Power Management

[shalanyang]

Hello, I want to know how to use SPI,USB,and Ethernet power management in imx8qxp mek board? could you help me ? for example： how could I suspend or resume in imx8qxp(SPI&&USB&&Ethernet Module)? thanks!!!!

[joanxie]

for power management, you can refer to the application note as below:

https://www.nxp.com/docs/en/application-note/AN12338.pdf 

[shalanyang]

tks,Joan,

              for example, I want to wakeup SOC by SPI,In spi_fsl_lpspi.c the function is empty(imx8qxp mek board)

              the driver code is follow:

#ifdef CONFIG_PM_SLEEP
static int fsl_lpspi_suspend(struct device *dev)
{
int ret;

pinctrl_pm_select_sleep_state(dev);
ret = pm_runtime_force_suspend(dev);
return ret;
}

static int fsl_lpspi_resume(struct device *dev)
{
int ret;

ret = pm_runtime_force_resume(dev);
if (ret) {
dev_err(dev, "Error in resume: %d\n", ret);
return ret;
}

pinctrl_pm_select_default_state(dev);

return 0;
}
#endif /* CONFIG_PM_SLEEP */

static inline int pm_generic_runtime_suspend(struct device *dev) { return 0; }
static inline int pm_generic_runtime_resume(struct device *dev) { return 0; }
static inline int pm_runtime_force_suspend(struct device *dev) { return 0; }
static inline int pm_runtime_force_resume(struct device *dev) { return 0; }

the SPI can not support suspend or resume?

[shalanyang]

Could you help me ???