21 | ||
766a2aad LW |
22 | #define FTWDT010_WDCOUNTER 0x0 |
23 | #define FTWDT010_WDLOAD 0x4 | |
24 | #define FTWDT010_WDRESTART 0x8 | |
25 | #define FTWDT010_WDCR 0xC | |
eca10ae6 LW |
26 | |
27 | #define WDRESTART_MAGIC 0x5AB9 | |
28 | ||
29 | #define WDCR_CLOCK_5MHZ BIT(4) | |
d5433fd6 LW |
30 | #define WDCR_WDEXT BIT(3) |
31 | #define WDCR_WDINTR BIT(2) | |
eca10ae6 LW |
32 | #define WDCR_SYS_RST BIT(1) |
33 | #define WDCR_ENABLE BIT(0) | |
34 | ||
35 | #define WDT_CLOCK 5000000 /* 5 MHz */ | |
36 | ||
766a2aad | 37 | struct ftwdt010_wdt { |
eca10ae6 LW |
38 | struct watchdog_device wdd; |
39 | struct device *dev; | |
40 | void __iomem *base; | |
d5433fd6 | 41 | bool has_irq; |
eca10ae6 LW |
42 | }; |
43 | ||
44 | static inline | |
766a2aad | 45 | struct ftwdt010_wdt *to_ftwdt010_wdt(struct watchdog_device *wdd) |
eca10ae6 | 46 | { |
766a2aad | 47 | return container_of(wdd, struct ftwdt010_wdt, wdd); |
eca10ae6 LW |
48 | } |
49 | ||
766a2aad | 50 | static int ftwdt010_wdt_start(struct watchdog_device *wdd) |
eca10ae6 | 51 | { |
766a2aad | 52 | struct ftwdt010_wdt *gwdt = to_ftwdt010_wdt(wdd); |
d5433fd6 | 53 | u32 enable; |
eca10ae6 | 54 | |
766a2aad LW |
55 | writel(wdd->timeout * WDT_CLOCK, gwdt->base + FTWDT010_WDLOAD); |
56 | writel(WDRESTART_MAGIC, gwdt->base + FTWDT010_WDRESTART); | |
eca10ae6 | 57 | /* set clock before enabling */ |
d5433fd6 LW |
58 | enable = WDCR_CLOCK_5MHZ | WDCR_SYS_RST; |
59 | writel(enable, gwdt->base + FTWDT010_WDCR); | |
60 | if (gwdt->has_irq) | |
61 | enable |= WDCR_WDINTR; | |
62 | enable |= WDCR_ENABLE; | |
63 | writel(enable, gwdt->base + FTWDT010_WDCR); | |
eca10ae6 LW |
64 | |
65 | return 0; | |
66 | } | |
67 | ||
766a2aad | 68 | static int ftwdt010_wdt_stop(struct watchdog_device *wdd) |
eca10ae6 | 69 | { |
766a2aad | 70 | struct ftwdt010_wdt *gwdt = to_ftwdt010_wdt(wdd); |
eca10ae6 | 71 | |
766a2aad | 72 | writel(0, gwdt->base + FTWDT010_WDCR); |
eca10ae6 LW |
73 | |
74 | return 0; | |
75 | } | |
76 | ||
766a2aad | 77 | static int ftwdt010_wdt_ping(struct watchdog_device *wdd) |
eca10ae6 | 78 | { |
766a2aad | 79 | struct ftwdt010_wdt *gwdt = to_ftwdt010_wdt(wdd); |
eca10ae6 | 80 | |
766a2aad | 81 | writel(WDRESTART_MAGIC, gwdt->base + FTWDT010_WDRESTART); |
eca10ae6 LW |
82 | |
83 | return 0; | |
84 | } | |
85 | ||
766a2aad | 86 | static int ftwdt010_wdt_set_timeout(struct watchdog_device *wdd, |
eca10ae6 LW |
87 | unsigned int timeout) |
88 | { | |
89 | wdd->timeout = timeout; | |
90 | if (watchdog_active(wdd)) | |
