int board_pwm_setup(void)
{
static bool initialized = false;
struct pwm_lowerhalf_s *pwm;
int ret;
/* Have we already initialized? */
if (!initialized)
{
/* Call stm32_pwminitialize() to get an instance of the PWM interface */
pwm = stm32_pwminitialize(NUCLEO_F303RE_PWMTIMER);
if (pwm == NULL)
{
pwmerr("ERROR: Failed to get the STM32 PWM lower half\n");
return -ENODEV;
}
/* Register the PWM driver at "/dev/pwm0" */
ret = pwm_register("/dev/pwm0", pwm);
if (ret < 0)
{
pwmerr("ERROR: pwm_register failed: %d\n", ret);
return ret;
}
/* Now we are initialized */
initialized = true;
}
return OK;
}
int pwm_register(FAR const char *path, FAR struct pwm_lowerhalf_s *dev)
{
FAR struct pwm_upperhalf_s *upper;
/* Allocate the upper-half data structure */
upper = (FAR struct pwm_upperhalf_s *)kmm_zalloc(sizeof(struct pwm_upperhalf_s));
if (!upper)
{
pwmerr("Allocation failed\n");
return -ENOMEM;
}
/* Initialize the PWM device structure (it was already zeroed by kmm_zalloc()) */
sem_init(&upper->exclsem, 0, 1);
#ifdef CONFIG_PWM_PULSECOUNT
sem_init(&upper->waitsem, 0, 0);
#endif
upper->dev = dev;
/* Register the PWM device */
pwminfo("Registering %s\n", path);
return register_driver(path, &g_pwmops, 0666, upper);
}
int pwm_register(FAR const char *path, FAR struct pwm_lowerhalf_s *dev)
{
FAR struct pwm_upperhalf_s *upper;
/* Allocate the upper-half data structure */
upper = (FAR struct pwm_upperhalf_s *)kmm_zalloc(sizeof(struct pwm_upperhalf_s));
if (!upper)
{
pwmerr("Allocation failed\n");
return -ENOMEM;
}
/* Initialize the PWM device structure (it was already zeroed by kmm_zalloc()) */
sem_init(&upper->exclsem, 0, 1);
#ifdef CONFIG_PWM_PULSECOUNT
sem_init(&upper->waitsem, 0, 0);
/* The wait semaphore is used for signaling and, hence, should not have priority
* inheritance enabled.
*/
sem_setprotocol(&upper->waitsem, SEM_PRIO_NONE);
#endif
upper->dev = dev;
/* Register the PWM device */
pwminfo("Registering %s\n", path);
return register_driver(path, &g_pwmops, 0666, upper);
}
