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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* linux/drivers/char/watchdog/s3c2410_wdt.c
2 *
3 * Copyright (c) 2004 Simtec Electronics
4 * Ben Dooks <ben@simtec.co.uk>
5 *
6 * S3C2410 Watchdog Timer Support
7 *
8 * Based on, softdog.c by Alan Cox,
Alan Cox29fa0582008-10-27 15:17:56 +00009 * (c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Linus Torvalds1da177e2005-04-16 15:20:36 -070024*/
25
Joe Perches27c766a2012-02-15 15:06:19 -080026#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
27
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include <linux/module.h>
29#include <linux/moduleparam.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#include <linux/types.h>
31#include <linux/timer.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070032#include <linux/watchdog.h>
Russell Kingd052d1b2005-10-29 19:07:23 +010033#include <linux/platform_device.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <linux/interrupt.h>
Russell Kingf8ce2542006-01-07 16:15:52 +000035#include <linux/clk.h>
Alan Cox41dc8b72008-08-04 17:54:46 +010036#include <linux/uaccess.h>
37#include <linux/io.h>
Ben Dookse02f8382009-10-30 00:30:25 +000038#include <linux/cpufreq.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090039#include <linux/slab.h>
Wolfram Sang25dc46e2011-09-26 15:40:14 +020040#include <linux/err.h>
Wim Van Sebroeck3016a552012-05-03 05:24:17 +000041#include <linux/of.h>
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +053042#include <linux/mfd/syscon.h>
43#include <linux/regmap.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070044
Tomasz Figaa8f54012013-06-17 23:45:24 +090045#define S3C2410_WTCON 0x00
46#define S3C2410_WTDAT 0x04
47#define S3C2410_WTCNT 0x08
Linus Torvalds1da177e2005-04-16 15:20:36 -070048
Tomasz Figaa8f54012013-06-17 23:45:24 +090049#define S3C2410_WTCON_RSTEN (1 << 0)
50#define S3C2410_WTCON_INTEN (1 << 2)
51#define S3C2410_WTCON_ENABLE (1 << 5)
Linus Torvalds1da177e2005-04-16 15:20:36 -070052
Tomasz Figaa8f54012013-06-17 23:45:24 +090053#define S3C2410_WTCON_DIV16 (0 << 3)
54#define S3C2410_WTCON_DIV32 (1 << 3)
55#define S3C2410_WTCON_DIV64 (2 << 3)
56#define S3C2410_WTCON_DIV128 (3 << 3)
57
58#define S3C2410_WTCON_PRESCALE(x) ((x) << 8)
59#define S3C2410_WTCON_PRESCALE_MASK (0xff << 8)
Linus Torvalds1da177e2005-04-16 15:20:36 -070060
Linus Torvalds1da177e2005-04-16 15:20:36 -070061#define CONFIG_S3C2410_WATCHDOG_ATBOOT (0)
62#define CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME (15)
63
Doug Andersoncffc9a62013-12-06 13:08:07 -080064#define EXYNOS5_RST_STAT_REG_OFFSET 0x0404
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +053065#define EXYNOS5_WDT_DISABLE_REG_OFFSET 0x0408
66#define EXYNOS5_WDT_MASK_RESET_REG_OFFSET 0x040c
67#define QUIRK_HAS_PMU_CONFIG (1 << 0)
Doug Andersoncffc9a62013-12-06 13:08:07 -080068#define QUIRK_HAS_RST_STAT (1 << 1)
69
70/* These quirks require that we have a PMU register map */
71#define QUIRKS_HAVE_PMUREG (QUIRK_HAS_PMU_CONFIG | \
72 QUIRK_HAS_RST_STAT)
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +053073
Wim Van Sebroeck86a1e182012-03-05 16:51:11 +010074static bool nowayout = WATCHDOG_NOWAYOUT;
Fabio Porceddac1fd5f62013-02-14 09:14:25 +010075static int tmr_margin;
Linus Torvalds1da177e2005-04-16 15:20:36 -070076static int tmr_atboot = CONFIG_S3C2410_WATCHDOG_ATBOOT;
Alan Cox41dc8b72008-08-04 17:54:46 +010077static int soft_noboot;
78static int debug;
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
80module_param(tmr_margin, int, 0);
81module_param(tmr_atboot, int, 0);
Wim Van Sebroeck86a1e182012-03-05 16:51:11 +010082module_param(nowayout, bool, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070083module_param(soft_noboot, int, 0);
84module_param(debug, int, 0);
85
Randy Dunlap76550d32010-05-01 09:46:15 -070086MODULE_PARM_DESC(tmr_margin, "Watchdog tmr_margin in seconds. (default="
Alan Cox41dc8b72008-08-04 17:54:46 +010087 __MODULE_STRING(CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME) ")");
88MODULE_PARM_DESC(tmr_atboot,
89 "Watchdog is started at boot time if set to 1, default="
90 __MODULE_STRING(CONFIG_S3C2410_WATCHDOG_ATBOOT));
91MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
92 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
Wim Van Sebroecka77dba72009-04-14 20:20:07 +000093MODULE_PARM_DESC(soft_noboot, "Watchdog action, set to 1 to ignore reboots, "
Randy Dunlap76550d32010-05-01 09:46:15 -070094 "0 to reboot (default 0)");
95MODULE_PARM_DESC(debug, "Watchdog debug, set to >1 for debug (default 0)");
Linus Torvalds1da177e2005-04-16 15:20:36 -070096
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +053097/**
98 * struct s3c2410_wdt_variant - Per-variant config data
99 *
100 * @disable_reg: Offset in pmureg for the register that disables the watchdog
101 * timer reset functionality.
