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authorLinus Torvalds <torvalds@linux-foundation.org>2015-04-22 09:18:17 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-04-22 09:18:17 -0700
commit7d2b6ef19cf0f98cef17aa5185de3631a618710a (patch)
treed4e87f3c47837fef59ef15273f89f68b73d963af /drivers/watchdog
parent5c73cc4b6c83e88863a5de869cc5df3b913aef4a (diff)
parent7415d97ee2b809119270fc3a365968ff8d4f544b (diff)
Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC driver updates from Olof Johansson: "Driver updates for v4.1. Some of these are for drivers/soc, where we find more and more SoC-specific drivers these days. Some are for other driver subsystems where we have received acks from the appropriate maintainers. The larger parts of this branch are: - MediaTek support for their PMIC wrapper interface, a high-level interface for talking to the system PMIC over a dedicated I2C interface. - Qualcomm SCM driver has been moved to drivers/firmware. It's used for CPU up/down and needs to be in a shared location for arm/arm64 common code. - cleanup of ARM-CCI PMU code. - another set of cleanusp to the OMAP GPMC code" * tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (43 commits) soc/mediatek: Remove unused variables clocksource: atmel-st: select MFD_SYSCON soc: mediatek: Add PMIC wrapper for MT8135 and MT8173 SoCs arm-cci: Fix CCI PMU event validation arm-cci: Split the code for PMU vs driver support arm-cci: Get rid of secure transactions for PMU driver arm-cci: Abstract the CCI400 PMU specific definitions arm-cci: Rearrange code for splitting PMU vs driver code drivers: cci: reject groups spanning multiple HW PMUs ARM: at91: remove useless include clocksource: atmel-st: remove mach/hardware dependency clocksource: atmel-st: use syscon/regmap ARM: at91: time: move the system timer driver to drivers/clocksource ARM: at91: properly initialize timer ARM: at91: at91rm9200: remove deprecated arm_pm_restart watchdog: at91rm9200: implement restart handler watchdog: at91rm9200: use the system timer syscon mfd: syscon: Add atmel system timer registers definition ARM: at91/dt: declare atmel,at91rm9200-st as a syscon soc: qcom: gsbi: Add support for ADM CRCI muxing ...
Diffstat (limited to 'drivers/watchdog')
-rw-r--r--drivers/watchdog/Kconfig2
-rw-r--r--drivers/watchdog/at91rm9200_wdt.c61
2 files changed, 55 insertions, 8 deletions
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 16f202350997..ce4f3a7f95fd 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -154,7 +154,7 @@ config ARM_SP805_WATCHDOG
config AT91RM9200_WATCHDOG
tristate "AT91RM9200 watchdog"
- depends on SOC_AT91RM9200
+ depends on SOC_AT91RM9200 && MFD_SYSCON
help
Watchdog timer embedded into AT91RM9200 chips. This will reboot your
system when the timeout is reached.
diff --git a/drivers/watchdog/at91rm9200_wdt.c b/drivers/watchdog/at91rm9200_wdt.c
index d244112d5b6f..41cecb55766c 100644
--- a/drivers/watchdog/at91rm9200_wdt.c
+++ b/drivers/watchdog/at91rm9200_wdt.c
@@ -12,27 +12,32 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/bitops.h>
+#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/atmel-st.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/platform_device.h>
+#include <linux/reboot.h>
+#include <linux/regmap.h>
#include <linux/types.h>
#include <linux/watchdog.h>
#include <linux/uaccess.h>
#include <linux/of.h>
#include <linux/of_device.h>
-#include <mach/at91_st.h>
#define WDT_DEFAULT_TIME 5 /* seconds */
#define WDT_MAX_TIME 256 /* seconds */
static int wdt_time = WDT_DEFAULT_TIME;
static bool nowayout = WATCHDOG_NOWAYOUT;
+static struct regmap *regmap_st;
module_param(wdt_time, int, 0);
MODULE_PARM_DESC(wdt_time, "Watchdog time in seconds. (default="
@@ -50,12 +55,33 @@ static unsigned long at91wdt_busy;
/* ......................................................................... */
+static int at91rm9200_restart(struct notifier_block *this,
+ unsigned long mode, void *cmd)
+{
+ /*
+ * Perform a hardware reset with the use of the Watchdog timer.
