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path: root/drivers/watchdog/jz4740_wdt.c
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Diffstat (limited to 'drivers/watchdog/jz4740_wdt.c')
-rw-r--r--drivers/watchdog/jz4740_wdt.c265
1 files changed, 90 insertions, 175 deletions
diff --git a/drivers/watchdog/jz4740_wdt.c b/drivers/watchdog/jz4740_wdt.c
index 17ef300bccc5..978615ef899d 100644
--- a/drivers/watchdog/jz4740_wdt.c
+++ b/drivers/watchdog/jz4740_wdt.c
@@ -17,18 +17,15 @@
17#include <linux/moduleparam.h> 17#include <linux/moduleparam.h>
18#include <linux/types.h> 18#include <linux/types.h>
19#include <linux/kernel.h> 19#include <linux/kernel.h>
20#include <linux/fs.h>
21#include <linux/miscdevice.h> 20#include <linux/miscdevice.h>
22#include <linux/watchdog.h> 21#include <linux/watchdog.h>
23#include <linux/init.h> 22#include <linux/init.h>
24#include <linux/bitops.h>
25#include <linux/platform_device.h> 23#include <linux/platform_device.h>
26#include <linux/spinlock.h>
27#include <linux/uaccess.h>
28#include <linux/io.h> 24#include <linux/io.h>
29#include <linux/device.h> 25#include <linux/device.h>
30#include <linux/clk.h> 26#include <linux/clk.h>
31#include <linux/slab.h> 27#include <linux/slab.h>
28#include <linux/err.h>
32 29
33#include <asm/mach-jz4740/timer.h> 30#include <asm/mach-jz4740/timer.h>
34 31
@@ -41,9 +38,6 @@
41#define JZ_WDT_CLOCK_RTC 0x2 38#define JZ_WDT_CLOCK_RTC 0x2
42#define JZ_WDT_CLOCK_EXT 0x4 39#define JZ_WDT_CLOCK_EXT 0x4
43 40
44#define WDT_IN_USE 0
45#define WDT_OK_TO_CLOSE 1
46
47#define JZ_WDT_CLOCK_DIV_SHIFT 3 41#define JZ_WDT_CLOCK_DIV_SHIFT 3
48 42
49#define JZ_WDT_CLOCK_DIV_1 (0 << JZ_WDT_CLOCK_DIV_SHIFT) 43#define JZ_WDT_CLOCK_DIV_1 (0 << JZ_WDT_CLOCK_DIV_SHIFT)
@@ -56,32 +50,44 @@
56#define DEFAULT_HEARTBEAT 5 50#define DEFAULT_HEARTBEAT 5
57#define MAX_HEARTBEAT 2048 51#define MAX_HEARTBEAT 2048
58 52
59static struct { 53static bool nowayout = WATCHDOG_NOWAYOUT;
60 void __iomem *base; 54module_param(nowayout, bool, 0);
61 struct resource *mem; 55MODULE_PARM_DESC(nowayout,
62 struct clk *rtc_clk; 56 "Watchdog cannot be stopped once started (default="
63 unsigned long status; 57 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
64} jz4740_wdt;
65 58
66static int heartbeat = DEFAULT_HEARTBEAT; 59static unsigned int heartbeat = DEFAULT_HEARTBEAT;
60module_param(heartbeat, uint, 0);
61MODULE_PARM_DESC(heartbeat,
62 "Watchdog heartbeat period in seconds from 1 to "
63 __MODULE_STRING(MAX_HEARTBEAT) ", default "
64 __MODULE_STRING(DEFAULT_HEARTBEAT));
67 65
66struct jz4740_wdt_drvdata {
67 struct watchdog_device wdt;
68 void __iomem *base;
69 struct clk *rtc_clk;
70};
68 71
69static void jz4740_wdt_service(void) 72static int jz4740_wdt_ping(struct watchdog_device *wdt_dev)
70{ 73{
71 writew(0x0, jz4740_wdt.base + JZ_REG_WDT_TIMER_COUNTER); 74 struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
75
76 writew(0x0, drvdata->base + JZ_REG_WDT_TIMER_COUNTER);
77 return 0;
72} 78}
73 79
74static void jz4740_wdt_set_heartbeat(int new_heartbeat) 80static int jz4740_wdt_set_timeout(struct watchdog_device *wdt_dev,
81 unsigned int new_timeout)
75{ 82{
83 struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