102 * @mask_reset_reg: Offset in pmureg for the register that masks the watchdog
103 * timer reset functionality.
104 * @mask_bit: Bit number for the watchdog timer in the disable register and the
105 * mask reset register.
Doug Andersoncffc9a62013-12-06 13:08:07 -0800106 * @rst_stat_reg: Offset in pmureg for the register that has the reset status.
107 * @rst_stat_bit: Bit number in the rst_stat register indicating a watchdog
108 * reset.
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530109 * @quirks: A bitfield of quirks.
110 */
111
112struct s3c2410_wdt_variant {
113 int disable_reg;
114 int mask_reset_reg;
115 int mask_bit;
Doug Andersoncffc9a62013-12-06 13:08:07 -0800116 int rst_stat_reg;
117 int rst_stat_bit;
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530118 u32 quirks;
119};
120
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530121struct s3c2410_wdt {
122 struct device *dev;
123 struct clk *clock;
124 void __iomem *reg_base;
125 unsigned int count;
126 spinlock_t lock;
127 unsigned long wtcon_save;
128 unsigned long wtdat_save;
129 struct watchdog_device wdt_device;
130 struct notifier_block freq_transition;
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530131 struct s3c2410_wdt_variant *drv_data;
132 struct regmap *pmureg;
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530133};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530135static const struct s3c2410_wdt_variant drv_data_s3c2410 = {
136 .quirks = 0
137};
138
139#ifdef CONFIG_OF
140static const struct s3c2410_wdt_variant drv_data_exynos5250 = {
141 .disable_reg = EXYNOS5_WDT_DISABLE_REG_OFFSET,
142 .mask_reset_reg = EXYNOS5_WDT_MASK_RESET_REG_OFFSET,
143 .mask_bit = 20,
Doug Andersoncffc9a62013-12-06 13:08:07 -0800144 .rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
145 .rst_stat_bit = 20,
146 .quirks = QUIRK_HAS_PMU_CONFIG | QUIRK_HAS_RST_STAT,
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530147};
148
149static const struct s3c2410_wdt_variant drv_data_exynos5420 = {
150 .disable_reg = EXYNOS5_WDT_DISABLE_REG_OFFSET,
151 .mask_reset_reg = EXYNOS5_WDT_MASK_RESET_REG_OFFSET,
152 .mask_bit = 0,
Doug Andersoncffc9a62013-12-06 13:08:07 -0800153 .rst_stat_reg = EXYNOS5_RST_STAT_REG_OFFSET,
154 .rst_stat_bit = 9,
155 .quirks = QUIRK_HAS_PMU_CONFIG | QUIRK_HAS_RST_STAT,
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530156};
157
158static const struct of_device_id s3c2410_wdt_match[] = {
159 { .compatible = "samsung,s3c2410-wdt",
160 .data = &drv_data_s3c2410 },
161 { .compatible = "samsung,exynos5250-wdt",
162 .data = &drv_data_exynos5250 },
163 { .compatible = "samsung,exynos5420-wdt",
164 .data = &drv_data_exynos5420 },
165 {},
166};
167MODULE_DEVICE_TABLE(of, s3c2410_wdt_match);
168#endif
169
170static const struct platform_device_id s3c2410_wdt_ids[] = {
171 {
172 .name = "s3c2410-wdt",
173 .driver_data = (unsigned long)&drv_data_s3c2410,
174 },
175 {}
176};
177MODULE_DEVICE_TABLE(platform, s3c2410_wdt_ids);
178
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179/* watchdog control routines */
180
Joe Perches27c766a2012-02-15 15:06:19 -0800181#define DBG(fmt, ...) \
182do { \
183 if (debug) \
184 pr_info(fmt, ##__VA_ARGS__); \
185} while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186
187/* functions */
188
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530189static inline struct s3c2410_wdt *freq_to_wdt(struct notifier_block *nb)
190{
191 return container_of(nb, struct s3c2410_wdt, freq_transition);
192}
193
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530194static int s3c2410wdt_mask_and_disable_reset(struct s3c2410_wdt *wdt, bool mask)
195{
196 int ret;
197 u32 mask_val = 1 << wdt->drv_data->mask_bit;
198 u32 val = 0;
199
200 /* No need to do anything if no PMU CONFIG needed */
201 if (!(wdt->drv_data->quirks & QUIRK_HAS_PMU_CONFIG))
202 return 0;
203
204 if (mask)
205 val = mask_val;
206
207 ret = regmap_update_bits(wdt->pmureg,
208 wdt->drv_data->disable_reg,
209 mask_val, val);
210 if (ret < 0)
211 goto error;
212
213 ret = regmap_update_bits(wdt->pmureg,
214 wdt->drv_data->mask_reset_reg,
215 mask_val, val);
216 error:
217 if (ret < 0)
