mirror of
https://github.com/torvalds/linux.git
synced 2024-12-01 08:31:37 +00:00
9e66fb5244
This patch adds an example showing how to use PFSM devices from a userspace application. The PMIC is armed to be triggered by a RTC alarm to execute state transition. Signed-off-by: Julien Panis <jpanis@baylibre.com> Message-ID: <20230511095126.105104-7-jpanis@baylibre.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
126 lines
2.9 KiB
C
126 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* TPS6594 PFSM userspace example
|
|
*
|
|
* Copyright (C) 2023 BayLibre Incorporated - https://www.baylibre.com/
|
|
*
|
|
* This example shows how to use PFSMs from a userspace application,
|
|
* on TI j721s2 platform. The PMIC is armed to be triggered by a RTC
|
|
* alarm to execute state transition (RETENTION to ACTIVE).
|
|
*/
|
|
|
|
#include <fcntl.h>
|
|
#include <stdio.h>
|
|
#include <sys/ioctl.h>
|
|
#include <unistd.h>
|
|
|
|
#include <linux/rtc.h>
|
|
#include <linux/tps6594_pfsm.h>
|
|
|
|
#define ALARM_DELTA_SEC 30
|
|
|
|
#define RTC_A "/dev/rtc0"
|
|
|
|
#define PMIC_NB 3
|
|
#define PMIC_A "/dev/pfsm-0-0x48"
|
|
#define PMIC_B "/dev/pfsm-0-0x4c"
|
|
#define PMIC_C "/dev/pfsm-2-0x58"
|
|
|
|
static const char * const dev_pfsm[] = {PMIC_A, PMIC_B, PMIC_C};
|
|
|
|
int main(int argc, char *argv[])
|
|
{
|
|
int i, ret, fd_rtc, fd_pfsm[PMIC_NB] = { 0 };
|
|
struct rtc_time rtc_tm;
|
|
struct pmic_state_opt pmic_opt = { 0 };
|
|
unsigned long data;
|
|
|
|
fd_rtc = open(RTC_A, O_RDONLY);
|
|
if (fd_rtc < 0) {
|
|
perror("Failed to open RTC device.");
|
|
goto out;
|
|
}
|
|
|
|
for (i = 0 ; i < PMIC_NB ; i++) {
|
|
fd_pfsm[i] = open(dev_pfsm[i], O_RDWR);
|
|
if (fd_pfsm[i] < 0) {
|
|
perror("Failed to open PFSM device.");
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/* Read RTC date/time */
|
|
ret = ioctl(fd_rtc, RTC_RD_TIME, &rtc_tm);
|
|
if (ret < 0) {
|
|
perror("Failed to read RTC date/time.");
|
|
goto out;
|
|
}
|
|
printf("Current RTC date/time is %d-%d-%d, %02d:%02d:%02d.\n",
|
|
rtc_tm.tm_mday, rtc_tm.tm_mon + 1, rtc_tm.tm_year + 1900,
|
|
rtc_tm.tm_hour, rtc_tm.tm_min, rtc_tm.tm_sec);
|
|
|
|
/* Set RTC alarm to ALARM_DELTA_SEC sec in the future, and check for rollover */
|
|
rtc_tm.tm_sec += ALARM_DELTA_SEC;
|
|
if (rtc_tm.tm_sec >= 60) {
|
|
rtc_tm.tm_sec %= 60;
|
|
rtc_tm.tm_min++;
|
|
}
|
|
if (rtc_tm.tm_min == 60) {
|
|
rtc_tm.tm_min = 0;
|
|
rtc_tm.tm_hour++;
|
|
}
|
|
if (rtc_tm.tm_hour == 24)
|
|
rtc_tm.tm_hour = 0;
|
|
ret = ioctl(fd_rtc, RTC_ALM_SET, &rtc_tm);
|
|
if (ret < 0) {
|
|
perror("Failed to set RTC alarm.");
|
|
goto out;
|
|
}
|
|
|
|
/* Enable alarm interrupts */
|
|
ret = ioctl(fd_rtc, RTC_AIE_ON, 0);
|
|
if (ret < 0) {
|
|
perror("Failed to enable alarm interrupts.");
|
|
goto out;
|
|
}
|
|
printf("Waiting %d seconds for alarm...\n", ALARM_DELTA_SEC);
|
|
|
|
/*
|
|
* Set RETENTION state with options for PMIC_C/B/A respectively.
|
|
* Since PMIC_A is master, it should be the last one to be configured.
|
|
*/
|
|
pmic_opt.ddr_retention = 1;
|
|
for (i = PMIC_NB - 1 ; i >= 0 ; i--) {
|
|
printf("Set RETENTION state for PMIC_%d.\n", i);
|
|
sleep(1);
|
|
ret = ioctl(fd_pfsm[i], PMIC_SET_RETENTION_STATE, &pmic_opt);
|
|
if (ret < 0) {
|
|
perror("Failed to set RETENTION state.");
|
|
goto out_reset;
|
|
}
|
|
}
|
|
|
|
/* This blocks until the alarm ring causes an interrupt */
|
|
ret = read(fd_rtc, &data, sizeof(unsigned long));
|
|
if (ret < 0)
|
|
perror("Failed to get RTC alarm.");
|
|
else
|
|
puts("Alarm rang.\n");
|
|
|
|
out_reset:
|
|
ioctl(fd_rtc, RTC_AIE_OFF, 0);
|
|
|
|
/* Set ACTIVE state for PMIC_A */
|
|
ioctl(fd_pfsm[0], PMIC_SET_ACTIVE_STATE, 0);
|
|
|
|
out:
|
|
for (i = 0 ; i < PMIC_NB ; i++)
|
|
if (fd_pfsm[i])
|
|
close(fd_pfsm[i]);
|
|
|
|
if (fd_rtc)
|
|
close(fd_rtc);
|
|
|
|
return 0;
|
|
}
|