net: dsa: b53: Fix ARL register definitions
[linux/fpc-iii.git] / drivers / watchdog / rtd119x_wdt.c
blob99caec6882d2f1cef3131df8e3b38dfa8d6c006b
1 /*
2 * Realtek RTD129x watchdog
4 * Copyright (c) 2017 Andreas Färber
6 * SPDX-License-Identifier: GPL-2.0+
7 */
9 #include <linux/bitops.h>
10 #include <linux/clk.h>
11 #include <linux/io.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_address.h>
15 #include <linux/platform_device.h>
16 #include <linux/watchdog.h>
18 #define RTD119X_TCWCR 0x0
19 #define RTD119X_TCWTR 0x4
20 #define RTD119X_TCWOV 0xc
22 #define RTD119X_TCWCR_WDEN_DISABLED 0xa5
23 #define RTD119X_TCWCR_WDEN_ENABLED 0xff
24 #define RTD119X_TCWCR_WDEN_MASK 0xff
26 #define RTD119X_TCWTR_WDCLR BIT(0)
28 struct rtd119x_watchdog_device {
29 struct watchdog_device wdt_dev;
30 void __iomem *base;
31 struct clk *clk;
34 static int rtd119x_wdt_start(struct watchdog_device *wdev)
36 struct rtd119x_watchdog_device *data = watchdog_get_drvdata(wdev);
37 u32 val;
39 val = readl_relaxed(data->base + RTD119X_TCWCR);
40 val &= ~RTD119X_TCWCR_WDEN_MASK;
41 val |= RTD119X_TCWCR_WDEN_ENABLED;
42 writel(val, data->base + RTD119X_TCWCR);
44 return 0;
47 static int rtd119x_wdt_stop(struct watchdog_device *wdev)
49 struct rtd119x_watchdog_device *data = watchdog_get_drvdata(wdev);
50 u32 val;
52 val = readl_relaxed(data->base + RTD119X_TCWCR);
53 val &= ~RTD119X_TCWCR_WDEN_MASK;
54 val |= RTD119X_TCWCR_WDEN_DISABLED;
55 writel(val, data->base + RTD119X_TCWCR);
57 return 0;
60 static int rtd119x_wdt_ping(struct watchdog_device *wdev)
62 struct rtd119x_watchdog_device *data = watchdog_get_drvdata(wdev);
64 writel_relaxed(RTD119X_TCWTR_WDCLR, data->base + RTD119X_TCWTR);
66 return rtd119x_wdt_start(wdev);
69 static int rtd119x_wdt_set_timeout(struct watchdog_device *wdev, unsigned int val)
71 struct rtd119x_watchdog_device *data = watchdog_get_drvdata(wdev);
73 writel(val * clk_get_rate(data->clk), data->base + RTD119X_TCWOV);
75 data->wdt_dev.timeout = val;
77 return 0;
80 static const struct watchdog_ops rtd119x_wdt_ops = {
81 .owner = THIS_MODULE,
82 .start = rtd119x_wdt_start,
83 .stop = rtd119x_wdt_stop,
84 .ping = rtd119x_wdt_ping,
85 .set_timeout = rtd119x_wdt_set_timeout,
88 static const struct watchdog_info rtd119x_wdt_info = {
89 .identity = "rtd119x-wdt",
90 .options = 0,
93 static const struct of_device_id rtd119x_wdt_dt_ids[] = {
94 { .compatible = "realtek,rtd1295-watchdog" },
95 { }
98 static int rtd119x_wdt_probe(struct platform_device *pdev)
100 struct rtd119x_watchdog_device *data;
101 struct resource *res;
102 int ret;
104 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
105 if (!data)
106 return -ENOMEM;
108 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
109 data->base = devm_ioremap_resource(&pdev->dev, res);
110 if (IS_ERR(data->base))
111 return PTR_ERR(data->base);
113 data->clk = of_clk_get(pdev->dev.of_node, 0);
114 if (IS_ERR(data->clk))
115 return PTR_ERR(data->clk);
117 ret = clk_prepare_enable(data->clk);
118 if (ret) {
119 clk_put(data->clk);
120 return ret;
123 data->wdt_dev.info = &rtd119x_wdt_info;
124 data->wdt_dev.ops = &rtd119x_wdt_ops;
125 data->wdt_dev.timeout = 120;
126 data->wdt_dev.max_timeout = 0xffffffff / clk_get_rate(data->clk);
127 data->wdt_dev.min_timeout = 1;
128 data->wdt_dev.parent = &pdev->dev;
130 watchdog_stop_on_reboot(&data->wdt_dev);
131 watchdog_set_drvdata(&data->wdt_dev, data);
132 platform_set_drvdata(pdev, data);
134 writel_relaxed(RTD119X_TCWTR_WDCLR, data->base + RTD119X_TCWTR);
135 rtd119x_wdt_set_timeout(&data->wdt_dev, data->wdt_dev.timeout);
136 rtd119x_wdt_stop(&data->wdt_dev);
138 ret = watchdog_register_device(&data->wdt_dev);
139 if (ret) {
140 clk_disable_unprepare(data->clk);
141 clk_put(data->clk);
142 return ret;
145 return 0;
148 static int rtd119x_wdt_remove(struct platform_device *pdev)
150 struct rtd119x_watchdog_device *data = platform_get_drvdata(pdev);
152 watchdog_unregister_device(&data->wdt_dev);
154 clk_disable_unprepare(data->clk);
155 clk_put(data->clk);
157 return 0;
160 static struct platform_driver rtd119x_wdt_driver = {
161 .probe = rtd119x_wdt_probe,
162 .remove = rtd119x_wdt_remove,
163 .driver = {
164 .name = "rtd1295-watchdog",
165 .of_match_table = rtd119x_wdt_dt_ids,
168 builtin_platform_driver(rtd119x_wdt_driver);