76 unsigned int rtc_clk_rate; 84 unsigned int rtc_clk_rate;
77 unsigned int timeout_value; 85 unsigned int timeout_value;
78 unsigned short clock_div = JZ_WDT_CLOCK_DIV_1; 86 unsigned short clock_div = JZ_WDT_CLOCK_DIV_1;
79 87
80 heartbeat = new_heartbeat; 88 rtc_clk_rate = clk_get_rate(drvdata->rtc_clk);
81
82 rtc_clk_rate = clk_get_rate(jz4740_wdt.rtc_clk);
83 89
84 timeout_value = rtc_clk_rate * heartbeat; 90 timeout_value = rtc_clk_rate * new_timeout;
85 while (timeout_value > 0xffff) { 91 while (timeout_value > 0xffff) {
86 if (clock_div == JZ_WDT_CLOCK_DIV_1024) { 92 if (clock_div == JZ_WDT_CLOCK_DIV_1024) {
87 /* Requested timeout too high; 93 /* Requested timeout too high;
@@ -93,199 +99,115 @@ static void jz4740_wdt_set_heartbeat(int new_heartbeat)
93 clock_div += (1 << JZ_WDT_CLOCK_DIV_SHIFT); 99 clock_div += (1 << JZ_WDT_CLOCK_DIV_SHIFT);
94 } 100 }
95 101
96 writeb(0x0, jz4740_wdt.base + JZ_REG_WDT_COUNTER_ENABLE); 102 writeb(0x0, drvdata->base + JZ_REG_WDT_COUNTER_ENABLE);
97 writew(clock_div, jz4740_wdt.base + JZ_REG_WDT_TIMER_CONTROL); 103 writew(clock_div, drvdata->base + JZ_REG_WDT_TIMER_CONTROL);
98 104
99 writew((u16)timeout_value, jz4740_wdt.base + JZ_REG_WDT_TIMER_DATA); 105 writew((u16)timeout_value, drvdata->base + JZ_REG_WDT_TIMER_DATA);
100 writew(0x0, jz4740_wdt.base + JZ_REG_WDT_TIMER_COUNTER); 106 writew(0x0, drvdata->base + JZ_REG_WDT_TIMER_COUNTER);
101 writew(clock_div | JZ_WDT_CLOCK_RTC, 107 writew(clock_div | JZ_WDT_CLOCK_RTC,
102 jz4740_wdt.base + JZ_REG_WDT_TIMER_CONTROL); 108 drvdata->base + JZ_REG_WDT_TIMER_CONTROL);
103 109
104 writeb(0x1, jz4740_wdt.base + JZ_REG_WDT_COUNTER_ENABLE); 110 writeb(0x1, drvdata->base + JZ_REG_WDT_COUNTER_ENABLE);
105}
106 111
107static void jz4740_wdt_enable(void) 112 wdt_dev->timeout = new_timeout;
108{ 113 return 0;
109 jz4740_timer_enable_watchdog();
110 jz4740_wdt_set_heartbeat(heartbeat);
111}
112
113static void jz4740_wdt_disable(void)
114{
115 jz4740_timer_disable_watchdog();
116 writeb(0x0, jz4740_wdt.base + JZ_REG_WDT_COUNTER_ENABLE);
117} 114}
118 115
119static int jz4740_wdt_open(struct inode *inode, struct file *file) 116static int jz4740_wdt_start(struct watchdog_device *wdt_dev)
120{ 117{
121 if (test_and_set_bit(WDT_IN_USE, &jz4740_wdt.status)) 118 jz4740_timer_enable_watchdog();
122 return -EBUSY; 119 jz4740_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
123
124 jz4740_wdt_enable();
125 120
126 return nonseekable_open(inode, file); 121 return 0;
127} 122}
128 123
129static ssize_t jz4740_wdt_write(struct file *file, const char *data, 124static int jz4740_wdt_stop(struct watchdog_device *wdt_dev)
130 size_t len, loff_t *ppos)
131{ 125{
132 if (len) { 126 struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
133 size_t i;
134
135 clear_bit(WDT_OK_TO_CLOSE, &jz4740_wdt.status);
136 for (i = 0; i != len; i++) {
137 char c;
138 127
139 if (get_user(c, data + i)) 128 jz4740_timer_disable_watchdog();
140 return -EFAULT; 129 writeb(0x0, drvdata->base + JZ_REG_WDT_COUNTER_ENABLE);
141
142 if (c == 'V')
143 set_bit(WDT_OK_TO_CLOSE, &jz4740_wdt.status);
144 }
145 jz4740_wdt_service();
146 }
147 130
148 return len; 131 return 0;
149} 132}
150 133