+ */
+ regmap_write(regmap_st, AT91_ST_WDMR,
+ AT91_ST_RSTEN | AT91_ST_EXTEN | 1);
+ regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST);
+
+ mdelay(2000);
+
+ pr_emerg("Unable to restart system\n");
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block at91rm9200_restart_nb = {
+ .notifier_call = at91rm9200_restart,
+ .priority = 192,
+};
+
/*
* Disable the watchdog.
*/
static inline void at91_wdt_stop(void)
{
- at91_st_write(AT91_ST_WDMR, AT91_ST_EXTEN);
+ regmap_write(regmap_st, AT91_ST_WDMR, AT91_ST_EXTEN);
}
/*
@@ -63,9 +89,9 @@ static inline void at91_wdt_stop(void)
*/
static inline void at91_wdt_start(void)
{
- at91_st_write(AT91_ST_WDMR, AT91_ST_EXTEN | AT91_ST_RSTEN |
+ regmap_write(regmap_st, AT91_ST_WDMR, AT91_ST_EXTEN | AT91_ST_RSTEN |
(((65536 * wdt_time) >> 8) & AT91_ST_WDV));
- at91_st_write(AT91_ST_CR, AT91_ST_WDRST);
+ regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST);
}
/*
@@ -73,7 +99,7 @@ static inline void at91_wdt_start(void)
*/
static inline void at91_wdt_reload(void)
{
- at91_st_write(AT91_ST_CR, AT91_ST_WDRST);
+ regmap_write(regmap_st, AT91_ST_CR, AT91_ST_WDRST);
}
/* ......................................................................... */
@@ -203,16 +229,32 @@ static struct miscdevice at91wdt_miscdev = {
static int at91wdt_probe(struct platform_device *pdev)
{
+ struct device *dev = &pdev->dev;
+ struct device *parent;
int res;
if (at91wdt_miscdev.parent)
return -EBUSY;
at91wdt_miscdev.parent = &pdev->dev;
+ parent = dev->parent;
+ if (!parent) {
+ dev_err(dev, "no parent\n");
+ return -ENODEV;
+ }
+
+ regmap_st = syscon_node_to_regmap(parent->of_node);
+ if (!regmap_st)
+ return -ENODEV;
+
res = misc_register(&at91wdt_miscdev);
if (res)
return res;
+ res = register_restart_handler(&at91rm9200_restart_nb);
+ if (res)
+ dev_warn(dev, "failed to register restart handler\n");
+
pr_info("AT91 Watchdog Timer enabled (%d seconds%s)\n",
wdt_time, nowayout ? ", nowayout" : "");
return 0;
@@ -220,8 +262,13 @@ static int at91wdt_probe(struct platform_device *pdev)
static int at91wdt_remove(struct platform_device *pdev)
{
+ struct device *dev = &pdev->dev;
int res;
+ res = unregister_restart_handler(&at91rm9200_restart_nb);
+ if (res)
+ dev_warn(dev, "failed to unregister restart handler\n");
+
res = misc_deregister(&at91wdt_miscdev);
if (!res)
at91wdt_miscdev.parent = NULL;
@@ -267,7 +314,7 @@ static struct platform_driver at91wdt_driver = {
.suspend = at91wdt_suspend,
.resume = at91wdt_resume,
.driver = {
- .name = "at91_wdt",
+ .name = "atmel_st_watchdog",
.of_match_table = at91_wdt_dt_ids,
},
};
@@ -296,4 +343,4 @@ module_exit(at91_wdt_exit);
MODULE_AUTHOR("Andrew Victor");
MODULE_DESCRIPTION("Watchdog driver for Atmel AT91RM9200");
MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:at91_wdt");
+MODULE_ALIAS("platform:atmel_st_watchdog");