Commit | Line | Data |
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f52ac8fe AZ |
1 | /* |
2 | * Watchdog driver for Cirrus Logic EP93xx family of devices. | |
3 | * | |
4 | * Copyright (c) 2004 Ray Lehtiniemi | |
5 | * Copyright (c) 2006 Tower Technologies | |
6 | * Based on ep93xx driver, bits from alim7101_wdt.c | |
7 | * | |
8 | * Authors: Ray Lehtiniemi <rayl@mail.com>, | |
9 | * Alessandro Zummo <a.zummo@towertech.it> | |
10 | * | |
e12a679d HS |
11 | * Copyright (c) 2012 H Hartley Sweeten <hsweeten@visionengravers.com> |
12 | * Convert to a platform device and use the watchdog framework API | |
13 | * | |
f52ac8fe AZ |
14 | * This file is licensed under the terms of the GNU General Public |
15 | * License version 2. This program is licensed "as is" without any | |
16 | * warranty of any kind, whether express or implied. | |
17 | * | |
18 | * This watchdog fires after 250msec, which is a too short interval | |
19 | * for us to rely on the user space daemon alone. So we ping the | |
20 | * wdt each ~200msec and eventually stop doing it if the user space | |
21 | * daemon dies. | |
f52ac8fe AZ |
22 | */ |
23 | ||
3e0113a8 | 24 | #include <linux/platform_device.h> |
f52ac8fe | 25 | #include <linux/module.h> |
f52ac8fe | 26 | #include <linux/watchdog.h> |
2653d1d7 | 27 | #include <linux/io.h> |
f52ac8fe | 28 | |
f52ac8fe AZ |
29 | /* default timeout (secs) */ |
30 | #define WDT_TIMEOUT 30 | |
31 | ||
86a1e189 | 32 | static bool nowayout = WATCHDOG_NOWAYOUT; |
e12a679d HS |
33 | module_param(nowayout, bool, 0); |
34 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"); | |
35 | ||
91700361 | 36 | static unsigned int timeout; |
2ca16063 | 37 | module_param(timeout, uint, 0); |
91700361 | 38 | MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds."); |
f52ac8fe | 39 | |
3e0113a8 HS |
40 | #define EP93XX_WATCHDOG 0x00 |
41 | #define EP93XX_WDSTATUS 0x04 | |
f52ac8fe | 42 | |
91700361 HS |
43 | struct ep93xx_wdt_priv { |
44 | void __iomem *mmio; | |
45 | struct watchdog_device wdd; | |
46 | }; | |
f52ac8fe | 47 | |
e12a679d | 48 | static int ep93xx_wdt_start(struct watchdog_device *wdd) |
f52ac8fe | 49 | { |
91700361 | 50 | struct ep93xx_wdt_priv *priv = watchdog_get_drvdata(wdd); |
f52ac8fe | 51 | |
91700361 | 52 | writel(0xaaaa, priv->mmio + EP93XX_WATCHDOG); |
e12a679d HS |
53 | |
54 | return 0; | |
f52ac8fe AZ |
55 | } |
56 | ||
e12a679d | 57 | static int ep93xx_wdt_stop(struct watchdog_device *wdd) |
f52ac8fe | 58 | { |
91700361 HS |
59 | struct ep93xx_wdt_priv *priv = watchdog_get_drvdata(wdd); |
60 | ||
61 | writel(0xaa55, priv->mmio + EP93XX_WATCHDOG); | |
e12a679d HS |
62 | |
63 | return 0; | |
f52ac8fe AZ |
64 | } |
65 | ||
91700361 | 66 | static int ep93xx_wdt_ping(struct watchdog_device *wdd) |
f52ac8fe | 67 | { |
91700361 HS |
68 | struct ep93xx_wdt_priv *priv = watchdog_get_drvdata(wdd); |
69 | ||
70 | writel(0x5555, priv->mmio + EP93XX_WATCHDOG); | |