218 dev_err(wdt->dev, "failed to update reg(%d)\n", ret);
219
220 return ret;
221}
222
Wolfram Sang25dc46e2011-09-26 15:40:14 +0200223static int s3c2410wdt_keepalive(struct watchdog_device *wdd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224{
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530225 struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
226
227 spin_lock(&wdt->lock);
228 writel(wdt->count, wdt->reg_base + S3C2410_WTCNT);
229 spin_unlock(&wdt->lock);
Wolfram Sang25dc46e2011-09-26 15:40:14 +0200230
231 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232}
233
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530234static void __s3c2410wdt_stop(struct s3c2410_wdt *wdt)
Alan Cox41dc8b72008-08-04 17:54:46 +0100235{
236 unsigned long wtcon;
237
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530238 wtcon = readl(wdt->reg_base + S3C2410_WTCON);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 wtcon &= ~(S3C2410_WTCON_ENABLE | S3C2410_WTCON_RSTEN);
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530240 writel(wtcon, wdt->reg_base + S3C2410_WTCON);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241}
242
Wolfram Sang25dc46e2011-09-26 15:40:14 +0200243static int s3c2410wdt_stop(struct watchdog_device *wdd)
Alan Cox41dc8b72008-08-04 17:54:46 +0100244{
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530245 struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
246
247 spin_lock(&wdt->lock);
248 __s3c2410wdt_stop(wdt);
249 spin_unlock(&wdt->lock);
Wolfram Sang25dc46e2011-09-26 15:40:14 +0200250
251 return 0;
Alan Cox41dc8b72008-08-04 17:54:46 +0100252}
253
Wolfram Sang25dc46e2011-09-26 15:40:14 +0200254static int s3c2410wdt_start(struct watchdog_device *wdd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255{
256 unsigned long wtcon;
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530257 struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530259 spin_lock(&wdt->lock);
Alan Cox41dc8b72008-08-04 17:54:46 +0100260
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530261 __s3c2410wdt_stop(wdt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530263 wtcon = readl(wdt->reg_base + S3C2410_WTCON);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264 wtcon |= S3C2410_WTCON_ENABLE | S3C2410_WTCON_DIV128;
265
266 if (soft_noboot) {
267 wtcon |= S3C2410_WTCON_INTEN;
268 wtcon &= ~S3C2410_WTCON_RSTEN;
269 } else {
270 wtcon &= ~S3C2410_WTCON_INTEN;
271 wtcon |= S3C2410_WTCON_RSTEN;
272 }
273
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530274 DBG("%s: count=0x%08x, wtcon=%08lx\n",
275 __func__, wdt->count, wtcon);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530277 writel(wdt->count, wdt->reg_base + S3C2410_WTDAT);
278 writel(wdt->count, wdt->reg_base + S3C2410_WTCNT);
279 writel(wtcon, wdt->reg_base + S3C2410_WTCON);
280 spin_unlock(&wdt->lock);
Wolfram Sang25dc46e2011-09-26 15:40:14 +0200281
282 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283}
284
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530285static inline int s3c2410wdt_is_running(struct s3c2410_wdt *wdt)
Ben Dookse02f8382009-10-30 00:30:25 +0000286{
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530287 return readl(wdt->reg_base + S3C2410_WTCON) & S3C2410_WTCON_ENABLE;
Ben Dookse02f8382009-10-30 00:30:25 +0000288}
289
Wolfram Sang25dc46e2011-09-26 15:40:14 +0200290static int s3c2410wdt_set_heartbeat(struct watchdog_device *wdd, unsigned timeout)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291{
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530292 struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
293 unsigned long freq = clk_get_rate(wdt->clock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 unsigned int count;
295 unsigned int divisor = 1;
296 unsigned long wtcon;
297
298 if (timeout < 1)
299 return -EINVAL;
300
Doug Anderson17862442013-11-26 16:57:19 -0800301 freq = DIV_ROUND_UP(freq, 128);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 count = timeout * freq;
303
Ben Dookse02f8382009-10-30 00:30:25 +0000304 DBG("%s: count=%d, timeout=%d, freq=%lu\n",
Harvey Harrisonfa9363c2008-03-05 18:24:58 -0800305 __func__, count, timeout, freq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306
