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#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdint.h>
#include <sys/mman.h>
#include <unistd.h>
#define CM_PER_REG_START 0x44e00000
#define CM_PER_REG_LENGTH 1024
#define CM_PER_EPWMSS0_CLKCTRL_OFFSET 0xd4
#define CM_PER_EPWMSS1_CLKCTRL_OFFSET 0xcc
#define CM_PER_EPWMSS2_CLKCTRL_OFFSET 0xd8
#define PWM_CLOCK_ENABLE 0x2
#define PWM_CLOCK_DISABLE 0x0
#define PWM_LIST_MAX 3
int PWM_OFFSETS[PWM_LIST_MAX] = {
CM_PER_EPWMSS0_CLKCTRL_OFFSET / sizeof (uint32_t),
CM_PER_EPWMSS1_CLKCTRL_OFFSET / sizeof (uint32_t),
CM_PER_EPWMSS2_CLKCTRL_OFFSET / sizeof (uint32_t)
};
void print_usage (const char *message)
{
if (message)
printf ("%s\n", message);
printf ("pwm_clock <-e | -d> <PWM [PWM]>\n\n");
}
int main (int argc, char **argv)
{
int i;
int *cur_list = NULL;
int *cur_list_index = NULL;
int enable_list[PWM_LIST_MAX];
int enable_list_index = 0;
int disable_list[PWM_LIST_MAX];
int disable_list_index = 0;
int dev_mem_fd;
volatile uint32_t *cm_per_regs;
for (i = 0; i < PWM_LIST_MAX; ++i) {
enable_list[i] = -1;
disable_list[i] = -1;
}
for (i = 1; i < argc; ++i) {
if (strncmp (argv[i], "-e", 2) == 0) {
cur_list = enable_list;
cur_list_index = &enable_list_index;
}
else if (strncmp (argv[i], "-d", 2) == 0) {
cur_list = disable_list;
cur_list_index = &disable_list_index;
}
else {
if (!cur_list) {
print_usage (0);
return 1;
}
if (*cur_list_index >= PWM_LIST_MAX) {
print_usage ("Too many PWM's specified for an option");
return 1;
}
cur_list[*cur_list_index] = atoi (argv[i]);
++*cur_list_index;
}
}
dev_mem_fd = open ("/dev/mem", O_RDWR);
if (dev_mem_fd == -1) {
perror ("open failed");
return 1;
}
cm_per_regs = (volatile uint32_t *)mmap (NULL, CM_PER_REG_LENGTH,
PROT_READ | PROT_WRITE, MAP_SHARED, dev_mem_fd, CM_PER_REG_START);
if (cm_per_regs == (volatile uint32_t *)MAP_FAILED) {
perror ("mmap failed");
close (dev_mem_fd);
return 1;
}
for (i = 0; i < PWM_LIST_MAX && enable_list[i] != -1; ++i) {
if (enable_list[i] < 0 || enable_list[i] >= PWM_LIST_MAX) {
printf ("Invalid PWM specified, %d\n", enable_list[i]);
goto out;
}
printf ("Enabling PWM %d\n", enable_list[i]);
cm_per_regs[PWM_OFFSETS[enable_list[i]]] = PWM_CLOCK_ENABLE;
}
for (i = 0; i < PWM_LIST_MAX && disable_list[i] != -1; ++i) {
if (disable_list[i] < 0 || disable_list[i] >= PWM_LIST_MAX) {
printf ("Invalid PWM specified, %d\n", disable_list[i]);
goto out;
}
printf ("Disabling PWM %d\n", disable_list[i]);
cm_per_regs[PWM_OFFSETS[disable_list[i]]] = PWM_CLOCK_DISABLE;
}
out:
munmap ((void *)cm_per_regs, CM_PER_REG_LENGTH);
close (dev_mem_fd);
return 0;
}