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