307 /* if the count is bigger than the watchdog register,
308 then work out what we need to do (and if) we can
309 actually make this value
310 */
311
312 if (count >= 0x10000) {
Doug Anderson17862442013-11-26 16:57:19 -0800313 divisor = DIV_ROUND_UP(count, 0xffff);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314
Doug Anderson17862442013-11-26 16:57:19 -0800315 if (divisor > 0x100) {
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530316 dev_err(wdt->dev, "timeout %d too big\n", timeout);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 return -EINVAL;
318 }
319 }
320
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 DBG("%s: timeout=%d, divisor=%d, count=%d (%08x)\n",
Doug Anderson17862442013-11-26 16:57:19 -0800322 __func__, timeout, divisor, count, DIV_ROUND_UP(count, divisor));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323
Doug Anderson17862442013-11-26 16:57:19 -0800324 count = DIV_ROUND_UP(count, divisor);
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530325 wdt->count = count;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326
327 /* update the pre-scaler */
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530328 wtcon = readl(wdt->reg_base + S3C2410_WTCON);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329 wtcon &= ~S3C2410_WTCON_PRESCALE_MASK;
330 wtcon |= S3C2410_WTCON_PRESCALE(divisor-1);
331
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530332 writel(count, wdt->reg_base + S3C2410_WTDAT);
333 writel(wtcon, wdt->reg_base + S3C2410_WTCON);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334
Hans de Goede5f2430f2012-05-11 12:00:27 +0200335 wdd->timeout = (count * divisor) / freq;
Wim Van Sebroeck0197c1c2012-02-29 20:20:58 +0100336
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337 return 0;
338}
339
Wim Van Sebroecka77dba72009-04-14 20:20:07 +0000340#define OPTIONS (WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341
Alan Cox41dc8b72008-08-04 17:54:46 +0100342static const struct watchdog_info s3c2410_wdt_ident = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 .options = OPTIONS,
344 .firmware_version = 0,
345 .identity = "S3C2410 Watchdog",
346};
347
Wolfram Sang25dc46e2011-09-26 15:40:14 +0200348static struct watchdog_ops s3c2410wdt_ops = {
349 .owner = THIS_MODULE,
350 .start = s3c2410wdt_start,
351 .stop = s3c2410wdt_stop,
352 .ping = s3c2410wdt_keepalive,
353 .set_timeout = s3c2410wdt_set_heartbeat,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354};
355
Wolfram Sang25dc46e2011-09-26 15:40:14 +0200356static struct watchdog_device s3c2410_wdd = {
357 .info = &s3c2410_wdt_ident,
358 .ops = &s3c2410wdt_ops,
Fabio Porceddac1fd5f62013-02-14 09:14:25 +0100359 .timeout = CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360};
361
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362/* interrupt handler code */
363
David Howells7d12e782006-10-05 14:55:46 +0100364static irqreturn_t s3c2410wdt_irq(int irqno, void *param)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365{
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530366 struct s3c2410_wdt *wdt = platform_get_drvdata(param);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530368 dev_info(wdt->dev, "watchdog timer expired (irq)\n");
369
370 s3c2410wdt_keepalive(&wdt->wdt_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 return IRQ_HANDLED;
372}
Ben Dookse02f8382009-10-30 00:30:25 +0000373
Doug Anderson0f1dd982013-11-25 15:36:43 -0800374#ifdef CONFIG_ARM_S3C24XX_CPUFREQ
Ben Dookse02f8382009-10-30 00:30:25 +0000375
376static int s3c2410wdt_cpufreq_transition(struct notifier_block *nb,
377 unsigned long val, void *data)
378{
379 int ret;
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530380 struct s3c2410_wdt *wdt = freq_to_wdt(nb);
Ben Dookse02f8382009-10-30 00:30:25 +0000381
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530382 if (!s3c2410wdt_is_running(wdt))
Ben Dookse02f8382009-10-30 00:30:25 +0000383 goto done;
384
385 if (val == CPUFREQ_PRECHANGE) {
386 /* To ensure that over the change we don't cause the
387 * watchdog to trigger, we perform an keep-alive if
388 * the watchdog is running.
