On Monday 21 March 2016 16:13:34 Gabriele Mazzotta wrote: > 2016-03-21 13:17 GMT+01:00 Pali Rohár <pali.rohar@xxxxxxxxx>: > > On Friday 18 March 2016 23:44:23 Gabriele Mazzotta wrote: > >> +#ifdef CONFIG_PM_SLEEP > >> +static void ACPI_SYSTEM_XFACE rbtn_acpi_clear_flag(void *context) > >> +{ > >> + struct rbtn_data *rbtn_data = context; > >> + > >> + rbtn_data->suspended = false; > >> +} > >> + > >> +static int rbtn_suspend(struct device *dev) > >> +{ > >> + struct acpi_device *device = to_acpi_device(dev); > >> + struct rbtn_data *rbtn_data = acpi_driver_data(device); > >> + > >> + rbtn_data->suspended = true; > >> + > >> + return 0; > >> +} > >> + > >> +static int rbtn_resume(struct device *dev) > >> +{ > >> + struct acpi_device *device = to_acpi_device(dev); > >> + struct rbtn_data *rbtn_data = acpi_driver_data(device); > >> + acpi_status status; > >> + > >> + /* > >> + * Clear the flag only after we received the extra > >> + * ACPI notification. > >> + */ > >> + status = acpi_os_execute(OSL_NOTIFY_HANDLER, > >> + rbtn_acpi_clear_flag, rbtn_data); > >> + if (ACPI_FAILURE(status)) > >> + rbtn_data->suspended = false; > > > > I case when acpi_os_execute success it calls rbtn_acpi_clear_flag, > > right? And that will set suspended to false. When acpi_os_execute fails, > > then it set suspended too to false... Then whole acpi_os_execute doing > > just "barrier" after which suspended flag can be set to false. So I > > think rbtn_acpi_clear_flag function is not needed here. > > > > Cannot you pass NULL or empty function pointer as callback? Or what was > > reason to do that flag clearing at "two places"? > > acpi_os_execute doesn't wait for the callback to be executed, so > I can't clear the flag from rbtn_resume. acpi_os_execute calls callback asynchronously later? Or what exactly do it? -- Pali Rohár pali.rohar@xxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe platform-driver-x86" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html