766a2aad | 91 | ftwdt010_wdt_start(wdd); |
eca10ae6 LW |
92 | |
93 | return 0; | |
94 | } | |
95 | ||
766a2aad | 96 | static irqreturn_t ftwdt010_wdt_interrupt(int irq, void *data) |
eca10ae6 | 97 | { |
766a2aad | 98 | struct ftwdt010_wdt *gwdt = data; |
eca10ae6 LW |
99 | |
100 | watchdog_notify_pretimeout(&gwdt->wdd); | |
101 | ||
102 | return IRQ_HANDLED; | |
103 | } | |
104 | ||
766a2aad LW |
105 | static const struct watchdog_ops ftwdt010_wdt_ops = { |
106 | .start = ftwdt010_wdt_start, | |
107 | .stop = ftwdt010_wdt_stop, | |
108 | .ping = ftwdt010_wdt_ping, | |
109 | .set_timeout = ftwdt010_wdt_set_timeout, | |
eca10ae6 LW |
110 | .owner = THIS_MODULE, |
111 | }; | |
112 | ||
766a2aad | 113 | static const struct watchdog_info ftwdt010_wdt_info = { |
eca10ae6 LW |
114 | .options = WDIOF_KEEPALIVEPING |
115 | | WDIOF_MAGICCLOSE | |
116 | | WDIOF_SETTIMEOUT, | |
117 | .identity = KBUILD_MODNAME, | |
118 | }; | |
119 | ||
120 | ||
766a2aad | 121 | static int ftwdt010_wdt_probe(struct platform_device *pdev) |
eca10ae6 LW |
122 | { |
123 | struct device *dev = &pdev->dev; | |
766a2aad | 124 | struct ftwdt010_wdt *gwdt; |
eca10ae6 LW |
125 | unsigned int reg; |
126 | int irq; | |
127 | int ret; | |
128 | ||
129 | gwdt = devm_kzalloc(dev, sizeof(*gwdt), GFP_KERNEL); | |
130 | if (!gwdt) | |
131 | return -ENOMEM; | |
132 | ||
0f0a6a28 | 133 | gwdt->base = devm_platform_ioremap_resource(pdev, 0); |
eca10ae6 LW |
134 | if (IS_ERR(gwdt->base)) |
135 | return PTR_ERR(gwdt->base); | |
136 | ||
eca10ae6 | 137 | gwdt->dev = dev; |
766a2aad LW |
138 | gwdt->wdd.info = &ftwdt010_wdt_info; |
139 | gwdt->wdd.ops = &ftwdt010_wdt_ops; | |
eca10ae6 LW |
140 | gwdt->wdd.min_timeout = 1; |
141 | gwdt->wdd.max_timeout = 0xFFFFFFFF / WDT_CLOCK; | |
142 | gwdt->wdd.parent = dev; | |
143 | ||
144 | /* | |
145 | * If 'timeout-sec' unspecified in devicetree, assume a 13 second | |
146 | * default. | |
147 | */ | |
148 | gwdt->wdd.timeout = 13U; | |
149 | watchdog_init_timeout(&gwdt->wdd, 0, dev); | |
150 | ||
766a2aad | 151 | reg = readw(gwdt->base + FTWDT010_WDCR); |
eca10ae6 LW |
152 | if (reg & WDCR_ENABLE) { |
153 | /* Watchdog was enabled by the bootloader, disable it. */ | |
154 | reg &= ~WDCR_ENABLE; | |
766a2aad | 155 | writel(reg, gwdt->base + FTWDT010_WDCR); |
eca10ae6 LW |
156 | } |
157 | ||
d5433fd6 LW |
158 | irq = platform_get_irq(pdev, 0); |
159 | if (irq) { | |
160 | ret = devm_request_irq(dev, irq, ftwdt010_wdt_interrupt, 0, | |
161 | "watchdog bark", gwdt); | |
162 | if (ret) | |
163 | return ret; | |