389 */
390
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530391 s3c2410wdt_keepalive(&wdt->wdt_device);
Ben Dookse02f8382009-10-30 00:30:25 +0000392 } else if (val == CPUFREQ_POSTCHANGE) {
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530393 s3c2410wdt_stop(&wdt->wdt_device);
Ben Dookse02f8382009-10-30 00:30:25 +0000394
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530395 ret = s3c2410wdt_set_heartbeat(&wdt->wdt_device,
396 wdt->wdt_device.timeout);
Ben Dookse02f8382009-10-30 00:30:25 +0000397
398 if (ret >= 0)
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530399 s3c2410wdt_start(&wdt->wdt_device);
Ben Dookse02f8382009-10-30 00:30:25 +0000400 else
401 goto err;
402 }
403
404done:
405 return 0;
406
407 err:
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530408 dev_err(wdt->dev, "cannot set new value for timeout %d\n",
409 wdt->wdt_device.timeout);
Ben Dookse02f8382009-10-30 00:30:25 +0000410 return ret;
411}
412
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530413static inline int s3c2410wdt_cpufreq_register(struct s3c2410_wdt *wdt)
Ben Dookse02f8382009-10-30 00:30:25 +0000414{
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530415 wdt->freq_transition.notifier_call = s3c2410wdt_cpufreq_transition;
416
417 return cpufreq_register_notifier(&wdt->freq_transition,
Ben Dookse02f8382009-10-30 00:30:25 +0000418 CPUFREQ_TRANSITION_NOTIFIER);
419}
420
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530421static inline void s3c2410wdt_cpufreq_deregister(struct s3c2410_wdt *wdt)
Ben Dookse02f8382009-10-30 00:30:25 +0000422{
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530423 wdt->freq_transition.notifier_call = s3c2410wdt_cpufreq_transition;
424
425 cpufreq_unregister_notifier(&wdt->freq_transition,
Ben Dookse02f8382009-10-30 00:30:25 +0000426 CPUFREQ_TRANSITION_NOTIFIER);
427}
428
429#else
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530430
431static inline int s3c2410wdt_cpufreq_register(struct s3c2410_wdt *wdt)
Ben Dookse02f8382009-10-30 00:30:25 +0000432{
433 return 0;
434}
435
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530436static inline void s3c2410wdt_cpufreq_deregister(struct s3c2410_wdt *wdt)
Ben Dookse02f8382009-10-30 00:30:25 +0000437{
438}
439#endif
440
Doug Andersoncffc9a62013-12-06 13:08:07 -0800441static inline unsigned int s3c2410wdt_get_bootstatus(struct s3c2410_wdt *wdt)
442{
443 unsigned int rst_stat;
444 int ret;
445
446 if (!(wdt->drv_data->quirks & QUIRK_HAS_RST_STAT))
447 return 0;
448
449 ret = regmap_read(wdt->pmureg, wdt->drv_data->rst_stat_reg, &rst_stat);
450 if (ret)
451 dev_warn(wdt->dev, "Couldn't get RST_STAT register\n");
452 else if (rst_stat & BIT(wdt->drv_data->rst_stat_bit))
453 return WDIOF_CARDRESET;
454
455 return 0;
456}
457
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530458/* s3c2410_get_wdt_driver_data */
459static inline struct s3c2410_wdt_variant *
460get_wdt_drv_data(struct platform_device *pdev)
461{
462 if (pdev->dev.of_node) {
463 const struct of_device_id *match;
464 match = of_match_node(s3c2410_wdt_match, pdev->dev.of_node);
465 return (struct s3c2410_wdt_variant *)match->data;
466 } else {
467 return (struct s3c2410_wdt_variant *)
468 platform_get_device_id(pdev)->driver_data;
469 }
470}
471
Bill Pemberton2d991a12012-11-19 13:21:41 -0500472static int s3c2410wdt_probe(struct platform_device *pdev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473{
Ben Dookse8ef92b2007-06-14 12:08:55 +0100474 struct device *dev;
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530475 struct s3c2410_wdt *wdt;
476 struct resource *wdt_mem;
477 struct resource *wdt_irq;
Ben Dooks46b814d2007-06-14 12:08:54 +0100478 unsigned int wtcon;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479 int started = 0;
480 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481
Harvey Harrisonfa9363c2008-03-05 18:24:58 -0800482 DBG("%s: probe=%p\n", __func__, pdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483
Ben Dookse8ef92b2007-06-14 12:08:55 +0100484 dev = &pdev->dev;