151static const struct watchdog_info ident = { 134static const struct watchdog_info jz4740_wdt_info = {
152 .options = WDIOF_KEEPALIVEPING, 135 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
153 .identity = "jz4740 Watchdog", 136 .identity = "jz4740 Watchdog",
154}; 137};
155 138
156static long jz4740_wdt_ioctl(struct file *file, 139static const struct watchdog_ops jz4740_wdt_ops = {
157 unsigned int cmd, unsigned long arg)
158{
159 int ret = -ENOTTY;
160 int heartbeat_seconds;
161
162 switch (cmd) {
163 case WDIOC_GETSUPPORT:
164 ret = copy_to_user((struct watchdog_info *)arg, &ident,
165 sizeof(ident)) ? -EFAULT : 0;
166 break;
167
168 case WDIOC_GETSTATUS:
169 case WDIOC_GETBOOTSTATUS:
170 ret = put_user(0, (int *)arg);
171 break;
172
173 case WDIOC_KEEPALIVE:
174 jz4740_wdt_service();
175 return 0;
176
177 case WDIOC_SETTIMEOUT:
178 if (get_user(heartbeat_seconds, (int __user *)arg))
179 return -EFAULT;
180
181 jz4740_wdt_set_heartbeat(heartbeat_seconds);
182 return 0;
183
184 case WDIOC_GETTIMEOUT:
185 return put_user(heartbeat, (int *)arg);
186
187 default:
188 break;
189 }
190
191 return ret;
192}
193
194static int jz4740_wdt_release(struct inode *inode, struct file *file)
195{
196 jz4740_wdt_service();
197
198 if (test_and_clear_bit(WDT_OK_TO_CLOSE, &jz4740_wdt.status))
199 jz4740_wdt_disable();
200
201 clear_bit(WDT_IN_USE, &jz4740_wdt.status);
202 return 0;
203}
204
205static const struct file_operations jz4740_wdt_fops = {
206 .owner = THIS_MODULE, 140 .owner = THIS_MODULE,
207 .llseek = no_llseek, 141 .start = jz4740_wdt_start,
208 .write = jz4740_wdt_write, 142 .stop = jz4740_wdt_stop,
209 .unlocked_ioctl = jz4740_wdt_ioctl, 143 .ping = jz4740_wdt_ping,
210 .open = jz4740_wdt_open, 144 .set_timeout = jz4740_wdt_set_timeout,
211 .release = jz4740_wdt_release,
212};
213
214static struct miscdevice jz4740_wdt_miscdev = {
215 .minor = WATCHDOG_MINOR,
216 .name = "watchdog",
217 .fops = &jz4740_wdt_fops,
218}; 145};
219 146
220static int __devinit jz4740_wdt_probe(struct platform_device *pdev) 147static int __devinit jz4740_wdt_probe(struct platform_device *pdev)
221{ 148{
222 int ret = 0, size; 149 struct jz4740_wdt_drvdata *drvdata;
223 struct resource *res; 150 struct watchdog_device *jz4740_wdt;
224 struct device *dev = &pdev->dev; 151 struct resource *res;
225 152 int ret;
226 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 153
227 if (res == NULL) { 154 drvdata = devm_kzalloc(&pdev->dev, sizeof(struct jz4740_wdt_drvdata),
228 dev_err(dev, "failed to get memory region resource\n"); 155 GFP_KERNEL);
229 return -ENXIO; 156 if (!drvdata) {
157 dev_err(&pdev->dev, "Unable to alloacate watchdog device\n");
158 return -ENOMEM;
230 } 159 }
231 160
232 size = resource_size(res); 161 if (heartbeat < 1 || heartbeat > MAX_HEARTBEAT)
233 jz4740_wdt.mem = request_mem_region(res->start, size, pdev->name); 162 heartbeat = DEFAULT_HEARTBEAT;
234 if (jz4740_wdt.mem == NULL) {
235 dev_err(dev, "failed to get memory region\n");
236 return -EBUSY;
237 }
238 163
239 jz4740_wdt.base = ioremap_nocache(res->start, size); 164 jz4740_wdt = &drvdata->wdt;
240 if (jz4740_wdt.base == NULL) { 165 jz4740_wdt->info = &jz4740_wdt_info;
241 dev_err(dev, "failed to map memory region\n"); 166 jz4740_wdt->ops = &jz4740_wdt_ops;
