Commit 75932094 authored by Lee Jones's avatar Lee Jones
Browse files

mfd: ab8500-sysctrl: Add new reset function 



Add a new reset function which uses the AB WD with 0 timeout.

Signed-off-by: default avatarLee Jones <lee.jones@linaro.org>
Acked-by: default avatarSamuel Ortiz <sameo@linux.intel.com>
parent 9581ae39

drivers/mfd/ab8500-sysctrl.c

+63 −0
Original line number Diff line number Diff line
@@ -15,6 +15,12 @@ 
#include <linux/mfd/abx500/ab8500.h>

#include <linux/mfd/abx500/ab8500-sysctrl.h>



/* RtcCtrl bits */

#define AB8500_ALARM_MIN_LOW  0x08

#define AB8500_ALARM_MIN_MID 0x09

#define RTC_CTRL 0x0B

#define RTC_ALARM_ENABLE 0x4



static struct device *sysctrl_dev;



void ab8500_power_off(void)
@@ -79,6 +85,63 @@ void ab8500_power_off(void) 
	}

}



/*

 * Use the AB WD to reset the platform. It will perform a hard

 * reset instead of a soft reset. Write the reset reason to

 * the AB before reset, which can be read upon restart.

 */

void ab8500_restart(char mode, const char *cmd)

{

	struct ab8500_platform_data *plat;

	struct ab8500_sysctrl_platform_data *pdata;

	u16 reason = 0;

	u8 val;



	if (sysctrl_dev == NULL) {

		pr_err("%s: sysctrl not initialized\n", __func__);

		return;

	}



	plat = dev_get_platdata(sysctrl_dev->parent);

	pdata = plat->sysctrl;

	if (pdata->reboot_reason_code)

		reason = pdata->reboot_reason_code(cmd);

	else

		pr_warn("[%s] No reboot reason set. Default reason %d\n",

			__func__, reason);



	/*

	 * Disable RTC alarm, just a precaution so that no alarm

	 * is running when WD reset is executed.

	 */

	abx500_get_register_interruptible(sysctrl_dev, AB8500_RTC,

		RTC_CTRL , &val);

	abx500_set_register_interruptible(sysctrl_dev, AB8500_RTC,

		RTC_CTRL , (val & ~RTC_ALARM_ENABLE));



	/*

	 * Android is not using the RTC alarm registers during reboot

	 * so we borrow them for writing the reason of reset

	 */



	/* reason[8 LSB] */

	val = reason & 0xFF;

	abx500_set_register_interruptible(sysctrl_dev, AB8500_RTC,

		AB8500_ALARM_MIN_LOW , val);



	/* reason[8 MSB] */

	val = (reason>>8) & 0xFF;

	abx500_set_register_interruptible(sysctrl_dev, AB8500_RTC,

		AB8500_ALARM_MIN_MID , val);



	/* Setting WD timeout to 0 */

	ab8500_sysctrl_write(AB8500_MAINWDOGTIMER, 0xFF, 0x0);



	/* Setting the parameters to AB8500 WD*/

	ab8500_sysctrl_write(AB8500_MAINWDOGCTRL, 0xFF, (AB8500_ENABLE_WD |

		AB8500_WD_RESTART_ON_EXPIRE | AB8500_KICK_WD));

}



static inline bool valid_bank(u8 bank)

{

	return ((bank == AB8500_SYS_CTRL1_BLOCK) ||

include/linux/mfd/abx500/ab8500-sysctrl.h

+6 −0
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 


int ab8500_sysctrl_read(u16 reg, u8 *value);

int ab8500_sysctrl_write(u16 reg, u8 mask, u8 value);

void ab8500_restart(char mode, const char *cmd);



#else
@@ -40,6 +41,7 @@ static inline int ab8500_sysctrl_clear(u16 reg, u8 bits) 
/* Configuration data for SysClkReq1RfClkBuf - SysClkReq8RfClkBuf */

struct ab8500_sysctrl_platform_data {

	u8 initial_req_buf_config[8];

	u16 (*reboot_reason_code)(const char *cmd);

};



/* Registers */
@@ -299,4 +301,8 @@ struct ab8500_sysctrl_platform_data { 
#define AB9540_SYSCLK12BUF4VALID_SYSCLK12BUF4VALID_MASK 0xFF

#define AB9540_SYSCLK12BUF4VALID_SYSCLK12BUF4VALID_SHIFT 0



#define AB8500_ENABLE_WD 0x1

#define AB8500_KICK_WD 0x2

#define AB8500_WD_RESTART_ON_EXPIRE 0x10



#endif /* __AB8500_SYSCTRL_H */