Ben Dookse8ef92b2007-06-14 12:08:55 +0100485
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530486 wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
487 if (!wdt)
488 return -ENOMEM;
489
490 wdt->dev = &pdev->dev;
491 spin_lock_init(&wdt->lock);
492 wdt->wdt_device = s3c2410_wdd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530494 wdt->drv_data = get_wdt_drv_data(pdev);
Doug Andersoncffc9a62013-12-06 13:08:07 -0800495 if (wdt->drv_data->quirks & QUIRKS_HAVE_PMUREG) {
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530496 wdt->pmureg = syscon_regmap_lookup_by_phandle(dev->of_node,
497 "samsung,syscon-phandle");
498 if (IS_ERR(wdt->pmureg)) {
499 dev_err(dev, "syscon regmap lookup failed.\n");
500 return PTR_ERR(wdt->pmureg);
501 }
502 }
503
MyungJoo Ham78d3e002012-01-13 14:14:23 +0900504 wdt_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
505 if (wdt_irq == NULL) {
506 dev_err(dev, "no irq resource specified\n");
507 ret = -ENOENT;
508 goto err;
509 }
510
511 /* get the memory region for the watchdog timer */
Julia Lawallbd5cc112013-08-14 11:11:24 +0200512 wdt_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530513 wdt->reg_base = devm_ioremap_resource(dev, wdt_mem);
514 if (IS_ERR(wdt->reg_base)) {
515 ret = PTR_ERR(wdt->reg_base);
Jingoo Han04ecc7d2013-01-10 11:06:33 +0900516 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517 }
518
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530519 DBG("probe: mapped reg_base=%p\n", wdt->reg_base);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530521 wdt->clock = devm_clk_get(dev, "watchdog");
522 if (IS_ERR(wdt->clock)) {
Ben Dookse8ef92b2007-06-14 12:08:55 +0100523 dev_err(dev, "failed to find watchdog clock source\n");
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530524 ret = PTR_ERR(wdt->clock);
Jingoo Han04ecc7d2013-01-10 11:06:33 +0900525 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 }
527
Sachin Kamat01b6af92014-03-04 15:04:35 +0530528 ret = clk_prepare_enable(wdt->clock);
529 if (ret < 0) {
530 dev_err(dev, "failed to enable clock\n");
531 return ret;
532 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530534 ret = s3c2410wdt_cpufreq_register(wdt);
MyungJoo Ham78d3e002012-01-13 14:14:23 +0900535 if (ret < 0) {
Jingoo Han38289242013-03-14 10:30:21 +0900536 dev_err(dev, "failed to register cpufreq\n");
Ben Dookse02f8382009-10-30 00:30:25 +0000537 goto err_clk;
538 }
539
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530540 watchdog_set_drvdata(&wdt->wdt_device, wdt);
541
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 /* see if we can actually set the requested timer margin, and if
543 * not, try the default value */
544
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530545 watchdog_init_timeout(&wdt->wdt_device, tmr_margin, &pdev->dev);
546 ret = s3c2410wdt_set_heartbeat(&wdt->wdt_device,
547 wdt->wdt_device.timeout);
548 if (ret) {
549 started = s3c2410wdt_set_heartbeat(&wdt->wdt_device,
Alan Cox41dc8b72008-08-04 17:54:46 +0100550 CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551
Alan Cox41dc8b72008-08-04 17:54:46 +0100552 if (started == 0)
553 dev_info(dev,
554 "tmr_margin value out of range, default %d used\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME);
Alan Cox41dc8b72008-08-04 17:54:46 +0100556 else
Wim Van Sebroecka77dba72009-04-14 20:20:07 +0000557 dev_info(dev, "default timer value is out of range, "
558 "cannot start\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559 }
560
Jingoo Han04ecc7d2013-01-10 11:06:33 +0900561 ret = devm_request_irq(dev, wdt_irq->start, s3c2410wdt_irq, 0,
562 pdev->name, pdev);
MyungJoo Ham78d3e002012-01-13 14:14:23 +0900563 if (ret != 0) {
564 dev_err(dev, "failed to install irq (%d)\n", ret);
565 goto err_cpufreq;
566 }
567
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530568 watchdog_set_nowayout(&wdt->wdt_device, nowayout);
Wim Van Sebroeckff0b3cd2011-11-29 16:24:16 +0100569
Doug Andersoncffc9a62013-12-06 13:08:07 -0800570 wdt->wdt_device.bootstatus = s3c2410wdt_get_bootstatus(wdt);
