drivers/watchdog/sa1100_wdt.c

1 // SPDX-License-Identifier: GPL-2.0+
3  *	Watchdog driver for the SA11x0/PXA2xx
10  *	"AS-IS" and at no charge.
27 #include <linux/watchdog.h>
34 #define REG_OSMR0  	0x0000  /* OS timer Match Reg. 0 */
35 #define REG_OSMR1  	0x0004  /* OS timer Match Reg. 1 */
36 #define REG_OSMR2  	0x0008  /* OS timer Match Reg. 2 */
37 #define REG_OSMR3  	0x000c  /* OS timer Match Reg. 3 */
38 #define REG_OSCR   	0x0010  /* OS timer Counter Reg. */
39 #define REG_OSSR   	0x0014  /* OS timer Status Reg. */
40 #define REG_OWER   	0x0018  /* OS timer Watch-dog Enable Reg. */
41 #define REG_OIER  	0x001C  /* OS timer Interrupt Enable Reg. */
48 #define OWER_WME	(1 << 0)	/* Watchdog Match Enable */
77 		return -EBUSY;  in sa1100dog_open()
79 	/* Activate SA1100 Watchdog timer */  in sa1100dog_open()
88  * The watchdog cannot be disabled.
91  * clearing REG_OIER[E3] would prevent the watchdog timing out but this
96 	pr_crit("Device closed - timer will not stop\n");  in sa1100dog_release()
105 		/* Refresh OSMR3 timer. */  in sa1100dog_write()
113 	.identity	= "SA1100/PXA255 Watchdog",
120 	int ret = -ENOTTY;  in sa1100dog_ioctl()
128 				   sizeof(ident)) ? -EFAULT : 0;  in sa1100dog_ioctl()
150 			ret = -EINVAL;  in sa1100dog_ioctl()
176 	.name		= "watchdog",
191 		return -ENXIO;  in sa1100dog_probe()
192 	reg_base = devm_ioremap(&pdev->dev, res->start, resource_size(res));  in sa1100dog_probe()
194 		return -ENOMEM;  in sa1100dog_probe()
198 		pr_err("SA1100/PXA2xx Watchdog Timer: clock not found: %d\n",  in sa1100dog_probe()
205 		pr_err("SA1100/PXA2xx Watchdog Timer: clock failed to prepare+enable: %d\n",  in sa1100dog_probe()
212 	platform_data = pdev->dev.platform_data;  in sa1100dog_probe()
219 		pr_info("SA1100/PXA2xx Watchdog Timer: timer margin %d sec\n",  in sa1100dog_probe()
245 MODULE_DESCRIPTION("SA1100/PXA2xx Watchdog");
248 MODULE_PARM_DESC(margin, "Watchdog margin in seconds (default 60s)");