167 jz4740_wdt->timeout = heartbeat;
168 jz4740_wdt->min_timeout = 1;
169 jz4740_wdt->max_timeout = MAX_HEARTBEAT;
170 watchdog_set_nowayout(jz4740_wdt, nowayout);
171 watchdog_set_drvdata(jz4740_wdt, drvdata);
172
173 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
174 drvdata->base = devm_request_and_ioremap(&pdev->dev, res);
175 if (drvdata->base == NULL) {
242 ret = -EBUSY; 176 ret = -EBUSY;
243 goto err_release_region; 177 goto err_out;
244 } 178 }
245 179
246 jz4740_wdt.rtc_clk = clk_get(NULL, "rtc"); 180 drvdata->rtc_clk = clk_get(NULL, "rtc");
247 if (IS_ERR(jz4740_wdt.rtc_clk)) { 181 if (IS_ERR(drvdata->rtc_clk)) {
248 dev_err(dev, "cannot find RTC clock\n"); 182 dev_err(&pdev->dev, "cannot find RTC clock\n");
249 ret = PTR_ERR(jz4740_wdt.rtc_clk); 183 ret = PTR_ERR(drvdata->rtc_clk);
250 goto err_iounmap; 184 goto err_out;
251 } 185 }
252 186
253 ret = misc_register(&jz4740_wdt_miscdev); 187 ret = watchdog_register_device(&drvdata->wdt);
254 if (ret < 0) { 188 if (ret < 0)
255 dev_err(dev, "cannot register misc device\n");
256 goto err_disable_clk; 189 goto err_disable_clk;
257 }
258 190
191 platform_set_drvdata(pdev, drvdata);
259 return 0; 192 return 0;
260 193
261err_disable_clk: 194err_disable_clk:
262 clk_put(jz4740_wdt.rtc_clk); 195 clk_put(drvdata->rtc_clk);
263err_iounmap: 196err_out:
264 iounmap(jz4740_wdt.base);
265err_release_region:
266 release_mem_region(jz4740_wdt.mem->start,
267 resource_size(jz4740_wdt.mem));
268 return ret; 197 return ret;
269} 198}
270 199
271
272static int __devexit jz4740_wdt_remove(struct platform_device *pdev) 200static int __devexit jz4740_wdt_remove(struct platform_device *pdev)
273{ 201{
274 jz4740_wdt_disable(); 202 struct jz4740_wdt_drvdata *drvdata = platform_get_drvdata(pdev);
275 misc_deregister(&jz4740_wdt_miscdev);
276 clk_put(jz4740_wdt.rtc_clk);
277 203
278 iounmap(jz4740_wdt.base); 204 jz4740_wdt_stop(&drvdata->wdt);
279 jz4740_wdt.base = NULL; 205 watchdog_unregister_device(&drvdata->wdt);
280 206 clk_put(drvdata->rtc_clk);
281 release_mem_region(jz4740_wdt.mem->start,
282 resource_size(jz4740_wdt.mem));
283 jz4740_wdt.mem = NULL;
284 207
285 return 0; 208 return 0;
286} 209}
287 210
288
289static struct platform_driver jz4740_wdt_driver = { 211static struct platform_driver jz4740_wdt_driver = {
290 .probe = jz4740_wdt_probe, 212 .probe = jz4740_wdt_probe,
291 .remove = __devexit_p(jz4740_wdt_remove), 213 .remove = __devexit_p(jz4740_wdt_remove),
@@ -299,13 +221,6 @@ module_platform_driver(jz4740_wdt_driver);
299 221
300MODULE_AUTHOR("Paul Cercueil <paul@crapouillou.net>"); 222MODULE_AUTHOR("Paul Cercueil <paul@crapouillou.net>");
301MODULE_DESCRIPTION("jz4740 Watchdog Driver"); 223MODULE_DESCRIPTION("jz4740 Watchdog Driver");
302
303module_param(heartbeat, int, 0);
304MODULE_PARM_DESC(heartbeat,
305 "Watchdog heartbeat period in seconds from 1 to "
306 __MODULE_STRING(MAX_HEARTBEAT) ", default "
307 __MODULE_STRING(DEFAULT_HEARTBEAT));
308
309MODULE_LICENSE("GPL"); 224MODULE_LICENSE("GPL");
310MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); 225MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
311MODULE_ALIAS("platform:jz4740-wdt"); 226MODULE_ALIAS("platform:jz4740-wdt");