571
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530572 ret = watchdog_register_device(&wdt->wdt_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700573 if (ret) {
Wolfram Sang25dc46e2011-09-26 15:40:14 +0200574 dev_err(dev, "cannot register watchdog (%d)\n", ret);
Jingoo Han04ecc7d2013-01-10 11:06:33 +0900575 goto err_cpufreq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576 }
577
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530578 ret = s3c2410wdt_mask_and_disable_reset(wdt, false);
579 if (ret < 0)
580 goto err_unregister;
581
Linus Torvalds1da177e2005-04-16 15:20:36 -0700582 if (tmr_atboot && started == 0) {
Ben Dookse8ef92b2007-06-14 12:08:55 +0100583 dev_info(dev, "starting watchdog timer\n");
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530584 s3c2410wdt_start(&wdt->wdt_device);
Ben Dooks655516c2006-04-19 23:02:56 +0100585 } else if (!tmr_atboot) {
586 /* if we're not enabling the watchdog, then ensure it is
587 * disabled if it has been left running from the bootloader
588 * or other source */
589
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530590 s3c2410wdt_stop(&wdt->wdt_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591 }
592
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530593 platform_set_drvdata(pdev, wdt);
594
Ben Dooks46b814d2007-06-14 12:08:54 +0100595 /* print out a statement of readiness */
596
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530597 wtcon = readl(wdt->reg_base + S3C2410_WTCON);
Ben Dooks46b814d2007-06-14 12:08:54 +0100598
Ben Dookse8ef92b2007-06-14 12:08:55 +0100599 dev_info(dev, "watchdog %sactive, reset %sabled, irq %sabled\n",
Ben Dooks46b814d2007-06-14 12:08:54 +0100600 (wtcon & S3C2410_WTCON_ENABLE) ? "" : "in",
Dmitry Artamonow20403e82011-11-16 12:46:13 +0400601 (wtcon & S3C2410_WTCON_RSTEN) ? "en" : "dis",
602 (wtcon & S3C2410_WTCON_INTEN) ? "en" : "dis");
Alan Cox41dc8b72008-08-04 17:54:46 +0100603
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604 return 0;
Ben Dooks0b6dd8a2006-12-18 10:31:32 +0000605
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530606 err_unregister:
607 watchdog_unregister_device(&wdt->wdt_device);
608
Ben Dookse02f8382009-10-30 00:30:25 +0000609 err_cpufreq:
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530610 s3c2410wdt_cpufreq_deregister(wdt);
Ben Dookse02f8382009-10-30 00:30:25 +0000611
Ben Dooks0b6dd8a2006-12-18 10:31:32 +0000612 err_clk:
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530613 clk_disable_unprepare(wdt->clock);
Ben Dooks0b6dd8a2006-12-18 10:31:32 +0000614
MyungJoo Ham78d3e002012-01-13 14:14:23 +0900615 err:
Ben Dooks0b6dd8a2006-12-18 10:31:32 +0000616 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617}
618
Bill Pemberton4b12b892012-11-19 13:26:24 -0500619static int s3c2410wdt_remove(struct platform_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700620{
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530621 int ret;
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530622 struct s3c2410_wdt *wdt = platform_get_drvdata(dev);
Wim Van Sebroeck9a372562010-05-21 08:11:42 +0000623
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530624 ret = s3c2410wdt_mask_and_disable_reset(wdt, true);
625 if (ret < 0)
626 return ret;
627
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530628 watchdog_unregister_device(&wdt->wdt_device);
Ben Dookse02f8382009-10-30 00:30:25 +0000629
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530630 s3c2410wdt_cpufreq_deregister(wdt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530632 clk_disable_unprepare(wdt->clock);
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530633
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634 return 0;
635}
636
Russell King3ae5eae2005-11-09 22:32:44 +0000637static void s3c2410wdt_shutdown(struct platform_device *dev)
Ben Dooks94f1e9f2005-08-17 09:04:52 +0200638{
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530639 struct s3c2410_wdt *wdt = platform_get_drvdata(dev);
640
