Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * Watchdog driver for Atmel AT91RM9200 (Thunder)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  *  Copyright (C) 2003 SAN People (Pty) Ltd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include <linux/bitops.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/delay.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <linux/errno.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) #include <linux/fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) #include <linux/io.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) #include <linux/mfd/syscon.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) #include <linux/mfd/syscon/atmel-st.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) #include <linux/miscdevice.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) #include <linux/moduleparam.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) #include <linux/reboot.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) #include <linux/regmap.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) #include <linux/watchdog.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) #include <linux/uaccess.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) #include <linux/of.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) #include <linux/of_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) #define WDT_DEFAULT_TIME	5	/* seconds */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) #define WDT_MAX_TIME		256	/* seconds */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) static int wdt_time = WDT_DEFAULT_TIME;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) static bool nowayout = WATCHDOG_NOWAYOUT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) static struct regmap *regmap_st;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) module_param(wdt_time, int, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) MODULE_PARM_DESC(wdt_time, "Watchdog time in seconds. (default="
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 				__MODULE_STRING(WDT_DEFAULT_TIME) ")");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) #ifdef CONFIG_WATCHDOG_NOWAYOUT
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) module_param(nowayout, bool, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) MODULE_PARM_DESC(nowayout,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 		"Watchdog cannot be stopped once started (default="
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) static unsigned long at91wdt_busy;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) /* ......................................................................... */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) static int at91rm9200_restart(struct notifier_block *this,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 					unsigned long mode, void *cmd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	 * Perform a hardware reset with the use of the Watchdog timer.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 	regmap_write(regmap_st, AT91_ST_WDMR,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 		     AT91_ST_RSTEN | AT91_ST_EXTEN | 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 	regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 	mdelay(2000);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 	pr_emerg("Unable to restart system\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 	return NOTIFY_DONE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) static struct notifier_block at91rm9200_restart_nb = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 	.notifier_call = at91rm9200_restart,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 	.priority = 192,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77)  * Disable the watchdog.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) static inline void at91_wdt_stop(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 	regmap_write(regmap_st, AT91_ST_WDMR, AT91_ST_EXTEN);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85)  * Enable and reset the watchdog.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) static inline void at91_wdt_start(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 	regmap_write(regmap_st, AT91_ST_WDMR, AT91_ST_EXTEN | AT91_ST_RSTEN |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 				(((65536 * wdt_time) >> 8) & AT91_ST_WDV));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 	regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95)  * Reload the watchdog timer.  (ie, pat the watchdog)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) static inline void at91_wdt_reload(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) /* ......................................................................... */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105)  * Watchdog device is opened, and watchdog starts running.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) static int at91_wdt_open(struct inode *inode, struct file *file)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 	if (test_and_set_bit(0, &at91wdt_busy))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 		return -EBUSY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 	at91_wdt_start();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 	return stream_open(inode, file);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117)  * Close the watchdog device.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118)  * If CONFIG_WATCHDOG_NOWAYOUT is NOT defined then the watchdog is also
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119)  *  disabled.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) static int at91_wdt_close(struct inode *inode, struct file *file)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 	/* Disable the watchdog when file is closed */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 	if (!nowayout)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 		at91_wdt_stop();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 	clear_bit(0, &at91wdt_busy);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132)  * Change the watchdog time interval.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) static int at91_wdt_settimeout(int new_time)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 	 * All counting occurs at SLOW_CLOCK / 128 = 256 Hz
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 	 *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 	 * Since WDV is a 16-bit counter, the maximum period is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 	 * 65536 / 256 = 256 seconds.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 	if ((new_time <= 0) || (new_time > WDT_MAX_TIME))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 	/* Set new watchdog time. It will be used when
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 	   at91_wdt_start() is called. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 	wdt_time = new_time;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) static const struct watchdog_info at91_wdt_info = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	.identity	= "at91 watchdog",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 	.options	= WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157)  * Handle commands from user-space.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) static long at91_wdt_ioctl(struct file *file,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 					unsigned int cmd, unsigned long arg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 	void __user *argp = (void __user *)arg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 	int __user *p = argp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 	int new_value;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 	switch (cmd) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 	case WDIOC_GETSUPPORT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 		return copy_to_user(argp, &at91_wdt_info,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 				sizeof(at91_wdt_info)) ? -EFAULT : 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 	case WDIOC_GETSTATUS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 	case WDIOC_GETBOOTSTATUS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 		return put_user(0, p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 	case WDIOC_SETOPTIONS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 		if (get_user(new_value, p))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 			return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 		if (new_value & WDIOS_DISABLECARD)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 			at91_wdt_stop();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 		