164 | gwdt->has_irq = true; | |
165 | } | |
eca10ae6 LW |
166 | |
167 | ret = devm_watchdog_register_device(dev, &gwdt->wdd); | |
2d065d2e | 168 | if (ret) |
eca10ae6 | 169 | return ret; |
eca10ae6 LW |
170 | |
171 | /* Set up platform driver data */ | |
172 | platform_set_drvdata(pdev, gwdt); | |
766a2aad | 173 | dev_info(dev, "FTWDT010 watchdog driver enabled\n"); |
eca10ae6 LW |
174 | |
175 | return 0; | |
176 | } | |
177 | ||
766a2aad | 178 | static int __maybe_unused ftwdt010_wdt_suspend(struct device *dev) |
eca10ae6 | 179 | { |
766a2aad | 180 | struct ftwdt010_wdt *gwdt = dev_get_drvdata(dev); |
eca10ae6 LW |
181 | unsigned int reg; |
182 | ||
766a2aad | 183 | reg = readw(gwdt->base + FTWDT010_WDCR); |
eca10ae6 | 184 | reg &= ~WDCR_ENABLE; |
766a2aad | 185 | writel(reg, gwdt->base + FTWDT010_WDCR); |
eca10ae6 LW |
186 | |
187 | return 0; | |
188 | } | |
189 | ||
766a2aad | 190 | static int __maybe_unused ftwdt010_wdt_resume(struct device *dev) |
eca10ae6 | 191 | { |
766a2aad | 192 | struct ftwdt010_wdt *gwdt = dev_get_drvdata(dev); |
eca10ae6 LW |
193 | unsigned int reg; |
194 | ||
195 | if (watchdog_active(&gwdt->wdd)) { | |
766a2aad | 196 | reg = readw(gwdt->base + FTWDT010_WDCR); |
eca10ae6 | 197 | reg |= WDCR_ENABLE; |
766a2aad | 198 | writel(reg, gwdt->base + FTWDT010_WDCR); |
eca10ae6 LW |
199 | } |
200 | ||
201 | return 0; | |
202 | } | |
203 | ||
766a2aad LW |
204 | static const struct dev_pm_ops ftwdt010_wdt_dev_pm_ops = { |
205 | SET_SYSTEM_SLEEP_PM_OPS(ftwdt010_wdt_suspend, | |
206 | ftwdt010_wdt_resume) | |
eca10ae6 LW |
207 | }; |
208 | ||
209 | #ifdef CONFIG_OF | |
766a2aad LW |
210 | static const struct of_device_id ftwdt010_wdt_match[] = { |
211 | { .compatible = "faraday,ftwdt010" }, | |
eca10ae6 LW |
212 | { .compatible = "cortina,gemini-watchdog" }, |
213 | {}, | |
214 | }; | |
766a2aad | 215 | MODULE_DEVICE_TABLE(of, ftwdt010_wdt_match); |
eca10ae6 LW |
216 | #endif |
217 | ||
766a2aad LW |
218 | static struct platform_driver ftwdt010_wdt_driver = { |
219 | .probe = ftwdt010_wdt_probe, | |
eca10ae6 | 220 | .driver = { |
766a2aad LW |
221 | .name = "ftwdt010-wdt", |
222 | .of_match_table = of_match_ptr(ftwdt010_wdt_match), | |
223 | .pm = &ftwdt010_wdt_dev_pm_ops, | |
eca10ae6 LW |
224 | }, |
225 | }; | |
766a2aad | 226 | module_platform_driver(ftwdt010_wdt_driver); |
eca10ae6 | 227 | MODULE_AUTHOR("Linus Walleij"); |
766a2aad | 228 | MODULE_DESCRIPTION("Watchdog driver for Faraday Technology FTWDT010"); |
eca10ae6 | 229 | MODULE_LICENSE("GPL"); |