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530641 s3c2410wdt_mask_and_disable_reset(wdt, true);
642
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530643 s3c2410wdt_stop(&wdt->wdt_device);
Ben Dooks94f1e9f2005-08-17 09:04:52 +0200644}
645
Jingoo Han0183984c2013-03-14 10:31:21 +0900646#ifdef CONFIG_PM_SLEEP
Ben Dooksaf4bb822005-08-17 09:03:23 +0200647
Jingoo Han0183984c2013-03-14 10:31:21 +0900648static int s3c2410wdt_suspend(struct device *dev)
Ben Dooksaf4bb822005-08-17 09:03:23 +0200649{
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530650 int ret;
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530651 struct s3c2410_wdt *wdt = dev_get_drvdata(dev);
652
Russell King9480e302005-10-28 09:52:56 -0700653 /* Save watchdog state, and turn it off. */
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530654 wdt->wtcon_save = readl(wdt->reg_base + S3C2410_WTCON);
655 wdt->wtdat_save = readl(wdt->reg_base + S3C2410_WTDAT);
Ben Dooksaf4bb822005-08-17 09:03:23 +0200656
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530657 ret = s3c2410wdt_mask_and_disable_reset(wdt, true);
658 if (ret < 0)
659 return ret;
660
Russell King9480e302005-10-28 09:52:56 -0700661 /* Note that WTCNT doesn't need to be saved. */
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530662 s3c2410wdt_stop(&wdt->wdt_device);
Ben Dooksaf4bb822005-08-17 09:03:23 +0200663
664 return 0;
665}
666
Jingoo Han0183984c2013-03-14 10:31:21 +0900667static int s3c2410wdt_resume(struct device *dev)
Ben Dooksaf4bb822005-08-17 09:03:23 +0200668{
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530669 int ret;
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530670 struct s3c2410_wdt *wdt = dev_get_drvdata(dev);
Ben Dooksaf4bb822005-08-17 09:03:23 +0200671
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530672 /* Restore watchdog state. */
673 writel(wdt->wtdat_save, wdt->reg_base + S3C2410_WTDAT);
674 writel(wdt->wtdat_save, wdt->reg_base + S3C2410_WTCNT);/* Reset count */
675 writel(wdt->wtcon_save, wdt->reg_base + S3C2410_WTCON);
Ben Dooksaf4bb822005-08-17 09:03:23 +0200676
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530677 ret = s3c2410wdt_mask_and_disable_reset(wdt, false);
678 if (ret < 0)
679 return ret;
680
Jingoo Han0183984c2013-03-14 10:31:21 +0900681 dev_info(dev, "watchdog %sabled\n",
Leela Krishna Amudalaaf4ea632013-08-27 15:36:03 +0530682 (wdt->wtcon_save & S3C2410_WTCON_ENABLE) ? "en" : "dis");
Ben Dooksaf4bb822005-08-17 09:03:23 +0200683
684 return 0;
685}
Jingoo Han0183984c2013-03-14 10:31:21 +0900686#endif
Ben Dooksaf4bb822005-08-17 09:03:23 +0200687
Jingoo Han0183984c2013-03-14 10:31:21 +0900688static SIMPLE_DEV_PM_OPS(s3c2410wdt_pm_ops, s3c2410wdt_suspend,
689 s3c2410wdt_resume);
Ben Dooksaf4bb822005-08-17 09:03:23 +0200690
Russell King3ae5eae2005-11-09 22:32:44 +0000691static struct platform_driver s3c2410wdt_driver = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700692 .probe = s3c2410wdt_probe,
Bill Pemberton82268712012-11-19 13:21:12 -0500693 .remove = s3c2410wdt_remove,
Ben Dooks94f1e9f2005-08-17 09:04:52 +0200694 .shutdown = s3c2410wdt_shutdown,
Leela Krishna Amudala4f1f6532013-12-06 11:17:47 +0530695 .id_table = s3c2410_wdt_ids,
Russell King3ae5eae2005-11-09 22:32:44 +0000696 .driver = {
697 .owner = THIS_MODULE,
698 .name = "s3c2410-wdt",
Jingoo Han0183984c2013-03-14 10:31:21 +0900699 .pm = &s3c2410wdt_pm_ops,
Wim Van Sebroeck3016a552012-05-03 05:24:17 +0000700 .of_match_table = of_match_ptr(s3c2410_wdt_match),
Russell King3ae5eae2005-11-09 22:32:44 +0000701 },
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702};
703
Sachin Kamat6b761b22012-07-12 17:17:40 +0530704module_platform_driver(s3c2410wdt_driver);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705
Ben Dooksaf4bb822005-08-17 09:03:23 +0200706MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>, "
707 "Dimitry Andric <dimitry.andric@tomtom.com>");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708MODULE_DESCRIPTION("S3C2410 Watchdog Device Driver");
709MODULE_LICENSE("GPL");