if (new_value & WDIOS_ENABLECARD)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 			at91_wdt_start();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 	case WDIOC_KEEPALIVE:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 		at91_wdt_reload();	/* pat the watchdog */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 	case WDIOC_SETTIMEOUT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 		if (get_user(new_value, p))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 			return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 		if (at91_wdt_settimeout(new_value))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 			return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 		/* Enable new time value */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 		at91_wdt_start();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 		/* Return current value */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 		return put_user(wdt_time, p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 	case WDIOC_GETTIMEOUT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 		return put_user(wdt_time, p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) 	default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 		return -ENOTTY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201)  * Pat the watchdog whenever device is written to.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) static ssize_t at91_wdt_write(struct file *file, const char *data,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) 						size_t len, loff_t *ppos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) 	at91_wdt_reload();		/* pat the watchdog */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) 	return len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) /* ......................................................................... */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) static const struct file_operations at91wdt_fops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) 	.owner		= THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) 	.llseek		= no_llseek,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) 	.unlocked_ioctl	= at91_wdt_ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) 	.compat_ioctl	= compat_ptr_ioctl,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) 	.open		= at91_wdt_open,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) 	.release	= at91_wdt_close,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) 	.write		= at91_wdt_write,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) static struct miscdevice at91wdt_miscdev = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) 	.minor		= WATCHDOG_MINOR,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) 	.name		= "watchdog",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) 	.fops		= &at91wdt_fops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) static int at91wdt_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) 	struct device *dev = &pdev->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) 	struct device *parent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) 	int res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) 	if (at91wdt_miscdev.parent)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) 		return -EBUSY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) 	at91wdt_miscdev.parent = &pdev->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) 	parent = dev->parent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) 	if (!parent) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) 		dev_err(dev, "no parent\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) 		return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) 	regmap_st = syscon_node_to_regmap(parent->of_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) 	if (IS_ERR(regmap_st))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) 		return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) 	res = misc_register(&at91wdt_miscdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) 	if (res)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) 		return res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) 	res = register_restart_handler(&at91rm9200_restart_nb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) 	if (res)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) 		dev_warn(dev, "failed to register restart handler\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) 	pr_info("AT91 Watchdog Timer enabled (%d seconds%s)\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) 		wdt_time, nowayout ? ", nowayout" : "");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) static int at91wdt_remove(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) 	struct device *dev = &pdev->dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) 	int res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) 	res = unregister_restart_handler(&at91rm9200_restart_nb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) 	if (res)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) 		dev_warn(dev, "failed to unregister restart handler\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) 	misc_deregister(&at91wdt_miscdev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) 	at91wdt_miscdev.parent = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) 	return res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) static void at91wdt_shutdown(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) 	at91_wdt_stop();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) #ifdef CONFIG_PM
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) static int at91wdt_suspend(struct platform_device *pdev, pm_message_t message)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) 	at91_wdt_stop();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) static int at91wdt_resume(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) 	if (at91wdt_busy)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) 		at91_wdt_start();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) #define at91wdt_suspend NULL
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) #define at91wdt_resume	NULL
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) static const struct of_device_id at91_wdt_dt_ids[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) 	{ .compatible = "atmel,at91rm9200-wdt" },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) 	{ /* sentinel */ }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) MODULE_DEVICE_TABLE(of, at91_wdt_dt_ids);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) static struct platform_driver at91wdt_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) 	.probe		= at91wdt_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) 	.remove		= at91wdt_remove,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) 	.shutdown	= at91wdt_shutdown,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) 	.suspend	= at91wdt_suspend,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) 	.resume		= at91wdt_resume,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) 	.driver		= {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) 		.name	= "atmel_st_watchdog",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) 		.of_match_table = at91_wdt_dt_ids,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) 	},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) static int __init at91_wdt_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) 	/* Check that the heartbeat value is within range;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) 	   if not reset to the default */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) 	if (at91_wdt_settimeout(wdt_time)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) 		at91_wdt_settimeout(WDT_DEFAULT_TIME);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) 		pr_info("wdt_time value must be 1 <= wdt_time <= 256, using %d\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) 			wdt_time);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) 	return platform_driver_register(&at91wdt_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) static void __exit at91_wdt_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) 	platform_driver_unregister(&at91wdt_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) module_init(at91_wdt_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) module_exit(at91_wdt_exit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) MODULE_AUTHOR("Andrew Victor");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) MODULE_DESCRIPTION("Watchdog driver for Atmel AT91RM9200");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) MODULE_ALIAS("platform:atmel_st_watchdog");