f52ac8fe | 71 | |
e12a679d | 72 | return 0; |
f52ac8fe AZ |
73 | } |
74 | ||
e12a679d HS |
75 | static const struct watchdog_info ep93xx_wdt_ident = { |
76 | .options = WDIOF_CARDRESET | | |
91700361 | 77 | WDIOF_SETTIMEOUT | |
e12a679d HS |
78 | WDIOF_MAGICCLOSE | |
79 | WDIOF_KEEPALIVEPING, | |
80 | .identity = "EP93xx Watchdog", | |
f52ac8fe AZ |
81 | }; |
82 | ||
b893e344 | 83 | static const struct watchdog_ops ep93xx_wdt_ops = { |
f52ac8fe | 84 | .owner = THIS_MODULE, |
e12a679d HS |
85 | .start = ep93xx_wdt_start, |
86 | .stop = ep93xx_wdt_stop, | |
91700361 | 87 | .ping = ep93xx_wdt_ping, |
f52ac8fe AZ |
88 | }; |
89 | ||
2d991a16 | 90 | static int ep93xx_wdt_probe(struct platform_device *pdev) |
f52ac8fe | 91 | { |
d6ab0510 | 92 | struct device *dev = &pdev->dev; |
91700361 HS |
93 | struct ep93xx_wdt_priv *priv; |
94 | struct watchdog_device *wdd; | |
3e0113a8 | 95 | unsigned long val; |
91700361 HS |
96 | int ret; |
97 | ||
d6ab0510 | 98 | priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); |
91700361 HS |
99 | if (!priv) |
100 | return -ENOMEM; | |
f52ac8fe | 101 | |
0f0a6a28 | 102 | priv->mmio = devm_platform_ioremap_resource(pdev, 0); |
91700361 HS |
103 | if (IS_ERR(priv->mmio)) |
104 | return PTR_ERR(priv->mmio); | |
3e0113a8 | 105 | |
91700361 | 106 | val = readl(priv->mmio + EP93XX_WATCHDOG); |
f52ac8fe | 107 | |
91700361 HS |
108 | wdd = &priv->wdd; |
109 | wdd->bootstatus = (val & 0x01) ? WDIOF_CARDRESET : 0; | |
110 | wdd->info = &ep93xx_wdt_ident; | |
111 | wdd->ops = &ep93xx_wdt_ops; | |
112 | wdd->min_timeout = 1; | |
113 | wdd->max_hw_heartbeat_ms = 200; | |
d6ab0510 | 114 | wdd->parent = dev; |
e12a679d | 115 | |
91700361 | 116 | watchdog_set_nowayout(wdd, nowayout); |
697b41e4 | 117 | |
91700361 | 118 | wdd->timeout = WDT_TIMEOUT; |
d6ab0510 | 119 | watchdog_init_timeout(wdd, timeout, dev); |
697b41e4 | 120 | |
91700361 | 121 | watchdog_set_drvdata(wdd, priv); |
697b41e4 | 122 | |
d6ab0510 | 123 | ret = devm_watchdog_register_device(dev, wdd); |
91700361 HS |
124 | if (ret) |
125 | return ret; | |
e12a679d | 126 | |
d6ab0510 GR |
127 | dev_info(dev, "EP93XX watchdog driver %s\n", |
128 | (val & 0x08) ? " (nCS1 disable detected)" : ""); | |
f52ac8fe | 129 | |
3e0113a8 | 130 | return 0; |
f52ac8fe AZ |
131 | } |
132 | ||
3e0113a8 HS |
133 | static struct platform_driver ep93xx_wdt_driver = { |
134 | .driver = { | |
3e0113a8 HS |
135 | .name = "ep93xx-wdt", |
136 | }, | |
137 | .probe = ep93xx_wdt_probe, | |
3e0113a8 HS |
138 | }; |
139 | ||
140 | module_platform_driver(ep93xx_wdt_driver); | |
f52ac8fe | 141 | |
5f5e1909 JH |
142 | MODULE_AUTHOR("Ray Lehtiniemi <rayl@mail.com>"); |
143 | MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>"); | |
144 | MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>"); | |
f52ac8fe AZ |
145 | MODULE_DESCRIPTION("EP93xx Watchdog"); |
146 | MODULE_LICENSE("GPL"); |